运动性猝死研究综述

应用文献资料法,对运动性猝死的流行病学和病因学特征进行了探讨和分析。运动性猝死发生率虽低,但发展迅速,其发生与运动项目、运动强度之间没有明显关系,多发在30-60岁,男性多于女性。运动性猝死大多为心源性猝死和脑性猝死,其中冠状动脉粥样硬化是运动性猝死的主要原因。对运动性猝死发生的可能机制进行了探讨并提出了预防措施。     

具有种群动力学和非线性接触率的SIRS流行病模型

建立易感染类中具有 L ogistic种群增长和非线性接触率的 SIRS流行病模型 ;分析该模型的正不变集和平衡位置的存在性 ,研究了疾病消除平衡位置和地方病平衡位置的稳定性 ,最后给出一些数值模拟结果     

The outbreak pattern of the SARS cases in Asia

The severe acute respiratory syndrome (SARS) caused tremendous damage to many Asia countries, especially China. The transmission process and outbreak pattern of SARS is still not well understood. This study aims to find a simple model to describe the outbreak pattern of SARS cases by using SARS case data commonly released by governments. The outbreak pattern of cumulative SARS cases is expected to be a logistic type because the infection will be slowed down due to the increasing control effort by people and/or due to depletion of susceptible individuals. The increase rate of SARS cases is expected to decrease with the cumulative SARS cases, as described by the traditional logistical model, which is widely used in population dynamic studies. The instantaneous rate of increases were significantly and negatively correlated with the cumulative SARS cases in mainland of China (including Beijing, Hebei, Tianjin, Shanxi,the Autonomous Region of Inner Mongolia) and Singapore. The basic reproduction number R0 in Asia ranged from 2.0 to 5.6 (except for Taiwan, China). The R0 of Hebei and Tianjin were much higher than that of Singapore, Hongkong, Beijing, Shanxi, Inner Mongolia, indicating SARS virus might have originated differently or new mutations occurred during transmission. We demonstrated that the outbreaks of SARS in many regions of Asia were wall described by the logistic model, and the control measures implemented by governments are effective. The maximum instantaneous rate of increase, basic reproductive number, and maximum cumulative SARS cases were also calculated by using the logistic model.     

Molecular epidemiology and evolution of worldwide enterovirus 71 strains isolated from 1970 to 2004

Human enterovirus 71 （EV71） is one of the major etiological agents of the hand-foot-and-mouth disease （HFMD） that often causes severe neurological complications. Recently, its outbreaks mainly take place in the torrid zone of the Asia-Pacific region. To study the evolution and genetic variability, we collected 532 EV71 strains with almost complete or complete VP1 sequences （891 nt） isolated worldwide from 1970 to 2004. The pairwise homologies and genetic distances were analyzed. Most strains belong to previously identified genotype B and C. However, a unique strain R13223-1ND-01 appears not to fall into current three genotypes （A, B and C）, and probably represents a new genotype D. Some orphan strains were observed in the genotypes B and C, and their significance in the EV71 evolution was discussed. Moreover, there is a significant co-variance of 6 discrete positions on VP1 （amino acid 43, 58, 164, 184, 240 and 249）. This high co-variability is tightly related with the subgenotypes.     

鸭致病性大肠杆菌中耶尔森菌强毒力岛的分子流行病学调查

为了解耶尔森菌强毒力岛(HPI)在鸭致病性大肠杆菌中的流行情况,根据HPI结构基因irp2和fyuA参考序列设计了引物,用PCR方法对从成都等地分离的64株鸭致病性大肠杆菌和28株健康雏鸭泄殖腔拭子分离的大肠杆菌基因进行了扩增和检测,并对5个菌株相关基因进行了克隆和序列分析.结果表明,irp2和fyuA携带率在鸭大肠杆菌病分离株分别为40.6%(26/64)和39.1%(25/64),在健康鸭泄殖腔大肠杆菌分离株分别25.0%(7/28)和21.4%(6/28).鸭大肠杆菌病分离株携带fyuA和irp2的阳性率显著高于健康鸭大肠杆菌分离株(P<0.05),HPI毒力岛的携带率与菌株的致病性呈明显的正相关.分析表明相关基因与GenBank中参考序列的同源性高达98%以上.     

海口地区人乳头瘤病毒感染的分子流行病学研究

利用PCR扩增和Southen杂交技术,对海口地区人乳头瘤病毒（HPV）型别进行了调查,结果显示,在所抽取的1045份样本中,有436份检出HPV-DNA,总阳性率为41．72％（436／1045）,其中有337份只检出1种型别感染（单侵染）,65份检出2种型别感染（二重侵染）,34份检出3种或3种以上型别感染（三重或三重以上侵染）,分别占感染样本的77．29％,14．91％和7．80％;在单侵染中,高危型所占比例为74．78％（252／337）,不同型别的检出率从高到低分别是HPV16（22．25％）,HPV58（17．89％）,HPV43（16．74％）,HPV52（16．06）和HPV6（8．94％）．其中HPV16,HPV58和HPV43为高危型,其检出率较高,具有一定的区域性．     

2021年污水流行病学热点回眸

污水流行病学是调查人群消费化学物质/感染病原体和健康状况的一种有力和具有成本效益的工具,当前肆虐全球的新冠疫情推动了污水流行病学的迅速发展.从污水样品的采集、前处理及分析,物质的稳定性,校正因子的计算与不确定性分析,实施案例等方面盘点了2021年污水流行病学的重要研究及应用.     

番茄褪绿病毒及植株对其侵染响应性研究进展

目前全球已知的番茄褪绿病毒(Tomato chlorosis virus,ToCV)分离株系可分成3组,它们在中国境内都有被发现,但仍呈区域性分布.ToCV病害主要通过阻断粉虱传播来防治,更长期有效的防控则基于对植株对ToCV侵染的敏感性和抗性的分子遗传基础的了解,和对病毒具有耐受或者抗性的作物品种的培育.为此,综述了近年来在ToCV基因组方面的研究进展以及不同地区病毒分离株的序列特征,并分析了导致番茄耐病、抗病机理研究滞后的原因.     

社交焦虑障碍及其研究进展

社交焦虑障碍作为一种日常生活中的常见心理疾病,其发病率占总体心理疾病中的20%,严重影响人们正常的生活、工作、学习。本文从流行病学、病因、诊断标准与治疗方面对近年社交焦虑障碍的研究情况进行综述。     

The molecular epidemiology of parasites

Summary The explosion of new techniques, made available by the rapid advance in molecular biology, has provided a battery of novel approaches and technology which can be applied to more practical issues such as the epidemiology of parasites. In this review, we discuss the ways in which this new field of molecular epidemiology has contributed to and corroborated our existing knowledge of parasite epidemiology. Similar epidemiological questions can be asked about many different types of parasites and, using detailed examples such as the African trypanosomes and theLeishmania parasites, we discuss the techniques and the methodologies that have been or could be employed to solve many of these epidemiological problems.