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1.
为深入研究血清4型禽腺病毒广西分离株的致病机理,对4周龄的SPF鸡人工感染血清4型禽腺病毒(FAdV-4),建立病理模型,在感染后第1~21天随机剖杀试验组的SPF鸡,采集心脏、肝、脾、肺、肾、胸腺、法氏囊、胰腺、腺胃和脑,通过病理学方法研究FAdV-4感染SPF鸡后各个组织器官的动态病理变化规律。结果显示,以滴鼻点眼方式感染4周龄SPF鸡可以成功建立人工感染模型。感染后第4天开始出现临床症状,第5天开始出现死亡,第7天病鸡开始恢复,发病率为72%,死亡率为34%。剖检发现典型病变为心包积液,肝肿大、黄染。组织学检查发现肝细胞中存在大量核内包涵体,免疫器官出现广泛性的组织变性坏死、炎性细胞浸润。本研究为FAdV-4的防控和临床诊断提供了科学依据,为今后深入研究FAdV-4的致病机制奠定了基础。  相似文献   

2.
为探明腺胃型传染性支气管炎病毒(IBV)对鸡的致病性,采用滴鼻、点眼和滴口方法,用QXIBV、DYIBV、FCIBV分离毒株对未免疫鸡和SPF鸡进行了攻毒致病回归试验。结果显示,未免疫的10日龄鸡攻毒后致死鸡的剖检变化与20日龄未免疫的被攻毒鸡相似,均有腺胃肿大,腺胃黏膜出血、溃疡,肾肿大、尿酸盐沉积等病变;20日龄(高日龄)攻毒鸡较低日龄(10日龄)攻毒鸡死亡率偏高。被攻毒的SPF鸡均出现精神沉郁、羽毛蓬乱、腹泻等与自然发病鸡相同的临床症状和病理变化(腺胃肿大,黏膜出血、溃疡,肾肿大、尿酸盐沉积等病变);被攻毒的未免疫鸡、SPF鸡与自然发病鸡死亡率相似。试验结果表明,用这3株腺胃型IBV分离株均能人工复制出与自然发病鸡基本一致的临床症状和病理变化。  相似文献   

3.
选取从临床感染禽Ⅰ型副黏病毒(APMV-1)的鸡、鹅、鸽、鹌鹑、珍珠鸡、孔雀、画眉鸟等7种禽类病例分离到的9个代表性毒株,分别对鸡、鹌鹑、鹅和鸽进行了人工感染试验。结果,除鸽源毒株gxp22对鸡和鹅无致病力外,其他8个分离毒株对鸡、鹌鹑和鹅都有较强的致病力,死亡率为60%~100%,试验鸡表现的症状和病理变化特征最明显,鹅的比较明显,鹌鹑的则最不明显;3个鸽源分离株对鸽的致病力都很强,死亡率均为100%。所有毒株对4种禽类的致病性与其临床特征相符。研究结果表明,试验所用的9个分离株除鸽源分离株gxp22外,均为泛嗜性的新城疫强毒株。  相似文献   

4.
鸡传染性支气管炎病毒的分离鉴定及其致病性的研究   总被引:1,自引:0,他引:1  
本研究从江苏省某鸡场疑似鸡传染性支气管炎(IB)的病料中,利用SPF鸡胚尿囊腔接种的方法分离出1株传染性支气管炎病毒(IBV),命名为CK/CH/JS/TZHY48。经RT-PCR检测,该株IBV的S1基因全长1 638 bp。遗传进化分析显示,分离株属于基因Ⅵ型,与常规疫苗株H120和H52的同源性较远。分离株对鸡胚有明显的致矮小化作用;对新城疫病毒有显著的干扰作用。动物回归试验结果显示,该分离株对7日龄SPF鸡的发病率为100%,致死率为40%,发病鸡出现气管啰音,甩头流鼻涕等呼吸道症状;病死鸡的剖检病理变化主要表现为肾苍白肿大,花斑肾,有大量明显的白色尿酸盐沉积,气管环出血。本研究可为IBV的遗传进化、致病机制以及免疫防控提供参考。  相似文献   

5.
以 5株鸡传染性支气管炎病毒 (IBV )疫苗株 (D41、H12 0GD、H12 0SH、H5 2BJZH和H5 2GD株 )和IBV标准强毒M 41E4株的基因组RNA为模板 ,利用RTPCR技术 ,扩增出 1条特异性条带 ,包括部分核衣壳蛋白 (N)基因以及紧接着N基因下游的基因组 3′端非编码区 (UTR)。测序结果表明 ,从D41、H12 0GD和H12 0SH株扩增的特异性片段长度为6 14 2bp ;而从H5 2BJZH、H5 2GD和M 41E4株扩增的特异性片段长度为 40 6 2bp。序列分析发现 ,被检的 6株IBV毒株可分两组 ,其中D41、H12 0GD和H 12 0SH株为一组 ,核苷酸序列同源性为 99.7?.8%;而H5 2BJZH、H5 2GD和M 41E4株构成另一组 ,其核苷酸序列同源性为 99.3 0 %;两组之间的最大同源性仅为 94.6 %。在系统发生进化树上 ,这两组分别位于不同的分支簇上 ,国内的H5 2BJZH、H5 2GD与国外的H5 2株不在同一分支簇上 ,相反却与国内强毒M 41E4株以及国外M 41株在同一分支簇上。提示国内H5 2疫苗株与国外H5 2疫苗株不同 ,它们在亲缘关系上更靠近M 41E4株和M 41株。  相似文献   

6.
从天津市某肉用鸡场疑似肾型传染性支气管炎(NIB)病鸡中取肾组织,按常规处理后接种9-10日龄鸡胚,连续传代培养至第7代,并对4-7代分离毒株的致病性、血凝性、EID50及对DNV的干扰性和乙醚敏感性进行测试,同时进行了动物回归试验.结果表明,4-7代分离毒株可使85%-90%鸡胚于接种后8-9 d死亡,多数死胚和残存活胚胚体出血、蜷缩、矮化等具有IBV感染特征;该分离毒株无直接血凝性,但经10 g/L胰酶处理后可凝集鸡红细胞;分离毒株对乙醚敏感;动物回归试验中有65%的感染鸡在15 d内发病或死亡.剖检病死鸡可见肾苍白、肿胀,肾小管内充塞大量尿酸盐,外观呈菜花样.经鉴定,分离的病毒株JH9801为鸡肾型传染性支气管炎病毒(NIBV).  相似文献   

7.
以5株鸡传染性支气管炎病毒(IBV)疫苗株(D41、H120GD、H120SH、H52BJZH和H52GD株)和IBV标准强毒M41-E4株的基因组RNA为模板,利用RT-PCR技术,扩增出1条特异性条带,包括部分核衣壳蛋白(N)基因以及紧接着N基因下游的基因组3′端非编码区(UTR).测序结果表明,从D41、H120GD和H120SH株扩增的特异性片段长度为614 bp;而从H52BJZH、H52GD和M41-E4株扩增的特异性片段长度为406 bp.序列分析发现,被检的6株IBV毒株可分两组,其中D41、H120GD和H120SH株为一组,核苷酸序列同源性为99.7%~99.8%;而H52BJZH、H52GD和M41-E4株构成另一组,其核苷酸序列同源性为99.3%~100%;两组之间的最大同源性仅为94.6%.在系统发生进化树上,这两组分别位于不同的分支簇上,国内的H52BJZH、H52GD与国外的H52株不在同一分支簇上,相反却与国内强毒M41-E4株以及国外M41株在同一分支簇上.提示国内H52疫苗株与国外H52疫苗株不同,它们在亲缘关系上更靠近M41-E4株和M41株.  相似文献   

8.
用RT PCR扩增了鸡传染性支气管炎病毒 (IBV)SC株S1基因 ,连接到 pMD 18 T载体上 ,克隆后进行了核酸序列分析 ,证实SC株S1基因与基因库中收录的国外毒株H12 0和M 4 1的同源性较低 ,分别为 81.1%和 80 .0 % ,而与国内JX990 1株的同源性达到 91.3% ,初步证实国内存在IBV新毒株。  相似文献   

9.
鹅源新城疫病毒感染鸡的临诊症状及病理变化   总被引:1,自引:0,他引:1  
用鹅源新城疫病毒BY株人工感染 2 5日龄雏鸡 ,同时用鸡新城疫病毒标准强毒F4 8E8株作为攻毒对照 ,观察 2株病毒感染鸡的临诊症状、病理变化 ,并加以比较。结果 ,2株病毒都可致试验鸡 1 0 0 %发病和死亡。BY组鸡于感染后 5 1h出现症状 ,发病后 4 8h全部死亡 ,主要大体病变为喉头严重出血、腺胃乳头或腺胃与肌胃交界处轻微出血、肠道黏膜局灶性出血坏死 ,病理组织学变化主要为消化器官和免疫器官内的细胞显著变性、坏死及出血等 ;F4 8E8组鸡于感染后 72h出现症状 ,发病后 36h感染鸡全部死亡 ,所表现的病理变化与BY组鸡相似 ,但腺胃和肠道的出血病变比BY组鸡显著  相似文献   

10.
本研究旨在观察无乳链球菌自然感染病兔的病理形态学变化,为探讨该菌的致病机理奠定基础。对四川省某家兔养殖场自然感染无乳链球菌家兔的病料进行了病理剖解、组织病理学观察、透射电镜观察和组织中病原菌的原位PCR检测。结果显示,病兔的主要临床特征为:站立不稳、四肢划动、惊厥并伴有呼吸障碍;解剖时见心外膜出血,肺水肿、出血;肝、脾和肾肿大,坏死;脑膜充血,脑回肿胀,脑沟变浅等。镜检时全身组织器官广泛性水肿、出血、变性、坏死和炎症反应,特别是肝、脾、肾、脑和肺损伤较为严重,分别表现为变质性肝炎、急性脾炎、间质性肾炎、脑膜脑炎和出血性肺炎。超微结构上,病兔肝、脾、肾、脑、心和肺等器官的细胞超微结构都有较为严重的损伤,细胞发生明显的病变,线粒体肿胀,嵴断裂溶解,核染色质浓缩边集,并在多组织病变的细胞内发现无乳链球菌入侵。间接原位PCR检测发现,感染家兔各个组织器官均可见不同强度的阳性信号,以胃、肝、脾、肾和小脑等组织最强,同时在心、肺和大脑中也出现相对较强的阳性信号。上述研究结果明确了无乳链球菌感染家兔的病理形态学变化特征,为进一步探讨该菌的发病机制奠定了基础。  相似文献   

11.
In this paper, the author has made a thorough study over the new generation of American China Watchers. Most of the pages are devoted to a detailed comparison between the old generation and the young generation of American China Watchers regarding to their background, education, and views over China. At the end of the paper, the author also gives some policy suggestions for both the Chinese and U.S. government based on the findings in this study.  相似文献   

12.
the U.S. is directly impacting on the future of the East Asian community. Therefore, finding ways to get along with the U.S. is crucial to the speed, direction, configuration and character of the East Asian community. In this paper, the author has analyzed the interests of the United States in East Asia and its stands towards the East Asian integration. The author concludes that it is to the interest of the United States to make more efforts to further join in the East Asian integration. And East Asia should accept and welcome the American participation.  相似文献   

13.
正The new central leadership has highlighted the strategic importance of better relations with neighboring countries and the construction of a solid foundation for China’s neighborhood strategy so as to create favorable conditions for Chinese development.1China is strengthening top-level strategy in foreign relations,focusing on global-level relations and staying committed to relations  相似文献   

14.
正Ruicheng Group was founded in Qiqihar,a city located in one of the three major ‘Chernozem belts’ in the world,the fertile Songnen Plain,and one known as the ‘home of red-crowned cranes’ Over the years,our business developed from being only one supermarket in the beginning to a corporate group operating in multiple sectors,from supermarket chain and real estate to property management and preschool education.  相似文献   

15.
China and Brazil established a strategic partnership in 1993. The bilateral ties have seen rapid development in almost all areas. However, there are eight myths surrounding the China-Brazil relations. These myths are the result of a lack of mutual understanding as well as the misconceptions result misconceptions of the western observers and media. These misunderstandings have of have jeopardized images of the China-Brazil relations and also hindered further development of their bilateral relationship.  相似文献   

16.
The successful hosting of the CICA summit has drawn great attention The attention to China's "host diplomacy". Analyzing new features of China's "host to "host diplomacy" during this new period, this paper will look at the opportunities and challenges facing China's "host diplomacy" and discuss the problems that China should address in order to do a better job in this regard and bring its "host diplomatic advantages" into full play.  相似文献   

17.
Since the beginning of the 21st century, the overall rise of the Asian geographic plate has been particularly prominently. The overall rise of Asia reflects the improvement of a large number of developing countries in Asia. The long-occupied aggressive status of the United States and Europe is weakening, and the overall rise of Asia appears more highlighted, and its impact upon the world seems more intense.  相似文献   

18.
正On the morning of April 2,2014,CAFIU held the 11th Executive Council Meeting in Beijing.Present at the Meeting were Member of the Politburo of the 17th CPC Central Committee and Vice-Chairman of the 11th CPPCC National Committee Mr.Wang Gang,ViceChairman of the 11th NPC Standing Committee and President of CAFIU Mr.Zhou Tienong,ViceChairpersons of the NPC Standing Committee Mme  相似文献   

19.
正I am very pleased to attend the 11th Executive Council Meeting of CAFIU,and would like to express my hearty congratulations to President Yan Junqi,the new leadership and the newly-elected Executive Council.I also want to express my sincere thanks for choosing me to be the Honorary President of CAFIU!  相似文献   

20.
正I.Political Parties and Government Sector Lu Yan Director,Beijing Municipal Commission of Commerce Tong Guili Member,Standing Committee of the CPC Municipal Committee of Hangzhou,Zhejiang Province Secretary,CPC Working Committee,Administrative Commission for the Sci-Tech and Innovation Industrial Park in west Hangzhou City  相似文献   

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