Three crucial hurdles hinder studies on human cytomegalovirus(HCMV): strict species specificity, differences between in vivo and in vitro infection, and the complexity of gene regulation. Ever since the sequencing of ...Three crucial hurdles hinder studies on human cytomegalovirus(HCMV): strict species specificity, differences between in vivo and in vitro infection, and the complexity of gene regulation. Ever since the sequencing of the whole genome was first accomplished, functional studies on individual genes have been the mainstream in the CMV field. Gene regulation has therefore been elucidated in a more detailed fashion. However, viral gene regulation is largely controlled by both cellular and viral components. In other words, viral gene expression is determined by the virus–host interaction. Generally, cells respond to viral infection in a defensive pattern; at the same time, viruses try to counteract the cellular defense or else hide in the host(latency). Viruses evolve effective strategies against cellular defense in order to achieve replicative success. Whether or not they are successful, cellular defenses remain in the whole viral replication cycle: entry, immediate–early(IE) gene expression, early gene expression, DNA replication, late gene expression, and viral egress. Many viral strategies against cellular defense, and which occur in the immediate–early time of viral infection, have been documented. In this review, we will summarize the documented biological functions of IE1 and pp71 proteins, especially with regard to how they counteract cellular intrinsic defenses.展开更多
Objective To investigate the relationship between CMV infection and renal allograft rejection. Methods 39 kidney biopsies and transplant nephrectomies were collected and investigated for CMV immediate early antigen ...Objective To investigate the relationship between CMV infection and renal allograft rejection. Methods 39 kidney biopsies and transplant nephrectomies were collected and investigated for CMV immediate early antigen by immunohistochemistry. Results In 14 out of 39 tissue specimens CMV immediate early antigen were found. 8 biopsies from normal donor kidneys were negative; only 1 (10%) in 10 tissue specimens with early stage acute rejection was positive; 5(55.6%) in 9 biopsies with late stage acute rejection and 8 (66.7%) in 12 tissue blocks with chronic rejection were positive. Compared with normal kidney tissues, the infections in tissues with early stage acute rejection didn't increase obviously, but increased obviously in kidney tissue specimens with late stage rejection and with chronic rejection (P< 0.05). Conclusion CMV infection appears to contribute to late stage acute rejection and chronic rejection after renal transplantation.展开更多
Objective To analyze the upstream region of radiation-induced junB gene. Methods Four plasmids containing 250 bp, 590 bp, 900 bp and 1650 bp, and CAT reporter gene were constructed separately and introduced to L8704 c...Objective To analyze the upstream region of radiation-induced junB gene. Methods Four plasmids containing 250 bp, 590 bp, 900 bp and 1650 bp, and CAT reporter gene were constructed separately and introduced to L8704 cells. The cells were irradiated with 2 Gy X-rays and incubated at different intervals. Total RNA was extracted from the cells and fluctuation of the CAT mRNA level was assessed by the RNA ratio of CAT/β-actin measured by quantitative Northern blot hybridization. Results CAT mRNA expression containing 900 bp and 1560 bpjunB promoter remarkably and rapidly increased, and reached its peak 30min after 2 Gy X-my irradiation. Conclusions 590-900 bp fragments located in the upstream region of junB gene play an important role in the early process of cells against radiation.展开更多
Objective Despite dramatic advances in surgical technique and perioperative care,some children still suffered serious adverse event in early postoperative period which were associated with increased morbidity and mort...Objective Despite dramatic advances in surgical technique and perioperative care,some children still suffered serious adverse event in early postoperative period which were associated with increased morbidity and mortality.There was little information regarding the impact of adverse events on the postoperative recovery,especially the serious adverse events occurring immediately after surgery.We sought to evaluate the early postoperative serious adverse events and examine the impact of them on postoperative recovery.展开更多
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec...BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function.展开更多
Early life stress correlates with a higher prevalence of neurological disorders,including autism,attention-deficit/hyperactivity disorder,schizophrenia,depression,and Parkinson's disease.These conditions,primarily...Early life stress correlates with a higher prevalence of neurological disorders,including autism,attention-deficit/hyperactivity disorder,schizophrenia,depression,and Parkinson's disease.These conditions,primarily involving abnormal development and damage of the dopaminergic system,pose significant public health challenges.Microglia,as the primary immune cells in the brain,are crucial in regulating neuronal circuit development and survival.From the embryonic stage to adulthood,microglia exhibit stage-specific gene expression profiles,transcriptome characteristics,and functional phenotypes,enhancing the susceptibility to early life stress.However,the role of microglia in mediating dopaminergic system disorders under early life stress conditions remains poorly understood.This review presents an up-to-date overview of preclinical studies elucidating the impact of early life stress on microglia,leading to dopaminergic system disorders,along with the underlying mechanisms and therapeutic potential for neurodegenerative and neurodevelopmental conditions.Impaired microglial activity damages dopaminergic neurons by diminishing neurotrophic support(e.g.,insulin-like growth factor-1)and hinders dopaminergic axon growth through defective phagocytosis and synaptic pruning.Furthermore,blunted microglial immunoreactivity suppresses striatal dopaminergic circuit development and reduces neuronal transmission.Furthermore,inflammation and oxidative stress induced by activated microglia can directly damage dopaminergic neurons,inhibiting dopamine synthesis,reuptake,and receptor activity.Enhanced microglial phagocytosis inhibits dopamine axon extension.These long-lasting effects of microglial perturbations may be driven by early life stress–induced epigenetic reprogramming of microglia.Indirectly,early life stress may influence microglial function through various pathways,such as astrocytic activation,the hypothalamic–pituitary–adrenal axis,the gut–brain axis,and maternal immune signaling.Finally,various therapeutic strategies and molecular mechanisms for targeting microglia to restore the dopaminergic system were summarized and discussed.These strategies include classical antidepressants and antipsychotics,antibiotics and anti-inflammatory agents,and herbal-derived medicine.Further investigations combining pharmacological interventions and genetic strategies are essential to elucidate the causal role of microglial phenotypic and functional perturbations in the dopaminergic system disrupted by early life stress.展开更多
Objective This study was to evaluate the efficacy and safety of a short acting reduced dose fibrinolytic regimen to promote early infarct related artery (IRA) patency for acyute myocardial infarction (AMI) patients re...Objective This study was to evaluate the efficacy and safety of a short acting reduced dose fibrinolytic regimen to promote early infarct related artery (IRA) patency for acyute myocardial infarction (AMI) patients referred for percutaneous coronary intervention (PCI).Methods Following aspirin and heparin, 166 patients were randomized to a 50 mg bolus of recombinant tissue type plasminogen activator(rt PA) or to a same volume sodium chloride injection followed by immediate primary PCI. The end points included patency rates on catheterization laboratory (cath lab) arrival, revascularization results when PCI was performed, complication rates, left ventricular function and restored patency rate following PCI. Results Patency on cath lab arrival was 64% with rt PA (34% TIMI 3,30% TIMI 2), while 31% of placebo (13% TIMI 3, 18% TIMI 2). There was no difference in the restored TIMI 3 rates of IRA between the two groups (85% vs 87%). No difference were observed in stroke or major bleeding. Left ventricular function was similar in both groups (52±9% vs 50±8%), but left ventricular ejection fraction fraction (LVEF) was higher with patent IRA (TIMI 3) on cath lab arrival than that of others (56±12% vs 48±10%).Conclusions Strategy thrombolytic regimens were compatible with subsequent PCI lead to more frequenc early recanalization (before cath lab arrival), which facilitates greater left ventricular function preservation with no augmentation of adverse events.展开更多
The pharmacokinetics of morphine sulphate was studied in 10 Chinese healthy volunteers after a single oral dose. Blood samples were collected before and after administration of controlled release tablets (CRMS, 30 mg)...The pharmacokinetics of morphine sulphate was studied in 10 Chinese healthy volunteers after a single oral dose. Blood samples were collected before and after administration of controlled release tablets (CRMS, 30 mg) and immediate release tablets (IRMS, 20 mg). The plasma concentration of morphine was determined by GC MS. The pharmacokinetic parameters of controlled release tablets and immediate release tablets were calculated∶ C max was 19.38±3.80 and 21.27±6.21 ng/ml, t max was 2.36 ±0.37 h and 0.56±0.16 h, t 1/2β was 3.53±0.87 and 3.03±0.74 h, AUC was 145.15±17.65 and 93.08±16.65 ng/ml, respectively. The steady state plasma concentration of morphine sulphate in cancer patients after multiple doses was achieved, C max of CRMS and IRMS was 27.43±0.33 ng/ml and 22.68±0.16 ng/ml, C min of CRMS and IRMS was 19.45±1.44 ng/ml and 18.14±0.49 ng/ml, respectively.展开更多
Although neurophysiological and psychophysical proof of osseoperception is accumulating, histomorphometric evidence for the neural mechanisms of functional compensation following immediate and delayed implant loading ...Although neurophysiological and psychophysical proof of osseoperception is accumulating, histomorphometric evidence for the neural mechanisms of functional compensation following immediate and delayed implant loading is still lacking. For this randomized split-mouth study, six mongrel dogs randomly received one of four treatment protocols at 36 implant-recipient sites over 16 weeks (third maxillary incisor, third and fourth mandibular premolar): immediate implant placement and immediate loading (liP+ IL); delayed implant placement and delayed loading (DIP+DL); delayed implant placement and immediate loading (DIP+IL); and natural extraction socket healing (control). Histomorphometry was performed in the peri-implant bone and soft tissues within 300 pm around the implants. Immunocytochemistry and transmission electron microscopy were used to confirm the presence of neural structures and to reveal their ultrastructural characteristics, respectively. Myelinated nerve fibres densely populated the peri-implant crestal gingival and apical regions, although they were also identified in the woven bone and in the osteons near the implant threads. Compared with the control group in the mandible, the group that received IIP+IL showed a higher innervation (in N.mm^-2, 5.94±1.12 vs. 3.15±0.63, P〈0.001) and smaller fibre diameter (in pm, 1.37±0.05 vs. 1.64±0.13, P=0.016), smaller axon diameter (in pm, 0.89±0.05 vs. 1.24±0,10, P=0.009) and g-ratio (0.64±0.04 vs. 0.76±0.05, P〈0.001) in the middle region around the implants. Compared with DIP+IL in the mandible, IIP+IL had a higher nerve density (in N.mm^-2, 13.23±2.54 vs. 9.64±1.86, P=0.027), greater fibre diameter (in pm, 1.32±0.02 vs. 1.20±0.04, P=0.021), greater axon diameter (in μm, 0.92±0.01 vs. 0.89±0.03, P=-0.035) and lower g-ratio (0.69±0.01 vs. 0.74±0.01, P=-0.033) in the apical region around the implants. It may be assumed that the treatment protocol with liP+ IL is the preferred method to allow optimized peri-implant re-innervation, but further functional measurements are still required.展开更多
AIM: To investigate the clinicopathological risk factors for immediate post-operative fatal recurrence of hepatocellular carcinoma (HCC), which may have practical implication and contribute to establishing high ris...AIM: To investigate the clinicopathological risk factors for immediate post-operative fatal recurrence of hepatocellular carcinoma (HCC), which may have practical implication and contribute to establishing high risk patients for pre- or post-operative preventive measures against HCC recurrence. METHODS: From June 1994 to May 2004, 269 patients who received curative resection for HCC were reviewed. Of these patients, those who demonstrated diffuse intrahepatic or multiple systemic recurrent lesions within 6 mo after surgery were investigated (fatal recurrence group). The remaining patients were designated as the control group, and the two groups were compared for clinicopathologic risk factors. RESULTS: Among the 269 patients reviewed, 30 patients were enrolled in the fatal recurrence group. Among the latter, 20 patients showed diffuse intrahepatic recurrence type and 10 showed multiple systemic recurrence type. Multivariate analysis between the fatal recurrence group and control group showed that preoperative serum alpha-fetoprotein (AFP) level was greater than 1 000 μg/L (P= 0.02; odds ratio = 2.98), tumor size greater than 6.5 cm (P= 0.03; OR= 2.98), and presence of microvascular invasion (P= 0.01; OR=4.89) were the risk factors in the fatal recurrence group. The 48.1% of the patients who had all the three risk factors and the 220 of those who had two risk factors experienced fatal recurrence within 6 mo after surgery. CONCLUSION: Three distinct risk factors for immediate post-operative fatal recurrence of HCC after curative resection are pre-operative serum AFP level 〉 1 000 μg/L,tumor size〉6.5 cm, and microvascular invasion. The high risk patients with two or more risk factors should be the candidates for various adjuvant clinical trials.展开更多
BACKGROUND There are some challenges concerning immediate implant placement in the molar region.Platelet-rich fibrin(PRF),an autologous biomaterial,has been used widely for periodontal intra-bony defects,sinus augment...BACKGROUND There are some challenges concerning immediate implant placement in the molar region.Platelet-rich fibrin(PRF),an autologous biomaterial,has been used widely for periodontal intra-bony defects,sinus augmentation,socket preservation,and gingival recession.However,the literature remains scarce for reports on immediate implants with PRF,particularly in the case of fresh molar extraction socket.CASE SUMMARY The patient was a 43-year-old woman with maxillary molar vertical crown-root fracture.She underwent flapless immediate implant placement into the fresh molar socket with PRF.At the follow-up visit 15 d post procedure,the vascularization of soft tissue was visible.There was no swelling or pain after the surgery.Six months postoperatively,the regeneration of bone and soft tissues was visible.Subsequently,the definitive restoration was placed.The patient was satisfied with the aesthetic outcomes.CONCLUSION The flapless immediate implant placement into the fresh molar socket with PRF is a feasible procedure.This case report demonstrates that PRF promotes bone and soft tissue regeneration apart from having an enhanced anti-inflammatory ability.Furthermore,the procedure involves a minimally invasive technique,thus reducing the surgical complexity.展开更多
Objective:The number of immediate breast reconstruction(IBR)procedures has been increasing in China.This study aimed to investigate the oncological safety of IBR,and to compare the survival and surgical outcomes betwe...Objective:The number of immediate breast reconstruction(IBR)procedures has been increasing in China.This study aimed to investigate the oncological safety of IBR,and to compare the survival and surgical outcomes between implant-based and autologous reconstruction.Methods:Data from patients diagnosed with invasive breast cancer who underwent immediate total breast reconstruction between 2001 and 2016 were retrospectively reviewed.Long-term breast cancer-specific survival(BCSS),disease-free survival(DFS),and locoregional recurrence-free survival(LRFS)were evaluated.Patient satisfaction with the breast was compared between the implantbased and autologous groups.BCSS,DFS,and LRFS were compared between groups after propensity score matching(PSM).Results:A total of 784 IBR procedures were identified,of which 584 were performed on patients with invasive breast cancer(implantbased,n=288;autologous,n=296).With a median follow-up of 71.3 months,the 10-year estimates of BCSS,DFS,and LRFS were 88.9%[95%confidence interval(CI)(85.1%–93.0%)],79.6%[95%CI(74.7%–84.8%)],and 94.0%[95%CI(90.3%–97.8%)],respectively.A total of 124 patients completed the Breast-Q questionnaire,and no statistically significant differences were noted between groups(P=0.823).After PSM with 27 variables,no statistically significant differences in BCSS,DFS,and LRFS were found between the implant-based(n=177)and autologous(n=177)groups.Further stratification according to staging,histological grade,lymph node status,and lymph-venous invasion status revealed no significant survival differences between groups.Conclusions:Both immediate implant-based and autologous reconstruction were reasonable choices with similar long-term oncological outcomes and patient-reported satisfaction among patients with invasive breast cancer in China.展开更多
Implant insertion is an alternative to classical treatment with bridges after tooth extraction or traumatic tooth loss in the anterior and premolar region of the upper and lower jaw. Nevertheless both types of prosthe...Implant insertion is an alternative to classical treatment with bridges after tooth extraction or traumatic tooth loss in the anterior and premolar region of the upper and lower jaw. Nevertheless both types of prosthetic treatment inhere major gingival aesthetic pitfalls by physiological vertical and horizontal resorption. Aim of the study was to investigate if the immediate insertion of root analogue single-stage implants and prosthetic treatment could prevent gingival recessions and bone resorption thus keeping the natural gingival aesthetics untouched. Between 2003 and 2006, 348 root analogue Q1-Implants (TRINON Karlsruhe GmbH/Germany) were inserted in 342 patients’s premolar and molar regions immediately after tooth extraction or traumatic tooth loss and treated with provisional resin crowns. The observation period with recurring 6-month clinical and radiographic check-ups was a minimum of 5 years. Of 348 inserted implants 4 (1.15%) were lost resulting in an overall success rate of 98.85%. In the first 12 weeks after surgery a mean recession of the buccal gingival margin of 0.2 mm (SD 0.34) could be detected, after final prosthetic treatment an overall mean recession of 0.2 mm (SD 0.13) within the survey period. Immediate implant insertion of root analogue single stage implants and immediate prosthetic treatment with provisional resin crowns after minimal invasive tooth extraction seems to be appropriate to prevent bone resorptions of the buccal alveolar crest and the recessions of the gingiva and papillae and thus suggests to be the preferable treatment to keep the natural gingival and papillary aesthetics untouched preventing further traumatic surgical gingival reconstructions.展开更多
To reduce the cost of backfilling coal mining and utilize the underground space of coal mines,a new backfilling mining method with low backfilling rate called constructional backfilling coal mining(CBCM)is proposed.Th...To reduce the cost of backfilling coal mining and utilize the underground space of coal mines,a new backfilling mining method with low backfilling rate called constructional backfilling coal mining(CBCM)is proposed.The "backfilling body-immediate roof" cooperative bearing structure of CBCM is analyzed by establishing the model of the medium thick plate on an elastic foundation.The influence of the backfilling rate on the stability of overlying strata is analyzed by the numerical simulation experiment.The control effect of CBCM is verified by a physic similar simulation test.The economic benefit of CBCM is analyzed.The conclusions are:the deformation characteristics of the immediate roof and critical backfilling spacing in CBCM can be analyzed based on the Hu Haichang’s theory.Exerting the bearing capacity of the immediate roof is beneficial to the stability of the overlying strata.The CBCM has a good control effect on the overburden in Xinyang Mine when the backfilling rate is lower than 25%.The backfilling cost of per ton coal is 37.39 yuan/t when the backfilling rate is 13.7%,with a decrease rate of 56.63%than the full-filling.The research results can provide theoretical support for the application of CBCM in coal mining.展开更多
AIM:To investigate the efficacy of short-term peginterferon(PEG-IFN)monotherapy for chronic hepatitis C patients who achieved an immediate virological response.METHODS:Defining an"immediate virological response(I...AIM:To investigate the efficacy of short-term peginterferon(PEG-IFN)monotherapy for chronic hepatitis C patients who achieved an immediate virological response.METHODS:Defining an"immediate virological response(IVR)"as the loss of serum hepatitis C virus(HCV) RNA 7 d after the first administration of PEG-IFNα,we conducted a 12-wk course of PEG-IFNα2a monotherapy without the addition of ribavirin for 38 patients who had low pretreatment HCV RNA load and exhibited IVR.The patients included 21 men and 17 women,whose ages ranged from 22 to 77 years(mean±SD:52.0±17.8 years).There were 4 patients with HCV genotype 1b,23 patients with genotype 2a and 4 patients with genotype 2b.HCV genotype was not determined for the remaining 7 patients.Patients were categorized into a sustained virological response(SVR)group,if serum HCV RNA remained negative for 24 wk after the end of treatment,or into a relapse group.RESULTS:Based on the intention-to-treat analysis,35 patients(92.1%)achieved SVR.One patient(2.6%)relapsed with serum HCV RNA 12 wk after the end of treatment.Two patients(5.3%)withdrew from the study during the 24-wk follow-up period.With regard to the HCV RNA genotype,the SVR rates were 100%(4/4) for genotype 1b,95.7%(22/23)for genotype 2a and 100%(4/4)for genotype 2b.The SVR rate in 7 patients,whose HCV RNA genotypes were not determined,was 71.4%(5/7).CONCLUSION:Short-term PEG-IFNα2a monotherapy is highly effective for chronic hepatitis C patients who have low pretreatment HCV RNA load and exhibit IVR.展开更多
BACKGROUND In this case,platelet-rich fibrin(PRF)was added to guided tissue regeneration as a biomaterial in proper order for immediate planting in aesthetic area with periapical infection.CASE SUMMARY With the histor...BACKGROUND In this case,platelet-rich fibrin(PRF)was added to guided tissue regeneration as a biomaterial in proper order for immediate planting in aesthetic area with periapical infection.CASE SUMMARY With the history of endodontic failure in maxillary central incisor,a 34-year-old female patient required the extraction of maxillary anterior residual root and immediate implantation.Cone beam computed tomography and clinical observation were used to assess the regeneration of soft and bone tissue.Before operation,cone beam computed tomography showed the anterior residual root had serious periapical periodontitis with insufficient labial bone in the aesthetic zone.The patient underwent immediate implant placement and reconstruction of the bone substitution by modified guided bone regeneration.The barrier was a three-layer structure of PRF-collagen membrane-PRF that covered the mixture of PRF and Bio-Oss to promote both osteogenesis and soft tissue healing.At 6 mo postoperatively,the definitive crown was placed after accomplished finial impression.One-year follow-up showed a satisfactory aesthetic effect with no obvious absorption of the labial bone and soft tissue.CONCLUSION The use of PRF in combination with guided bone regeneration can serve as a reliable and simple adjuvant for immediate implanting in infected socket and result in a stable osteogenic effect with good aesthetic outcome.展开更多
We introduced the hydrophilic groups to acrylic bone cement to improve compliance and achieve more interdigitation between the bone and the acrylic bone cement in order to create better substrates for immediate loadin...We introduced the hydrophilic groups to acrylic bone cement to improve compliance and achieve more interdigitation between the bone and the acrylic bone cement in order to create better substrates for immediate loading. FTIR-ATR, contact angle, and maximum breach torque were employed for measurement. The results reveal that the introduction of hydrophilic functional groups has increased PMMA's surface hydrophilicity after contact angle test. FTIR-ATR results suggest the hydrophilic groups participate in the polymerization reactions, and maximum breach torque of the hydrophilic acrylic bone cements is near 110 Ncm torque. Those effects make it possible for conventional acrylic bone cement application in immediate loading of dental implant.展开更多
We sought to evaluate immediate and delayed micro-tensile bond strength of Panavia F2.0 and Multilink Sprint resin cement to superficial, deep and cervical dentin. Thirty-six freshly extracted non-carious human molars...We sought to evaluate immediate and delayed micro-tensile bond strength of Panavia F2.0 and Multilink Sprint resin cement to superficial, deep and cervical dentin. Thirty-six freshly extracted non-carious human molars were sectioned in the mesiodistal direction to expose three different dentin regions including superficial dentin (1 mm below the dentine-enamel junction), deep dentin (1 mm above the highest pulp horn) and cervical dentin (0.5 mm above the cemento-enamel junction and 0.5 mm below the dentine-enamel junction). Resin cements were applied on dentin surfaces and composite blocks were luted under constant seating pressure. Each group was divided into three subgroups according to time intervals. Specimens were sectioned to obtain sticks of 1 mm2 in diameter and subjected to microtensile bond strength testing at a cross head speed of 1 mrn/min. Both resin cements showed higher micro-tensile bond strength to superficial dentin than that to deep or cervical dentin (P 〈 0.001). Micro-ten- sile bond strengths of Panavia F2.0 were higher than those of Multilink Sprint at different dentin regions (P 〈 0.001). Immediate "micro-tensile bond strengths were higher than those of delayed micro-tensile bond strengths for both resin cements (P 〈 0.001). It was concluded that resin cements with different chemical formulations and applications yield significantly different micro-tensile bond strengths to different dentin regions.展开更多
In this paper, an EPQ-based inventory policy for an item is presented with stock-dependent demand during two trade credit periods. In addition, there is a provision for 1) an immediate part payment to the wholesaler, ...In this paper, an EPQ-based inventory policy for an item is presented with stock-dependent demand during two trade credit periods. In addition, there is a provision for 1) an immediate part payment to the wholesaler, 2) borrowing some money from money lending source for the immediate part payment, 3) here supplier or wholesaler offers a trade credit period to his retailer and retailer also offers a trade credit period to his customer. Against the above conjectures inventory model has been formulated with respect to the retailer’s point of view for minimizing the total inventory cost. The non-linear optimization method-Generalized Reduced Gradient (GRG) method is used to find the optimal solutions. Lastly Numerical examples are set to illustrate this model. Finally we use LINGO software to solve this model.展开更多
基金supported by a pilot grant from the Research Center for Minority Institutes (RCMI) program (2G12RR003050-24/8G12MD007579-27) (Q.T.)an American Cancer Society grant (RSG-090289-01MPC) (Q.T)+1 种基金NIH/NIAID SC1AI112785 (Q.T.)the Ponce Health Sciences University/RCMI Publications Office (G12 RR003050/8G12MD007579-27)
文摘Three crucial hurdles hinder studies on human cytomegalovirus(HCMV): strict species specificity, differences between in vivo and in vitro infection, and the complexity of gene regulation. Ever since the sequencing of the whole genome was first accomplished, functional studies on individual genes have been the mainstream in the CMV field. Gene regulation has therefore been elucidated in a more detailed fashion. However, viral gene regulation is largely controlled by both cellular and viral components. In other words, viral gene expression is determined by the virus–host interaction. Generally, cells respond to viral infection in a defensive pattern; at the same time, viruses try to counteract the cellular defense or else hide in the host(latency). Viruses evolve effective strategies against cellular defense in order to achieve replicative success. Whether or not they are successful, cellular defenses remain in the whole viral replication cycle: entry, immediate–early(IE) gene expression, early gene expression, DNA replication, late gene expression, and viral egress. Many viral strategies against cellular defense, and which occur in the immediate–early time of viral infection, have been documented. In this review, we will summarize the documented biological functions of IE1 and pp71 proteins, especially with regard to how they counteract cellular intrinsic defenses.
文摘Objective To investigate the relationship between CMV infection and renal allograft rejection. Methods 39 kidney biopsies and transplant nephrectomies were collected and investigated for CMV immediate early antigen by immunohistochemistry. Results In 14 out of 39 tissue specimens CMV immediate early antigen were found. 8 biopsies from normal donor kidneys were negative; only 1 (10%) in 10 tissue specimens with early stage acute rejection was positive; 5(55.6%) in 9 biopsies with late stage acute rejection and 8 (66.7%) in 12 tissue blocks with chronic rejection were positive. Compared with normal kidney tissues, the infections in tissues with early stage acute rejection didn't increase obviously, but increased obviously in kidney tissue specimens with late stage rejection and with chronic rejection (P< 0.05). Conclusion CMV infection appears to contribute to late stage acute rejection and chronic rejection after renal transplantation.
基金This project was supported by Japanese Research Development Corporation (JRDC).
文摘Objective To analyze the upstream region of radiation-induced junB gene. Methods Four plasmids containing 250 bp, 590 bp, 900 bp and 1650 bp, and CAT reporter gene were constructed separately and introduced to L8704 cells. The cells were irradiated with 2 Gy X-rays and incubated at different intervals. Total RNA was extracted from the cells and fluctuation of the CAT mRNA level was assessed by the RNA ratio of CAT/β-actin measured by quantitative Northern blot hybridization. Results CAT mRNA expression containing 900 bp and 1560 bpjunB promoter remarkably and rapidly increased, and reached its peak 30min after 2 Gy X-my irradiation. Conclusions 590-900 bp fragments located in the upstream region of junB gene play an important role in the early process of cells against radiation.
文摘Objective Despite dramatic advances in surgical technique and perioperative care,some children still suffered serious adverse event in early postoperative period which were associated with increased morbidity and mortality.There was little information regarding the impact of adverse events on the postoperative recovery,especially the serious adverse events occurring immediately after surgery.We sought to evaluate the early postoperative serious adverse events and examine the impact of them on postoperative recovery.
文摘BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function.
基金supported by the National Natural Science Foundation of China,Nos.82304990(to NY),81973748(to JC),82174278(to JC)the National Key R&D Program of China,No.2023YFE0209500(to JC)+4 种基金China Postdoctoral Science Foundation,No.2023M732380(to NY)Guangzhou Key Laboratory of Formula-Pattern of Traditional Chinese Medicine,No.202102010014(to JC)Huang Zhendong Research Fund for Traditional Chinese Medicine of Jinan University,No.201911(to JC)National Innovation and Entrepreneurship Training Program for Undergraduates in China,No.202310559128(to NY and QM)Innovation and Entrepreneurship Training Program for Undergraduates at Jinan University,Nos.CX24380,CX24381(both to NY and QM)。
文摘Early life stress correlates with a higher prevalence of neurological disorders,including autism,attention-deficit/hyperactivity disorder,schizophrenia,depression,and Parkinson's disease.These conditions,primarily involving abnormal development and damage of the dopaminergic system,pose significant public health challenges.Microglia,as the primary immune cells in the brain,are crucial in regulating neuronal circuit development and survival.From the embryonic stage to adulthood,microglia exhibit stage-specific gene expression profiles,transcriptome characteristics,and functional phenotypes,enhancing the susceptibility to early life stress.However,the role of microglia in mediating dopaminergic system disorders under early life stress conditions remains poorly understood.This review presents an up-to-date overview of preclinical studies elucidating the impact of early life stress on microglia,leading to dopaminergic system disorders,along with the underlying mechanisms and therapeutic potential for neurodegenerative and neurodevelopmental conditions.Impaired microglial activity damages dopaminergic neurons by diminishing neurotrophic support(e.g.,insulin-like growth factor-1)and hinders dopaminergic axon growth through defective phagocytosis and synaptic pruning.Furthermore,blunted microglial immunoreactivity suppresses striatal dopaminergic circuit development and reduces neuronal transmission.Furthermore,inflammation and oxidative stress induced by activated microglia can directly damage dopaminergic neurons,inhibiting dopamine synthesis,reuptake,and receptor activity.Enhanced microglial phagocytosis inhibits dopamine axon extension.These long-lasting effects of microglial perturbations may be driven by early life stress–induced epigenetic reprogramming of microglia.Indirectly,early life stress may influence microglial function through various pathways,such as astrocytic activation,the hypothalamic–pituitary–adrenal axis,the gut–brain axis,and maternal immune signaling.Finally,various therapeutic strategies and molecular mechanisms for targeting microglia to restore the dopaminergic system were summarized and discussed.These strategies include classical antidepressants and antipsychotics,antibiotics and anti-inflammatory agents,and herbal-derived medicine.Further investigations combining pharmacological interventions and genetic strategies are essential to elucidate the causal role of microglial phenotypic and functional perturbations in the dopaminergic system disrupted by early life stress.
文摘Objective This study was to evaluate the efficacy and safety of a short acting reduced dose fibrinolytic regimen to promote early infarct related artery (IRA) patency for acyute myocardial infarction (AMI) patients referred for percutaneous coronary intervention (PCI).Methods Following aspirin and heparin, 166 patients were randomized to a 50 mg bolus of recombinant tissue type plasminogen activator(rt PA) or to a same volume sodium chloride injection followed by immediate primary PCI. The end points included patency rates on catheterization laboratory (cath lab) arrival, revascularization results when PCI was performed, complication rates, left ventricular function and restored patency rate following PCI. Results Patency on cath lab arrival was 64% with rt PA (34% TIMI 3,30% TIMI 2), while 31% of placebo (13% TIMI 3, 18% TIMI 2). There was no difference in the restored TIMI 3 rates of IRA between the two groups (85% vs 87%). No difference were observed in stroke or major bleeding. Left ventricular function was similar in both groups (52±9% vs 50±8%), but left ventricular ejection fraction fraction (LVEF) was higher with patent IRA (TIMI 3) on cath lab arrival than that of others (56±12% vs 48±10%).Conclusions Strategy thrombolytic regimens were compatible with subsequent PCI lead to more frequenc early recanalization (before cath lab arrival), which facilitates greater left ventricular function preservation with no augmentation of adverse events.
文摘The pharmacokinetics of morphine sulphate was studied in 10 Chinese healthy volunteers after a single oral dose. Blood samples were collected before and after administration of controlled release tablets (CRMS, 30 mg) and immediate release tablets (IRMS, 20 mg). The plasma concentration of morphine was determined by GC MS. The pharmacokinetic parameters of controlled release tablets and immediate release tablets were calculated∶ C max was 19.38±3.80 and 21.27±6.21 ng/ml, t max was 2.36 ±0.37 h and 0.56±0.16 h, t 1/2β was 3.53±0.87 and 3.03±0.74 h, AUC was 145.15±17.65 and 93.08±16.65 ng/ml, respectively. The steady state plasma concentration of morphine sulphate in cancer patients after multiple doses was achieved, C max of CRMS and IRMS was 27.43±0.33 ng/ml and 22.68±0.16 ng/ml, C min of CRMS and IRMS was 19.45±1.44 ng/ml and 18.14±0.49 ng/ml, respectively.
基金supported by the Natural Science Foundation of China (81000459)the Chinese Scholarship Council
文摘Although neurophysiological and psychophysical proof of osseoperception is accumulating, histomorphometric evidence for the neural mechanisms of functional compensation following immediate and delayed implant loading is still lacking. For this randomized split-mouth study, six mongrel dogs randomly received one of four treatment protocols at 36 implant-recipient sites over 16 weeks (third maxillary incisor, third and fourth mandibular premolar): immediate implant placement and immediate loading (liP+ IL); delayed implant placement and delayed loading (DIP+DL); delayed implant placement and immediate loading (DIP+IL); and natural extraction socket healing (control). Histomorphometry was performed in the peri-implant bone and soft tissues within 300 pm around the implants. Immunocytochemistry and transmission electron microscopy were used to confirm the presence of neural structures and to reveal their ultrastructural characteristics, respectively. Myelinated nerve fibres densely populated the peri-implant crestal gingival and apical regions, although they were also identified in the woven bone and in the osteons near the implant threads. Compared with the control group in the mandible, the group that received IIP+IL showed a higher innervation (in N.mm^-2, 5.94±1.12 vs. 3.15±0.63, P〈0.001) and smaller fibre diameter (in pm, 1.37±0.05 vs. 1.64±0.13, P=0.016), smaller axon diameter (in pm, 0.89±0.05 vs. 1.24±0,10, P=0.009) and g-ratio (0.64±0.04 vs. 0.76±0.05, P〈0.001) in the middle region around the implants. Compared with DIP+IL in the mandible, IIP+IL had a higher nerve density (in N.mm^-2, 13.23±2.54 vs. 9.64±1.86, P=0.027), greater fibre diameter (in pm, 1.32±0.02 vs. 1.20±0.04, P=0.021), greater axon diameter (in μm, 0.92±0.01 vs. 0.89±0.03, P=-0.035) and lower g-ratio (0.69±0.01 vs. 0.74±0.01, P=-0.033) in the apical region around the implants. It may be assumed that the treatment protocol with liP+ IL is the preferred method to allow optimized peri-implant re-innervation, but further functional measurements are still required.
文摘AIM: To investigate the clinicopathological risk factors for immediate post-operative fatal recurrence of hepatocellular carcinoma (HCC), which may have practical implication and contribute to establishing high risk patients for pre- or post-operative preventive measures against HCC recurrence. METHODS: From June 1994 to May 2004, 269 patients who received curative resection for HCC were reviewed. Of these patients, those who demonstrated diffuse intrahepatic or multiple systemic recurrent lesions within 6 mo after surgery were investigated (fatal recurrence group). The remaining patients were designated as the control group, and the two groups were compared for clinicopathologic risk factors. RESULTS: Among the 269 patients reviewed, 30 patients were enrolled in the fatal recurrence group. Among the latter, 20 patients showed diffuse intrahepatic recurrence type and 10 showed multiple systemic recurrence type. Multivariate analysis between the fatal recurrence group and control group showed that preoperative serum alpha-fetoprotein (AFP) level was greater than 1 000 μg/L (P= 0.02; odds ratio = 2.98), tumor size greater than 6.5 cm (P= 0.03; OR= 2.98), and presence of microvascular invasion (P= 0.01; OR=4.89) were the risk factors in the fatal recurrence group. The 48.1% of the patients who had all the three risk factors and the 220 of those who had two risk factors experienced fatal recurrence within 6 mo after surgery. CONCLUSION: Three distinct risk factors for immediate post-operative fatal recurrence of HCC after curative resection are pre-operative serum AFP level 〉 1 000 μg/L,tumor size〉6.5 cm, and microvascular invasion. The high risk patients with two or more risk factors should be the candidates for various adjuvant clinical trials.
基金Supported by Interdisciplinary Project for Ph.D. students of Jilin University,No.10183201846 X.S
文摘BACKGROUND There are some challenges concerning immediate implant placement in the molar region.Platelet-rich fibrin(PRF),an autologous biomaterial,has been used widely for periodontal intra-bony defects,sinus augmentation,socket preservation,and gingival recession.However,the literature remains scarce for reports on immediate implants with PRF,particularly in the case of fresh molar extraction socket.CASE SUMMARY The patient was a 43-year-old woman with maxillary molar vertical crown-root fracture.She underwent flapless immediate implant placement into the fresh molar socket with PRF.At the follow-up visit 15 d post procedure,the vascularization of soft tissue was visible.There was no swelling or pain after the surgery.Six months postoperatively,the regeneration of bone and soft tissues was visible.Subsequently,the definitive restoration was placed.The patient was satisfied with the aesthetic outcomes.CONCLUSION The flapless immediate implant placement into the fresh molar socket with PRF is a feasible procedure.This case report demonstrates that PRF promotes bone and soft tissue regeneration apart from having an enhanced anti-inflammatory ability.Furthermore,the procedure involves a minimally invasive technique,thus reducing the surgical complexity.
基金supported by the Tianjin“Belt and Road”Technological Innovation and Cooperation Grant(Grant No.18PTZWHZ00050)the Special Foundation for Project and Team Development Grant(Grant No.XB202008).
文摘Objective:The number of immediate breast reconstruction(IBR)procedures has been increasing in China.This study aimed to investigate the oncological safety of IBR,and to compare the survival and surgical outcomes between implant-based and autologous reconstruction.Methods:Data from patients diagnosed with invasive breast cancer who underwent immediate total breast reconstruction between 2001 and 2016 were retrospectively reviewed.Long-term breast cancer-specific survival(BCSS),disease-free survival(DFS),and locoregional recurrence-free survival(LRFS)were evaluated.Patient satisfaction with the breast was compared between the implantbased and autologous groups.BCSS,DFS,and LRFS were compared between groups after propensity score matching(PSM).Results:A total of 784 IBR procedures were identified,of which 584 were performed on patients with invasive breast cancer(implantbased,n=288;autologous,n=296).With a median follow-up of 71.3 months,the 10-year estimates of BCSS,DFS,and LRFS were 88.9%[95%confidence interval(CI)(85.1%–93.0%)],79.6%[95%CI(74.7%–84.8%)],and 94.0%[95%CI(90.3%–97.8%)],respectively.A total of 124 patients completed the Breast-Q questionnaire,and no statistically significant differences were noted between groups(P=0.823).After PSM with 27 variables,no statistically significant differences in BCSS,DFS,and LRFS were found between the implant-based(n=177)and autologous(n=177)groups.Further stratification according to staging,histological grade,lymph node status,and lymph-venous invasion status revealed no significant survival differences between groups.Conclusions:Both immediate implant-based and autologous reconstruction were reasonable choices with similar long-term oncological outcomes and patient-reported satisfaction among patients with invasive breast cancer in China.
文摘Implant insertion is an alternative to classical treatment with bridges after tooth extraction or traumatic tooth loss in the anterior and premolar region of the upper and lower jaw. Nevertheless both types of prosthetic treatment inhere major gingival aesthetic pitfalls by physiological vertical and horizontal resorption. Aim of the study was to investigate if the immediate insertion of root analogue single-stage implants and prosthetic treatment could prevent gingival recessions and bone resorption thus keeping the natural gingival aesthetics untouched. Between 2003 and 2006, 348 root analogue Q1-Implants (TRINON Karlsruhe GmbH/Germany) were inserted in 342 patients’s premolar and molar regions immediately after tooth extraction or traumatic tooth loss and treated with provisional resin crowns. The observation period with recurring 6-month clinical and radiographic check-ups was a minimum of 5 years. Of 348 inserted implants 4 (1.15%) were lost resulting in an overall success rate of 98.85%. In the first 12 weeks after surgery a mean recession of the buccal gingival margin of 0.2 mm (SD 0.34) could be detected, after final prosthetic treatment an overall mean recession of 0.2 mm (SD 0.13) within the survey period. Immediate implant insertion of root analogue single stage implants and immediate prosthetic treatment with provisional resin crowns after minimal invasive tooth extraction seems to be appropriate to prevent bone resorptions of the buccal alveolar crest and the recessions of the gingiva and papillae and thus suggests to be the preferable treatment to keep the natural gingival and papillary aesthetics untouched preventing further traumatic surgical gingival reconstructions.
基金supported by the Youth Funds of National Natural Science Foundation of China(No.52004173)the Distinguished Youth Funds of National Natural Science Foundation of China(No.51925402)+2 种基金the Science and Technology Innovation Project of Colleges and Universities in Shanxi Province(No.2020L0066)the China Postdoctoral Science Foundation(No.2022M712922)the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering(Nos.2021SX-TD001 and 2022SXTD008).
文摘To reduce the cost of backfilling coal mining and utilize the underground space of coal mines,a new backfilling mining method with low backfilling rate called constructional backfilling coal mining(CBCM)is proposed.The "backfilling body-immediate roof" cooperative bearing structure of CBCM is analyzed by establishing the model of the medium thick plate on an elastic foundation.The influence of the backfilling rate on the stability of overlying strata is analyzed by the numerical simulation experiment.The control effect of CBCM is verified by a physic similar simulation test.The economic benefit of CBCM is analyzed.The conclusions are:the deformation characteristics of the immediate roof and critical backfilling spacing in CBCM can be analyzed based on the Hu Haichang’s theory.Exerting the bearing capacity of the immediate roof is beneficial to the stability of the overlying strata.The CBCM has a good control effect on the overburden in Xinyang Mine when the backfilling rate is lower than 25%.The backfilling cost of per ton coal is 37.39 yuan/t when the backfilling rate is 13.7%,with a decrease rate of 56.63%than the full-filling.The research results can provide theoretical support for the application of CBCM in coal mining.
文摘AIM:To investigate the efficacy of short-term peginterferon(PEG-IFN)monotherapy for chronic hepatitis C patients who achieved an immediate virological response.METHODS:Defining an"immediate virological response(IVR)"as the loss of serum hepatitis C virus(HCV) RNA 7 d after the first administration of PEG-IFNα,we conducted a 12-wk course of PEG-IFNα2a monotherapy without the addition of ribavirin for 38 patients who had low pretreatment HCV RNA load and exhibited IVR.The patients included 21 men and 17 women,whose ages ranged from 22 to 77 years(mean±SD:52.0±17.8 years).There were 4 patients with HCV genotype 1b,23 patients with genotype 2a and 4 patients with genotype 2b.HCV genotype was not determined for the remaining 7 patients.Patients were categorized into a sustained virological response(SVR)group,if serum HCV RNA remained negative for 24 wk after the end of treatment,or into a relapse group.RESULTS:Based on the intention-to-treat analysis,35 patients(92.1%)achieved SVR.One patient(2.6%)relapsed with serum HCV RNA 12 wk after the end of treatment.Two patients(5.3%)withdrew from the study during the 24-wk follow-up period.With regard to the HCV RNA genotype,the SVR rates were 100%(4/4) for genotype 1b,95.7%(22/23)for genotype 2a and 100%(4/4)for genotype 2b.The SVR rate in 7 patients,whose HCV RNA genotypes were not determined,was 71.4%(5/7).CONCLUSION:Short-term PEG-IFNα2a monotherapy is highly effective for chronic hepatitis C patients who have low pretreatment HCV RNA load and exhibit IVR.
基金Supported by Department of Finance of Jilin Province,No.JCSZ2019378-21 and JCSZ2019378-27Jilin Scientific and Technological Development Program,No.20200201302JC.
文摘BACKGROUND In this case,platelet-rich fibrin(PRF)was added to guided tissue regeneration as a biomaterial in proper order for immediate planting in aesthetic area with periapical infection.CASE SUMMARY With the history of endodontic failure in maxillary central incisor,a 34-year-old female patient required the extraction of maxillary anterior residual root and immediate implantation.Cone beam computed tomography and clinical observation were used to assess the regeneration of soft and bone tissue.Before operation,cone beam computed tomography showed the anterior residual root had serious periapical periodontitis with insufficient labial bone in the aesthetic zone.The patient underwent immediate implant placement and reconstruction of the bone substitution by modified guided bone regeneration.The barrier was a three-layer structure of PRF-collagen membrane-PRF that covered the mixture of PRF and Bio-Oss to promote both osteogenesis and soft tissue healing.At 6 mo postoperatively,the definitive crown was placed after accomplished finial impression.One-year follow-up showed a satisfactory aesthetic effect with no obvious absorption of the labial bone and soft tissue.CONCLUSION The use of PRF in combination with guided bone regeneration can serve as a reliable and simple adjuvant for immediate implanting in infected socket and result in a stable osteogenic effect with good aesthetic outcome.
文摘We introduced the hydrophilic groups to acrylic bone cement to improve compliance and achieve more interdigitation between the bone and the acrylic bone cement in order to create better substrates for immediate loading. FTIR-ATR, contact angle, and maximum breach torque were employed for measurement. The results reveal that the introduction of hydrophilic functional groups has increased PMMA's surface hydrophilicity after contact angle test. FTIR-ATR results suggest the hydrophilic groups participate in the polymerization reactions, and maximum breach torque of the hydrophilic acrylic bone cements is near 110 Ncm torque. Those effects make it possible for conventional acrylic bone cement application in immediate loading of dental implant.
文摘We sought to evaluate immediate and delayed micro-tensile bond strength of Panavia F2.0 and Multilink Sprint resin cement to superficial, deep and cervical dentin. Thirty-six freshly extracted non-carious human molars were sectioned in the mesiodistal direction to expose three different dentin regions including superficial dentin (1 mm below the dentine-enamel junction), deep dentin (1 mm above the highest pulp horn) and cervical dentin (0.5 mm above the cemento-enamel junction and 0.5 mm below the dentine-enamel junction). Resin cements were applied on dentin surfaces and composite blocks were luted under constant seating pressure. Each group was divided into three subgroups according to time intervals. Specimens were sectioned to obtain sticks of 1 mm2 in diameter and subjected to microtensile bond strength testing at a cross head speed of 1 mrn/min. Both resin cements showed higher micro-tensile bond strength to superficial dentin than that to deep or cervical dentin (P 〈 0.001). Micro-ten- sile bond strengths of Panavia F2.0 were higher than those of Multilink Sprint at different dentin regions (P 〈 0.001). Immediate "micro-tensile bond strengths were higher than those of delayed micro-tensile bond strengths for both resin cements (P 〈 0.001). It was concluded that resin cements with different chemical formulations and applications yield significantly different micro-tensile bond strengths to different dentin regions.
文摘In this paper, an EPQ-based inventory policy for an item is presented with stock-dependent demand during two trade credit periods. In addition, there is a provision for 1) an immediate part payment to the wholesaler, 2) borrowing some money from money lending source for the immediate part payment, 3) here supplier or wholesaler offers a trade credit period to his retailer and retailer also offers a trade credit period to his customer. Against the above conjectures inventory model has been formulated with respect to the retailer’s point of view for minimizing the total inventory cost. The non-linear optimization method-Generalized Reduced Gradient (GRG) method is used to find the optimal solutions. Lastly Numerical examples are set to illustrate this model. Finally we use LINGO software to solve this model.