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991.
目的:探讨六安市手足口病患者中EV71的流行趋势及其基因特征,为手足口病的进一步防控提供科学依据。方法:六安市疾控中心从手足口病患儿中采集咽拭子标本进行肠道病毒核酸检测,选取其中8份EV71核酸阳性标本进一步进行VP1全基因序列测定,结果使用Bioedit和DNA Star软件与世界各地EV71各型参考株及我国大陆的EV71流行株序列进行对比分析,构建种系进化树。结果:8株病毒核酸VP1基因全长均为891个核苷酸,编码297个氨基酸,与我国大陆分离的C4a基因型最为相近,核苷酸同源性在96.7%~99.4%之间,氨基酸同源性在97.0%~100%之间;而与A、B基因型参考株差异较大,核苷酸同源性分别为82.6%~83.2%、83.1%~85.0%;氨基酸同源性分别为96.6%~97.0%、96.0%~97.7%;说明本文的8株病毒均属于EV71 C4a基因型。结论:六安市2010年EV71流行株在种系进化上与我国大陆近几年分离的毒株具有较高的同源性,同属于C4a基因型,目前C4a亚型病毒在我国大陆可能有较广泛的分布和传播。本研究对于肠道病毒的基础研究和防范EV71在中国的大规模暴发与流行具有重要意义. 相似文献
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目的:观察抗肿瘤药物氟尿嘧啶(5-fluorouracil,5-FU)、阿霉素(Adriamycin,ADM)联合X线外照射对人乳腺癌MCF-7细胞Livin基因表达的干扰效应及对细胞凋亡的影响.方法:用MTT法分别测定5-FU、ADM 2种药物作用MCF-7细胞72 h的半数抑制浓度(Half maximal inh... 相似文献
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LaBeaud AD Sutherland LJ Muiruri S Muchiri EM Gray LR Zimmerman PA Hise AG King CH 《Emerging infectious diseases》2011,17(2):233-241
Few studies have investigated the many mosquito species that harbor arboviruses in Kenya. During the 2006-2007 Rift Valley fever outbreak in North Eastern Province, Kenya, exophilic mosquitoes were collected from homesteads within 2 affected areas: Gumarey (rural) and Sogan-Godud (urban). Mosquitoes (n = 920) were pooled by trap location and tested for Rift Valley fever virus and West Nile virus. The most common mosquitoes trapped belonged to the genus Culex (75%). Of 105 mosquito pools tested, 22% were positive for Rift Valley fever virus, 18% were positive for West Nile virus, and 3% were positive for both. Estimated mosquito minimum infection rates did not differ between locations. Our data demonstrate the local abundance of mosquitoes that could propagate arboviral infections in Kenya and the high prevalence of vector arbovirus positivity during a Rift Valley fever outbreak. 相似文献
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Background
A trivalent, Ann Arbor strain, live attenuated influenza vaccine (LAIV) is approved for use in children 24 months of age and older in a number of countries. The incidence, duration, and other parameters of viral shedding after vaccination with LAIV have not been fully described in children ≤5 years of age.Methods
An open-label, single-arm, multicenter, phase 2 study assessed viral shedding and safety in 200 children 6-59 months of age after a single, intranasal dose of LAIV in 2006. Participants were enrolled into 2 age groups: 6-23 months (n = 100) and 24-59 months (n = 100) of age. Viral shedding, reactogenicity, and adverse events were assessed for 28 days postvaccination. Serious adverse events and significant new medical conditions were monitored for 180 days postvaccination.Results
Viral shedding was detected by culture in 79% (95% CI, 73-84) of vaccine recipients and occurred more frequently in children 6-23 months of age (89%) compared with children 24-59 months of age (69%). In total, 157 subjects shed vaccine, which was confirmed by RT-PCR as A/H1N1 for 128 subjects, A/H3N2 for 72 subjects, and B for 74 subjects. The incidence of shedding was highest on day 2 (59% in the 6-23 month age group; 41% in the 24-59 month age group) and most shedding occurred 1-11 days postvaccination; shedding after 11 days was infrequent and occurred almost exclusively in children 6-23 months of age. Mean titers of shed vaccine virus peaked on day 2 and were generally <103.0 median tissue culture infective dose/mL for both groups. Reactogenicity events peaked on day 2; runny/stuffy nose was reported most frequently (63% of all subjects).Conclusion
Most children 6-59 months of age vaccinated with Ann Arbor strain LAIV shed ≥1 vaccine virus within 11 days of vaccination. Shedding was less common in children 24-59 months of age, a population for whom LAIV is approved for use. Titers of shed vaccine were low, which may explain why secondary transmission of LAIV was observed very infrequently in a previous controlled study conducted with young children in a daycare setting. 相似文献996.
目的:研究IFITM1基因转染对子宫颈癌HeLa细胞的影响,以及抑制子宫颈癌HeLa细胞生长的作用。方法:应用脂质体法介导IFITM1基因转染子宫颈HeLa细胞,用RT-PCR方法、免疫荧光法、MTT法及流式细胞术检测IFITM1基因转染HeLa细胞的生物学特性。结果:转染后的HeLa细胞:①RT-PCR检测及激光共聚焦显示重组质粒组中mRNA及蛋白表达含量明显高于对照组及空载体组,而对照组及空载体组蛋白表达无统计学差异。②MTT结果显示重组质粒组细胞存活率均明显低于空载体组及未转染HeLa细胞组,而后两组无统计学差异。③AnnexinV/PI双色流式细胞仪检测表明,重组质粒组的HeLa细胞凋亡水平明显高于空载体组和未转染HeLa细胞组,有统计学差异。结论:IFITM1蛋白与子宫颈鳞癌有着密切的关系,该基因可能是一种潜在的抑制子宫颈鳞癌发生的基因。 相似文献
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《The Journal of allergy and clinical immunology》2019,143(6):2202-2214.e5
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