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1.
根据猪繁殖与呼吸综合征病毒(PRRSV)美洲型标准毒株(ATCCVR-2332)的ORF6及部分ORF7的序列,设计合成了一对引物26374PS/26375PR,用反转录聚合酶链反应(RTPCR)技术对6株PRRSV北京分离株进行了检测。结果该引物对6株病毒均能扩增出与预期大小相符的RTPCR产物,并与ATCCVR2332株扩增产物的大小相当,而欧洲型标准毒株(LV株)未获扩增片段。进一步用限制性内切酶进行酶切分析,发现这6株病毒及ATCCVR-2332的PCR产物皆出现相同的限制性酶切图谱,证实6株病毒均为PRRSV。  相似文献   
2.
应用反转录-聚合酶链反应(RT-PCR)技术检测了猪和牛的扁桃体、淋巴结、脊髓、肌肉和蹄冠皮肤中的口蹄疫病毒(FMDV)。与接种乳鼠测毒法比较,该方法的灵敏度达0.16LD50~0.32LD50病毒量。检测人工感染后7~35d的猪组织样品77份,25份为阳性;接种乳鼠并盲传3代,乳鼠-间接血凝试验(IHA)鉴定6份为阳性。检测人工感染后4~7d的牛组织样品52份,20份为阳性;接种乳鼠-IHA鉴定12份为阳性。检测野外鲜肉样品47份,12份为阳性;任选其中8份样品接种细胞单层,盲传至第6~7代,先后有5份样品产生CPE;其中6份样品同时接种乳鼠,盲传至第6~7代,3组乳鼠出现FMDV致病症状,IHA鉴定为阳性。检测冻猪肉样品37份,3份为阳性;冻牛肉样品9份、冻羊肉样品10份,均为阴性  相似文献   
3.
Small scale digital device forensics is particularly critical as a result of the mobility of these devices, leading to closer proximity to crimes as they occur when compared to computers. The Windows Surface tablet is one such device, combining tablet mobility with familiar Microsoft Windows productivity tools. This research considers the acquisition and forensic analysis of the Windows Surface RT tablet. We discuss the artifacts of both the Windows RT operating system and third-party applications. The contribution of this research is to provide a road map for the digital forensic examination of Windows Surface RT tablets.  相似文献   
4.
采用RT PCR方法扩增了鸡传染性支气管炎病毒D971毒株预期的 163 6bp的S1全基因DNA片段 ;以Sanger’s双脱氧末端终止法测定出其核苷酸序列 ,推导出了氨基酸序列 ,并用有关软件构建了S1基因进化树。结果表明 ,IBV D971毒株与国内外AF14 0 3 5 2 (山东农业大学 )、AF15 4841(山东农业大学 )、AF193 43 2 (青岛动物检疫所 )、AY0 43 3 12 (中国农业大学 )、AF3 975 2 8(四川农业大学 )、AY0 43 2 2 1(浙江农业大学 )、AF3 5 2 3 12 (浙江农业大学 )、U2 95 2 2 (澳大利亚 )和M2 1883 (英国 )毒株的核苷酸同源性分别为 99%、99%、95 %、94%、87%、86%、88%、82 %和 80 % ,氨基酸序列同源性依次分别为 93 %、93 %、87%、86%、83 %、83 %、82 %和 80 %。  相似文献   
5.
Many countries now operate state-funded international broadcasters, communicating directly with foreign publics to promote a variety of foreign policy goals. RT (formerly known as Russia Today) is currently one of the most prominent broadcasters in a crowded field. What is RT’s strategy, the size of its audience, and the effectiveness of its broadcasts in implementing its strategy? To answer these questions, we explore a case study of RT’s YouTube programming utilizing a new dataset of 70,220 video titles spanning the 2 years from February 2015 through January 2017. RT’s three-prong strategy focuses attention on strategic groups outside the West, including Arabic, Russian, and Spanish speakers, circumvents local media in target countries to promote Kremlin aims, and spreads a positive image of Russian accomplishments, particularly in Syria, which it considers a foreign policy success. The data presented here show that RT’s strategy is only partially successful since it underperforms among Arabic speakers, its main target, while doing relatively better among Russian, global English, and Spanish audiences.  相似文献   
6.
禽呼肠孤病毒S1基因的扩增克隆与鉴定   总被引:1,自引:0,他引:1  
  相似文献   
7.
将我国新城疫强毒株F48E9在SPF鸡胚增殖后提取RNA,用自行设计的一对寡聚核苷酸引物进行RT-PCR,合成了F糖蛋白基因片段。将此片段与pUC19质粒重组,转化大肠杆菌JM109,从阳性克隆中提取重组质粒,再用PCR法扩增,获得了同样大小的DNA片段。经用特异性抗体探针检测,证明该片段在大肠杆菌中的表达产物具有良好的抗原性  相似文献   
8.
利用反转录套式聚合酶链反应(RTnestedPCR)技术从北京地区3株鸡传染性支气管炎病毒(IBV)分离株(BJ1,BJ2,BJ3)中扩增出1054bpS1基因高变区。利用限制性内切酶SinⅠ和PstⅠ的酶切位点分析图谱进一步证实了RTnestedPCR的特异性。将3段S1基因分别克隆到pUC19质粒中,获得重组质粒pUCIBVS1BJ1,pUCIBVS1BJ2和pUCIBVS1BJ3。  相似文献   
9.
The ability to determine vitality and estimate the survival period after a wound is critical in routine forensic practice. The mRNA levels of MMP‐2 and TIMP‐2 were examined using quantitative real‐time RT‐PCR to determine the age of a wound. Furthermore, the colocalization of them with Macrophage Marker, respectively, was detected by double immunofluorescence, and a standardized rat model of skeletal muscle contusion was established. In the antemortem contused groups, a large number of macrophages showed positive staining for MMP‐2 and TIMP‐2, and the expression of MMP‐2 and TIMP‐2 mRNA increased sharply at 3 days postinjury, with relative quantities of 5.75 and 2.98. No samples in the other groups showed relative quantities of >5.75 and 2.98; therefore, relative quantities exceeding 5.75 and 2.98 were strongly indicated 3 days after contusion. In addition, there was a significant decrease in the relative quantity in the postmortem contused groups, indicating that they were useful for diagnosing vitality.  相似文献   
10.
利用鸡胚分离法由发生肾病变型传染性支气管炎 (IB)的病鸡分离到嗜肾型传染性支气管炎病毒 (NIBV)W株 ;再通过SPF鸡胚连续传代 ,获得了NIBV疫苗毒株W93;继而借助RT PCR法扩增了其S1基因 ,并测定了S1基因的核苷酸序列 ,分析了与相关毒株间的同源性。结果显示 ,W93株在鸡胚中的病毒产量达 10 7.8EID50 /0 .1mL ,适用于所有日龄的雏鸡 ;W93S1基因的核苷酸序列与马萨诸塞型的M4 1株、H52 株和H12 0 株的同源性很高 ,分别为 96 .9%、96 .8%和 97.1%。表明 ,W93可作为制备IB弱毒疫苗的毒株  相似文献   
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