基于聚类分析的2029例冠心病心绞痛中医证候特点

目的采用聚类分析探讨冠心病心绞痛的中医证候特点。方法 2009年2月-2010年6月,选择山东省7家省、市级中医医院2 029例冠心病心绞痛患者,填写临床信息采集表,运用聚类分析研究冠心病心绞痛的中医证候特点。结果症状指标描述分类：第1类以气虚症状为主,第2类以血瘀症状为主,第3类以实热症状为主。聚类结果：第1类为气阴两亏、肾虚血瘀型,第2类为心脾气虚、痰热扰心型,第3类为肝气郁滞、痰瘀互阻型,第4类为心肾阳虚、气虚血瘀型,第5类为气虚血瘀、郁久化热型,第6类为肝气郁滞、气郁化火型。结论气虚、血瘀、痰热是冠心病心绞痛的主要病机。     

Large transmission cluster of acute hepatitis C identified among HIV‐positive men who have sex with men in Bangkok,Thailand

A rapidly emerging and highly concentrated hepatitis C virus (HCV) outbreak has recently been observed among both acute and chronic HIV‐positive men who have sex with men (MSM) in Bangkok, Thailand. NS5B regions of the HCV genome were amplified using nested PCR and sequenced. Phylogenetic inference was constructed by Maximum Likelihood methods and clusters were identified with support and genetic distance thresholds of 85% and of 4.5%. Forty‐eight (25 acute HIV and 23 chronic HIV) MSM with incident HCV infection were included in the analysis. HCV genotype (GT) was 85% GT 1a and 15% GT 3a or 3b. Median age at HCV diagnosis was 34 (interquartile range, 28‐41) years. 83.3% (40/48) had history of syphilis infection and 36% (16/44) reported crystal methamphetamine use. Only 2 (4%) reported ever injecting drugs, both crystal methamphetamine. In the phylogenetic clustering analysis, 83% belonged to one of two clusters: one large (75%) and one small (8%) cluster. All clusters were GT 1a. MSM with acute HIV infection were more likely to be in a cluster (92%) than those with chronic infection (74%). HCV screening should be regularly performed for MSM in ART clinics, and offering direct‐acting antiviral agents to all MSM with HCV infection might contain the HCV epidemic from expanding further.     

新型冠状病毒肺炎防控措施对疫情时空演变的影响

目的 分析新型冠状病毒肺炎(COVID-19)在不同时期的地理空间分布、空间聚集性特征,评价综合防控措施对疫情发展的影响。方法 根据我国各地区采取I级响应措施及复工复产时间将疫情流行分为三个时间段。收集我国内地各省、直辖市COVID-19动态确诊数据,计算每个时间段的周确诊病例数;运用空间自相关法对COVID-19确诊情况进行统计分析。结果 在第一阶段,疫情呈现以湖北为中心的典型空间正相关(Morans’I=0.144,Z=2.517,P=0.016);局部聚集表现为湖北与周边省份的高-高型和与湖北相距较远省份的低-低型分布。自各地区启动I级响应措施以后,疫情在第二阶段呈现随机分布(Morans’I=-0.017,Z=0.597,P=0.251),局部聚集表现为湖北与周边省份的高-低型和与湖北相距较远省份的低-低型分布。自各地区复工复产后,疫情在第三阶段仍呈现随机分布(Morans’I=-0.055,Z=-0.857,P=0.131);局部聚集表现为广东与江西的高-低型及四川地区的低-低型分布。结论 我国采取的综合防控措施有效地控制了全国疫情蔓延,目前疫情总体处于散发流行状态,应防止疫情反弹。     

Patterns of working hour characteristics and risk of sickness absence among shift-working hospital employees: a data-mining cohort study

Objectives:Data mining can complement traditional hypothesis-based approaches in characterizing unhealthy work exposures. We used it to derive a hypothesis-free characterization of working hour patterns in shift work and their associations with sickness absence (SA).Methods:In this prospective cohort study, complete payroll-based work hours and SA dates were extracted from a shift-scheduling register from 2008 to 2019 on 6029 employees from a hospital district in Southwestern Finland. We applied permutation distribution clustering to time series of successive shift lengths, between-shift rest periods, and shift starting times to identify clusters of similar working hour patterns over time. We examined associations of clusters spanning on average 23 months with SA during the following 23 months.Results:We identified eight distinct working hour patterns in shift work: (i) regular morning (M)/evening (E) work, weekends off; (ii) irregular M work; (iii) irregular M/E/night (N) work; (iv) regular M work, weekends off; (v) irregular, interrupted M/E/N work; (vi) variable M work, weekends off; (vii) quickly rotating M/E work, non-standard weeks; and (viii) slowly rotating M/E work, non-standard weeks. The associations of these eight working-hour clusters with risk of future SA varied. The cluster of irregular, interrupted M/E/N work was the strongest predictor of increased SA (days per year) with an incidence rate ratio of 1.77 (95% confidence interval 1.74–1.80) compared to regular M/E work, weekends off.Conclusions:This data-mining suggests that hypothesis-free approaches can contribute to scientific understanding of healthy working hour characteristics and complement traditional hypothesis-driven approaches.     

凉粉草的特征指纹图谱研究

目的 建立凉粉草特征指纹图谱,为凉粉草的质量控制提供依据。方法 采用HPLC法测定,色谱柱为Dikma Diamonsil（2）C₁₈柱（250 mm×4.6 mm,5 μm）;流动相为乙腈-2%甲酸,梯度洗脱;检测波长为320 nm;体积流量为0.8 mL/min;柱温为25 ℃。结果 建立了凉粉草的特征指纹图谱,34批次凉粉草确定10个共有峰。结论 该法准确可靠,重复性好,为凉粉草质量控制提供了依据。     

Evaluation of clustering algorithms for gene expression data using gene ontology annotations

Background  Clustering is a useful exploratory technique for interpreting gene expression data to reveal groups of genes sharing common functional attributes. Biologists frequently face the problem of choosing an appropriate algorithm. We aimed to provide a standalone, easily accessible and biologically oriented criterion for expression data clustering evaluation.

Methods  An external criterion utilizing annotation based similarities between genes is proposed in this work. Gene ontology information is employed as the annotation source. Comparisons among six widely used clustering algorithms over various types of gene expression data sets were carried out based on the criterion proposed.

Results  The rank of these algorithms given by the criterion coincides with our common knowledge. Single-linkage has significantly poorer performance, even worse than the random algorithm. Ward’s method archives the best performance in most cases.

Conclusions  The criterion proposed has a strong ability to distinguish among different clustering algorithms with different distance measurements. It is also demonstrated that analyzing main contributors of the criterion may offer some guidelines in finding local compact clusters. As an addition, we suggest using Ward’s algorithm for gene expression data analysis.

     

我国情报学硕士学位论文研究热点分析

检索CNKI优秀硕士论文数据库中情报学专业的相关文献,利用BICOMB提取关键词,计算高频关键词的词篇矩阵和共现矩阵,利用SPSS进行聚类,并根据聚类结果绘制战略坐标图。指出情报学硕士论文的研究热点,并讨论战略坐标计算中矩阵对角线取值问题。     

基于关联规则和复杂系统熵聚类的颜正华教授治疗血瘀证用药规律研究

目的：基于中医传承辅助系统软件,分析国医大师颜正华教授治疗血瘀证的用药规律。方法：收集颜正华教授治疗血瘀证的病案,采用关联规则apriori算法、复杂系统熵聚类等方法,确定处方中各种药物的适用频次及药物之间的关联规则,分析颜正华教授治疗血瘀证的用药经验。结果：对筛选出的114个处方进行分析,确定处方中药物的使用频次,药物之间的关联规则,挖掘出12个核心组合和6个新处方。结论：颜正华教授治疗血瘀证经验丰富,多用活血化瘀、调经止痛之品。中医传承辅助系统对挖掘名老中医临床经验具有重要的实用价值。     

基于数据挖掘的孟河名医马培之治疗痰饮用药规律研究

该研究在收集孟河名家马培之治疗痰饮病案的基础上,采用关联规则apriori算法、复杂系统熵聚类等无监督数据挖掘方法,确定处方中各种药物的使用频次及药物之间的关联规则,分析孟河医家马培之治疗痰饮的用药经验,共挖掘出“橘红-枇杷叶-陈皮”等治疗痰饮的18个核心组合和“枳壳-橘红-枇杷叶-陈皮”等9首新处方。研究表明,孟河名医马培之治疗痰饮经验丰富,用药平和轻灵,多用温平缓补、利水渗湿之品。