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Establishing and popularizing a standard pathological diagnostic model of endoscopic submucosal dissection specimens in China
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作者 Chun Xu Ling Chen +5 位作者 An-Ning Feng Ling Nie Yao Fu Lin Li Wei Li Qi Sun 《World Journal of Gastrointestinal Endoscopy》 2025年第3期60-67,共8页
BACKGROUND Endoscopic submucosal dissection(ESD)is a standardized therapeutic approach for early carcinoma of the digestive tracts.In this regard,the process of histopathological diagnosis requires standardization.How... BACKGROUND Endoscopic submucosal dissection(ESD)is a standardized therapeutic approach for early carcinoma of the digestive tracts.In this regard,the process of histopathological diagnosis requires standardization.However,the uneven development of healthcare in China,especially in eastern and western China,creates challenges for sharing a standardized diagnostic process.AIM To optimize the process of ESD specimen sampling,embedding and slide production,and to provide complete and accurate pathological reports.METHODS We established a practical process of specimen sampling,created standardized reporting templates,and trained pathologists from neighboring hospitals and those in the western region.A training effectiveness survey was conducted,and the collected data were assessed by the corresponding percentages.RESULTS A total of 111 valid feedback forms have been received,among which 58%of the participants obtained photographs during specimen collection,whereas the percentage increased to 79%after training.Only 58%and 62%of the respondents ensured the mucosal tissue strips were flat and their order remained unchanged;after training,these two proportions increased to 95%and 92%,respectively.Approximately half the participants measured the depth of the submucosal infiltration,which significantly increased to 95%after training.The percentage of pathologists who did not evaluate lymphovascular invasion effectively reduced.Only 22%of the participants had fixed clinic-pathological meetings before training,which increased to 49%after training.The number of participants who had a thorough understanding of endoscopic diagnosis also significantly increased.CONCLUSION There have been significant improvements in the process of specimen collection,section quality,and pathology reporting in trained hospitals.Therefore,our study provides valuable insights for others facing similar challenges. 展开更多
关键词 Endoscopic submucosal dissection specimen specimen processing Pathological diagnosis Gastrointestinal endoscopy Continuing education
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Experimental investigations on combined high and low cycle fatigue:Material-level specimen design and strain response characteristics
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作者 Xin DING Dawei HUANG +5 位作者 Zixu GUO Han YAN Xiaojun YAN Yinzhuoran WANG Feng YIN Xu LUAN 《Chinese Journal of Aeronautics》 2025年第1期380-394,共15页
The paper designs a novel material-level specimen and its dedicated fixture suitable for applying Combined high-and low-Cycle Fatigue(CCF)loads.Unlike full-scale or simulation specimens,the CCF specimen eliminates geo... The paper designs a novel material-level specimen and its dedicated fixture suitable for applying Combined high-and low-Cycle Fatigue(CCF)loads.Unlike full-scale or simulation specimens,the CCF specimen eliminates geometrically induced stress gradients in the test region.Experimental data on CCF life and strain responses of ZSGH4169 alloy are acquired under different CCF loads.The Maximum Strain within Each(MSE)CCF cycle is demonstrated to be independent of the Low-Cycle Fatigue(LCF)loads and High-Cycle Fatigue(HCF)stress amplitudes,but exhibits a correlation with the Cycle Ratio of HCF/LCF(Rf).The growth law of MSE changes from linear to logarithmic as Rfdecreases.Strain amplitudes in the dwell stage,observed unaffected by Rf,are quantified as a function of LCF nominal stresses and HCF stress amplitudes.However,under a defined CCF load,strain amplitudes in the dwell stage remain constant.Strain peaks in the dwell stage in a single CCF cycle decrease in a power function with increasing HCF cycles. 展开更多
关键词 Material-level specimen Low-cycle fatigue High-cycle fatigue Combined high-and low-cycle fatigue Fatigue life Strain response
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Dynamic characteristics of coal specimens with varying static preloading levels under low-frequency disturbance load 被引量:2
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作者 WEN Xiao-ze FENG Guo-rui +5 位作者 GUO Jun YU Lu-yang QIAN Rui-peng ZHANG Jie ZHANG Peng-fei FENG Wen-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2644-2657,共14页
The mechanical properties of residual coal pillars under the influence of upward mining disturbances significantly affect the safety of residual mining activities on working faces.This study conducted low-frequency di... The mechanical properties of residual coal pillars under the influence of upward mining disturbances significantly affect the safety of residual mining activities on working faces.This study conducted low-frequency disturbance dynamic uniaxial compression tests on coal specimens using a self-developed dynamic-static load coupling electro-hydraulic servo system,and studied the strength evolutions,surface deformations,acoustic emission(AE)characteristic parameters,and the failure modes of coal specimens with different static preloading levels were studied.The disturbance damage is positively correlated with the coal specimen static preload level.Specifically,the cumulative AE count rates of the initial accelerated damage stage for the coal specimens with static preloading level of 60%and 70%of the uniaxial compressive strength(UCS)were 2.66 and 3.19 times that of the 50%UCS specimens,respectively.Macroscopically,this behaviour manifested as a decrease in the compressive strength,and the mean strengths of the disturbance-damaged coal specimens with 60%and 70%of UCS static preloading decreased by 8.53%and 9.32%,respectively,compared to those of the specimens under pure static loading.The crack sources,such as the primary fissures,strongly control the dynamic response of the coal specimen.The difference between the dynamic responses of the coal specimens and that of dense rocks is significant. 展开更多
关键词 low-frequency disturbance dynamic response coal specimens static preloading level
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Species’ geographical range, environmental range and traits lead to specimen collection preference of dominant plant species of grasslands in Northern China 被引量:1
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作者 Jingya Zhang Cui Xiao +5 位作者 Xiaoyu Duan Xin Gao Hao Zeng Rong'an Dong Gang Feng Keping Ma 《Plant Diversity》 SCIE CAS CSCD 2024年第3期353-361,共9页
Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection... Many different factors,such as species traits,socio-economic factors,geographical and environmental factors,can lead to specimen collection preference.This study aims to determine whether grassland specimen collection in China is preferred by species traits(i.e.,plant height,flowering and fruiting period),environmental range(i.e.,the temperature and precipitation range)and geographical range(i.e.,distribution range and altitudinal range).Ordinary least squares models and phylogenetic generalized linear mixed models were used to analyze the relationships between specimen number and the explanatory variables.Random Forest models were then used to find the most parsimonious multivariate model.The results showed that interannual variation in specimen number between 1900 and 2020 was considerable.Specimen number of these species in southeast China was notably lower than that in northwest China.Environmental range and geographical range of species had significant positive correlations with specimen number.In addition,there were relatively weak but significant associations between specimen number and species trait(i.e.,plant height and flowering and fruiting period).Random Forest models indicated that distribution range was the most important variable,followed by flowering and fruiting period,and altitudinal range.These findings suggest that future floristic surveys should pay more attention to species with small geographical range,narrow environmental range,short plant height,and short flowering and fruiting period.The correction of specimen collection preference will also make the results of species distribution model,species evolution and other works based on specimen data more accurate. 展开更多
关键词 Biological specimen Collection preference Dominant plant species Environmental range Geographical range Species traits
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Perioperative outcomes of transvaginal specimen extraction laparoscopic total gastrectomy and conventional laparoscopicassisted total gastrectomy 被引量:1
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作者 Zhi-Cao Zhang Wen-Sheng Wang +5 位作者 Jiang-Hong Chen Yuan-Hang Ma Qi-Fa Luo Yun-Bo Li Yang Yang Dan Ma 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第6期1527-1536,共10页
BACKGROUND Natural orifice specimen extraction surgery(NOSES)has emerged as a promising alternative compared to conventional laparoscopic-assisted total gastrectomy(LATG)for treating gastric cancer(GC).However,evidenc... BACKGROUND Natural orifice specimen extraction surgery(NOSES)has emerged as a promising alternative compared to conventional laparoscopic-assisted total gastrectomy(LATG)for treating gastric cancer(GC).However,evidence regarding the efficacy and safety of NOSES for GC surgery is limited.This study aimed to compare the safety and feasibility,in addition to postoperative complications of NOSES and LATG.METHODS Dual circular staplers were used in Roux-en-Y digestive tract reconstruction for transvaginal specimen extraction LATG,and its outcomes were compared with LATG in a cohort of 51 GC patients with tumor size≤5 cm.The study was conducted from May 2018 to September 2020,and patients were categorized into the NOSES group(n=22)and LATG group(n=29).Perioperative parameters were compared and analyzed,including patient and tumor characteristics,postoperative outcomes,and anastomosis-related complications,postoperative hospital stay,the length of abdominal incision,difference in tumor type,postoperative complications,and postoperative survival.RESULTS Postoperative exhaust time,operation duration,mean postoperative hospital stay,length of abdominal incision,number of specific staplers used,and Brief Illness Perception Questionnaire score were significant in both groups(P<0.01).In the NOSES group,the postoperative time to first flatus,mean postoperative hospital stay,and length of abdominal incision were significantly shorter than those in the LATG group.Patients in the NOSES group had faster postoperative recovery,and achieved abdominal minimally invasive incision that met aesthetic requirements.There were no significant differences in gender,age,tumor type,postoperative complications,and postoperative survival between the two groups.CONCLUSION The application of dual circular staplers in Roux-en-Y digestive tract reconstruction combined with NOSES gastrectomy is safe and convenient.This approach offers better short-term outcomes compared to LATG,while long-term survival rates are comparable to those of conventional laparoscopic surgery. 展开更多
关键词 Gastric cancer Circular stapler Natural orifice specimen extraction surgery Laparoscopic-assisted total gastrectomy
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Bird specimen number linked with species trait and climate niche breadth
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作者 Xiaoyu Duan Xiongwei Huang +4 位作者 Jingya Zhang Shuo Lv Gang Song Yanping Wang Gang Feng 《Avian Research》 SCIE CSCD 2024年第1期108-115,共8页
Biological specimens are fundamental for taxonomy and flora/fauna research.More importantly,they also play crucial roles in recording environmental impacts on morphology and behavior,which is vital for biodiversity re... Biological specimens are fundamental for taxonomy and flora/fauna research.More importantly,they also play crucial roles in recording environmental impacts on morphology and behavior,which is vital for biodiversity research and conservation.However,there are few systematic studies on the patterns and drivers of bird specimen number at regional scales.This study is the first attempt to examine the relationships between bird specimen number and species traits as well as climate niche breadth in China,aiming to answer two questions:1)how do species’temperature niche breadth and precipitation niche breadth influence specimen number?2)which trait is most associated with bird specimen number?The associations between bird specimen number and explanatory variables were examined using ordinary least squares,generalized linear models,phylogenetic generalized linear mixed models,and multiple comparisons.The results showed that Muscicapidae was the family with the highest specimen number,and Passeriformes was the order with the highest specimen number.Bird specimen number significantly increased with larger temperature niche breadth and precipitation niche breadth.Specimen number was also positively associated with geographic range size,habitat specificity,hunting vulnerability and clutch size,but negatively associated with body size.These findings suggest that future bird specimen collection should pay more attention to birds with limited ecological niches,large body sizes,and small clutch sizes.This research enhances the use of bird specimen data to study and preserve biodiversity. 展开更多
关键词 Biodiversity conservation Biological specimens Bird traits Scientific collection specimen number Temperature and precipitation
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Direct Pointwise Comparison of FE Predictions to StereoDIC Measurements:Developments and Validation Using Double Edge-Notched Tensile Specimen
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作者 Troy Myers Michael A.Sutton +2 位作者 Hubert Schreier Alistair Tofts Sreehari Rajan Kattil 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第8期1263-1298,共36页
To compare finite element analysis(FEA)predictions and stereovision digital image correlation(StereoDIC)strain measurements at the same spatial positions throughout a region of interest,a field comparison procedure is... To compare finite element analysis(FEA)predictions and stereovision digital image correlation(StereoDIC)strain measurements at the same spatial positions throughout a region of interest,a field comparison procedure is developed.The procedure includes(a)conversion of the finite element data into a triangular mesh,(b)selection of a common coordinate system,(c)determination of the rigid body transformation to place both measurements and FEA data in the same system and(d)interpolation of the FEA nodal information to the same spatial locations as the StereoDIC measurements using barycentric coordinates.For an aluminum Al-6061 double edge notched tensile specimen,FEA results are obtained using both the von Mises isotropic yield criterion and Hill’s quadratic anisotropic yield criterion,with the unknown Hill model parameters determined using full-field specimen strain measurements for the nominally plane stress specimen.Using Hill’s quadratic anisotropic yield criterion,the point-by-point comparison of experimentally based full-field strains and stresses to finite element predictions are shown to be in excellent agreement,confirming the effectiveness of the field comparison process. 展开更多
关键词 StereoDIC spatial co-registration data transformation finite element simulations point-wise comparison of measurements and FEA predictions double edge notch specimen model validation
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Research on rock hand specimen naming method based on deep learning and Inception-v3 model
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作者 LI SiJia SHEN YanJie QIAN Ye 《Global Geology》 2024年第4期196-206,共11页
The naming of rock hand specimens is usually conducted by geological workers based on observed mineral composition,texture characteristics,etc.,combined with their own knowledge reserves.The accuracy of identification... The naming of rock hand specimens is usually conducted by geological workers based on observed mineral composition,texture characteristics,etc.,combined with their own knowledge reserves.The accuracy of identification results is limited by the experience,research interests,and identification level of the identifier,as well as the complexity of the rock composition.To improve the efficiency of rock hand specimen identification,this paper proposes a method for rock image recognition and classification based on deep learning and the Inception-v3 model.It encompasses the preprocessing of collected photographs of typical intrusive rock hand specimens,along with augmenting the sample size through data augmentation methods,culminating in a comprehensive dataset comprising 12501 samples.Experimental results show that the model has good learning ability when there is sufficient data.Through iterative training of the Inception-v3 model on the rock dataset,the accuracy of rock image recognition reaches 92.83%,with a loss of only 0.2156.Currently,several common types of intrusive rocks can be identified:gabbro,granite,diorite,peridotite,granodiorite,diabase,and granite porphyry.Software is developed for open use by geological workers to improve work efficiency. 展开更多
关键词 Inception-v3 Keras deep learning image identification naming of the intrusive rocks specimen
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Wireless Preamplifier for the Specimen Current Mode Detector in a SEM
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作者 Valentin G. Dyukov 《Optics and Photonics Journal》 2024年第2期23-28,共6页
Using a scanning electron microscope (SEM) in the back-scattered electron (BSE) mode the composition of multi-element specimens may be determined based on the strong dependence of emission coefficient η on the averag... Using a scanning electron microscope (SEM) in the back-scattered electron (BSE) mode the composition of multi-element specimens may be determined based on the strong dependence of emission coefficient η on the average atomic number of elements Z. The output video signal of the usual BSE detectors is produced from their sensors, and the larger proportion of high-energy electrons with modified spectrum is added. Since η = is/ip (is and ip currents of specimen and probe), better accuracy must be achieved by direct measurements those currents on the specimen surface. Here, an experimental model of a current detector for a presented specimen is described. The cage is mounted on the carousel of the moving specimen stage. The input of the preamplifier is connected to the specimen holder in the form of a disk, the diameter of which is 12 mm. When the probe along its surface scanned, the input potential begins to pulsate with a negative polarity. The output of this preamplifier is connected to a small light-emitting diode, which creates intensity-modulated radiation in the chamber. Thus created the light video signal will be picked up by the photomultiplier of the E-T detector. The modes of true SE and BSE are set by applying tens bias volts of various polarities to the specimens or the cage itself. 展开更多
关键词 Scanning Electron Microscopy Backscattered Electron Imaging Wireless specimen Current Preamplifier Universal (SE/BSE) Dyukov Detector
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Application Effect of Feedforward Control in Outpatient Blood Specimen Management
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作者 Meiying Lu 《Journal of Clinical and Nursing Research》 2024年第6期177-183,共7页
Objective:To analyze the application effect of feedforward control in outpatient blood specimen management.Methods:1,200 patients who had their venous blood collected in outpatient phlebotomy room of our hospital'... Objective:To analyze the application effect of feedforward control in outpatient blood specimen management.Methods:1,200 patients who had their venous blood collected in outpatient phlebotomy room of our hospital's outpatient clinic from January 2021 to April 2021 were selected as study subjects and divided into 600 cases in the control group and 600 cases in the observation group.The two groups of patients were compared in terms of their satisfaction with the staff,the efficiency of the nurses and the quality of nursing care,turnaround time before specimen analysis,the rejection rate of the blood specimens,and the time of result reporting.Results:After the implementation of feedforward control,patients'satisfaction with staff,nurses work efficiency and quality of care,turnaround time before specimen analysis,specimen rejection rate,and result reporting time in the observation group were significantly higher than those in the control group(P<0.05).Conclusion:The application of feedforward control in the management of outpatient blood specimens has significant effect,which effectively improves patients'satisfaction,enhances the efficiency of nurses and the quality of nursing care,shortens the turnaround time of specimens before analysis and the reporting time of results,and reduces the rejection rate of specimens. 展开更多
关键词 Feedforward control Venous blood specimen Nursing management Application effect
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基于逆作法下两种框架结构柱-板节点试验研究 被引量:1
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作者 王欣 胡圣兴 +2 位作者 杨哲 刘国安 李树明 《建筑结构》 北大核心 2025年第1期114-121,150,共9页
为研究在逆作法施工下框架结构柱-板节点的破坏模式和抗震性能,设计制作了4个节点试件,其中2个为原焊接做法的钢环板节点试件,2个为新型混凝土环梁法节点试件,分别对两种节点进行轴压加载及拟静力加载试验。研究了拟静力加载下两种节点... 为研究在逆作法施工下框架结构柱-板节点的破坏模式和抗震性能,设计制作了4个节点试件,其中2个为原焊接做法的钢环板节点试件,2个为新型混凝土环梁法节点试件,分别对两种节点进行轴压加载及拟静力加载试验。研究了拟静力加载下两种节点试件的滞回曲线、骨架曲线、刚度退化、位移延性和耗能能力等抗震性能指标,选取了试件关键位置的应变片进行了数据分析,并使用现行规范公式对试件进行了冲切承载力计算。试验结果表明:相对于钢环板节点试件,环梁法节点试件的承载能力、开裂荷载和累积能量耗散分别提升了20%、25%和73.1%,环梁法节点试件具有优越的强度和刚度,在传递复杂应力方面效果更有效,协同作用更明显。 展开更多
关键词 逆作法 钢环板节点 环梁法节点 抗震性能 轴压加载 拟静力加载 协同作用
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Application of Hand-Sewn Anastomosis in Totally Laparoscopic Radical Resection of Colorectal Cancer with Transanal Specimen Extraction
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作者 Jingyu Wu Tengqi Wang +2 位作者 Yongjing Tian Haibin Sun Haiping Feng 《Proceedings of Anticancer Research》 2024年第6期94-104,共11页
Objective: To explore the value of hand-sewn anastomosis in totally laparoscopic radical resection of colorectal cancr with transanal specimen extraction. Methods: A retrospective descriptive study was conducted. Clin... Objective: To explore the value of hand-sewn anastomosis in totally laparoscopic radical resection of colorectal cancr with transanal specimen extraction. Methods: A retrospective descriptive study was conducted. Clinical data of 54 patients with colorectal cancer who underwent totally laparoscopic transrectal specimen extraction surgery between January 2019 and December 2023 at the Department of Gastrointestinal Surgery, Bayannur City Hospital, were collected. All patients underwent digestive tract reconstruction using hand-sewn end-to-end colonic or rectal anastomosis. Intraoperative and postoperative general conditions, pathological results, complications, and follow-up data were analyzed. Results: Among the 54 cases, 37 were male, and 17 were female. The cases included 26 sigmoid colon cancers, 27 high rectal cancers, and 1 descending colon cancer. All patients underwent totally laparoscopic radical resection of colorectal cancer with transrectal specimen extraction. The average surgical duration was 187.87 ± 61.36 minutes, with 16 (14-19) minutes required for hand-sewn anastomosis. Intraoperative blood loss was 16 (10-200) mL, with no conversions to open surgery or blood transfusions. Postoperative outcomes included first flatus time of 1 (1-3) day, liquid diet resumption on 2 (2-3) days, postoperative Visual Analog Scale (VAS) pain score of 2 (2-3), and hospital stay duration of 8 (7-9) days. The total hospitalization cost was 41,011 (25,655-148,589) Chinese yuan, with an average cost of 42,558.81 ± 8,599.30 Chinese yuan after excluding three cases with complications. Pathological examination revealed all cases to be adenocarcinomas: 20 well-differentiated, 32 moderately differentiated, and 2 poorly differentiated. All resection margins were negative. An average of 16.85 ± 7.97 lymph nodes were dissected. Pathological staging included 18 stage I, 17 stage II, and 19 stage III cases. Postoperative complications included 2 cases of anastomotic leakage (3.7%), 1 case of anastomotic stricture (1.8%), and 1 case of pulmonary infection (1.8%). No unplanned readmissions or postoperative deaths occurred during the 30-day follow-up period. Conclusion: Hand-sewn anastomosis in totally laparoscopic radical resection of colorectal cancer with transanal specimen extraction is safe and feasible. 展开更多
关键词 Hand-sewn anastomosis Colorectal cancer Natural orifice specimen extraction surgery Totally laparoscopic
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2017-2024年某三甲医院重症医学科鲍曼不动杆菌耐药率变迁 被引量:1
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作者 张丽伟 冯诚怿 +4 位作者 王鹏飞 朱丽丽 金丹 江淑芳 狄佳 《中华医院感染学杂志》 北大核心 2025年第13期2001-2006,共6页
目的对重症医学科(ICU)连续8年鲍曼不动杆菌(AB)检出情况和耐药率进行分析,为临床合理用药和控制感染提供依据。方法回顾分析2017-2024年常州市第一人民医院ICU中AB和耐碳青霉烯类鲍曼不动杆菌(CRAB)检出株数和标本分布,并对耐药率变迁... 目的对重症医学科(ICU)连续8年鲍曼不动杆菌(AB)检出情况和耐药率进行分析,为临床合理用药和控制感染提供依据。方法回顾分析2017-2024年常州市第一人民医院ICU中AB和耐碳青霉烯类鲍曼不动杆菌(CRAB)检出株数和标本分布,并对耐药率变迁进行分析。结果2017-2024年ICU共分离AB 2078株,占比18.03%,各年份之间趋势变化无统计学差异(χ^(2)=-1.573,P=0.116);2017-2024年AB分离株主要来源于痰液(58.08%)和灌洗液(24.25%),8年间痰标本比例逐渐下降(χ^(2)=-8.257,P<0.001),灌洗液标本逐步上升(χ^(2)=12.964,P<0.001);2017-2021年CRAB的检出率分别为91.48%、92.61%、92.56%、82.53%和52.44%,呈逐年下降趋势,2022-2024年又开始呈现上升趋势,差异有统计学意义(χ^(2)=-2.277,P=0.012);其中痰液和灌洗液中CRAB的检出率均呈现下降后又上升的趋势(均P<0.05)。AB对哌拉西林、米诺环素耐药率呈现缓慢上升趋势,对庆大霉素、替加环素等的耐药率呈现下降趋势,差异均有统计学意义(P<0.05);AB对亚胺培南、美罗培南等耐药率一直高于90%,无变化趋势。结论不动杆菌属是医院感染的重要病原菌,近两年CRAB的检出率呈现下降后又反升的趋势。临床应规范痰培养送检,增加无菌标本送检,AB对临床常用抗菌药物呈现较高的耐药性,对于CRAB感染,可以采用多黏菌素B、替加环素和米诺环素等抗菌药物治疗。 展开更多
关键词 重症医学科 鲍曼不动杆菌 耐碳青霉烯类鲍曼不动杆菌 标本分布 耐药率变迁
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超高性能混凝土加固受损钢筋混凝土梁受弯性能试验研究 被引量:1
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作者 寇佳亮 温江 +1 位作者 齐悦 周恒 《地震工程与工程振动》 北大核心 2025年第1期217-228,共12页
为研究超高性能混凝土(ultra-high performance concrete,UHPC)加固受损试件的力学性能,共设计10根UHPC加固受损钢筋混凝土梁,通过四点弯曲性能试验,研究UHPC加固钢筋混凝土(reinforced concrete,RC)梁受弯的裂缝开展情况、破坏形态、... 为研究超高性能混凝土(ultra-high performance concrete,UHPC)加固受损试件的力学性能,共设计10根UHPC加固受损钢筋混凝土梁,通过四点弯曲性能试验,研究UHPC加固钢筋混凝土(reinforced concrete,RC)梁受弯的裂缝开展情况、破坏形态、承载能力和位移,分析了不同加固厚度、不同加固方式对UHPC加固受损RC梁的受弯性能影响。研究结果表明:UHPC加固受损RC梁的承载能力有极大的提升,峰值荷载最高提升194%;发生破坏时的裂缝较原梁数目多且发展较完全;延性较原梁有很大的提升,其中加固梁相较于原梁的位移延性系数增大了49.77%~178.31%;提出了UHPC加固混凝土梁峰值荷载计算方法及基本假定,将试验参数代入公式,结果与试验值较为吻合,表明所提出的计算公式可以有效地预测此类加固梁的峰值荷载。 展开更多
关键词 超高性能混凝土 加固试件 受弯性能 承载能力 本构模型
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综合干预措施在提高住院患者抗菌药物治疗前病原学送检率中的效果评价 被引量:3
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作者 张俏 贾冰 +1 位作者 张晓慧 李文玲 《中国实验诊断学》 2025年第1期61-66,共6页
目的探索提升住院患者抗菌药物治疗前病原学送检率的综合干预措施并评估干预措施的效果。方法选取某三级医院2023年1月至6月的所有住院患者为研究对象,将未采取干预措施的1~3月作为干预前阶段,4~6月作为干预后阶段,比较干预前后住院患... 目的探索提升住院患者抗菌药物治疗前病原学送检率的综合干预措施并评估干预措施的效果。方法选取某三级医院2023年1月至6月的所有住院患者为研究对象,将未采取干预措施的1~3月作为干预前阶段,4~6月作为干预后阶段,比较干预前后住院患者病原学标本送检率、抗菌药物使用率、病原学标本构成、微生物标本阳性率、重点多重耐药菌检出率、医院感染诊断相关病原学送检率等指标之间的差异。结果住院患者抗菌药物治疗应用前病原学送检率、指向特定病原体送检率、非指向特定病原体送检率分别由干预前31.03%、11.03%、26.48%提升至65.82%、23.10%、48.60%,差异有统计学意义(P<0.05);住院患者抗菌药物治疗应用(不分前后)病原学送检率、指向特定病原体送检率、非指向特定病原体送检率分别由干预前64.66%、32.63%、54.99%提升至92.48%、39.24%、87.26%,差异有统计学意义(P<0.05);住院患者抗菌药物使用率、治疗性应用抗菌使用率由分别干预前的54.19%、45.47%降至47.40%、41.41%,差异有统计学意义(P<0.05);干预后送检标本构成发生变化,痰液、尿液标本有所降低,血标本、分泌物标本有所提升,差异有统计学意义(P<0.05);干预后送检标本的阳性检出率、重点多重耐药菌检出率、血标本阳性检出率均由干预前的21.88%、4.56%、7.70%提升至25.88%、6.30%、20.24%,差异有统计学意义(P<0.05);干预后医院感染诊断相关病原学送检率由干预前38.30提升至62.86%,差异有统计学意义(P<0.05);结论成立专项活动领导小组、利用信息化手段、加强培训与督导检查、规范标本质量、精准反馈管理等综合干预措施可提高住院患者抗菌药物治疗前病原学送检率和医院感染相关病原学标本送检率,同时提升病原学标本的质量,为抗菌药物合理使用提供依据。 展开更多
关键词 抗菌药物 病原学标本 送检率 使用率 综合干预
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一头小须鲸幼体的骨骼特征
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作者 李娜 苏天凤 +1 位作者 张楠 艾红 《海洋渔业》 北大核心 2025年第4期564-571,共8页
为详细了解小须鲸[Balaenoptera acutorostrata(Lacépède,1804)]骨骼的形态特征,对已获得的1副小须鲸幼体骨骼标本的相关测量数据进行了统计分析。结果显示,头骨背面呈锐角等腰三角形,左右对称;脊椎模式为C7+T11+L12+Ca23=53... 为详细了解小须鲸[Balaenoptera acutorostrata(Lacépède,1804)]骨骼的形态特征,对已获得的1副小须鲸幼体骨骼标本的相关测量数据进行了统计分析。结果显示,头骨背面呈锐角等腰三角形,左右对称;脊椎模式为C7+T11+L12+Ca23=53;脊椎全长3824mm;颈椎7枚完全分离;胸椎11枚,与11对肋骨相对应,椎体均呈椭圆形;腰椎12枚,椎体比胸椎发达;尾椎23枚,V形骨11枚,位于第1~10尾椎下面,形状大小不一;腕骨5块,具4指,指式为Ⅰ_(5)、Ⅱ_(7)、Ⅳ_(6)、V_(4);肩胛骨呈斧状,扁平;舌骨拱曲两茎舌骨呈棒状;胸骨“十”字形,两侧不对称;肋骨11对。颈椎质量与椎体宽度之间有明显的幂函数关系(R^(2)=0.8871),颈椎质量与椎体长、带棘突高之间均有明显的二次函数关系(R^(2)=0.9048、R^(2)=0.9057);胸椎质量与椎体长、带棘突高、带横突宽之间均有明显的二次函数关系(R^(2)=0.9699、R^(2)=0.9673、R^(2)=0.8443);腰椎质量与椎体长、带横突宽之间均有明显的二次函数关系(R^(2)=0.8421、R^(2)=0.8832);尾椎质量与椎体宽度、椎体高度之间有明显的幂函数关系(R^(2)=0.9952、R^(2)=0.9884),尾椎质量与椎体长之间有明显的二次函数关系(R^(2)=0.9972);V形骨质量与最大高之间有明显的幂函数关系(R^(2)=0.9184)。研究结果可为小须鲸的基础生物学信息提供数据资料。 展开更多
关键词 小须鲸 骨骼 特征 标本 幼体
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不饱和聚酯树脂包覆层的柱状单轴拉伸试验方法研究
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作者 任黎 石拉 +3 位作者 郑亚新 张皓媛 刘瀚文 付小龙 《兵器装备工程学报》 北大核心 2025年第3期25-32,共8页
针对固体推进剂包覆层的片状哑铃形试样在单轴拉伸试验过程中应力集中效应显著和试验结果离散性大的问题,提出了不饱和聚酯树脂包覆层的柱状拉伸试样设计方案。仿真模拟不同过渡半径下的片状试件和柱状试件,发现柱状式样在相同过渡半径... 针对固体推进剂包覆层的片状哑铃形试样在单轴拉伸试验过程中应力集中效应显著和试验结果离散性大的问题,提出了不饱和聚酯树脂包覆层的柱状拉伸试样设计方案。仿真模拟不同过渡半径下的片状试件和柱状试件,发现柱状式样在相同过渡半径下比片状试样更易断裂,特别在45 mm过渡半径下断裂时间最短;柱状试样的应力分布更均匀,集中区域较小。试验结果表明,柱状试样在-40、20、50℃的抗拉强度离散度为0.63%、0.41%和0.46%,伸长率离散度为0.70%、0.34%和0.51%;对比之下,片状试样抗拉强度离散度为2.03%、1.31%和1.26%,伸长率离散度为1.15%、1.05%和1.57%,柱状试样的有效数据离散度小于片状试样,实验数据有效率达92%。研究表明,柱状试样有效降低了应力集中导致的实验结果离散性;试样的最佳工程标距为12 mm,过渡半径为45 mm;柱状单轴拉伸试验方法有助于获得更可靠的测试结果。 展开更多
关键词 片状试样 柱状试样 单轴拉伸 应力集中 包覆层
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微量标本细胞蜡块制作技术在脑脊液病理诊断中的应用
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作者 刘甜 阎红琳 +4 位作者 徐励 饶洁 李婉 成红豆 袁静萍 《临床与实验病理学杂志》 北大核心 2025年第4期543-545,共3页
目的探讨微量标本细胞蜡块的制作技术在脑脊液病理诊断中的应用价值。方法收集武汉大学人民医院临床送检的脑脊液标本30例作为研究对象。其中15例为2023年之前送检标本,采用传统细胞蜡块制作方法,另15例采用微量标本细胞蜡块制备技术制... 目的探讨微量标本细胞蜡块的制作技术在脑脊液病理诊断中的应用价值。方法收集武汉大学人民医院临床送检的脑脊液标本30例作为研究对象。其中15例为2023年之前送检标本,采用传统细胞蜡块制作方法,另15例采用微量标本细胞蜡块制备技术制作细胞蜡块。通过原始制作细胞蜡块方法、微量标本细胞蜡块的制备方法、HE染色及免疫细胞化学染色,对疾病进行明确的病理诊断。结果应用微量标本细胞蜡块的制备方法相比于原始的细胞蜡块制作方法对于脑脊液的检测成功率更高。结论应用微量标本细胞蜡块的制备方法对于脑脊液的诊断有一定的应用价值,值得推广。 展开更多
关键词 微量标本细胞蜡块 脑脊液 病理诊断
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岩矿石标本宽频带电性参数快速测量方法研究
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作者 付国红 雷泽宁 +1 位作者 程辉 刘阳阳 《仪器仪表学报》 北大核心 2025年第2期152-164,共13页
岩矿石标本电性特征的研究是地球物理勘探中一项重要的基础性工作,针对变频法测量岩矿石标本电性参数存在效率低、抗干扰能力较差等问题,提出基于逆重复m序列的岩矿石标本宽频带电性参数测量方法并设计了测量系统。系统采用编码恒流信... 岩矿石标本电性特征的研究是地球物理勘探中一项重要的基础性工作,针对变频法测量岩矿石标本电性参数存在效率低、抗干扰能力较差等问题,提出基于逆重复m序列的岩矿石标本宽频带电性参数测量方法并设计了测量系统。系统采用编码恒流信号激励的方式,利用编码信号源的频点分布特性和多频点数据处理手段,实现发送一组编码矩形波电流便可获得岩矿石标本多个频点响应信息的高效测量。介绍了逆重复m序列的信号特征,给出了多频点阻抗测量算法流程;通过理论与仿真相结合的方式研究了影响Howland压控电流源性能的重要因素;明晰了实验条件下导致高频段阻抗测量误差的主要因素并给出了校准方案;最后,搭建了测量系统并使用本系统与苏黎世MFIA阻抗分析仪进行了阻抗测量对比实验,结果表明:使用5阶信号时,测量效率相对变频法提高2.3倍,通过调整信号编码参数可实现不同频点密度的测量工作;系统测量频率范围覆盖1 mHz~100 kHz,阻容模型阻抗模值测量误差最大约为0.5%,相位误差最大为23 mrad;校准前后结果对比表明了校准方案在高频段测量的有效性。该系统能够实现宽频阻抗谱快速准确测量,为岩矿石标本电性参数测量提供了一种宽频带快速测量方法与技术支持,具有一定的理论研究意义与工程应用价值。 展开更多
关键词 岩矿石标本 宽频带 电性参数 快速测量 逆重复m序列 Howland电流源
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考虑应力比的TRIP双相钢疲劳裂纹扩展试验及有限元模拟 被引量:2
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作者 邹宗园 宋宇 +1 位作者 池艳阳 陈雷 《钢铁》 北大核心 2025年第4期114-124,共11页
疲劳裂纹扩展行为是引起工程结构件失效的最重要原因之一,而应力比是影响疲劳裂纹扩展行为的重要因素。因此,分析应力比对工程结构件的直接影响十分必要。针对以Mn-N代替Ni元素的高性能TRIP(transformation induced plasticity)双相不锈... 疲劳裂纹扩展行为是引起工程结构件失效的最重要原因之一,而应力比是影响疲劳裂纹扩展行为的重要因素。因此,分析应力比对工程结构件的直接影响十分必要。针对以Mn-N代替Ni元素的高性能TRIP(transformation induced plasticity)双相不锈钢,利用INSTRON 8801液压伺服疲劳试验机,开展应力比分别为0.1、0.2、0.3和0.5的疲劳裂纹扩展试验研究。测得不同应力比下的疲劳裂纹扩展门槛值,分析应力比对疲劳裂纹扩展门槛值的影响规律,并建立了疲劳裂纹扩展门槛值预测模型;基于Pairs模型、Elber模型以及改进的Forman模型,分别对不同应力比下的疲劳裂纹扩展速率与应力强度因子关系进行理论建模,求解模型参数,并比较分析3种模型的预测精度、特点以及适用性,探讨应力比对TRIP双相钢疲劳裂纹扩展速率的影响。基于扩展有限元法,对不同应力比的疲劳裂纹扩展行为开展有限元模拟,模拟结果与试验结果吻合良好。模拟结果准确揭示了TRIP双相钢在不同应力比下疲劳裂纹扩展过程中的等效应力分布、塑性变形区及裂纹形状的变化规律。研究结果不仅可以丰富该类高性能TRIP双相钢疲劳裂纹扩展行为的基础试验数据,而且可以揭示应力比对该类试验钢疲劳裂纹扩展行为的影响规律,对进一步开发并应用此类高性能TRIP双相钢具有非常重要的意义。 展开更多
关键词 TRIP双相钢 CT试样 应力比 疲劳裂纹扩展行为 疲劳裂纹扩展试验 疲劳裂纹扩展门槛值 预测模型 扩展有限元法
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