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Comparative efficacy of cementless bipolar hemiarthroplasty and proximal femoral nail anti-rotation in unstable intertrochanteric fractures:A meta-analysis
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作者 Ahmed Mohamed Yousif Mohamed Monzir Salih +10 位作者 Mugahid Mohamed Ayman E Abbas Maysara Elsiddig Moaz Osama Omar Mazin Abdelsalam Basil Elhag Nujud Mohamed Souzan Hassan Eisa Ahmed Samah Ahmed Duaa Mohamed Deena Omar 《World Journal of Orthopedics》 2025年第7期134-145,共12页
BACKGROUND Unstable intertrochanteric fractures in elderly patients require effective surgical management,with both cementless bipolar hemiarthroplasty(CBHA)and proximal femoral nail anti-rotation(PFNA)being valid tre... BACKGROUND Unstable intertrochanteric fractures in elderly patients require effective surgical management,with both cementless bipolar hemiarthroplasty(CBHA)and proximal femoral nail anti-rotation(PFNA)being valid treatment options to reduce morbidity and mortality.AIM To evaluate and compare the outcomes of CBHA and PFNA in treatment of unstable intertrochanteric fractures.METHODS A comprehensive search was conducted to identify relevant studies discussing the outcomes of using both CBH and PFNA in treatment of unstable intertrochanteric fractures.Studies published up to January 1,2025 were searched across multiple databases,including PubMed,EMBASE,Scopus,Web of Science,Cochrane Library,and Google Scholar.Full texts of the selected articles were retrieved,reviewed,and independently assessed by the investigators.Discrepancies were resolved by consensus,with any remaining disagreements being arbitrated by a third author.RESULTS This meta-analysis included three studies,all of which were retrospective,involving a total of 240 patients.The follow-up period for participants was at least 12 months.CBHA was associated with significantly higher blood loss compared to PFNA[mean differences(MD):129.14,95%CI(52.51,205.77),P=0.001],though heterogeneity was high(I²=97%).Operative time showed no significant difference initially[MD:6.10,95%CI(-13.34,25.54),P=0.54],but after excluding one study,BHA had longer operative times[MD:21.51,95%CI(18.60,24.41),P<0.00001].Hospital stay and Harris scores showed no significant differences between groups.CBHA facilitated faster progression to weight-bearing[MD:-11.92,95%CI(-22.46,-1.39),P=0.03]and a lower incidence of prosthetic loosening[risk ratio:0.21,95%CI(0.05,0.92),P=0.04].Refracture and thrombus formation rates were comparable between the two groups.CONCLUSION CBHA offers shorter weight-bearing duration and reduced prosthetic loosening but incurs greater blood loss and longer operative times compared to PFNA.Both techniques show comparable functional recovery,hospital stay,refracture,and thrombus risks.Clinical choice should prioritize early mobilization or surgical minimalism,guided by patient needs.Further prospective studies are warranted. 展开更多
关键词 Cementless bipolar hemiarthroplasty Proximal femoral nail anti-rotation unstable intertrochanteric fractures META-ANALYSIS unstable Functional outcomes FFNA
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Association of Decreased Fecal Microbiota Akkermansia with Increased High-Sensitivity C-Reactive Protein Levels in Patients with Unstable Angina
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作者 Yuan-fan Yuan Ji-yu Zhang +11 位作者 Jia-hao Xu Xin-yi Xia Miao Yu Ling-feng Zha De-sheng Hu Wei-min Wang Chao-long Wang Qing Wang Chen Chen Zhi-lei Shan Fen Yang Xiang Cheng 《Current Medical Science》 2025年第3期494-505,共12页
Background and Objective Inflammation plays a pivotal role in the progression of coronary artery disease(CAD).High-sensitivity C-reactive protein(hsCRP)serves as a well-established biomarker for assessing cardiovascul... Background and Objective Inflammation plays a pivotal role in the progression of coronary artery disease(CAD).High-sensitivity C-reactive protein(hsCRP)serves as a well-established biomarker for assessing cardiovascular inflammation risk.However,the specific intestinal microbiota alteration contributing to increased inflammation remains unclear.Therefore,the present study investigated the correlation between the intestinal microbiota and inflammation in patients with unstable angina(UA).Methods A cohort of 92 patients with UA was recruited for this study.The plasma hsCRP level was measured via a CardioPhase hsCRP assay,fecal samples were collected after admission,and 16S rRNA sequencing was conducted to identify the fecal microbial profile.The participants were classified into two groups according to the median hsCRP level(1.11 mg/L).The composition of the fecal microbiota was compared between patients with hsCRP≥1.11 mg/L and those with hsCRP<1.11 mg/L.Additionally,the correlations between the fecal microbiota and clinical characteristics were analyzed.Results A notable reduction in the relative abundance of Akkermansia was observed in patients with hsCRP≥1.11 mg/L,whereas the diversity of the fecal microbiota was not significantly different between patients with hsCRP≥1.11 mg/L and those with hsCRP<1.11 mg/L.Furthermore,the abundance of Akkermansia was negatively correlated with hsCRP levels.Conclusion This study suggested a significant association between decreased levels of Akkermansia and inflammatory risk in patients with UA.These findings underscore the potential role of the intestinal microbiota in contributing to inflammation in UA patients.Further work is needed on the mechanism by which the microbiota contributes to inflammatory risk. 展开更多
关键词 unstable angina Inflammation risk High-sensitivity C-reactive protein Fecal microbiota Akkermansia
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Factors that influence long term instrumentation stability in patients with unstable thoracolumbar injuries
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作者 Andrey E Bokov Svetlana Y Kalinina +3 位作者 Daria A Kulagina Kseniia S Lopyrina Vladimir V Klinshov Anatolii A Bulkin 《World Journal of Orthopedics》 2025年第8期93-102,共10页
BACKGROUND Pedicle screw fixation is frequently used to treat unstable thoracolumbar injuries;however,the rate of instrumentation failure remains considerable.The primary contributing factor leading to instrumentation... BACKGROUND Pedicle screw fixation is frequently used to treat unstable thoracolumbar injuries;however,the rate of instrumentation failure remains considerable.The primary contributing factor leading to instrumentation failure is poor bone quality.On the other hand,some evidence suggests that surgical tactics can influence long-term instrumentation stability.AIM To assess factors that influence the stability of spinal instrumentation in patients with thoracolumbar injuries.METHODS This study is a non-randomized single center ambispective evaluation of 204 consecutive patients(117 men;87 women)with unstable thoracolumbar injuries.All patients underwent either stand-alone or combined with anterior column reconstruction instrumentation.In cases with spinal cord and nerve root injuries,either posterior or anterior decompression were performed.Patients with pedicle screw loosening were identified via computed tomography imaging.Out of those,cases with clinically significant instrumentation failure were registered.RESULTS The rate of pedicle screw loosening detected by computed tomography was inversely correlated with bone radiodensity figures and an increased association with the number of instrumented levels,residual kyphotic deformity,laminectomy,and lumbosacral fixation.Intermediate screws and anterior reconstruction were associated with a clinically relevant decreased risk of pedicle screw loosening development.Either complete or partial posterior fusion within instrumented levels was capable of decreasing instrumentation failure risk,while extensive decompression with laminectomy and at least one-level total facetectomy were associated with an increased risk of instrumentation failure.Anterior decompression does not have a negative impact on instrumentation stability.CONCLUSION Intermediate screws,anterior reconstruction and posterior tension band preservation are associated with decreased rates of instrumentation instability development.Posterior fusion is beneficial in terms of instrumentation failure prevention. 展开更多
关键词 Instrumentation stability unstable thoracolumbar injuries Pedicle screw loosening Anterior reconstruction Posterior decompression
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Nonlinear Control for Unstable Networked Plants in the Presence of Actuator and Sensor Limitations Using Robust Right Coprime Factorization
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作者 Yuanhong Xu Mingcong Deng 《IEEE/CAA Journal of Automatica Sinica》 2025年第3期516-527,共12页
In this paper,a nonlinear control approach for an unstable networked plant in the presence of actuator and sensor limitations using robust right coprime factorization is proposed.The actuator is limited by upper and l... In this paper,a nonlinear control approach for an unstable networked plant in the presence of actuator and sensor limitations using robust right coprime factorization is proposed.The actuator is limited by upper and lower constraints and the sensor in the feedback loop is subjected to network-induced unknown time-varying delay and noise.With this nonlinear control method,we first employ right coprime factorization based on isomorphism and operator theory to factorize the plant,so that bounded input bounded output(BIBO)stability can be guaranteed.Next,continuous-time generalized predictive control(CGPC)is utilized for the unstable operator of the right coprime factorized plant to guarantee inner stability and enables the closed-loop dynamics of the system with predictive characteristics.Meanwhile,a second-Do F(degrees of freedom)switched controller that satisfies a perturbed Bezout identity and a robustness condition is designed.By using the CGPC controller that possesses predictive behavior and the second-Do F switched stabilizer,the overall stability of the plant subjected to actuator limitations is guaranteed.To address sensor limitations that exist in networked plants in the form of delay and noise which often cause system performance degradation,we implement an identity operator definition in the feedback loop to compensate for these adverse effects.Further,a pre-operator is designed to ensure that the plant output tracks the reference input.Finally,the effectiveness of the proposed design scheme is demonstrated by simulations. 展开更多
关键词 Actuator and sensor limitations identity operator definition network-induced limitations robust right coprime factorization unstable plant
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A numerical study of the three-dimensional flow field with convectively unstable processes
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作者 Qian CAO Changming DONG +5 位作者 Xiaoqian GAO Haili WANG Kenny Thiam Choy LIM KAM SIAN Xiaojie LU Yuli LIU Changshui XIA 《Journal of Oceanology and Limnology》 2025年第4期1056-1074,共19页
Convectively unstable processes caused by dense water subsidence are common occurrences in high-latitude oceanic regions,and significantly modulate mass and heat transport and mixing processes in the ocean.An idealize... Convectively unstable processes caused by dense water subsidence are common occurrences in high-latitude oceanic regions,and significantly modulate mass and heat transport and mixing processes in the ocean.An idealized numerical experiment using the large eddy simulation method was conducted to analyze the three-dimensional flow field structure and the mechanism for dense water subsidence.Specifically,a negative salt flux is set at the sea surface,in which salt flux enters the sea surface to simulate the icing and salting-out phenomena that occur at high latitudes.Results show that the mean-state 3D flow field of dense water subsidence exhibits a hollow conical distribution.The horizontal flow field is characterized by a cyclonic vortex that driven primarily by the pressure gradient and influenced by the Coriolis effect.Moreover,the inverse vertical pressure gradient generated by this vortex inhibits the sinking of the plume,leading to its off-axis deflection and the development of an anticyclonic precession.In addition,the impact of rotation on the structure of a sinking plume within a stratified environment is discussed.Both horizontal vortex intensity and cone angle of the hollow cone flow field are increased with increasing rotation rate,resulting in a decrease in the plume’s maximum sinking depth.Variances in rotation direction cause the horizontal vortex and sinking plumes of dense water in the northern and southern hemispheres to rotate in opposite directions. 展开更多
关键词 convectively unstable process 3D flow field large eddy simulation(LES) rotation rate
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Study on the Clinical Effect of Percutaneous Vertebroplasty in the Treatment of Old Unstable Osteoporotic Spinal Fractures
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作者 Hanpeng Zhang Jiaming Zhang +2 位作者 Shaosong Sun Yajing Wang Fei Gao 《Journal of Clinical and Nursing Research》 2025年第2期108-113,共6页
Objective:To evaluate and analyze the actual efficacy of percutaneous vertebroplasty in the treatment of old unstable osteoporotic spinal fractures.Methods:From March 2023 to March 2024,46 patients with old unstable o... Objective:To evaluate and analyze the actual efficacy of percutaneous vertebroplasty in the treatment of old unstable osteoporotic spinal fractures.Methods:From March 2023 to March 2024,46 patients with old unstable osteoporotic spinal fractures in our hospital were included in this study.They were divided into the conventional group and the observation group based on treatment differences,with 23 patients in each group.The conventional group received conservative drug therapy,while the observation group underwent percutaneous vertebroplasty.The following indicators were compared and analyzed between the two groups:clinical treatment effect and improvement in physical function indicators.Results:The treatment efficiency of the observation group was 95.65%(22/23),while that of the conventional group was 69.57%(16/23).There was a significant difference between the groups,and the treatment effect of the observation group was significantly better(P<0.05).After treatment,the scores of physical status,daily living ability,functional independence,and life obstacles in the observation group were(89.33±4.08),(88.72±4.08),(90.41±2.89),(72.35±3.22),respectively,while those in the conventional group were(68.54±4.21),(67.42±4.11),(73.48±2.75),(72.35±3.22).There was a significant difference between the groups,and the improvement in physical function indicators in the observation group was more pronounced(P<0.05).Conclusion:For patients with old unstable osteoporotic spinal fractures,the basic value of percutaneous vertebroplasty is significant.It can not only improve clinical efficacy and safety but also promote the gradual recovery of patients'physical function indicators.It is recommended for clinical reference and practical application. 展开更多
关键词 Old unstable osteoporotic spinal fractures Percutaneous vertebroplasty Treatment effect
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Unstable evolution of railway slope under the rainfall-vibration joint action 被引量:1
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作者 DONG Haoyu WANG Jiading +2 位作者 ZHANG Dengfei LI Lin XU Yuanjun 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1419-1431,共13页
Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains.However,as two major factors affecting the stability of railway slopes,few s... Understanding the unstable evolution of railway slopes is the premise for preventing slope failure and ensuring the safe operation of trains.However,as two major factors affecting the stability of railway slopes,few scholars have explored the unstable evolution of railway slopes under the joint action of rainfall-vibration.Based on the model test of sandy soil slope,the unstable evolution process of slope under locomotive vibration,rainfall,and rainfall-vibration joint action conditions was simulated in this paper.By comparing and analyzing the variation trends of soil pressure and water content of slope under these conditions,the change laws of pore pressure under the influence of vibration and rainfall were explored.The main control factors affecting the stability of slope structure under the joint action conditions were further defined.Combined with the slope failure phenomena under these three conditions,the causes of slope instability resulting from each leading factor were clarified.Finally,according to the above conclusions,the unstable evolution of the slope under the rainfall-vibration joint action was determined.The test results show that the unstable evolution process of sandy soil slope,under the rainfall-vibration joint action,can be divided into:rainfall erosion cracking,vibration promotion penetrating,and slope instability sliding three stages.In the process of slope unstable evolution,rainfall and vibration play the roles of inducing and promoting slide respectively.In addition,the deep cracks,which are the premise for the formation of the sliding surface,and the violent irregular fluctuation of soil pressure,which reflects the near penetration of the sliding surface,constitute the instability characteristics of the railway slope together.This paper reveals the unstable evolution of sandy soil slopes under the joint action of rainfall-vibration,hoping to provide the theoretical basis for the early warning and prevention technology of railway slopes. 展开更多
关键词 Rainfall vibration joint action Small scale model tests unstable evolution process unstable characteristics Inducing sliding and promoting sliding
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Effects of systematic cardiac rehabilitation training in elderly patients with unstable angina following cardiac stent implantation 被引量:1
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作者 Ling-Ling Yan Xue Yang +1 位作者 Lu Chen Xiao Lu 《World Journal of Clinical Cases》 SCIE 2024年第20期4137-4145,共9页
BACKGROUND Coronary stent implantation is usually used to treat unstable angina to alleviate stenosis or occlusion,promoting blood flow restoration and alleviating symptoms such as myocardial ischemia.And postoperativ... BACKGROUND Coronary stent implantation is usually used to treat unstable angina to alleviate stenosis or occlusion,promoting blood flow restoration and alleviating symptoms such as myocardial ischemia.And postoperative cardiac rehabilitation is essential for enhancing recovery and prognosis.Nevertheless,conventional rehabilitation lacks specificity,particularly for elderly patients with multiple comorbidities and poor compliance,rendering it less effective.AIM To investigate the effects of systematic cardiac rehabilitation training in elderly patients with unstable angina following coronary stenting intervention.METHODS A retrospective enrollment was conducted comprising fifty-four elderly patients with unstable angina pectoris who underwent systematic cardiac rehabilitation training after receiving coronary intervention as the rehabilitation group,while fifty-three elderly patients who received basic nursing and rehabilitation guidance measures after coronary intervention were assigned to the control group.Differences in Seattle Angina Questionnaire scores,survival quality(SF-36)scores,cardiopulmonary exercise function assessment index,echocardiographic cardiac function index,and adverse cardiovascular events were compared between the two groups.RESULTS After intervention,the rehabilitation group observed greater VO2 Max,maximum metabolic equivalent,eft ventricular ejection fraction,left ventricular end-diastolic diameter and smaller left ventricular end-systolic diameter.And the rehabilitation group observed greater scores of physical activity limitation,stable angina pectoris,treatment satisfaction,and SF-36 score.The incidence of adverse cardiovascular events in the two groups,showed no significant difference.CONCLUSION Systematic cardiac rehabilitation following coronary stenting in elderly patients with unstable angina pectoris can enhance cardiac function recovery,consequently enhancing both quality of life and cardiopulmonary exercise tolerance. 展开更多
关键词 Systematicity Cardiac rehabilitation training unstable angina pectoris Coronary stenting implantation Interventional surgery Quality of life Cardiac function Exercise tolerance
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Comparative efficacy of proximal femoral nail vs dynamic condylar screw in treating unstable intertrochanteric fractures 被引量:1
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作者 Ahmed Mohamed Yousif Mohamed Monzir Salih +2 位作者 Mohanad Abdulgadir Ayman E Abbas Duha Lutfi Turjuman 《World Journal of Orthopedics》 2024年第8期796-806,共11页
BACKGROUND Among the most frequent hip fractures are trochanteric fractures,which usually occur from low-energy trauma like minor falls,especially in older people with osteoporotic bones.AIM To evaluate the treatment ... BACKGROUND Among the most frequent hip fractures are trochanteric fractures,which usually occur from low-energy trauma like minor falls,especially in older people with osteoporotic bones.AIM To evaluate the treatment efficacy of dynamic condylar screws(DCS)and proximal femoral nails(PFN)for unstable intertrochanteric fractures.METHODS To find pertinent randomized controlled trials and retrospective observational studies comparing PFN with DCS for the management of unstable femoral intertrochanteric fractures,a thorough search was carried out.For research studies published between January 1996 and April 2024,PubMed,EMBASE,Scopus,Web of Science,Cochrane Library,and Google Scholar were all searched.The complete texts of the papers were retrieved,vetted,and independently examined by two investigators.Disputes were settled by consensus,and any disagreements that persisted were arbitrated by a third author.RESULTS This study included six articles,comprising a total of 173 patients.Compared to the DCS,the PFN had a shorter operation time[mean difference(MD):-41.7 min,95%confidence interval(95%CI):-63.04 to-20.35,P=0.0001],higher success rates with closed reduction techniques[risk ratio(RR):34.05,95%CI:11.12-104.31,P<0.00001],and required less intraoperative blood transfusion(MD:-1.4 units,95%CI:-1.80 to-1.00,P<0.00001).Additionally,the PFN showed shorter fracture union time(MD:-6.92 wk,95%CI:-10.27 to-3.57,P<0.0001)and a lower incidence of reoperation(RR:0.37,95%CI:0.17-0.82,P=0.01).However,there was no discernible variation regarding hospital stay,implant-related complications,and infections.CONCLUSION Compared to DCS,PFN offers shorter operative times,reduces the blood transfusions requirements,achieves higher closed reduction success,enables faster fracture healing,and lowers reoperation incidence. 展开更多
关键词 Intertrochanteric fracture unstable Dynamic condylar screw Proximal femoral nail META-ANALYSIS Comparative study
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Analysis of the Nursing Effect of Continuity of Care on Elderly Patients with Coronary Heart Disease Unstable Angina and its Impact on Quality of Life 被引量:2
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作者 Ling Yan 《Journal of Clinical and Nursing Research》 2024年第2期185-190,共6页
Objective:To analyze the effect of using continuity of care for elderly patients with coronary heart disease(CHD)with unstable angina pectoris(UAP)and its impact on their quality of life.Methods:100 cases of elderly p... Objective:To analyze the effect of using continuity of care for elderly patients with coronary heart disease(CHD)with unstable angina pectoris(UAP)and its impact on their quality of life.Methods:100 cases of elderly patients with CHD with UAP admitted to our hospital from March 2022 to March 2023 were selected and grouped into an observation group and a control group of 50 cases each according to the randomized number table method.The nursing effect and quality of life of the observation group(continuity nursing)and the control group(routine nursing)were compared.Results:The total effective rate of nursing care was 96.00%observation group and 80.00%for the control group,and the differences were significant(χ2=6.061,P<0.05).Patients in the observation group had fewer episodes(1.42±0.21)times/week and a shorter duration(5.46±0.39)min,which were better than the control group(t=3.465,2.973;P<0.05).The depression self-rating depression scale(SDS)score(42.16±6.64)and anxiety self-rating scale(SAS)score(32.26±7.35)in the observation group were lower and the quality of life was higher as compared to that of the control group(P<0.05).Conclusion:Continuous nursing care improved the nursing effect of elderly CHD with UAP patients,promoted the alleviation of UAP symptoms,improved patient mentality,and improved their quality of life.Hence,continuous nursing care possesses significant clinical application value. 展开更多
关键词 Continuity of care ELDERLY Coronary heart disease unstable angina Nursing outcomes Quality of life
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PFNA2 versus 95 Degree Condylar Blade Plate in the Management of Unstable Trochanteric Fractures
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作者 Piyush Gadegone Wasudeo Gadegone +1 位作者 Vijayanand Lokhande Virender Kadian 《Open Journal of Orthopedics》 2024年第2期93-104,共12页
Purpose: The proximal femoral nail anti-rotation (PFNA) is known to have advantages in enhancing the anchorage ability of internal fixation in elderly unstable osteoporotic intertrochanteric fracture patients. However... Purpose: The proximal femoral nail anti-rotation (PFNA) is known to have advantages in enhancing the anchorage ability of internal fixation in elderly unstable osteoporotic intertrochanteric fracture patients. However whether it is superior to condylar blade fixation is not clear. This study aimed to determine which treatment has better clinical outcomes in older patients. Materials and Methods: A total of 86 patients over the age of 60 with unstable trochanteric fractures within the past 3 weeks, were included in this prospective study conducted from June 1, 2018, to May 31, 2021. All the intertrochanteric fractures were classified according to AO/OTA classification. Among them, 44 cases were treated with the Proximal Femoral Nail (PFNA2) with or without an augmentation screw, and 42 cases were treated with the Condylar Blade Plate. In addition, the operative time, intraoperative blood loss, intraoperative and postoperative blood transfusion, postoperative weight-bearing time, hospitalization time, Harris score of hip function, Kyle’s criteria and postoperative complications were compared between the two groups. Results: The mean duration of surgery for the PFN group was 66.8 minutes (on average), whereas for the condylar blade plate group, it was 99.30 minutes (on average). The PFNA2 group experienced less blood loss (average of 80 mL) compared to the condylar blade plate group (average of 120 mL). Union and partial weight-bearing occurred earlier in the PFNA2 group (14.1 weeks and 10.6 weeks, respectively) compared to the Condylar blade plate group (18.7 weeks and 15.8 weeks). In two patients from the PFNA2 group, screw backing out and varus collapse complications were encountered;however, these patients remained asymptomatic and did not require revision surgery. In two other patients, screw cut out and breakage of the nail at the helical screw hole leading to non-union of the proximal femur were observed during the nine-month follow-up, necessitating revision surgery with prosthetic replacement. Among the condylar blade plate group, three patients experienced complications, including blade breakage at the blade and plate junction. In two cases, the fracture united in varus, and in one case, the blade cut through, resulting in non-union of the femoral head, which required revision surgery. According to the Harris hip score and Kyle’s criteria, a good-excellent outcome was observed in 92.85% of cases in the PFNA2 group and 90.90% of cases in the condylar blade plate group. Conclusion: Both the Proximal Femoral Nail A2 and Condylar blade plate are effective implants for the treatment of unstable trochanteric fractures. The intramedullary implant promotes biological healing and allows for early ambulation with minimal complications. Similarly satisfactory restoration of anatomy and favorable radiological and functional results can be achieved with the biological fixation provided by the 95-degree condylar blade plate. However, the use of PFNA2 internal fixation technique has the advantage of less trauma in elderly patients than the 95-degree condylar blade plate. 展开更多
关键词 Proximal Femoral Nail Anti-Rotation Condylar Blade Plate Internal Fixation unstable Intertrochanteric Fracture OSTEOPOROTIC
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Singular Points, Closed Orbits, Stable Manifolds and Unstable Manifolds of Second Order Autonomous Birkhoff Systems 被引量:1
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作者 陈向炜 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1998年第4期330-336,共7页
Aim To study singular points, closed orbits, stable manifolds and unstable manifolds of a second order autonomous Birkhoff system. Methods Qualitative methods of ordinary differential equation were used. Results and ... Aim To study singular points, closed orbits, stable manifolds and unstable manifolds of a second order autonomous Birkhoff system. Methods Qualitative methods of ordinary differential equation were used. Results and Conclusion The criteria for singular points, closed orbits and hyperbolic equilibrium points of a second order autonomous Birkhoff system are given. Moreover the stability of equilibria, stable manifolds and unstable manifolds are obtained. 展开更多
关键词 Birkhoff system singular point closed orbit stable manifold unstable manifold
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New Exact Traveling Wave Solutions of the Unstable Nonlinear Schrdinger Equations 被引量:5
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作者 K.Hosseini D.Kumar +1 位作者 M.Kaplan E.Yazdani Bejarbaneh 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第12期761-767,共7页
The present paper studies the unstable nonlinear Schr¨odinger equations, describing the time evolution of disturbances in marginally stable or unstable media. More precisely, the unstable nonlinear Schr¨odin... The present paper studies the unstable nonlinear Schr¨odinger equations, describing the time evolution of disturbances in marginally stable or unstable media. More precisely, the unstable nonlinear Schr¨odinger equation and its modified form are analytically solved using two efficient distinct techniques, known as the modified Kudraysov method and the sine-Gordon expansion approach. As a result, a wide range of new exact traveling wave solutions for the unstable nonlinear Schr¨odinger equation and its modified form are formally obtained. 展开更多
关键词 unstable nonlinear SchrSdinger equation modified unstable nonlinear Schrodinger equation mod-ified Kudryashov method sine-Gordon expansion approach new exact traveling wave solutions
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A method for prediction of unstable deformation in hot forging process by simulation
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作者 鲁世强 李鑫 +2 位作者 王克鲁 刘诗彪 傅铭旺 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3739-3747,共9页
A method is proposed for prediction of the unstable deformation in hot forging process using both the determined thermomechnical parameter windows of the unstable deformation zones and finite element simulation. Takin... A method is proposed for prediction of the unstable deformation in hot forging process using both the determined thermomechnical parameter windows of the unstable deformation zones and finite element simulation. Taking Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy as the testing material, the thermomechnical parameter windows of the unstable deformation zones for the Ti-alloy are integrated into a commercial finite element simulation software platform. The distribution and variation of the unstable deformation zones of the alloy in hot compression process are simulated and predicted using the tailor-made finite element codes in the finite element platform. The simulation results tally with the physical experiments and the proposed method for simulation and prediction of the unstable deformation is thus verified and its efficiency is validated. 展开更多
关键词 instability map unstable deformation instability deformation simulation Ti-6.5Al-3.5Mo-1.5Zr-0.3Si titanium alloy
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Oscillation of Unstable Second Order Neutral Differential Equations with Positive and Negative Coefficients
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作者 徐继军 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第3期72-75,共4页
This paper discusses a class of unstable second order neutral differential equations with positive and negative coeffcients. Sufficient conditions for all bounded solutions of the equations to be oscillatory are obtai... This paper discusses a class of unstable second order neutral differential equations with positive and negative coeffcients. Sufficient conditions for all bounded solutions of the equations to be oscillatory are obtained. 展开更多
关键词 neutral equation unstable OSCILLATION
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Danshenchuanxiongqin injection in the treatment of unstable angina pectoris: a systematic review and Meta-analysis 被引量:27
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作者 Zhang Xiaomeng Wu Jiarui +1 位作者 Zhang Bing Zhou Wei 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2016年第2期144-150,共7页
OBJECTIVE:To evaluate systematically the efficacy and safety of Danshenchuanxiongqin Injection(DCI)in the treatment of unstable angina pectoris(UAP).METHODS:Randomized controlled trials(RCTs)regarding DCI used for tre... OBJECTIVE:To evaluate systematically the efficacy and safety of Danshenchuanxiongqin Injection(DCI)in the treatment of unstable angina pectoris(UAP).METHODS:Randomized controlled trials(RCTs)regarding DCI used for treating UAP were searched in English and Chinese electronic databases from inception to January 2014.Two reviewers independently retrieved RCTs and extracted relevant information.The Cochrane risk of bias method was used to assess the quality of included studies,and a Meta-analysis was conducted with Review Manager5.2 software.RESULTS:Eleven RCTs involving 1034 participants were included.The methodological quality was relatively passable.The Meta-analysis indicated that the combined use of DCI and conventional treatment with Western Medicine(WM)was more efficacious in the outcomes of total effective rate[Relative Risk(RR)=1.27,95%CI(confidence interval;1.18,1.35),P<0.000 01],the total effective rate of ECG[RR=1.40,95%CI(1.18,1.66),P<0.000 01],total cholesterol[Mean difference(MD)=-0.58,95%CI(-0.83,-0.33),P<0.000 01],total triglycerides[MD=-0.36,95%CI(-0.54,-0.17),P=0.0001],and the number of ST-segment depression[MD=-0.36,95%CI(-0.54,-0.17),P=0.0001].There were two adverse drug reactions reported in one study.CONCLUSION:Based on the systematic review,DCI combined with WM appeared to be efficacious in the treatment UAP.However,the evidence of DCI for treating UAP requires large-scale and double-blind RCTs to substantiate these findings. 展开更多
关键词 Danshenchuanxiongqin injection An gina unstable REVIEW META-ANALYSIS
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Seismological method for prediction of areal rockbursts in deep mine with seismic source mechanism and unstable failure theory 被引量:23
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作者 唐礼忠 XIA K W 《Journal of Central South University》 SCIE EI CAS 2010年第5期947-953,共7页
The research on the rock burst prediction was made on the basis of seismology,rock mechanics and the data from Dongguashan Copper Mine(DCM) ,the deepest metal mine in China.The seismic responses to mining in DCM were ... The research on the rock burst prediction was made on the basis of seismology,rock mechanics and the data from Dongguashan Copper Mine(DCM) ,the deepest metal mine in China.The seismic responses to mining in DCM were investigated through the analyses of the spatio-temporal distribution of hypocenters,apparent stress and displacement of seismic events,and the process of the generation of hazardous seismicity in DCM was studied in the framework of the theory of asperity in the seismic source mechanism.A method of locating areas with hazardous seismicity and a conceptual model of hazardous seismic nucleation in DCM were proposed.A criterion of rockburst prediction was analyzed theoretically in the framework of unstable failure theories,and consequently,the rate of change in the ratio of the seismic stiffness of rock in a seismic nucleation area to that in surrounding area,dS/dt,is defined as an index of the rockburst prediction.The possibility of a rockburst will increase if dS/dt>0,and the possibility of rock burst will decrease if dS/dt<0.The correctness of these methods is demonstrated by analyses of rock failure cases in DCM. 展开更多
关键词 areal rockburst prediction seismic source mechanism unstable failure deep mine seismic stiffness seismic nucleation
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What are the best Salvia miltiorrhiza injection classes for treatment of unstable angina pectoris? A systematic review and network Meta-analysis 被引量:12
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作者 Liu Shi Wu Jiarui +1 位作者 Zhang Dan Tan Di 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2018年第3期321-338,共18页
OBJECTIVE: To undertake a systematic review and network meta-analysis(NMA) to compare the effectiveness among the different regimens of Salvia miltiorrhiza injection classes(SMICs) for unstable angina pectoris(UAP) tr... OBJECTIVE: To undertake a systematic review and network meta-analysis(NMA) to compare the effectiveness among the different regimens of Salvia miltiorrhiza injection classes(SMICs) for unstable angina pectoris(UAP) treatment.METHODS: A systematic retrieval was conducted in several literature databases to identify randomized controlled trials focusing on the different regimens of SMICs for UAP treatment until January2016. The quality assessment was accomplished according to the Cochrane risk of bias tool. Pair-wise meta-analyses were carried out by Rev Man 5.3. A random-effects model of NMA was used to compare the different regimens of SMICs with regard to efficacy by STATA 13.0.RESULTS: A total of 111 studies involving 10 500patients were included in the NMA. The methodological quality of included studies was not high.Current evidence shows that salvianolate(SI) is the optimal treatment for UAP in improving the total efficacy against UAP. Guanxingning(GXN) is the optimal treatment for UAP for improving the total effectiveness of electrocardiography.CONCLUSION: SMICs have advantages in preventing cardiovascular events. GXN, SI, and Danhong had the greatest probability of being the best treatment in the total efficacy against UAP and for improving the total effectiveness of electrocardiography. 展开更多
关键词 SALVIA miltiorrhiza ANGINA unstable Re-view Network META-ANALYSIS
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MmWave Beamforming for UAV Communications with Unstable Beam Pointing 被引量:8
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作者 Weizhi Zhong Lei Xu +2 位作者 Qiuming Zhu Xiaomin Chen Jianjiang Zhou 《China Communications》 SCIE CSCD 2019年第1期37-46,共10页
Millimeter wave(mmWave) communications of unmanned aerial vehicles(UAVs) have drawn dramatic attentions for its flexibility on a variety of applications.Recently,channel tracking base on the spatial features has been ... Millimeter wave(mmWave) communications of unmanned aerial vehicles(UAVs) have drawn dramatic attentions for its flexibility on a variety of applications.Recently,channel tracking base on the spatial features has been proposed to solve the problem of beam misalignments due to the UAV navigation.However,unstable beam pointing caused by the non-ideal beam tracking environment may impact the performance of mmWave systems significantly.In this paper,an improved beamforming method is presented to overcome this shortcoming.Firstly,the effect of the beam deviation is analyzed through the establishment of the equivalent data rate.Then,combining the quantification of spatial angle and the improved orthogonal matching pursuit(OMP) algorithm,an optimized beam corresponding to the beam deviation is obtained.Simulation results show that the optimized beam of the proposed approach can effectively improve the spectral efficiency without improving the complexity when the beam pointing is unstable. 展开更多
关键词 UAV COMMUNICATIONS mmWave BEAMFORMING unstable BEAM POINTING BEAM tracking orthogonal matching pursuit(OMP)
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Identifying Metabolite and Protein Biomarkers in Unstable Angina In-patients by Feature Selection Based Data Mining Method 被引量:8
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作者 SHI Cheng-he ZHAO Hui-hui +8 位作者 HOU Na CHEN Jian-xin SHI Qi XU Xue-gong WANG Juan ZHENG Cheng-long ZHAO Ling-yan YANG Yi WANG Wei 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第1期87-93,共7页
Unstable angina(UA) is the most dangerous type of Coronary Heart Disease(CHD) to cause more and more mortal and morbid world wide. Identification of biomarkers for UA at the level of proteomics and metabolomics is... Unstable angina(UA) is the most dangerous type of Coronary Heart Disease(CHD) to cause more and more mortal and morbid world wide. Identification of biomarkers for UA at the level of proteomics and metabolomics is a better avenue to understand the inner mechanism of it. Feature selection based data mining method is better suited to identify biomarkers of UA. In this study, we carried out clinical epidemiology to collect plasmas of UA in-patients and controls. Proteomics and metabolomics data were obtained via two-dimensional difference gel electrophoresis and gas chromatography techniques. We presented a novel computational strategy to select biomarkers as few as possible for UA in the two groups of data. Firstly, decision tree was used to select biomarkers for UA and 3-fold cross validation was used to evaluate computational performanees for the three methods. Alternatively, we combined inde- pendent t test and classification based data mining method as well as backward elimination technique to select, as few as possible, protein and metabolite biomarkers with best classification performances. By the method, we selected 6 proteins and 5 metabolites for UA. The novel method presented here provides a better insight into the pathology of a disease. 展开更多
关键词 BIOMARKER Metabolomics PROTEOME Feature selection Data mining unstable angina
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