The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, int...The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, intuitive and enable an initial interpretation of the results. On the other hand, in TEM method the apparent resistivity values are not very intuitive and interpretation based only on the apparent resistivity values cannot be done reasonably. In this way, this paper presents a discussion about the reasons and effects of the negatives values of apparent resistivity in TEM soundings. The main objective of this paper is to clarify the meanings of these negatives values and the possible effects in TEM inversion.展开更多
Background: China is facing with a crisis of the aging population. After the implementation of the latest fertility policy, the research on fertility related issues is urgent. Objective: The objective of this study is...Background: China is facing with a crisis of the aging population. After the implementation of the latest fertility policy, the research on fertility related issues is urgent. Objective: The objective of this study is to explore the fertility values among women of childbearing age and the socio-demographic factors associated with it under the background of three-child policy, which is helpful to cope with the aging of the population. Methods: This study was conducted among 383 women of childbearing age who met the inclusion criteria using a general information questionnaire and the fertility values questionnaire from May to August 2021 in Hunan Province, China. Data were collected on the women’s socio-demographic characteristics and fertility values. The descriptive statistics, t-test and analysis of variance were used for data analysis. Results: The total mean score of the positive values was 43.55 ± 10.10, and that of the negative values was 50.87 ± 13.85. There were significant differences in the scores of the overall positive and negative values, as well as scores of each dimension (p The item mean score of the overall negative values (3.38 ± 0.93) was higher than that of the overall positive values (2.90 ± 0.67). Among the positive values, “emotional value” (4.26 ± 0.93) scored the highest, while “worrying about life changes” (3.88 ± 1.10) scored the highest among the negative values. There were significant differences in both the positive and negative values in terms of age, marital status, and “only-child” women or not (p Conclusion: The fertility values among women of childbearing age in Hunan Province were relatively negative, especially, excessive worries about life change since having a child, which may lead to further declines in fertility levels. Relevant support measures are urgently needed from the government to adapt to the three-child policy.展开更多
Objective:Sentinel lymph node biopsy(SLNB)is currently the standard of care in clinically node negative(cN0)breast cancer.The present study aimed to evaluate the negative predictive value(NPV)of 18F-FDG dedicated lymp...Objective:Sentinel lymph node biopsy(SLNB)is currently the standard of care in clinically node negative(cN0)breast cancer.The present study aimed to evaluate the negative predictive value(NPV)of 18F-FDG dedicated lymph node positron emission tomography(LymphPET)in cN0 patients.Methods:This was a prospective phase II trial divided into 2 stages(NCT04072653).In the first stage,cN0 patients underwent axillary LymphPET followed by SLNB.In the second stage,SLNB was omitted in patients with a negative preoperative axillary assessment after integration of LymphPET.Here,we report the results of the first stage.The primary outcome was the NPV of LymphPET to detect macrometastasis of lymph nodes(LN-macro).Results:A total of 189 patients with invasive breast cancer underwent LymphPET followed by surgery with definitive pathological reports.Forty patients had LN-macro,and 16 patients had only lymph node micrometastasis.Of the 131 patients with a negative LymphPET result,16 patients had LN-macro,and the NPV was 87.8%.After combined axillary imaging evaluation with ultrasound and LymphPET,100 patients were found to be both LymphPET and ultrasound negative,9 patients had LN-macro,and the NPV was 91%.Conclusions:LymphPET can be used to screen patients to potentially avoid SLNB,with an NPV>90%.The second stage of the SOAPET trial is ongoing to confirm the safety of omission of SLNB according to preoperational axillary evaluation integrating LymphPET.展开更多
Current histopathological staging procedures in colorectal cancer(CRC)depend on midline division of the lymph nodes(LNs)with one section of hematoxylin and eosin staining.Cancer cells outside this transection line may...Current histopathological staging procedures in colorectal cancer(CRC)depend on midline division of the lymph nodes(LNs)with one section of hematoxylin and eosin staining.Cancer cells outside this transection line may be missed,which could lead to understaging of Union for International Cancer Control Stage II high-risk patients.The one-step nucleic acid amplification(OSNA)assay has emerged as a rapid molecular diagnostic tool for LN metastases detection.It is a molecular technique that can analyze the entire LN tissue using a reversetranscriptase loop-mediated isothermal amplification reaction to detect tumorspecific cytokeratin 19 mRNA.Our findings suggest that the OSNA assay has a high diagnostic accuracy in detecting metastatic LNs in CRC and a high negative predictive value.OSNA is a standardized,observer-independent technique,which may lead to more accurate staging.It has been suggested that in stage II CRC,the upstaging can reach 25%and these patients can access postoperative adjuvant chemotherapy.Moreover,intraoperative OSNA sentinel node evaluation may allow early CRC to be treated with organ-preserving surgery,while in more advanced-stage disease,a tailored lymphadenectomy can be performed considering the presence of aberrant lymphatic drainage and skip metastases.展开更多
Aim: To assess the predictive value of the Baveno VI criteria for the diagnosis of large esophageal varices (EV) in Black African patient with compensated hepatitis B related cirrhosis. Methods: We carried out a cross...Aim: To assess the predictive value of the Baveno VI criteria for the diagnosis of large esophageal varices (EV) in Black African patient with compensated hepatitis B related cirrhosis. Methods: We carried out a cross-sectional study from January 2 to July 3 (2016), in Department of Gastroenterology at University Hospitals of Cocody (CHUC) and Yopougon (CHUY). All the black African patients included were more than 15 years old and their liver elasticity score (LES) was carried out at Yopougon University Hospital. Hepatitis B related cirrhosis was defined by LES ≥ 11 kPa (FibroScan? (Echosens, France)) with positive HBs antigen (HBsAg) and anti HBc antibody. All the patients with hepatitis B related cirrhosis performed a gastroscopy at Cocody University Hospital and esophageal varices were ranked according to société fran?aise d’endoscopie digestive (SFED) classification. Data analysis was performed by SPSS model 20.0 statistics software (SPSS Inc., Chicago, IL, United States). Diagnostic performance of LES 150,000/mmm3 (Baveno VI criteria) for the diagnosis of large EV by gastroscopy was studied (area under the ROC curve, specificity (Sp), sensitivity (Se), positive predictive value (PPV) and negative predictive value (NPV). Results: During the study period, 720 patients achieved liver FibroScan? at CHUY. Of these, 60 respondents to our inclusion criteria were prospectively included in our study. Twelve (20%) of these 60 patients met the Baveno VI criteria. EV were present in 40% of cases (n = 24) with 6.7% (n = 4), 15% (n = 9) and 18.3% (n = 11) of grade 1, 2 and 3, respectively. (66.7% (n = 40) without EV or with small EV) and 33.3% (n = 20) with large EV. The Baveno VI criteria had a Se, Sp, PPV and NPV of 100%, 41.6%, 30% and 100% respectively for the diagnosis of large EV. The area under the ROC curve of a platelet count greater than 150,000/mm3, a liver elasticity score of less than 20 kPa and combination of both were respectively 0.763 [0.645 - 0.880;P = 0.272];0.588 [0.436 - 0.739;P = 0.01] and 0.650 [0.513 - 0.787 P = 0.005]. Conclusion: The combination of liver elasticity score 150,000/mm3, allowed the exclusion of large esophageal varices at gastroscopy with a 100 % NPV in Black African patients with compensated hepatitis B related cirrhosis.展开更多
Objective:To explore the candidate indications for function-preserving curative gastrectomy and sentinel lymph node navigation surgery in early gastric cancer(EGC).Methods:The clinicopathological data of 561 patients ...Objective:To explore the candidate indications for function-preserving curative gastrectomy and sentinel lymph node navigation surgery in early gastric cancer(EGC).Methods:The clinicopathological data of 561 patients with EGC who underwent radical gastrectomy for gastric cancer at Peking University Cancer Hospital from November 2010 to November 2020 with postoperative pathological stage pT1 and complete examination data,were collected.Pearson’s Chi-square test was used and binary logistic regression was employed for univariate and multivariate analyses.Combined analysis of multiple risk and protective factors for lymph node metastasis(LNM)of EGC was performed.A negative predictive value(NPV)combination model was built and validated.Results:LNM occurred in 85 of 561 patients with EGC,and the LNM rate was 15.15%.NPV for LNM reached 100%based on three characteristics,including ulcer-free,moderately well differentiation and patient<65years old or tumor located at the proximal 1/3 of the stomach.Regarding lymphatic basin metastasis,multivariate analysis showed that the metastatic proportion of the left gastric artery lymphatic basin was significantly higher in male patients compared with female patients(65.96%vs.38.89%,P<0.05).The proportion of right gastroepiploic artery lymphatic basin metastasis in patients with a maximum tumor diameter>2 cm was significantly greater than that noted in patients with a maximum tumor diameter≤2 cm(60.78%vs.28.13%,P<0.05).Conclusions:Characteristics of lymph node stations/basins metastasis will facilitate precise lymph node resection.The NPV for LNM reaches 100%based on the following two conditions:young and middle-aged EGC patients,well-differentiated tumors,and without ulcers;or well-differentiated tumors,without ulcers,and tumors located in the proximal stomach.These findings can be used as the recommended indications for functionpreserving curative gastrectomy and sentinel lymph node navigation surgery.展开更多
The Daqing oilfield is a multilayered heterogeneous oil field where the pressure are different in the same vertical profile causing many troubles to the adjustment well drillings. The approximately-balanced drilling t...The Daqing oilfield is a multilayered heterogeneous oil field where the pressure are different in the same vertical profile causing many troubles to the adjustment well drillings. The approximately-balanced drilling technique has been developed and proved to be efficient and successful in Daqing oilfield. This paper discusses the application of approximately-balanced drilling technique under the condition of multilayered pressure in Daqing oilfield, including the prediction of formation pressure, the pressure discharge technique for the drilling well and the control of the density of drilling fluid.展开更多
Objective： This study compared the performance of the immunochromatographic strip （ICS） to the Venereal Disease Research Laboratory （VDRL） test and Treponema pallidum haemagglutination assay （TPHA） at a primary...Objective： This study compared the performance of the immunochromatographic strip （ICS） to the Venereal Disease Research Laboratory （VDRL） test and Treponema pallidum haemagglutination assay （TPHA） at a primary health care setting. Methods： The study group was comprised of 150 females randomly drawn from a population of pregnant women attending their first antenatal visit or follow-up visits at West Maternity Hospital in Eldoret Kenya, but without a previous syphilis test during that pregnancy. On-site VDRL, ICS and TPHA tests were performed and immediate treatment provided where appropriate. The performance of the three tests was compared, Results： The sero-prevalence of syphilis as determined by the VDRL test was 3%. There was no significant difference between the ICS and the VDRL test （P 〉 0.05）. The sensitivity and specificity of the ICS test were 80% and 98.6% respectively, while the negative predictive value （NPV） and positive predictive value （PPV） were both 100%. On the other hand, the sensitivity and specificity of the VDRL test were 66.7% and 99.3%, while the NPV and PPV were 80% and 98.6% respectively. The Treponema pallidum haemagglutination assay was used as a reference test and had sensitivity, specificity, NPV and PPV of 100%. Conclusion： The diagnostic accuracy of the ICS compared favorably with theVDRL gold standard. The use of the ICS in Kenya can improve the diagnosis of syphilis in health facilities both with and without laboratories and allow community health care workers to make a rapid diagnosis of the disease, and consequently make immediate therapeutic decisions.展开更多
"3R" principle circular economy emphasizes the technical operation level,while the theoretical viewpoint on value-increasing of circular economy makes deep analysis based on environmental economics. The view..."3R" principle circular economy emphasizes the technical operation level,while the theoretical viewpoint on value-increasing of circular economy makes deep analysis based on environmental economics. The viewpoint takes for that the evaluation of any circular economic model should consider both the economic value and externalities. If the material units unattached to products in the economic system are circulated with value-increasing as more as possible,more value can be created with lower consumption of resources. The essential principle of circular economy is that the material units within an economic system should go through the multiple production to be circulated with value-increasing,the main purpose of circular economy is that the material units shouldn't attach to waste going out of the system as much as possible in order to reduce pollution emissions,the economic mechanism of circular economy is that the economic value chain should be used to pull the material units of the system to achieve smooth circulation.展开更多
Introduction: Helicobacter pylori is a gram-negative bacillus responsible for numerous gastroduodenal pathologies, and this infection is a public health problem. The prevalence of infection with this bacterium remains...Introduction: Helicobacter pylori is a gram-negative bacillus responsible for numerous gastroduodenal pathologies, and this infection is a public health problem. The prevalence of infection with this bacterium remains high in countries with limited resources. Diagnosis relies mainly on numerous invasive and noninvasive methods. The aim of this work was to evaluate the different indirect diagnostic methods using bacterial cultures. Methods: We conducted a cross-sectional and analytical study from January to May 2022 in the gastroenterology departments of Douala General Hospital and Douala Military Hospital. All patients aged 18 years and older who were in the gastroenterology consultation and agreed to participate were included in our study. Sociodemographic, clinical, and paraclinical data were collected. Urease, liquid urea, and culture tests were performed from the specimens obtained by fibroscopy. Serological tests were performed on the blood sample. Results: 101 patients were included, 58 were female and 43 were male, for a sex ratio of 1.3. The mean age was 44.2 ± 16 years. The prevalence of infection was 90.5%, 44.1%, 40.6% and 21.8% for serology, direct microbiological examination, RUT (rapid urea test) and culture, respectively. Comparison of the different tests showed sensitivity and specificity of 67.1% and 64%, respectively, for RUT, 100% and 73.7%, respectively, for direct microbiological examination, and 100% and 14.8%, respectively, for serology. The positive and negative predictive values were 39.5% and 100% for serology, 39% and 85% for RUT, and 55.6% and 100% for direct microbiological examination, respectively. Conclusion: The prevalence of Helicobacter pylori infection depends on the type of test used. Direct examination is more reliable than RUT and serology.展开更多
Background: Multiplex virus assays are useful in immunocompromised hosts but still challenging in routine clinical settings in terms of their sensitivity, specificity, reproducibility, and time and cost performances. ...Background: Multiplex virus assays are useful in immunocompromised hosts but still challenging in routine clinical settings in terms of their sensitivity, specificity, reproducibility, and time and cost performances. In recent years, we developed a qualitative multiplex virus PCR assay capable of the simultaneous detection of 13 virus species within 3 h. However, because of the multiple and concomitant nature of this virus assay, it should be validated for qualitative reliability. Materials and Methods: As a preclinical examination, this multiplex PCR was able to detect 1.25 × 10<sup>3</sup> copies/mL of 13 synthesized virus genomes and preserved same virus DNAs by the serial dilution method. Blood samples from 40 patients who underwent hematopoietic stem cell transplantation were then examined by multiplex PCR for 13 virus species, followed by quantitative real-time PCR for all 13 virus species as reference PCR when these patients developed symptoms suggestive of viral infection. Results: In 421 cumulative qualitative-quantitative tests, the multiplex PCR certainly detected 1.0 × 103 copies/mL of 5 viruses (CMV, JCV, BKV, HHV-6, ADV) that were frequently detected and thus reasonably analyzed. The positive and negative predictive values of multiplex PCR were 84.2% - 93.3% and 90.7% - 99.0%, respectively, and sensitivity and specificity were 59.0% - 83.3% and 97.2% - 99.2%, respectively, for these 5 viruses. Conclusion: From these performances, the multiplex PCR assay may be acceptable in a routine clinical laboratory setting.展开更多
We investigated the false-negative,true-negative,false-positive,and true-positive predictive values from a general group testing procedure for a heterogeneous population.We show that its false(true)-negative predictiv...We investigated the false-negative,true-negative,false-positive,and true-positive predictive values from a general group testing procedure for a heterogeneous population.We show that its false(true)-negative predictive value of a specimen is larger(smaller),and the false(true)-positive predictive value is smaller(larger)than that from individual testing procedure,where the former is in aversion.Then we propose a nested group testing procedure,and show that it can keep the sterling characteristics and also improve the false-negative predictive values for a specimen,not larger than that from individual testing.These characteristics are studied from both theoretical and numerical points of view.The nested group testing procedure is better than individual testing on both false-positive and false-negative predictive values,while retains the efficiency as a basic characteristic of a group testing procedure.Applications to Dorfman’s,Halving and Sterrett procedures are discussed.Results from extensive simulation studies and an application to malaria infection in microscopy-negative Malawian women exemplify the findings.展开更多
文摘The calculation of apparent resistivity in electrical methods is relatively simple and consolidated in the literature. Furthermore, in the case of DC methods, the apparent resistivity values are for the most part, intuitive and enable an initial interpretation of the results. On the other hand, in TEM method the apparent resistivity values are not very intuitive and interpretation based only on the apparent resistivity values cannot be done reasonably. In this way, this paper presents a discussion about the reasons and effects of the negatives values of apparent resistivity in TEM soundings. The main objective of this paper is to clarify the meanings of these negatives values and the possible effects in TEM inversion.
文摘Background: China is facing with a crisis of the aging population. After the implementation of the latest fertility policy, the research on fertility related issues is urgent. Objective: The objective of this study is to explore the fertility values among women of childbearing age and the socio-demographic factors associated with it under the background of three-child policy, which is helpful to cope with the aging of the population. Methods: This study was conducted among 383 women of childbearing age who met the inclusion criteria using a general information questionnaire and the fertility values questionnaire from May to August 2021 in Hunan Province, China. Data were collected on the women’s socio-demographic characteristics and fertility values. The descriptive statistics, t-test and analysis of variance were used for data analysis. Results: The total mean score of the positive values was 43.55 ± 10.10, and that of the negative values was 50.87 ± 13.85. There were significant differences in the scores of the overall positive and negative values, as well as scores of each dimension (p The item mean score of the overall negative values (3.38 ± 0.93) was higher than that of the overall positive values (2.90 ± 0.67). Among the positive values, “emotional value” (4.26 ± 0.93) scored the highest, while “worrying about life changes” (3.88 ± 1.10) scored the highest among the negative values. There were significant differences in both the positive and negative values in terms of age, marital status, and “only-child” women or not (p Conclusion: The fertility values among women of childbearing age in Hunan Province were relatively negative, especially, excessive worries about life change since having a child, which may lead to further declines in fertility levels. Relevant support measures are urgently needed from the government to adapt to the three-child policy.
基金supported by the Ministry of Education Innovation Team(Grant No.IRT1223)and the Shanghai Health System Joint Project of Key Disease(Grant No.2013ZYJB0302).
文摘Objective:Sentinel lymph node biopsy(SLNB)is currently the standard of care in clinically node negative(cN0)breast cancer.The present study aimed to evaluate the negative predictive value(NPV)of 18F-FDG dedicated lymph node positron emission tomography(LymphPET)in cN0 patients.Methods:This was a prospective phase II trial divided into 2 stages(NCT04072653).In the first stage,cN0 patients underwent axillary LymphPET followed by SLNB.In the second stage,SLNB was omitted in patients with a negative preoperative axillary assessment after integration of LymphPET.Here,we report the results of the first stage.The primary outcome was the NPV of LymphPET to detect macrometastasis of lymph nodes(LN-macro).Results:A total of 189 patients with invasive breast cancer underwent LymphPET followed by surgery with definitive pathological reports.Forty patients had LN-macro,and 16 patients had only lymph node micrometastasis.Of the 131 patients with a negative LymphPET result,16 patients had LN-macro,and the NPV was 87.8%.After combined axillary imaging evaluation with ultrasound and LymphPET,100 patients were found to be both LymphPET and ultrasound negative,9 patients had LN-macro,and the NPV was 91%.Conclusions:LymphPET can be used to screen patients to potentially avoid SLNB,with an NPV>90%.The second stage of the SOAPET trial is ongoing to confirm the safety of omission of SLNB according to preoperational axillary evaluation integrating LymphPET.
文摘Current histopathological staging procedures in colorectal cancer(CRC)depend on midline division of the lymph nodes(LNs)with one section of hematoxylin and eosin staining.Cancer cells outside this transection line may be missed,which could lead to understaging of Union for International Cancer Control Stage II high-risk patients.The one-step nucleic acid amplification(OSNA)assay has emerged as a rapid molecular diagnostic tool for LN metastases detection.It is a molecular technique that can analyze the entire LN tissue using a reversetranscriptase loop-mediated isothermal amplification reaction to detect tumorspecific cytokeratin 19 mRNA.Our findings suggest that the OSNA assay has a high diagnostic accuracy in detecting metastatic LNs in CRC and a high negative predictive value.OSNA is a standardized,observer-independent technique,which may lead to more accurate staging.It has been suggested that in stage II CRC,the upstaging can reach 25%and these patients can access postoperative adjuvant chemotherapy.Moreover,intraoperative OSNA sentinel node evaluation may allow early CRC to be treated with organ-preserving surgery,while in more advanced-stage disease,a tailored lymphadenectomy can be performed considering the presence of aberrant lymphatic drainage and skip metastases.
文摘Aim: To assess the predictive value of the Baveno VI criteria for the diagnosis of large esophageal varices (EV) in Black African patient with compensated hepatitis B related cirrhosis. Methods: We carried out a cross-sectional study from January 2 to July 3 (2016), in Department of Gastroenterology at University Hospitals of Cocody (CHUC) and Yopougon (CHUY). All the black African patients included were more than 15 years old and their liver elasticity score (LES) was carried out at Yopougon University Hospital. Hepatitis B related cirrhosis was defined by LES ≥ 11 kPa (FibroScan? (Echosens, France)) with positive HBs antigen (HBsAg) and anti HBc antibody. All the patients with hepatitis B related cirrhosis performed a gastroscopy at Cocody University Hospital and esophageal varices were ranked according to société fran?aise d’endoscopie digestive (SFED) classification. Data analysis was performed by SPSS model 20.0 statistics software (SPSS Inc., Chicago, IL, United States). Diagnostic performance of LES 150,000/mmm3 (Baveno VI criteria) for the diagnosis of large EV by gastroscopy was studied (area under the ROC curve, specificity (Sp), sensitivity (Se), positive predictive value (PPV) and negative predictive value (NPV). Results: During the study period, 720 patients achieved liver FibroScan? at CHUY. Of these, 60 respondents to our inclusion criteria were prospectively included in our study. Twelve (20%) of these 60 patients met the Baveno VI criteria. EV were present in 40% of cases (n = 24) with 6.7% (n = 4), 15% (n = 9) and 18.3% (n = 11) of grade 1, 2 and 3, respectively. (66.7% (n = 40) without EV or with small EV) and 33.3% (n = 20) with large EV. The Baveno VI criteria had a Se, Sp, PPV and NPV of 100%, 41.6%, 30% and 100% respectively for the diagnosis of large EV. The area under the ROC curve of a platelet count greater than 150,000/mm3, a liver elasticity score of less than 20 kPa and combination of both were respectively 0.763 [0.645 - 0.880;P = 0.272];0.588 [0.436 - 0.739;P = 0.01] and 0.650 [0.513 - 0.787 P = 0.005]. Conclusion: The combination of liver elasticity score 150,000/mm3, allowed the exclusion of large esophageal varices at gastroscopy with a 100 % NPV in Black African patients with compensated hepatitis B related cirrhosis.
基金Beijing Hospitals Authority Clinical Medicine Development of Special Funding(No.XMLX202119)Open Project funded by Key Laboratory of Carcinogenesis and Translational Research,Ministry of Education/Beijing(No.2022 Open Project-6)。
文摘Objective:To explore the candidate indications for function-preserving curative gastrectomy and sentinel lymph node navigation surgery in early gastric cancer(EGC).Methods:The clinicopathological data of 561 patients with EGC who underwent radical gastrectomy for gastric cancer at Peking University Cancer Hospital from November 2010 to November 2020 with postoperative pathological stage pT1 and complete examination data,were collected.Pearson’s Chi-square test was used and binary logistic regression was employed for univariate and multivariate analyses.Combined analysis of multiple risk and protective factors for lymph node metastasis(LNM)of EGC was performed.A negative predictive value(NPV)combination model was built and validated.Results:LNM occurred in 85 of 561 patients with EGC,and the LNM rate was 15.15%.NPV for LNM reached 100%based on three characteristics,including ulcer-free,moderately well differentiation and patient<65years old or tumor located at the proximal 1/3 of the stomach.Regarding lymphatic basin metastasis,multivariate analysis showed that the metastatic proportion of the left gastric artery lymphatic basin was significantly higher in male patients compared with female patients(65.96%vs.38.89%,P<0.05).The proportion of right gastroepiploic artery lymphatic basin metastasis in patients with a maximum tumor diameter>2 cm was significantly greater than that noted in patients with a maximum tumor diameter≤2 cm(60.78%vs.28.13%,P<0.05).Conclusions:Characteristics of lymph node stations/basins metastasis will facilitate precise lymph node resection.The NPV for LNM reaches 100%based on the following two conditions:young and middle-aged EGC patients,well-differentiated tumors,and without ulcers;or well-differentiated tumors,without ulcers,and tumors located in the proximal stomach.These findings can be used as the recommended indications for functionpreserving curative gastrectomy and sentinel lymph node navigation surgery.
文摘The Daqing oilfield is a multilayered heterogeneous oil field where the pressure are different in the same vertical profile causing many troubles to the adjustment well drillings. The approximately-balanced drilling technique has been developed and proved to be efficient and successful in Daqing oilfield. This paper discusses the application of approximately-balanced drilling technique under the condition of multilayered pressure in Daqing oilfield, including the prediction of formation pressure, the pressure discharge technique for the drilling well and the control of the density of drilling fluid.
文摘Objective： This study compared the performance of the immunochromatographic strip （ICS） to the Venereal Disease Research Laboratory （VDRL） test and Treponema pallidum haemagglutination assay （TPHA） at a primary health care setting. Methods： The study group was comprised of 150 females randomly drawn from a population of pregnant women attending their first antenatal visit or follow-up visits at West Maternity Hospital in Eldoret Kenya, but without a previous syphilis test during that pregnancy. On-site VDRL, ICS and TPHA tests were performed and immediate treatment provided where appropriate. The performance of the three tests was compared, Results： The sero-prevalence of syphilis as determined by the VDRL test was 3%. There was no significant difference between the ICS and the VDRL test （P 〉 0.05）. The sensitivity and specificity of the ICS test were 80% and 98.6% respectively, while the negative predictive value （NPV） and positive predictive value （PPV） were both 100%. On the other hand, the sensitivity and specificity of the VDRL test were 66.7% and 99.3%, while the NPV and PPV were 80% and 98.6% respectively. The Treponema pallidum haemagglutination assay was used as a reference test and had sensitivity, specificity, NPV and PPV of 100%. Conclusion： The diagnostic accuracy of the ICS compared favorably with theVDRL gold standard. The use of the ICS in Kenya can improve the diagnosis of syphilis in health facilities both with and without laboratories and allow community health care workers to make a rapid diagnosis of the disease, and consequently make immediate therapeutic decisions.
文摘"3R" principle circular economy emphasizes the technical operation level,while the theoretical viewpoint on value-increasing of circular economy makes deep analysis based on environmental economics. The viewpoint takes for that the evaluation of any circular economic model should consider both the economic value and externalities. If the material units unattached to products in the economic system are circulated with value-increasing as more as possible,more value can be created with lower consumption of resources. The essential principle of circular economy is that the material units within an economic system should go through the multiple production to be circulated with value-increasing,the main purpose of circular economy is that the material units shouldn't attach to waste going out of the system as much as possible in order to reduce pollution emissions,the economic mechanism of circular economy is that the economic value chain should be used to pull the material units of the system to achieve smooth circulation.
文摘Introduction: Helicobacter pylori is a gram-negative bacillus responsible for numerous gastroduodenal pathologies, and this infection is a public health problem. The prevalence of infection with this bacterium remains high in countries with limited resources. Diagnosis relies mainly on numerous invasive and noninvasive methods. The aim of this work was to evaluate the different indirect diagnostic methods using bacterial cultures. Methods: We conducted a cross-sectional and analytical study from January to May 2022 in the gastroenterology departments of Douala General Hospital and Douala Military Hospital. All patients aged 18 years and older who were in the gastroenterology consultation and agreed to participate were included in our study. Sociodemographic, clinical, and paraclinical data were collected. Urease, liquid urea, and culture tests were performed from the specimens obtained by fibroscopy. Serological tests were performed on the blood sample. Results: 101 patients were included, 58 were female and 43 were male, for a sex ratio of 1.3. The mean age was 44.2 ± 16 years. The prevalence of infection was 90.5%, 44.1%, 40.6% and 21.8% for serology, direct microbiological examination, RUT (rapid urea test) and culture, respectively. Comparison of the different tests showed sensitivity and specificity of 67.1% and 64%, respectively, for RUT, 100% and 73.7%, respectively, for direct microbiological examination, and 100% and 14.8%, respectively, for serology. The positive and negative predictive values were 39.5% and 100% for serology, 39% and 85% for RUT, and 55.6% and 100% for direct microbiological examination, respectively. Conclusion: The prevalence of Helicobacter pylori infection depends on the type of test used. Direct examination is more reliable than RUT and serology.
文摘Background: Multiplex virus assays are useful in immunocompromised hosts but still challenging in routine clinical settings in terms of their sensitivity, specificity, reproducibility, and time and cost performances. In recent years, we developed a qualitative multiplex virus PCR assay capable of the simultaneous detection of 13 virus species within 3 h. However, because of the multiple and concomitant nature of this virus assay, it should be validated for qualitative reliability. Materials and Methods: As a preclinical examination, this multiplex PCR was able to detect 1.25 × 10<sup>3</sup> copies/mL of 13 synthesized virus genomes and preserved same virus DNAs by the serial dilution method. Blood samples from 40 patients who underwent hematopoietic stem cell transplantation were then examined by multiplex PCR for 13 virus species, followed by quantitative real-time PCR for all 13 virus species as reference PCR when these patients developed symptoms suggestive of viral infection. Results: In 421 cumulative qualitative-quantitative tests, the multiplex PCR certainly detected 1.0 × 103 copies/mL of 5 viruses (CMV, JCV, BKV, HHV-6, ADV) that were frequently detected and thus reasonably analyzed. The positive and negative predictive values of multiplex PCR were 84.2% - 93.3% and 90.7% - 99.0%, respectively, and sensitivity and specificity were 59.0% - 83.3% and 97.2% - 99.2%, respectively, for these 5 viruses. Conclusion: From these performances, the multiplex PCR assay may be acceptable in a routine clinical laboratory setting.
基金supported by National Natural Science Foundation of China (Grant Nos.11801102,11861017)Beijing Natural Science Foundation (Z180006)the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development of the National Institutes of Health.
文摘We investigated the false-negative,true-negative,false-positive,and true-positive predictive values from a general group testing procedure for a heterogeneous population.We show that its false(true)-negative predictive value of a specimen is larger(smaller),and the false(true)-positive predictive value is smaller(larger)than that from individual testing procedure,where the former is in aversion.Then we propose a nested group testing procedure,and show that it can keep the sterling characteristics and also improve the false-negative predictive values for a specimen,not larger than that from individual testing.These characteristics are studied from both theoretical and numerical points of view.The nested group testing procedure is better than individual testing on both false-positive and false-negative predictive values,while retains the efficiency as a basic characteristic of a group testing procedure.Applications to Dorfman’s,Halving and Sterrett procedures are discussed.Results from extensive simulation studies and an application to malaria infection in microscopy-negative Malawian women exemplify the findings.
