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1.
从临床表现呼吸道症状的病犬血液中分离获得了1株病毒,采用细胞培养、血凝及血凝抑制试验、中和试验、免疫电镜观察、免疫荧光抗体试验进行了鉴定.结果显示,该病毒能使MDCK和Vero细胞产生明显的细胞病变(CPE),能凝集人O型红细胞和猪红细胞;能被呼肠孤病毒1型血清所中和,病毒粒子呈圆形,有实心和空心两种粒子,将感染细胞用抗呼肠孤病毒1型血清及荧光抗体染色后见明显的绿色荧光.表明,所分离的病毒为呼肠孤病毒1型.  相似文献   

2.
观察了鸭源呼肠孤病毒与沙门菌共感染对雏鸭脾、法氏囊的病理损伤及法氏囊IgY抗体生成细胞数的变化,为进一步探讨鸭源呼肠孤病毒感染的发病机理和免疫防治提供理论依据。雏鸭被分成4组,即对照组、呼肠孤病毒感染组、沙门菌感染组和混合感染组,于8日龄对呼肠孤病毒感染组和混合感染组雏鸭接种鸭源呼肠孤病毒,13日龄对沙门菌感染组和混合感染组雏鸭接种鸭源沙门菌。分别于13、14、16和20日龄每组剖杀6只,观察各组脾、法氏囊和胸腺的病理变化、法氏囊IgY抗体生成细胞的数量变化特点。结果显示,呼肠孤病毒感染后脾、法氏囊和胸腺出现不同程度损伤,组织内出现明显坏死灶,之后出现肉芽肿结构,法氏囊固有层淋巴滤泡明显减少。混合感染组的病变明显重于其他单独感染组,法氏囊IgY抗体生成细胞数低于对照组。结果表明,呼肠孤病毒感染雏鸭后引起机体免疫抑制,增大了细菌的继发感染。  相似文献   

3.
为了分析禽呼肠孤病毒(ARV)S1133株感染鸡胚成纤维细胞(CEF)对细胞产生的细胞因子IL-1β、IL-6和TNF-α的影响,并探讨禽呼肠孤病毒的感染机制及病毒与宿主之间的作用关系,运用实时荧光定量RT-PCR技术,测定和分析了ARV-S1133感染CEF细胞后ARV结构蛋白σC和IL-1β、IL-6、TNF-α的动态转录水平。结果显示,ARV-S1133感染CEF后第10小时起病毒σC基因mRNA的相对表达量开始迅速上升,在第48小时达到最高峰(13 162.73倍);ARV-S1133感染后引起CEF中IL-1β、IL-6、TNF-αmRNA表达量发生变化,这3个基因mRNA的表达变化趋势相似。IL-1β、IL-6、TNF-α基因mRNA转录水平在感染早期迅速上升,在感染后第6小时达到第1个峰值,随后下降,在感染中后期再次显著上升,在第48小时达到第2个峰值。IL-1β、IL-6、TNF-α在感染后第6、24、36和48小时的mRNA转录水平与对照组差异极显著(P0.01)。结果表明,ARV感染后可诱导CEF分泌IL-1β、IL-6、TNF-α的水平上调,进而发生炎症反应,说明IL-1β、IL-6、TNF-α可能与禽呼肠孤病毒的复制和致病机制相关。  相似文献   

4.
金丝桃素可溶性粉体外抗犬瘟热病毒的试验研究   总被引:2,自引:0,他引:2  
采用先药后毒、先毒后药和药毒同加3种不同的给药方式,分别在试验开始后第72 h和96 h观察犬瘟热病毒致Vero细胞的病变情况.结果显示,犬瘟热病毒的TCID_(50)为10~(-5.68)/0.1 mL,药物的TC_0为0.312 5 g/L;与对照组比较,药物浓度在0.039~0.312 5 g/L范围内先毒后药方式的细胞生长情况良好,细胞单层完整,视野中有极少量圆细胞或死细胞,而其余两种给药方式的细胞病变明显.结果表明,金丝桃素可溶性粉在先毒后药情况下可以有效抑制犬瘟热病毒的增殖.  相似文献   

5.
将不同浓度的金丝桃素和鸡传染性支气管炎病毒(IBV)以三种方式加入鸡胚肾细胞(CEK)培养体系中,采用细胞病变效应(CPE)法、MTT法、病毒滴度法、实时荧光定量PCR以及间接免疫荧光技术检测金丝桃素体外抗IBV作用,同时检测其对IBV诱发细胞凋亡的影响。结果显示,金丝桃素在CEK细胞感染IBV前、后及同时加入,都有明显抑制CPE的作用;随着添加药物浓度的增加,CEK细胞活力明显增高,病毒TCID50滴度、病毒核衣壳蛋白RNA相对表达量和CEK细胞中病毒阳性绿色荧光信号显著降低或减少(P0.01),并且呈现明显的剂量依赖性。三种给药方式以药物和病毒互作后同时加入效果最好。IBV可以引起CEK细胞凋亡的发生,添加金丝桃素能够抑制病毒引起的凋亡。上述试验结果表明,金丝桃素具有很好的抗IBV作用,其作用可能是通过抑制感染细胞凋亡产生的,这可能是金丝桃素抗IBV的作用机制之一。  相似文献   

6.
采用RT-PCR方法扩增禽呼肠孤病毒(ARV)99G株σB编码基因,序列分析表明,99G株σB编码基因与其他禽呼肠孤病毒的同源性为90%~99 9%,而与我国番鸭呼肠孤病毒S12株的同源性仅有60%;用BarnH Ⅰ和Xho Ⅰ酶将σB编码基因切下并克隆到表达载体pGEX-6p-1中,构建了重组表达质粒pGEX-σB;鉴定后转化至大肠杆菌BL21(DE3)中,经IPTG诱导,σB基因在大肠杆菌中得到了高效表达,表达的融合蛋白占总蛋白的41.46%,融合蛋白的分子质量为66 ku,主要以包涵体形式存在;Western-blot结果显示,该融合蛋白能与抗ARV阳性血清发生特异性反应,表明重组蛋白具有良好的反应原性,可用于禽呼肠孤病毒病诊断试剂盒和基因工程疫苗的研制.  相似文献   

7.
为了探明Toll样受体(TLRs)在禽呼肠孤病毒(ARV)感染致病过程中的作用,本研究考察ARV感染鸡的不同器官中TLRs在不同感染时间点的动态表达变化。本研究将ARV S1133毒株经足垫注射,接种7日龄SPF鸡,感染后第1、3、5、7和14天采集鸡脾、腔上囊、胸腺、肝和心脏等器官组织,利用荧光定量PCR方法检测TLR3、TLR5、TLR7、TLR15和TLR21在这些器官中的m RNA表达水平变化,分析ARV感染对鸡不同器官中上述TLRs m RNA表达量的影响。结果表明,ARV可诱导TLR3、TLR5、TLR7、TLR15和TLR21在不同器官中的表达,并且表达变化也不同。在免疫器官中以TLR3和TLR7的表达升高为主,在心脏和肝中以TLR7和TLR15的表达为主。这些结果提示,TLR3、TLR5、TLR7、TLR15和TLR21在ARV感染致病过程中发挥不同的作用,本研究结果为进一步阐明禽呼肠孤病毒的致病机理奠定了基础。  相似文献   

8.
将鸭呼肠孤病毒小外壳σC蛋白编码基因克隆于原核表达载体pET32a上,经EcoRⅠ和SacⅠ双酶切鉴定及序列分析,获得了重组质粒pET32a-σC,转化DH5α大肠埃希氏菌感受态细胞后,经SDS-PAGE和Western-blotting分析,融合蛋白能够与番鸭呼肠孤病毒感染康复鸭血清发生特异反应;以0.15 mmol/L IPTG诱导,5 h后融合蛋白σC表达量可达高峰,分子质量为50ku;融合蛋白纯化后被用作包被抗原,建立了检测鸭血清中呼肠孤病毒抗体的间接ELISA,经对检测条件优化,最佳包被浓度为5μg/mL,标准阳性血清的最适稀释倍数为1∶40。用该方法对50份鸭血清样品进行了检测,与琼脂扩散抗体检测法相比,ELISA具有良好的特异性和敏感性。  相似文献   

9.
采用RT-PCR方法从鸭源呼肠孤病毒DRV-GZ株中扩增出了S2基因片段,将其克隆到表达载体pET-28a( )中,测序验证后转化入表达宿主茵RosettaTM2(DE3)plysS,进行IPTG诱导表达.结果表明,重组菌可表达出相对分子质量约为50000的重组融合蛋白,在浓度为0.6 mmol/L的IPTG诱导4 h的情况下表达效果最好.表达的蛋白以包涵体的形式存在于菌体中.表达产物经Ni柱纯化后可得到纯度较高的目的蛋白.经Western-blot分析,所纯化的蛋白能与抗呼肠孤病毒DRV-GZ株阳性血清进行特异性的免疫印迹反应,证实表达的蛋白具有较好的反应原性.  相似文献   

10.
采用RT-PCR方法从呼肠孤病毒3型(Reo-3)中扩增S1基因的主要抗原片段SR,并将其克隆到原核表达载体pQE-31中诱导表达,融合蛋白SR-δ1纯化后被用作包被抗原,建立了检测呼肠孤病毒3型抗体的间接ELISA.对表达蛋白进行SDS-PAGE和Western-blot分析的结果表明,表达蛋白SR-δ1的分子质量约为32 ku,具有很好的抗原性.建立的ELISA与鼠痘病毒、仙台病毒、小鼠肝炎病毒、小鼠肺炎病毒均无交叉试验,具有良好的特异性、重复性和敏感性,与国家实验动物检测中心的ELISA检测试剂盒的符合率为98.7%,证实该方法可用于Reo-3抗体的检测.  相似文献   

11.
A heated debate over the rise of China has been going on unabated in the international community for nearly two decades. However, with the elapse of time, the initial divergence of views in the mainstream opinion has gradually diminished and the gap in China policy among nations has likewise narrowed down. Instead, reason and a realistic approach have eventually taken center stare.  相似文献   

12.
布什政府上台以来,始终未能阻止朝鲜拥核步伐.朝核试后,美对朝政策有了新的调整,六方会谈得以复会.但美朝双方受各自国家利益和政策目标的限制,在朝鲜半岛无核化问题上的尖锐分歧难以解决,朝核危机仍存在再度升级的可能.  相似文献   

13.
This article argues for the confirmation of Marxist philosophy as the ideology that guides international relations (IR) studies in China. Justification comes through the following points. According to Marxism, correct theoretical guidance serves as the prerequisite for correct practice. Marxist philosophy embodies, by nature, righteousness, in opposition to political hegemony. Accordingly, practice under its guidance represents fruitful revolutionary realism. Finally, advanced studies of international relations in this country cannot be separated from philosophical thinking. Using these arguments as background, this article specifically advocates materialism, patriotism, and service to the people as the corner-stone of China's IR theory building.  相似文献   

14.
The EU's strategy for Russia since the end of the cold war has to a large extent failed, and the direct consequences are the currently deadlocked EU-Russia relationship. There are three reasons for this: the EU and Russia's respective strength and status relative to each other have been changing since the beginning of this century; the EU's strategy towards Russia has been more fragmenting in recently years; and the American factor. The EU-Russia relations could continue to be in poor shape in the years to come, and it is very likely sometimes even further worsening. But the two sides would refrain from extreme measures and prevent their relations from sliding into real cold war.  相似文献   

15.

Citizens in democracies are expected to make better decisions if they understand policy tradeoffs. However, politicians rarely have incentives to communicate them; citizens are uncomfortable choosing among valued outcomes; and devising a common metric is difficult. It is not surprising that in the United States the environment provides relatively little cuing or priming of tradeoffs in television news. Russian citizens, on the other hand, face a media environment in which tradeoff cuing is intentionally suppressed by owners' agendas, yet viewers detect concealed tradeoffs even in the absence of tradeoff priming and viewpoint diversity. Analysis of discourse among ordinary Russians in 16 focus groups convened in four cities, differentiated by political reform and media market environments, showed that when watching news in which tradeoffs are thoroughly concealed, viewers challenge stories by offering a broad spectrum of uncued tradeoffs. Tradeoffs come from diverse policy domains and represent a range of cognitive strategies, some of which are considerably more abstract than others and link elements of their observations and assumptions (together with what they can extract from the stories) into complex reasoning outcomes.  相似文献   

16.
There may be more than one year to go before the 2008 U.S. presidential election, but the primary election of the two parties has already begun ahead of time. Both the Democratic and Republican candidates for the  相似文献   

17.
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   

18.
1. Introduction
On the morning of April 1st, 2001, a U.S. EP-3 surveillance aircraft was conducting an intelligence flight along the Chinese territorial border in the airspace south-east of China's Hainan Island. Two Chinese fighter jets intercepted the spy plane and followed its flight, as is considered ordinary international practice. For reasons unknown, the EP-3 airplane made a sudden maneuver and crashed into one of the Chinese planes. The Chinese plane dropped into the sea, the pilot missing. The U.S. spy plane was also severely damaged. It intruded into Chinese territorial space and landed on Hainan Island without official permission from the Chinese side. After landing, the spy plane and 24 crew on board were detained by the Chinese authorities. This air collision episode was the first of its kind in the China-U.S. relations and an urgent diplomatic crisis ensued.  相似文献   

19.
正Chapter I General Rules Article 1 The Chinese Association for International Understanding is a national non-governmental organization(NGO)in the People’s Republic of China.Article 2 The official name of the Association is"Zhong Guo Guo Ji Jiao Liu Xie Hui"in Chinese,or"Jiao Liu Xie Hui"for short.Its English translation is"Chinese Association for International Understanding",and abbreviated as"CAFIU".  相似文献   

20.
Guide to Authors     
《中国国际问题研究》2014,(1):I0002-I0002
正Published by China Institute of International Studies,China International Studies is China’s first English-language journal on diplomacy and international politics for formal circulation.The magazine mainly publishes the latest research achievements of Chinese scholars and specialists on China’s diplomacy,international politics and international relations under such columns as China’s Diplomacy,International Relations,International Politics,International Security,Regional Issues and World Economy.  相似文献   

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