1 Introduction The Cretaceous/Tertiary(Paleogene)extinction event was a mass extinction event occurring at about 65 million years ago between the Mesozoic Cretaceous and Cenozoic Tertiary,which is the one closest to t...1 Introduction The Cretaceous/Tertiary(Paleogene)extinction event was a mass extinction event occurring at about 65 million years ago between the Mesozoic Cretaceous and Cenozoic Tertiary,which is the one closest to today among the five major extinction events in the the geological history period(Renne et al.,2013).At the end of the Cretaceous,the proportion of species declined gradually.展开更多
Nondestructive and noninvasive neutron assays are essential applications of neutron techniques.Neutron resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental compositi...Nondestructive and noninvasive neutron assays are essential applications of neutron techniques.Neutron resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental composition of an object.The back-streaming neutron line(Back-n)is a newly built time-of-flight facility at the China Spallation Neutron Source(CSNS)that provides neutrons in the eV to 300 MeV range.A feasibility study of the NRTA method for nuclide identification was conducted at the CSNS Back-n via two test experiments.The results demonstrate that it is feasible to identify different elements and isotopes in samples using the NRTA method at Back-n.This study reveals its potential future applications.展开更多
文摘目的 对石家庄市地区嗜麦芽窄食单胞菌感染患者的背景、临床特征、药敏及炎症等指标进行分析,为临床治疗以及预防嗜麦芽窄食单胞菌感染提供帮助。方法 回顾性分析2021年1月—2023年12月河北省石家庄市人民医院住院病房嗜麦芽窄食单胞菌感染患者基本特征、炎症指标及耐药性变化,对嗜麦芽窄食单胞菌检出情况、抗菌药物年度和季度耐药率的变化、呼吸道源感染和血流感染的耐药率以及临床实验室检测指标进行统计分析。结果 3年期间嗜麦芽窄食单胞菌住院感染患者共计316例,该菌在病原菌检出年度排名中呈上升趋势(第11位升至第8位),患者以男性为主(225例,71.20%),年龄中位数为69岁,呼吸道感染最常见(274例,86.71%),重症监护室与呼吸科感染率最高(均占18.35%)。菌株对米诺环素、左氧氟沙星和复方新诺明的耐药率分别为0.63%(2/316)、9.81%(31/316)和16.46%(52/316),年度及季度间耐药率差异均无统计学意义(均P>0.05)。感染患者的住院时间中位数显著长于匹配对照组[28.00(24.00) d vs. 18.00(16.00) d,P<0.001],住院至感染嗜麦芽窄食单胞菌时间与合并感染病原体种类数呈正相关(r=0.420,P<0.001)。多因素Logistic回归显示,中性粒细胞计数的比值比(odds ratio,OR)(OR=1.141)和血清淀粉样蛋白A(OR=1.003)是感染的独立危险因素,而白蛋白(OR=0.872)是保护因素(均P<0.05)。ROC曲线分析显示,血清淀粉样蛋白A对感染监测的敏感度为81.3%,特异度为58.1%(AUC=0.720)。结论 嗜麦芽窄食单胞菌是石家庄地区住院感染重要病原体之一,患病率呈上升趋势,感染主要以老年男性呼吸道为主,嗜麦芽窄食单胞菌对米诺环素、左氧氟沙星和复方新诺明的年、季度耐药率差异无统计学变化,对米诺环素最敏感。合并感染其他病原微生物种类的数量越多,住院到感染嗜麦芽窄食单胞菌时间越长,合并混合感染,会显著延长患者住院时间。中性粒细胞、C反应蛋白、血清淀粉样蛋白A和白蛋白可用于监测嗜麦芽窄食单胞菌感染程度,临床需加强抗菌药物的合理应用。
基金granted by the National Natural Science Foundation of China(Grant No.41272030)the IGCP608the National Basic Research Program of China(Grant No.2012CB822001).
文摘1 Introduction The Cretaceous/Tertiary(Paleogene)extinction event was a mass extinction event occurring at about 65 million years ago between the Mesozoic Cretaceous and Cenozoic Tertiary,which is the one closest to today among the five major extinction events in the the geological history period(Renne et al.,2013).At the end of the Cretaceous,the proportion of species declined gradually.
基金This work was supported by the National Natural Science Foundation of China(No.12035017)Youth Innovation Promotion Association CAS(No.2023014)Guangdong Basic and Applied Basic Research Foundation(Nos.2020A1515010360 and 2022B1515120032).
文摘Nondestructive and noninvasive neutron assays are essential applications of neutron techniques.Neutron resonance transmission analysis(NRTA)is a powerful nondestructive method for investigating the elemental composition of an object.The back-streaming neutron line(Back-n)is a newly built time-of-flight facility at the China Spallation Neutron Source(CSNS)that provides neutrons in the eV to 300 MeV range.A feasibility study of the NRTA method for nuclide identification was conducted at the CSNS Back-n via two test experiments.The results demonstrate that it is feasible to identify different elements and isotopes in samples using the NRTA method at Back-n.This study reveals its potential future applications.
