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Neural Regeneration Research 2012年第7期7卷 540-545页

作者： xianghua fang Liming Li Xinqing Zhang Hongjun Liu Hongmei Zhang Xiaoming Qin Department of Epidemiology ＆ Biostatistics School of Public Health Peking University Health Sciences Center Beijing 100191 China Department of Evidence-based Medicine Xuanwu Hospital Capital Medical University Beijing 100053 China Department of Neurology Xuanwu Hospital Capital Medical University Beijing 100053 China Department of Geriatrics Xuanwu Hospital Capital Medical University Beijing 100053 China

A total of 710 patients with first-ever ischemic stroke were consecutively recruited between January 2003 and December 2004 from five community hospitals/stations in five districts of Beijing, China. As of December 31, 2008, a total of 2 477 person-years were followed-up. During the five-year follow-ups, 117 adverse events occurred, including all-cause death and acute cardiovascular events （recurrent stroke, acute myocardial infarction, and sudden death）. The five-year cumulative mortality rate was 2.18/100 person-years （54 cases）, with 3.88/100 person-years （96 cases） of acute cardiovascular events and 3.02/100 person-years （75 cases） of recurrent stroke. Multiple factor analyses using the Cox proportional hazards ratio models showed that age, diabetes, and dependence of activities of daily living were independent predictors for death, acute cardiovascular disease events, or recurrent stroke. The results demonstrated that recurrent stroke was a major vascular disease that affected the prognosis of mild or moderate stroke patients. Secondary prevention of stroke patients should include active management of vascular risk factors and rehabilitation.

关键词： ischemic stroke follow-up study predictors prognosis recurrent stroke survival

Relationship between R219K polymorphism of adenosine triphosphate-binding cassette transporter 1 gene and cerebral infarction: A case-controlled analysis

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Neural Regeneration Research 2009年第5期4卷 396-400页

作者： Lifang Zhang Biao Chen Yanhui Du Fanyuan Kong xianghua fang Xiuli Feng VIP Room Affiliated Hospital of Ningxia Medical University Yinchuan 750004 Ningxia Hui Autonomous Region China Department of Neurology Beijing Xuanwu Hospital Beijing 100069 China Laboratory of Neurology Chinese National Human Genome Center Beijing 100176 China

BACKGROUND： Studies have shown that adenosine triphosphate-binding cassette transporter 1 （ABCA1） gene influences atherosclerosis. Studies have also demonstrated that cerebral infarction does not occur often in pre-menopausal women. It has been, therefore, assumed that sex plays a role in R219K polymorphism of ABCA1 gene and cerebral infarction. OBJECTIVE： To explore the relationship between lipid metabolism-correlated R219K polymorphism of ABCA1 gene, risk factors of cerebral infarction and lipid level, and to determine whether there were significant differences in gender between R219K polymorphism of ABCA1 gene and cerebral infarction. DESIGN, TIME AND SETTING： A multicentral and non-randomized, controlled study based on gene polymorphism was performed at the Chinese National Human Genome Center, and lipid concentrations were measured at Beijing Xuanwu Hospital. Patients with cerebral infarction and healthy subjects were enrolled from eight hospitals of six provinces of China between October 2002 and December 2004. PARTICIPANTS： There were 177 patients in the cerebral infarction group, including 119 males and 58 females, with a mean age of （60 -＋ 13） years, and 234 healthy subjects in the normal control group, including 79 males and 155 females, with a mean age of （58 ± 12） years. METHODS： R219K polymorphism of the ABCA1 gene was detected using polymerase chain reaction-restriction fragment length polymorphism, and blood lipid concentrations were simultaneously measured. MAIN OUTCOME MEASURES： Genotype and allele frequency of R219K polymorphic site, and blood lipid concentrations. RESULTS： RR genotype and R allele frequency of males in the cerebral infarction were significantly greater than males in the normal control group [RR genotype： x2 = 5.305, OR （95% CO, 2.326 （1.120 4.828）, P〈 0.05; R allele： x2= 4.219, OR （95% CO, 1.528 （1.019 2.292）, P〈 0.05]. In addition, RR genotype and R allele frequency of males were significantly greater than females in the cerebral infarction group [RR genotype： x2= 5.172, OR （9

关键词： ABCA1 gene R219K polymorphism lipid cerebral infarction

Software Defect Prediction Using Fuzzy Integral Fusion Based on GA-FM

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Wuhan University Journal of Natural Sciences 2014年第5期19卷 405-408页

作者： LI Kewen CHEN Chenxi LIU Wenying fang xianghua LU Qinghua College of Computer and Communication Engineering China University of Petroleum

The fuzzy measure and fuzzy integral are applied to the classification of software defects in this paper. The fuzzy measure of software attributes and attributes＇ sets are treated by genetic algorithm, and then software attributes are fused by the Choquet fuzzy integral algorithm. Finally, the class labels of soft- ware modules can be output. Experimental results have shown that there are interactions between characteristic attributes of software modules, and also proved that the fuzzy integral fusing method using Fuzzy Measure based on Genetic Algorithm （GA-FM） can significantly improve the accuracy for software defect prediction.

关键词： defect prediction genetic algorithm fuzzy measure fuzzy integral

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代谢正常肥胖诊断标准及其对患病率的影响

中华流行病学杂志 2020年第2期41卷 284-289页

作者：刘春晓方向华首都医科大学宣武医院循证医学中心北京100053

肥胖问题日趋严重,然而近来研究发现并非所有肥胖均对健康有害,并提出代谢正常肥胖亚型的概念。目前代谢正常肥胖尚无统一定义及诊断标准。通过梳理国内外代谢正常肥胖相关文献,对其不同诊断标准进行综述,归纳其差异所在并分析不同诊断... 详细信息

肥胖问题日趋严重,然而近来研究发现并非所有肥胖均对健康有害,并提出代谢正常肥胖亚型的概念。目前代谢正常肥胖尚无统一定义及诊断标准。通过梳理国内外代谢正常肥胖相关文献,对其不同诊断标准进行综述,归纳其差异所在并分析不同诊断标准对其患病率差异造成的影响,旨在为我国肥胖防治的精准预防提供参考依据。

关键词：肥胖代谢综合征胰岛素抵抗

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多学科联合开展临床循证医学教学的优势

中华流行病学杂志 2016年第1期37卷 128-129页

作者：方向华王淳秀首都医科大学宣武医院循证医学中心北京100053

本文介绍了在医学本科生、研究生和医学继续教育中开展临床循证医学教学的实践经历和体会。教研室由多学科人员组成，包括流行病学、内（外）科医生、图书馆专家等构成，通过多次的集体备课，教案讨论、试讲，使循证医学的教学日趋成熟... 详细信息

本文介绍了在医学本科生、研究生和医学继续教育中开展临床循证医学教学的实践经历和体会。教研室由多学科人员组成，包括流行病学、内（外）科医生、图书馆专家等构成，通过多次的集体备课，教案讨论、试讲，使循证医学的教学日趋成熟。强有力的组织领导、对于教学理念的求新求精、努力学习与知识更新、团结协作是立足的根本。

关键词：循证医学教学实践多学科

老年人慢性肾脏病诊断标准和分期以及流行病学研究现状

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中华老年医学杂志 2016年第5期35卷 556-559页

作者：顾乡方向华北京市老年病医疗研究中心首都医科大学宣武医院循证医学中心 100053

鉴于慢性肾脏病（chronic kidney disease，CKD）及其引起的终末期肾病（end stage renal disease，ESRD）对于人类生命和健康的威胁及所造成的巨额卫生资源消耗，关于CKD的研究日益受到重视。由于老年人的特殊性，目前CKD的定义及分期... 详细信息

鉴于慢性肾脏病（chronic kidney disease，CKD）及其引起的终末期肾病（end stage renal disease，ESRD）对于人类生命和健康的威胁及所造成的巨额卫生资源消耗，关于CKD的研究日益受到重视。由于老年人的特殊性，目前CKD的定义及分期、肾功能评估的公式是否应该有别于中青年人一直备受争议，本文对上述问题进行了全面的综述。同时对目前世界各国老年人群的CKD患病调查现况及患病的人群特点、流行趋势进行了归纳总结，并就导致CKD患病率在各个人群、各个调查之间存在差异的可能原因进行分析。

关键词：肾病诊断

An Electro-Mechanical Coupled Mesh-Free Method for Fracture Analysis of Cracks in Piezoelectric Ceramic Materials

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An Electro-Mechanical Coupled Mesh-Free Method for Fracture ...

Zn_(3)(VO_(4))_(2):xDy^(3+)黄色荧光粉的制备与性能

The Sixth World Congress on Computational Mechanics in Conjunction with the Second Asian-Pacific Congress on Computational Mechanics

作者： xianghua Guo, Daining fang Department of Engineering Mechanics, Tsinghua University, Beijing, 100084, China

Based on the moving least square interpolation, an electro-mechanical coupled element free Galerkin method is developed to analyze crack propagation in piezoelectric ceramic structures subjected to electro-mechanical coupled loading. The EFG method establishes discrete equations in term of the Gauss integration based on background, so it is accurate and stable. In this paper, the displacement and electric potential are employed as nodal variables and the general displacement boundary conditions are introduced into discrete equations by the penalty function method, so that the stiff matrix is sparse, symmetrical and positive definite, which can considerably reduce computational effort. In order to satisfy the discontinuity of both mechanical and electric displacements in nonconvex bodies, such as cracks and holes, the discontinuous diffraction functions [1] are introduced into weight functions. An infinite plate with a central circular defect is studied to verify the validity of our electro-mechanical coupled method. The agreement between the predicted stress and electric field distribution with those obtained from existing numerical simulation [2] and exact theoretical solutions [3]. In order to investigate both stress and electric field distributions at a crack tip in a piezoelectric material, a single edge-notched specimen has been modeled. In the discrete equations, some basis functions with singular items are adopted to catch the singularity of stress and electric field. In addition, the nodal refinement is carried out around the crack tip. The numerical results show that both the ratio of the electrical to the mechanical loads and the direction of electric field have important effects on the angle at which the hoop stress reaches its maximum value, which makes the crack has the tendency to propagate straightward or deviate away from the crack line. In some practical performances, the piezoelectric materials are often deposited on the substrates. Some cracks will be found in the interface of piezoelectric mat

关键词：

来源： cnki会议评论

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材料导报 2024年第S1期38卷 33-37页

作者：张辉霞吴同华孙芳贾相华牡丹江师范学院超硬材料重点实验室黑龙江牡丹江157011

以氧化锌和五氧化二钒为原料,氧化镝为掺杂离子,利用高温固相法合成了一系列的掺杂稀土镝的钒酸锌黄色荧光粉。对其光学性能进行了研究,结果表明,所制备的粉体都保持了矾酸锌的结构,并且荧光粉的发射光是VO_(4)^(3+)基团和Dy所致。当激... 详细信息

以氧化锌和五氧化二钒为原料,氧化镝为掺杂离子,利用高温固相法合成了一系列的掺杂稀土镝的钒酸锌黄色荧光粉。对其光学性能进行了研究,结果表明,所制备的粉体都保持了矾酸锌的结构,并且荧光粉的发射光是VO_(4)^(3+)基团和Dy所致。当激发波长为350 nm时,其发射峰是位于510~595 nm的宽带状光谱,主峰位于563 nm处。研究了合成温度和Dy掺杂浓度对发光性能的影响,结果表明,当合成温度为800℃和Dy掺杂摩尔分数为6%时,Dy^(3+)能很好地进入到矾酸锌的晶格中,减小了荧光材料光学带隙,增强了光的吸收性能。暗室环境下封装后的荧光粉LED芯片具有良好的黄色发光性能。

关键词：氧化镝光学带隙发光性能黄色荧光粉钒酸锌

植被类型与管理方式对4种森林树种土壤活性碳氮及碳通量的影响

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智慧农业导刊 2022年第15期2卷 13-17页

作者：方向华胡伟尤根彪刘玲娟丽水职业技术学院浙江丽水323000 丽水市莲都区生态林业发展中心浙江丽水323000 丽水市白云山生态林场浙江丽水323000 钱江源-百山祖国家公园龙泉保护中心浙江丽水323000

对土壤活性碳氮含量与CO_(2),CH4通量的研究,对研究森林土壤养分状况和碳氮循环有重要意义。以浙江凤阳山4种树种——马尾松(inus massoniana Lamb)、木荷(Schima superba)、青冈(Cyclobalanopsis glauca)、甜槠(Castanopsis eyrei)林0~20 cm的表层土壤为研究对象,比较植被类型和管理方式对土壤溶解性碳氮养分、微生物量碳氮和CO_(2),CH4通量的影响。结果表明(1)植被类型和树龄对土壤碳氮比和含水率有重要影响;(2)土壤中无机氮含量的变化趋势与pH值一致,与树龄相反;(3)微生物生物量与氮的比值受土壤碳氮比和含水率的显著影响;(4)施硝态氮肥、长期连作等人工管理方式都会导致CH4通量增加。通过调整土壤水分条件和pH值,改进管理方法,有利于降低森林温室气体排放。

关键词：植被类型土壤溶解性有机碳土壤无机氮微生物量碳氮碳通量

序列位置效应联合延迟回忆识别不同认知障碍水平患者的研究

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中华老年医学杂志 2021年第2期40卷 158-162页

作者：黄娟李放方向华王淳秀关绍晨首都医科大学附属复兴医院神经内科北京100038 首都医科大学附属宣武医院循证医学中心北京100053

目的探索序列位置效应联合延迟回忆在区分不同认知障碍水平人群的诊断价值。方法共纳入310例受试,其中认知正常(NC)组128例,轻度认知功能障碍(MCI)组133例,轻度阿尔茨海默病(AD)组49例。3组性别、年龄、受教育程度无显著性差异。所有受... 详细信息

目的探索序列位置效应联合延迟回忆在区分不同认知障碍水平人群的诊断价值。方法共纳入310例受试,其中认知正常(NC)组128例,轻度认知功能障碍(MCI)组133例,轻度阿尔茨海默病(AD)组49例。3组性别、年龄、受教育程度无显著性差异。所有受试进行成套神经心理学测验,使用听觉词语学习测验量表华山版(AVLT-H)进行序列位置效应的研究。结果AVLT-H即刻回忆第2次、第3次以及短延迟、长延迟的首因效应在3组间得分差异有统计学意义(P0.05)。长延迟回忆首因效应+短延迟回忆作为联合指标可比其他记忆指标更好区分不同水平认知人群,其敏感度、特异度分别为83.21%、71.43%(NC比MCI);85.71%、92.86%(NC比轻度AD);66.67%、75.57%(MCI比轻度AD)。结论长延迟回忆的首因效应联合短延迟回忆可辅助区分不同认知障碍水平患者。

关键词：序列位置效应延迟回忆认知障碍