共查询到20条相似文献,搜索用时 31 毫秒
1.
通过RT-PCR对采集自河北省2个猪场的5份腹泻仔猪小肠内容物进行检测,结果均为猪δ冠状病毒(PDCoV)阳性。将病料处理后接种LLC-PK1细胞,从2个猪场的病料中各成功分离到1株PDCoV,分别命名为PDCoV CHN-HeB-A1株和CHN-HeB-B2株。通过间接免疫荧光试验(IFA)、Western blot和电镜观察对分离的病毒进一步鉴定,IFA和Western blot结果证实2株病毒都能与PDCoV M蛋白的单克隆抗体发生特异性反应,电镜下可观察到直径100~150 nm、呈典型皇冠状的病毒粒子,证实所分离的病毒为PDCoV。全基因组测序以及遗传进化分析结果表明,2株PDCoV与中国大陆毒株相似性较高,为98.7%~99.1%,与中国香港毒株处于同一簇。 相似文献
2.
乙型脑炎病毒的分离与鉴定 总被引:6,自引:1,他引:6
通过收集母猪流产死胎和蚊子为病料 ,用乳鼠脑内接毒和细胞接毒相结合的方法盲传并分离出病毒 ,进而采用血凝 (HA)实验、荧光抗体染色技术 (间接法 )、电镜实验、血清学实验及RT -PCR方法对所分离的病毒进行鉴定 ,结果表明所分离的病毒SC株为乙脑病毒 ,其PrM/E的同源性与JEV强毒株SA14相比达 98%。 相似文献
3.
Reoviruslike agent in stools: association with infantile diarrhea and development of serologic tests 总被引:39,自引:0,他引:39
A Z Kapikian H W Kim R G Wyatt W J Rodriguez S Ross W L Cline R H Parrott R M Chanock 《Science (New York, N.Y.)》1974,185(156):1049-1053
Reoviruslike particles were visualized by electron microscopy in stool filtrates prepared from stools of infants and young children with severe acute gastroenteritis. Patients who had such particles in their stools and whose paired acute and convalescent serums were tested developed an antibody response to the reoviruslike agent, which was measured by immune electron microscopy and by complement fixation. The reoviruslike agent was antigenically related to the epizootic diarrhea of infant mice virus and the Nebraska calf diarrhea virus. 相似文献
4.
Cronobacter spp. (formerly Enterobacter sakazakii) are special foodborne pathogens. Cronobacter infection can cause necrotizing enterocolitis, sepsis and meningitis in all age groups, especially neonates and infants, with a high fatality of up to 80%, although the infection is rare. Outbreaks of Cronobacter infection are epidemiologically proven to be associated with contaminated powdered infant formula (PIF). Cronobacter spp. can resist dry environments and survive for a long period in food with low water activity. Therefore, Cronobacter spp. have become serious pathogens of neonates and infants, as well as in the dairy industry. In this review, we present the taxonomy, pathogenesis, resistance, detection and control of Cronobacter spp. 相似文献
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鸡肾型传染性支气管炎病毒(IBV)的分离和某些生物学特性研究 总被引:1,自引:1,他引:0
用鸡胚传代方法从肾脏肿大的病死雏鸡分离到了两株鸡肾型传染性支气管炎病毒,命名为MK和MG,并对其某些生物学特性进行了研究。结果分离的两株病毒在电镜下表现为典型的冠状病毒形态;接种易感雏鸡能引起明显的肾脏病变;含病毒的鸡胚尿囊液经1%胰酶处理后能凝集鸡红细胞,且于接种后72~96h的活胚尿囊液血凝价较高;能干扰新城疫在鸡胚中的增殖;鸡胚半数感染量MK-6为10775/ml、MG-6为1075/ml。 相似文献
6.
Materials representing common interstratified clay minerals are shown to be composed of aggregates of fundamental particles. Transmission electron microscopy and x-ray diffraction demonstrate that the x-ray diffraction characteristics of a wide range of interstratification can be modeled experimentally by utilizing materials containing only three types of particles. The data have been incorporated into a new model that regards interstratified clay minerals as populations of fundamental particles whose x-ray diffraction patterns result from interparticle diffraction. 相似文献
7.
为研究猪源乙脑病毒分离株基因遗传稳定性,对猪源乙脑病毒分离株BSF.ZZ-1和BSF.ZZ-3在BHK-21细胞上连续传代60次后的病毒全基因组进行序列测定及分析。结果表明,BSF.ZZ-1-p60、BSF.ZZ-3-p60基因组全长均与各自的亲本毒株BSF.ZZ-1、BSF.ZZ-3一致,均为10 977 nt,在2个病毒基因组的10 701 nt位点处均插入1个碱基G。与亲本毒株相比,2个细胞传代毒株的病毒基因组经连续传代后趋于稳定,均有10个位点发生氨基酸突变,这些突变主要集中在E蛋白区域。核苷酸序列同源性比对分析发现,与其他JEV参考毒株相比,BSF.ZZ-1-p60和BSF.ZZ-3-p60与弱毒疫苗株SA14-14-2的核苷酸序列同源性较高,分别为99.6%和95.9%,其氨基酸序列与猪源野毒分离株SH0601和HW的氨基酸序列同源性较高,分别为98.2%、86.4%和98.3%、86.5%。 相似文献
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单抗夹心ELISA检测免疫鸡群新城疫病毒 总被引:3,自引:0,他引:3
用SPF鸡胚将送检的免疫鸡群泄殖腔棉拭样品盲传一代,再用新城疫单抗夹心ELISA对F1代尿囊液进行新城疫病毒(NDV)快速检测,同时用世界动物卫生组织(OIE)推荐的NDV分离及鉴定的方法加以验证。通过对3423份样品的检测,检出阳性样品453份,阴性样品2959份,可疑样品11份,两种方法的阳性符合率为99.3%,阴性符合率为99.7%。对全部阳性样品进行病毒分离,经血凝(HA)和血凝抑制(HI)试验证明均含有新城疫病毒(NDV),再将全部阳性样品分离物进一步作毒力鉴定,结果有强毒力株、中等毒力株及弱毒力株,因此用新城疫单抗夹心ELISA检测免疫鸡群泄殖腔棉拭样品F1代尿囊液新城疫病毒快速、准确率高,呈阳性者不全是NDV强毒力株感染,还有NDV中等毒力株或弱毒力株感染。 相似文献
10.
从河北、天津、北京等省市发病鸡群中分离到8株有血凝性的分离物,其血凝作用可被新城疫阳性血清所抑制,而不能被AIV(H9亚型)、EDS76阳性血清所抑制,表明8株分离物均为新城疫病毒。利用鸡胚终点稀释法对这8株NDV进行了克隆。对8株NDV的毒力指数(MDT、ICPI、IVPI)测定结果显示:MDT在42 9~49 5h之间,ICPI在1 95~2 00之间,IVPI在2 68~2 89之间。表明8株NDV均为新城疫病毒强毒株,其毒力与标准强毒株F48E8相近。各分离毒株经2%磷钨酸负染后,电镜下观察,可见丝状、圆形或不规则形态的病毒粒子,表面有纤突样结构。各毒株的大小不尽相同,粒子直径或长轴在100~500nm之间。 相似文献
11.
Andreae MO Charlson RJ Bruynseels F Storms H VAN Grieken R Maenhaut W 《Science (New York, N.Y.)》1986,232(4758):1620-1623
Individual aerosol particles from the remote marine atmosphere were investigated by scanning electron microscopy and electron microprobe analysis. A large fraction of the silicate mineral component of the aerosol was found to be internally mixed with sea-salt aerosol particles. This observation explains the unexpected similarity in the size distributions of silicates and sea salt that has been observed in remote marine aerosols. Reentrainment of dust particles previously deposited onto the sea surface and collision between aerosol particles can be excluded as possible source mechanisms for these internally mixed aerosols. The internal mixing could be produced by processes within clouds, including droplet coalescence. Cloud processes may also be responsible for the observed enrichment of excess (nonsea-salt) sulfate on sea-salt particles. 相似文献
12.
【目的】明确猪流行性腹泻病毒(PEDV)变异株的遗传进化关系及变异株各亚型间的抗原性差异位点,为PEDV新型疫苗及诊断试剂盒的研发打下基础。【方法】将采集的3份PEDV阳性仔猪肠道组织样品接种至非洲绿猴肾细胞(Vero)上进行PEDV分离,分别采用间接免疫荧光试验(IFA)、Western blotting、RT-PCR和电镜观察进行鉴定,通过TCID50测定病毒滴度及绘制病毒体外增殖动态曲线;将分离毒株基因组分成33段进行RT-PCR扩增,使用Lasergene中的SeqMan拼接序列,然后以MEGA 7.0进行遗传进化分析,并以Protean中的Jameson-Wolf算法进行抗原性分析。【结果】其中1份PEDV阳性仔猪肠道组织样品在Vero细胞上盲传至第6代时出现典型的细胞病变,将其命名为CH-HK-2021毒株;IFA和Western blotting鉴定结果表明CH-HK-2021毒株能与小鼠抗PEDV N蛋白单克隆抗体发生特异性反应,且RT-PCR能扩增获得预期的目的条带,证实分离毒株即为PEDV。CH-HK-2021毒株的直径在80~120 nm,且病毒粒子表面带有刺突样... 相似文献
13.
McMorran BJ Agrawal A Anderson IM Herzing AA Lezec HJ McClelland JJ Unguris J 《Science (New York, N.Y.)》2011,331(6014):192-195
Electron beams with helical wavefronts carrying orbital angular momentum are expected to provide new capabilities for electron microscopy and other applications. We used nanofabricated diffraction holograms in an electron microscope to produce multiple electron vortex beams with well-defined topological charge. Beams carrying quantized amounts of orbital angular momentum (up to 100?) per electron were observed. We describe how the electrons can exhibit such orbital motion in free space in the absence of any confining potential or external field, and discuss how these beams can be applied to improved electron microscopy of magnetic and biological specimens. 相似文献
14.
Human rotavirus type 2: cultivation in vitro 总被引:54,自引:0,他引:54
R G Wyatt W D James E H Bohl K W Theil L J Saif A R Kalica H B Greenberg A Z Kapikian R M Chanock 《Science (New York, N.Y.)》1980,207(4427):189-191
A strain of type 2 human rotavirus (Wa) was grown to relatively high titer through 14 passages in primary cultures of African green monkey kidney (AGMK) cells. This passage series was initiated with virus that had been passaged 11 times serially in newborn gnotobiotic piglets. In contrast, virus present in the stool of patient Wa as well as virus from the first, second, or third passage in piglets could not be propagated successfully in African green monkey kidney cells. Prior to each passage in cell culture, the virus was treated with trypsin and the inoculated cultures were centrifuged at low speed. Cultivation of a type 2 human rotavirus should aid attempts to characterize this virus and to develop a means of immunoprophylaxis for a serious diarrheal disease of human infants. 相似文献
15.
试验从健康仔猪肠道内容物内分离筛选具有抗猪传染性胃肠炎病毒(Transmissible gastroenteritis coronavirus,TGEV)活性的益生菌。从健康仔猪肠道内容物内分离获得69株乳酸菌,通过致细胞病变(CPE)作用初步筛选出18株具有影响TGEV致细胞病变的乳酸菌,在体外试管平台上,将获得的18株乳杆菌分别与定量的TGEV感作后取上清,将病毒上清感染ST细胞,运用MTT比色法测定候选菌株对TGEV感染ST细胞的抑制作用。结果表明,18株中的2株益生菌对TGEV感染ST细胞有显著的抑制作用,其他16株对TGEV感染ST细胞的抑制作用不显著。对2株具有显著作用的益生菌进行生化鉴定及16SrRNA鉴定,最终确定为罗伊氏乳杆菌和发酵乳杆菌。 相似文献
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Polycrystalline samples of the chalcopyrites CulnS(2), CulnSe(2), and CulnSSe were Prepared from stoichiometric mixtures of the pure elements by microwave irradiation. The reactions were performed in sealed quartz tubes in as few as 3 minutes. The products were analyzed by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray analysis, and x-ray photoelectron spectroscopy. The surface morphology and shape of the particles produced by this method suggest that the products are formed from liquid melts. This method could be applied to the production of bulk chalcopyrite as sources for thin film growth. 相似文献
18.
将三对抗不同药物的 Eimeria tenella 虫株(氯嗪苯乙氰抗性株与盐霉素抗性株、氯嗪苯乙氰抗性株与氯羟吡啶抗性株、氯嗪苯乙氰抗性株与拉沙里菌素抗性株)分别等量混合感染不给药的鸡只,获得各自的杂交一代 F_1.再用 F_1感染饲喂双重药物的鸡只,通过双重药物的筛选,分别获得了各自的 E.tenella抗药性重组株 F_2~(ds),F_2~(de),F_2~(dl).这3株抗药性重组株在 F_2代中所占比例分别为:19.9%,36.5%,26.7%,重组株对相关的两种药产生了完全的抗药性.试验结果还显示,重组株的致病力与 E.tenella 敏感株无明显差异. 相似文献
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从一育肥猪早、中期生产状况差的猪场收集猪血清214份,采用猪细小病毒(PPV)特异性检测引物进行PCR检测,选取1份阳性血清接种猪睾丸细胞(ST)进行PPV分离、部分生物学特性研究,以及PPV部分基因序列分析。结果表明:在15、16、17、18、22周龄猪血清中均检测到PPV,检测阳性率分别为10%、40%、20%、15.4%、9%,而从2~14及24周龄的猪血清中没有检测到PPV;病毒分离和部分生物学特性研究结果表明,从血清中分离的PPV在ST细胞上传到第5代能够出现较稳定的细胞病变(CPE),病毒血凝效价为28;PPV部分基因序列与GenBank收录的PPV毒株序列同源性在98%以上,其中与2012年西北农林科技大学时乐[1]分离的YL毒株同源性高达99.1%。以上结果证实本研究分离到PPV,且说明PPV在采样猪场的保育后期和育肥前、中期猪血清中具有较高的阳性率。 相似文献
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于典型烟草丛枝病病株上采集的蚜虫,经布安氏固定液及戊二醛固定液固定,次甲兰染色或不染色。取其唾液腺,经常规戊二醛、锇酸双重固定,丙酮脱水,Epon812包埋,聚合,超薄切片,电子染色后,于电镜下观察。在蚜虫唾液腺细胞内观察到大量烟草丛枝病病原MLO的聚集。健康烟株上饲养的第2代蚜虫唾液腺细胞内未检测到类似病原。 相似文献