AIM: To evaluate the efficacy of a new hepatitis C virus (HCV) core antigen assay developed in China. METHODS: After the determination of HCV infection, 49 serial samples were selected from II regular plasma donor...AIM: To evaluate the efficacy of a new hepatitis C virus (HCV) core antigen assay developed in China. METHODS: After the determination of HCV infection, 49 serial samples were selected from II regular plasma donors in 5 different plasma stations. To compare the performance of HCV core antigen detection and HCV PCR, these samples were genotyped, and each specimen was analyzed by ELISA for the detection of HCV core antigen and by qualitative HCV PCR. RESULTS: Among all of the sequential samples, the original 23 specimens were HCV RNA-negative, and 36 samples were HCV RNA-positive. Twenty-seven samples (75%) were HCV core antigen-positive from these HCV RNA-positive specimens. Conversely, 27 samples (93.2%) were found HCV RNA-positive in HCV core antigen- positive samples. Intervals between HCV RNA and HCV core antigen-positive, as well as between HCV core antigen-positive and HCV antibody-positive were 36.0 and 32.8 d, respectively. CONCLUSION: This HCV core antigen assay, developed in China, is able to detect much of anti-HCV-negative, HCV RNA-positive preseroconversion window period (PWP) plasma donations.展开更多
Fe-Mn-C-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and cost-effectiveness.However,their limited low-temperature toughn...Fe-Mn-C-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and cost-effectiveness.However,their limited low-temperature toughness restricts their large-scale applications in specific scenarios.The influence of trace amounts of rare earth cerium(Ce)on the low-temperature toughness of Fe-18Mn-0.6C-1.8Al alloys was investigated.The addition of Ce effectively alters the inclu-sions in the alloy,transforming large-sized irregular inclusions into fine ellipsoidal rare earth inclusions.This leads to a significant reduction in both the proportion and average size of the inclusions,resulting in their effective dispersion throughout the matrix and improved cryogenic performance.The presence of Ce-containing inclusions within the matrix reduces stress concentration,thereby inhibiting microcrack formation and improving impact absorption energy.Specifi-cally,the addition of rare earth Ce alters the fracture behavior of the material at room temperature and low temperature,changing from brittle cleavage fracture to a more ductile failure mode.The impact toughness of the Fe-Mn-C-Al alloy is significantly improved by the addition of 0.0048 wt.%Ce,particularly at-196℃where the impact toughness reaches 103.6 J/cm^(2),representing an impressive improvement of 87.3%.展开更多
Cardiovascular system plays an important role in the medical curriculum.How to enable medical students better learn and grasp this part of knowledge is a task and mission faced by teachers.In recent years,with the dev...Cardiovascular system plays an important role in the medical curriculum.How to enable medical students better learn and grasp this part of knowledge is a task and mission faced by teachers.In recent years,with the development and reform of medical teaching,the application of integrated teaching is more and more popular in domestic medical schools.Shanghai Jiao Tong University School of Medicine has also adopted the integrated teaching.As pathology teachers,we take the integrated teaching of cardiovascular system course as an example to introduce our experience.展开更多
基金Supported by the National Key Technologies R&D Program of China during the 10th Five-Year Plan, No. 2001BA705B06 National High Technology Research and Development Program of China (863 Program), No. 2006AA020907
文摘AIM: To evaluate the efficacy of a new hepatitis C virus (HCV) core antigen assay developed in China. METHODS: After the determination of HCV infection, 49 serial samples were selected from II regular plasma donors in 5 different plasma stations. To compare the performance of HCV core antigen detection and HCV PCR, these samples were genotyped, and each specimen was analyzed by ELISA for the detection of HCV core antigen and by qualitative HCV PCR. RESULTS: Among all of the sequential samples, the original 23 specimens were HCV RNA-negative, and 36 samples were HCV RNA-positive. Twenty-seven samples (75%) were HCV core antigen-positive from these HCV RNA-positive specimens. Conversely, 27 samples (93.2%) were found HCV RNA-positive in HCV core antigen- positive samples. Intervals between HCV RNA and HCV core antigen-positive, as well as between HCV core antigen-positive and HCV antibody-positive were 36.0 and 32.8 d, respectively. CONCLUSION: This HCV core antigen assay, developed in China, is able to detect much of anti-HCV-negative, HCV RNA-positive preseroconversion window period (PWP) plasma donations.
基金This work was supported by the National Natural Science Foundation of China(No.52164032)the Hong Kong Scholars Program(2021-077).
文摘Fe-Mn-C-Al alloys have been recognized as promising materials for certain low-temperature applications due to their exceptional mechanical properties and cost-effectiveness.However,their limited low-temperature toughness restricts their large-scale applications in specific scenarios.The influence of trace amounts of rare earth cerium(Ce)on the low-temperature toughness of Fe-18Mn-0.6C-1.8Al alloys was investigated.The addition of Ce effectively alters the inclu-sions in the alloy,transforming large-sized irregular inclusions into fine ellipsoidal rare earth inclusions.This leads to a significant reduction in both the proportion and average size of the inclusions,resulting in their effective dispersion throughout the matrix and improved cryogenic performance.The presence of Ce-containing inclusions within the matrix reduces stress concentration,thereby inhibiting microcrack formation and improving impact absorption energy.Specifi-cally,the addition of rare earth Ce alters the fracture behavior of the material at room temperature and low temperature,changing from brittle cleavage fracture to a more ductile failure mode.The impact toughness of the Fe-Mn-C-Al alloy is significantly improved by the addition of 0.0048 wt.%Ce,particularly at-196℃where the impact toughness reaches 103.6 J/cm^(2),representing an impressive improvement of 87.3%.
文摘Cardiovascular system plays an important role in the medical curriculum.How to enable medical students better learn and grasp this part of knowledge is a task and mission faced by teachers.In recent years,with the development and reform of medical teaching,the application of integrated teaching is more and more popular in domestic medical schools.Shanghai Jiao Tong University School of Medicine has also adopted the integrated teaching.As pathology teachers,we take the integrated teaching of cardiovascular system course as an example to introduce our experience.