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81.
目的 探讨1998年洪灾对江西省传染病流行的影响及相关的因素。方法 对江西省洪灾前后的传染病疫情及部分灾区流行的疾病个案进行分析。结果 1997~1999年江西省甲、乙类传染病的发病率分别为198.19/10万、224.68/10万及253.22/10万,1993~1997年平均发病率为187.68/10万。1998年与1997年、1993~1997年的平均水平相比,甲、乙类传染病的总发病率分别上升了13.37%和19.71%,其中以霍乱、出血热和钩端螺旋体病上升最为明显;1999年与1997年、1998年相比,分别上升了27.77%和12.70%,其中以霍乱、甲肝上升最为明显。1998年受灾县与非受灾县、全省和全国比,肠道传染病和自然疫源性疾病上升较明显;灾后第二年,除了肠道传染病继续上升外,呼吸道传染病的上升也较明显。结论 1998年洪灾对江西省传染病的流行产生了一定的影响,部分受灾县传染病的发病有不同程度的上升。 相似文献
82.
《Hepatology research》2003,25(4):447-454
We report an atypical presentation of a chronic active Epstein–Barr virus (EBV) infection with multiple nodular coagulation necrosis in the liver, that appeared as hypodense areas on a CT scan. The patient, a 26-year-old man, was hospitalized following over 2 years of intermittent fever, weight loss and liver abnormalities after contracting infectious mononucleosis. We diagnosed his illness as a chronic active EBV infection (CAEBV) because of the high antibody titers against EBV and the histological evidence of organ disease with demonstration of EBV mRNA. A liver biopsy revealed EBV-infected T-cell infiltration with hemophagocytosis and marked hepatocytolytic necrosis. The patient developed multiple coagulation necrosis with well-defined borders surrounding T-cell aggregation in the liver 8 months later. He died of respiratory failure due to interstitial pneumonitis. The analysis of EBV-genome termini demonstrated a clonal proliferation of T-cells harboring EBV, but no T-cell antigen receptor (TCR) gene rearrangement was observed. We speculate that the pathogenesis of this disease was an atypical expression of organ damage as a result of an aberrant T-cell response to EBV infection. 相似文献
83.
84.
目的:了解近年来北京市志贺菌菌型变化及毒力基因分布特征。方法:对2004年-2010年监测到的1413株志贺菌进行血清分型;应用荧光PCR方法进行ipaHs、et1和sen基因的检测。结果:宋内志贺菌741株(52.4%),福氏志贺菌664株(47.0%),痢疾和鲍氏志贺菌各4株(1.2%)。福氏志贺菌共分为19种血清型,以F4c、F2a、F1a为主。宋内志贺菌自2007年首次超过福氏成为优势菌型后,所占比例逐渐加大,2010年已达到79.3%。福氏志贺菌也逐步由F4c转向以F2a为主,并伴有其它血清型交替出现。ipaH s,et1和sen三种基因的携带率分别为95.4%,82.3%和57.5%。set1和sen在福氏志贺菌的携带率明显高于宋内志贺菌。结论:近8年北京市志贺菌菌型发生了显著变化,宋内志贺菌正逐步成为主导菌型。毒力相关基因在不同菌型的分布存在差异。 相似文献
85.
目的:研究霍乱弧菌中TLC基因簇的分子组成特征和类型检测方法的建立。方法:针对TLC基因簇内部的特征性基因设计结构相关引物和探针,利用序列比对、PCR和核酸杂交等分子生物学方法,检测并验证TLC在菌株内的基因结构和排列方式,确定分布类型。结果:pTLC与TLC基因簇之间序列有变异,TLC多整合于染色体中;建立了TLC基因簇的组成类型检测方法,并发现3种不同的结构排列方式。结论:TLC基因簇类型检测方法的建立及变异性的研究,利于深入揭示其在霍乱进化和毒力转移等过程中的影响作用。 相似文献
86.
目的分析和评价北京市原东城区乙肝疫苗阻断乙肝母婴传播的效果及影响因素,探讨科学有效的阻断方法,为制定预防乙肝母婴传播措施提供科学依据。方法通过现况调查方式,调查原东城区在册登记的母亲乙肝阳性儿童的免疫接种情况、母亲感染情况、分娩方式、喂养方式等信息,并进行乙肝感染指标及保护性抗体的血清学检测,评价乙肝疫苗阻断乙肝母婴传播的免疫效果,分析各种因素对阻断效果的影响。结果此次现况调查母亲HBsAg阳性的儿童465人,乙肝感染率5.59%,疫苗保护率为93.42%。接种血源型疫苗后的感染率24.00%,接种基因工程乙肝疫苗(重组酵母)后的感染率3.37%。接种不同种类乙肝疫苗的儿童乙肝感染率差异有统计学意义(χ2=35.965,P=0.000)。结论北京市原东城区采取乙肝母婴传播阻断措施效果显著,母亲阳性儿童乙肝感染率已降至较低水平;基因疫苗取代血源疫苗后,保护率显著提高。乙肝疫苗和HBIG联合免疫对提高疫苗保护率效果不显著;母亲感染状况是影响母婴传播阻断效果的重要因素,单阳母亲的母婴传播阻断效果优于双阳母亲;原东城区母亲阳性儿童保持了较高的抗体阳转率和抗体滴度水平。 相似文献
87.
目的 预测吉林省艾滋病高危人群规模及艾滋病病毒感染者和艾滋病病人数,为艾滋病防治工作提供依据.方法 依据吉林省哨点监测、病例报告、专题调查以及文献报道等数据,利用Workbook方法,估计2009年吉林省艾滋病疫情.结果 截止2009年底,预测吉林省存活的艾滋病病毒感染者和艾滋病病人共5668例(4262-7075例).全人群感染率为0.021%(0.016%-0.026%);其中经异性性传播2453例,占43.3%.经同性性传播2075例,占36.6%,经血液传播950例,占16.7%,经吸毒传播162例,占2.9%,经母婴传播28例,占0.5%.结论 2009年吉林省艾滋病疫情仍然处于低流行水平,性传播为主要传播途径,感染者主要集中在部分较大城市. 相似文献
88.
《Vaccine》2019,37(38):5745-5753
BackgroundIn 2012, the World Health Assembly endorsed the Global Vaccine Action Plan (GVAP) that set a target to eliminate measles and rubella in five of the six World Health Organization (WHO) regions by 2020. Significant progress has been made toward achieving this goal through intensive efforts by countries and Measles & Rubella Initiative (M&RI) partners. Accelerating progress will require evidence-based approaches to improve implementation of the core strategies in the Global Measles and Rubella Strategic Plan. The M&RI Research and Innovation Working Group (R&IWG) conducted a web-based survey as part of a process to identify measles and rubella research priorities. Survey findings were used to inform discussions during a meeting of experts convened by the M&RI at the Pan American Health Organization in November 2016.MethodsThe cross-sectional web-based survey of scientific and programmatic experts included questions in four main topic areas: (1) epidemiology and economics (epidemiology); (2) new tools for surveillance, vaccine delivery, and laboratory testing (new tools); (3) immunization strategies and outbreak response (strategies); and (4) vaccine demand and communications (demand). Analyses were stratified by the six WHO regions and by global, regional, or national/sub-national level of respondents.ResultsThe six highest priority research questions selected by survey respondents from the four topic areas were the following: (1) What are the causes of outbreaks in settings with high reported vaccination coverage? (epidemiology); (2) Can affordable diagnostic tests be developed to confirm measles and rubella cases rapidly and accurately at the point of care? (new tools); (3) What are effective strategies for increasing coverage of the routine first dose of measles vaccine administered at 9 or 12 months? (strategies); (4) What are effective strategies for increasing coverage of the second dose given after the first year of life? (strategies); (5) How can communities best be engaged in planning, implementing and monitoring health services including vaccinations? (demand); (6) What capacity building is needed for health workers to be able to identify and work more effectively with community leaders? (demand). Research priorities varied by region and by global/regional/national levels for all topic areas.ConclusionsResearch and innovation will be critical to make further progress toward achieving the GVAP measles and rubella elimination goals. The results of this survey can be used to inform decision-making for investments in research activities at the global, regional, and national levels. 相似文献
89.
Man-made magnetic fields (MFs) may exert adverse effects on mammalian embryonic development. Herein, we analysed the effect of 10 mT 50 Hz sinusoidal (AC) or static (DC) MFs versus 1 mT MFs on embryonic development of mice. Exposure for 20 days during gestation to 10 mT MFs increased resorptions and dead fetuses, decreased crown-rump length and fresh weight, reduced blood vessel differentiation and caused histological changes, accompanied with diminished vascular endothelial growth factor (VEGF) protein expression in several organs. In embryonic stem (ES) cell-derived embryoid bodies exposure towards 10 mT MFs increased reactive oxygen species (ROS), decreased vascular marker as well as VEGF expression and enhanced apoptosis. In conclusion, our combined data from in vivo and in vitro experiments identified VEGF as an important mediator during embryonic development that can be influenced by high strength MFs, which in consequence leads to severe abnormalities in fetus organs and blood vessel formation. 相似文献
90.
《Vaccine》2019,37(28):3646-3653
National Immunization Technical Advisory Groups (NITAGs) are multidisciplinary national experts who provide independent, evidence-informed vaccine policy recommendations to national health authorities. An essential NITAG function is to ensure that these decisions are grounded in the best available evidence generated through a systematic, transparent process. However, in many low- and middle-income countries (LMICs), experience with this decision making method is limited. The Task Force for Global Health manages the Partnership for Influenza Vaccine Introduction (PIVI) program in collaboration with the Centers for Disease Control and Prevention, Ministries of Health, corporate partners and others. During 2017, PIVI worked with its country partners and the World Health Organization regional and local offices to assess NITAG strengthening needs and to provide technical assistance in 7 LMIC countries (Laos Peoples Democratic Republic, Mongolia, Vietnam, Armenia, Côte d’Ivoire; Moldova and the Republic of Georgia). Our workshops supported general NITAG capacity building and the evidence-based review process using vaccines of interest to the country. For NITAGs reviewing evidence on seasonal influenza, we developed an influenza resource package to support their review and provide country-relevant information in an easy to use format. Of the seven NITAGs trained, six have applied some of the concepts learnt: revision or development of formal transparent, systematic procedures for their operations; preparation of recommendations on seasonal influenza vaccination using quality-assessed data from systematic searches and local data; and have applied the principles learned for making other new vaccine recommendations. Our experience confirms that LMIC NITAGs are considerably under-resourced without adequate technical support or access to global peer-reviewed literature. Ongoing support from NITAG partners must be secured and creative approaches might be needed to help countries achieve the GVAP 2020 target and support development of sustainable vaccine policies and programs. 相似文献