The research indicates that there is a positive correlation between the negative CG flash rate and the area of radar echo with its reflectivity being equal to or greater than 30 dBz in the mesoscale convective system ...The research indicates that there is a positive correlation between the negative CG flash rate and the area of radar echo with its reflectivity being equal to or greater than 30 dBz in the mesoscale convective system in Beijing area.A max- imum of the positive CG flash rate exists at both the initial and the dissipating stages.The CG flashes are usually located near but not within the high reflectivity center.The negative flashes are associated with.the positions of the updraft re- gion,and with the regions of wind convergence and wind shear.Generally,the negative CG flashes are concentrative and the positive ones are dispersive.展开更多
应用表达纯化的小反刍兽疫病毒(peste des petits ruminants virus,PPRV)N蛋白制备的多克隆抗体,建立了检测PPRV抗原的双抗体夹心ELISA方法,并对吉林省和内蒙古地区羊群感染PPRV进行了调查。方阵法确定了抗PPRV兔源IgG作为捕获抗体的包...应用表达纯化的小反刍兽疫病毒(peste des petits ruminants virus,PPRV)N蛋白制备的多克隆抗体,建立了检测PPRV抗原的双抗体夹心ELISA方法,并对吉林省和内蒙古地区羊群感染PPRV进行了调查。方阵法确定了抗PPRV兔源IgG作为捕获抗体的包被量为0.2μg,酶标抗体的最佳稀释度为1∶1 000。对大量小反刍兽疫阴性粪便样品进行检测及统计学处理,确定了双抗体夹心ELISA检测PPRV的判定标准,即被检粪便样品D490≥0.221,判定为阳性。特异性、敏感性等试验结果表明,建立的检测PPRV抗原方法具有特异、敏感和快速等优点。与RT-PCR方法相比,该方法省时省力、简单快速。应用建立的检测PPRV抗原的双抗体夹心ELISA对吉林省和内蒙古不同地区的羊粪样进行检测,发现羊群均存在程度不同的PPRV隐性感染。本研究在国内首次揭示出临床健康羊群携带PPRV,为今后小反刍兽疫的诊断与防控提供了新的流行病学理论依据。展开更多
基金supported by grants from State Planning Commission under Grants No.75-09-02-19
文摘The research indicates that there is a positive correlation between the negative CG flash rate and the area of radar echo with its reflectivity being equal to or greater than 30 dBz in the mesoscale convective system in Beijing area.A max- imum of the positive CG flash rate exists at both the initial and the dissipating stages.The CG flashes are usually located near but not within the high reflectivity center.The negative flashes are associated with.the positions of the updraft re- gion,and with the regions of wind convergence and wind shear.Generally,the negative CG flashes are concentrative and the positive ones are dispersive.
