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31.
为解析拟穴青蟹(Scylla paramamosain)血卵涡鞭虫病的流行病学特征,于2012年4—11月采用跟踪监测和实地调查的方法,结合病原分离鉴定及病蟹的病理学观察,统计分析了浙江省温州地区养殖拟穴青蟹血卵涡鞭虫病的流行情况。结果表明,患病拟穴青蟹的肝胰腺、肌肉、鳃等组织病理显示有大量血卵涡鞭虫侵染,并能用PCR方法快速检出。温州地区养殖拟穴青蟹血卵涡鞭虫病在每年5—11月均有发生,7—9月为集中发病时间,死亡高峰出现于8—9月之间,年份间(2010—2012)与发病率无相关性,而不同月份对病害的发生有极显著影响(P0.01)。不同发育阶段以脱壳期的发病率相对较高,发病蟹的规格主要以50g以下的幼蟹和250g以上的成蟹为主。拟穴青蟹血卵涡鞭虫病的发生与水温(r=0.756)和盐度(r=0.631)变化关系较密切,夏、秋季节受梅雨、台风影响而引起水温和盐度的剧烈变化可能是暴发血卵涡鞭虫病的诱发因素。 相似文献
32.
对流行病学分析显示大珠母贝幼虫群体的死亡是以暴发性方式发生,从胚胎发育前期至变态期,幼虫存在两个死亡高峰,分别位于壳顶期之前或壳顶期和壳顶后期.大珠母贝幼虫群体的死亡率与RLO感染之间存在显著的相关性,在RLO感染的高峰之后均相应伴随幼虫群体死亡率的高峰,随着RLO感染率和感染强度的降低,幼虫群体死亡率也明显降低.在TEM下未发现未受精卵母细胞、受精卵和胚胎早期幼虫感染RLO,最先出现RLO包涵体阳性感染的时期为24h尚未摄食的D形期幼虫,故认为RLO可能不是通过垂直传播,而是通过外界接触感染的方式感染宿主,贝体感染至发病死亡存在潜伏期. 相似文献
33.
34.
The onset and sPread of diseases in dricultured Anrnals are resulted frOm the mutule ef-fect of pathogen, hOSt and environrnnt. Epidemology takes the diseased AnInal poPulationsas the study object, rnakes observation and exPeriment on the field as the primp method ofstUdy and stuha the mutule effec Of PathOgen, hOS and environrnen by inVeSigating the na-ttire distribution of diseases and ePidendc mechedsm. To date, succeSSful exarnple of epidend-obo study on lerne shellfish deseases is… 相似文献
35.
The death which occurred in juvenile population was a severe problem in the course ofPinctada maxima artificial culture. With the methods of field investigation, histological study and statistic analyses, the epidemiological study was carried out on the disease and death in juvenile populations of Pinctada maxima in the Xinying Pearl Oyster Mariculture Farm of Lingao County (for the A, B and C batches of cultured juveniles hanged in the sea) and the Xincun Pearl Oyster Mariculture Farm of Lingshui County (for the D batch of cultured juvenile hanged in the pond), Hainan Province from November 1993 to April 1995.The results show that the deaths which occurred in juvenile populations of Pinctada maxima presented an outbreak pattern. The peak of mortality rates, in general, occurred in 4-to 6-month old pearl oyster juveniles, and the mortality rates gradully declined with the extention of pearl oyster age after cul-turing 8 months. The correlation between the mortality rates of juvenile populations and mean 相似文献
36.
37.
Nancy Krieger 《GeoJournal》2009,74(2):87-97
To put on the map: according to the Oxford English Dictionary, whatever is so placed occupies “an important or prominent position” and is “of
some account or importance.” In this brief commentary, I take the opportunity to reflect on several articles by medical/health
geographers and others regarding our Public Health Disparities Geocoding Project and my research, as a social epidemiologist, on the myriad ways racism can harm health. In both cases, my work on these topics
has been motivated by my desire, starting a quarter of a century ago, to put health inequities on the map: as a topic of public
concern, research, and action. The insightful and informative points and questions raised by the geography-oriented articles
underscore the importance of bringing the best of our respective disciplinary insights and expertise to illuminate the profound
connections between social justice and public health, between our bodily truths and the body politic, so as to further the
goal of embodying equity––in an ecologically sustainable world. 相似文献
38.
Social epidemiology as medical geography: Back to the future 总被引：1，自引：1，他引：0
Tom Koch 《GeoJournal》2009,74(2):99-106
There is something very traditional about Nancy Krieger’s decidedly modern work. She advances a social epidemiology that is
multidisciplinary, advancing a “quantitative population science” that is also spatial in its approach and method of analysis.
Many geographers see their work as affirming the potential of medical cartography and geography as disciplines critical to
public health studies of disease incidence. This article argues that the history of epidemiology and public health are historically
spatial and geographic, a link lost in the research of many twentieth century health researchers. A review of the history
of medical geography, and of public health, insists upon the spatiality of disease studies as a critical groundwork not simply
for contemporary disease studies but for the history of disease studies as they have slowly developed over for more than 200 years. 相似文献
39.
The objective of this study is to quantify and model spatial dependence in mosquito vector populations and develop predictions
for unsampled locations using geostatistics. Mosquito control program trap sites are often located too far apart to detect
spatial dependence but the results show that integration of spatial data over time for Cx. pipiens-restuans and according to meteorological conditions for Ae. vexans enables spatial analysis of sparse sample data. This study shows that mosquito abundance is spatially correlated and that
spatial dependence differs between Cx. pipiens-restuans and Ae. vexans mosquitoes.
相似文献
40.
SARS空间传播模式及其在疫情监控信息系统设计中的应用 总被引：4，自引：0，他引：4
在中国控制SARS(Severe Acute Respiratory Syndrome)疫情扩散与蔓延的大量科学实践活动基础上，从人地系统科学的理论和观点出发，提出了各种致病因子在人地互动过程中转移路径的逻辑模型，进而又提出了控制SARS疫情发展的人地互动逻辑模型。从后一个模型出发，把中国SARS疫情的发展规律归纳为5种传播模式，即异类病毒转移传播模式、家庭和社区接触传播模式、医院和门诊感染传播模式、市内随机扩散传播模式和飞点跳跃跨区传播模式。其中，跨区传播模式的影响最广泛、危害最巨大、控制起来最艰巨、复杂，是建立中国突发公共卫生事件应急机制、增强应急能力需要解决的主要问题和关键内容。为此，作者对中国的疫情控制应急机制及其实现提出了一些具体的看法和建议，包括对现有疫情系统进行技术改造和创新的建议，在全新运作机制和高技术基础上建立应急疫情监测控制信息系统的概念结构等内容。 相似文献