Hepatitis A outbreak originating in a day care center: A community case report

A community outbreak of hepatitis A is described, involving 23 persons in a small town in central Israel. Seventy-four percent of the cases were related to a contact with toddlers in one nursery class in a day care center. There were no overt cases in that class itself. The mode of transmission exemplified in this community underlines the difficulties in identifying a common source of hepatitis A infection, which is necessary for the elimination of a further spread of the disease.     

军营一起腺病毒暴发的流行株分离和血清学分析

目的：针对１９９７年８月３０日～９月上旬某军营暴发的一起流感样疾病,迅速明确疫情和找出病原体及血清学依据。方法：应用主要呼吸道病毒抗原桥联快诊技术和病毒分离以及双份血清学检测技术。结果：３２例患者分泌物中有１１例检出腺病毒（Ａｄｖ）抗原,３０例分泌物标本全部分离出病毒流行株,流行株仅与抗腺病毒共同抗原单抗结合（ＩＦＡ＋＋＋）。３０例患者的双份血清分别与流行株作用,有２８例患者血清抗体出现≥４倍升高。３０例密切接触者血清与流行株作抗体检测,抗体几何平均滴度（ＧＭＴ）高达５１．２。结论：结果证实此次流行病是军营新兵的腺病毒暴发流行,流行株属腺病毒那个亚型,尚需进一步鉴定分析。     

Aggregation of childhood leukemia in geographic areas of Greece)

A total of 872 children aged up to 14 years, who were diagnosed withleukemia in Greece during the decade 1980-89, were allocated by place ofresidence to the 601 administrative districts of the country. Evaluation ofspatial clustering was done using the Potthoff-Whittinghill method, whichvalidly assesses heterogeneity of leukemia risk among districts with variableexpected numbers of cases. There was highly significant evidence for spatialclustering occurring particularly among children living in urban and, to alesser extent, semi-urban areas. The evidence was stronger for childrenyounger than 10 years old, applied also to children in different five-yearage groups, and persisted when cases of acute lymphoblastic leukemia wereanalyzed separately. These findings provide support to the hypothesis thatlocalized environmental exposures could contribute to the etiology ofchildhood leukemia, but they cannot distinguish between exposures of physicalor chemical nature, nor can they exclude socially conditioned patterns ofexposure to infectious agents.     

Geographic Clustering Patterns in Mortality from Biliary Tract Cancer in Japan

We calculated the standardized mortality ratios (SMRs) of biliary tract cancer (BTC) in Japan from 1981 to 1990 and statistically analyzed the results according to 333 Secondary Areas of Medical Care, as well as sex and subsite [gallbladder cancer (GBC) and extrahepatic bile duct cancer (BDC)], in order to examine geographic clustering patterns of BTC. In GBC in both sexes, the Secondary Areas of Medical Care with high SMRs were clustered in the eastern part of Japan. In BDC in both sexes, the Areas with high SMRs were clustered between the northern and eastern parts of Japan. In comparison with GBC, this clustering favored the northern part of Japan. In males, the clustering pattern in mortality from BTC was mainly due to the occurrence of BDC. In females, the clustering pattern in mortality from BTC reflected that of GBC. The clustering of BTC, especially GBC, seems to be related to the distribution of plains, basins, and rivers.     

基于伪F统计量的模糊聚类方法在医疗质量综合评价中的应用

目的探讨一种新的基于伪F统计量的最佳聚类分析方法,该方法不需要预先选择类的数目作为先验值.并有效地应用于医疗质量的综合评价.方法首先,应用FCM模糊聚类法(Fuzzy Clustering Method)进行聚类,然后应用PFS(Pseudo F-statistics)统计量作为一个判别函数来确定最佳类数目.结果将该方法应用于某院2002年度各科室医疗质量综合评价,得到了一种合理的综合评价结果.结论该方法基于没有聚类数据的任何先验知识和组成成分信息的前提下,考虑如何确定数据的分类结构.根据应用的情况,发现该方法是医疗质量综合评价的有力工具.     

基于聚类分析的径向基神经网络用于证候诊断的研究

目的:优化中医证候诊断模型,为中医证候诊断标准的研究提供可行性方法.方法:提出用于中医证候诊断的径向基(Radial Basis Function,RBF)神经网络,利用聚类分析确定RBF神经网络隐层的参数,运用最小二乘确定RBF神经网络输出层的参数.结果:通过模型检验,证候诊断模型判准率比BP网络模型判准率高;证候诊断模型训练速度比BP网络模型快.结论:基于聚类分析的RBF神经网络用于中医证候诊断的研究是可行的和有效的.     

一种用于寻找典型病理图像的聚类分析方法

目的：探讨利用K—medoids聚类分析方法来寻找典型病理图像。方法：对正常、低度和高度鳞状上皮内病变宫颈细胞的51个特征参数进行标准化处理，以消除原始变量数量及量纲影响。运用统计软件R对所有特征参数进行K—medoids聚类分析。结果：对于正常、低度和高度鳞状上皮内病变宫颈细胞的分类正确率分别为91．7％、98．0％和92，0％。作为类中心点的3个病理图片可作为典型病理图片指导临床及教学研究。结论：该方法简单、方便，客观性强，可应用到其他医学领域定量研究。     

多变量统计方法在中药资源生态学研究中的应用

文章介绍了多变量统计方法在中药资源生态学研究中的应用,指出多变量统计方法在中药生态环境因子分析、中药材产地适宜性分析方面的重要意义,列举了几种常见的多变量统计方法及其在中药资源生态学中的应用。     

基于专家问卷调查“思伤脾”状态中医证候特征

目的:探讨"思伤脾"状态中医证候分布特征和辨证规律。方法:应用临床流行病学方法,在全国79家三级中医医院及综合性医院中医科同步进行专家问卷调查,运用系统聚类与因子分析相结合的方法挖掘调查表信息中隐含的客观规律。结果:"思伤脾"状态中医辨证可大致分为脾气虚弱、心脾两虚和肝胃不和3个单证,因子分析提取了每一证型的主要辨证依据。结论:"思伤脾"状态调查表符合中医理论,反映临床实际,为进一步多中心大样本调查研究奠定了基础。