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1.
在广东省水禽养殖较密集的肇庆地区选择4个鸭疫里氏杆菌病发病鸭场和1个未发病鸭场,采集病料,进行病原分离,并用玻片凝集试验和琼脂扩散试验检测分离株的血清型.结果表明,该地区流行的鸭疫里氏杆菌(RA)仍以1型为主,但有1株与RA 1型抗血清无交叉反应.对RA分离株进行8种抗生素的敏感性试验显示,分离株对丁胺卡那霉素极度敏感,对头孢唑啉、新霉素、头孢氨苄高度敏感,对氯霉素、卡那霉素、庆大霉素、恩诺沙星有不同程度的抗药性.  相似文献   

2.
从河北省某肉鸭场的鸭疫里氏杆菌病发病鸭中分离出鸭疫里氏杆菌 (Riemerellaa natipestifer ,RA)菌株。对该菌株采用液体、固体两种方法增菌培养后制成油乳剂灭活疫苗 ,以 0 .5mL/只剂量经皮下免疫 7日龄雏鸭 ,并在河北省某发病肉鸭场进行了田间试验 ,表明该疫苗免疫效果良好 ,保护率达 90 %以上  相似文献   

3.
20 0 1年 6月至 2 0 0 2年 4月 ,从浙江省 7个地、市患典型鸭疫里氏杆菌病的不同品种病死鸭分离到 2 0株鸭疫里氏杆菌 (RA) ,所分离菌株对各品种雏鸭具有很强的致病性 ,各分离菌株表现出一致的形态特征和非常相似的生理生化特性。  相似文献   

4.
从疑似患有鸭疫里氏杆菌病的病死雏鹅分离病原菌并对分离到的菌株进行了形态学观察、生化试验、血清型鉴定、PCR鉴定、药敏试验及16SrRNA基因序列分析。结果显示,2个分离菌株为Ⅰ型鸭疫里氏杆菌;它们均对22种常用抗生素表现出耐药。这2株鹅源分离株与鸭源鸭疫里氏杆菌处于同一进化支上,与同属rRNA总科Ⅴ的伯杰氏菌属、金黄杆菌属、黄杆菌属的进化关系较近,与大肠杆菌、沙门菌、多杀性巴氏杆菌的进化关系较远。  相似文献   

5.
本研究旨在通过建立鸭疫里氏杆菌脉冲场凝胶电泳(PFGE)指纹图谱数据库,探讨不同来源的鸭疫里氏杆菌的流行病学及传播特征。2013年2月到2015年7月,从广东省9个城市收集具有典型鸭疫里氏杆菌病症状的病(死)鸭和鹅的脑、肝组织样品,分离培养鸭疫里氏杆菌。采用全自动微生物鉴定仪鉴定疑似菌株,并进一步用特异性PCR进行鉴定。对分离得到的菌株进行SmaⅠ-PFGE分子分型。结果显示,共分离得到115株鸭疫里氏杆菌,其中鸭源54株,鹅源61株。其中,58株菌株分型成功,得到16种不同的SmaⅠ-PFGE型(以相似度≥90%为判定标准),包括11个簇(Cluster)和5个单一型(Single type)。上述研究结果表明,分离得到的鸭疫里氏杆菌存在广泛的克隆传播,且存在于不同种属的宿主动物(鸭和鹅)之中。  相似文献   

6.
为了解重庆西部地区养鸭场鸭疫里氏杆菌血清型的分布及耐药谱,对送检的病死鸭进行了细菌学及病毒学分离鉴定;以参考菌株RA1和RA2制备血清,用玻片凝集试验及琼脂扩散试验鉴别疑似菌株的血清型;采取纸片法进行疑似菌株的药敏试验。结果显示,分离出2株血清型为1型的鸭疫里氏杆菌,分别被命名为YM1和YM2。它们对雏鸭的致病力较强,致死率分别达60%和70%;对头孢类药物、氨基糖苷类及黏杆菌素高度敏感,对四环素类、喹诺酮类、青霉素耐药。上述结果为当地鸭疫里氏杆菌病的防制提供了科学依据。  相似文献   

7.
从广西部分地区9个发病鸭场的病料中分离出9株疑似鸭疫里氏杆菌,经培养特性、形态、染色特性及生化反应特性等鉴定为鸭疫里氏杆菌(RA).RA血清型分型试验结果表明,9株分离菌中有7株(GX1、GX2、GX3、GX4、GX5、GX6、GX8)属血清型Ⅰ型;另2株(GX7、GX9)与GX1株的阳性血清无交叉凝集反应,GX7、GX9株制备的阳性血清也无交叉凝集反应,表明这2株菌既非Ⅰ型又不属同型的RA.经致病性试验,GX1株具很强的致病力,能使北京鸭和本地麻鸭发病死亡;GX7和GX9株仅能使北京鸭发病死亡,而不致本地麻鸭发病.结果表明,广西存在着不同血清型的RA,而且有的菌株致病性很强.  相似文献   

8.
将鸭疫里氏杆菌CH3株作为免疫原免疫BALB/c小鼠,细胞融合后将CH3株脂多糖(LPS)作为包被抗原,筛选阳性杂交瘤细胞株。共获得2株稳定分泌鸭疫里氏杆菌CH3株LPS单克隆抗体的杂交瘤细胞株,分别将其命名为7H1和8A9。2株单克隆抗体均为IgG1亚类。腹水单克隆抗体ELISA效价分别为1∶12 800和1∶6 400。玻片凝集试验和悬浮荧光试验检测结果表明,2株单克隆抗体与血清1型菌株WJ4发生特异性反应,而与鸭疫里氏杆菌血清2型菌株NJ-3及血清10型菌株HXb2无反应性。Westernblot结果表明,2株单克隆抗体与LPS的反应条带位于LPS O抗原部分。本研究成功制备了稳定性好、特异性强的LPS单克隆抗体,可用于进一步研究鸭疫里氏杆菌LPS的结构和致病机制。  相似文献   

9.
1994年 1月至 2 0 0 0年 10月 ,从全国 2 5个省、自治区、直辖市的 5~ 90日龄患典型鸭疫里氏杆菌病的种鸭和商品鸭中分离到 89株血清 5型鸭疫里氏杆菌。对其病原学特性研究结果表明 ,血清 5型鸭疫里氏杆菌病在我国鸭群感染范围极广 ;分离菌株对雏鸭具有很强的致病性 ,对小白鼠无致病性 ;各地分离菌株表现出一致的形态特征和非常相似的生理生化特性 ;各地分离菌株耐药谱很广 ,但对头孢类药物和利福平高度敏感。用分离菌株制备的灭活疫苗免疫雏鸭具有很好的免疫原性。  相似文献   

10.
为研究鸭疫里氏杆菌耐药表型与耐药基因的关系,从浙江某鸭场病鸭体内分离到1株病原菌,经菌落形态和革兰染色特性观察、生化鉴定、PCR鉴定、动物回归试验,确定其为鸭疫里氏杆菌强毒株,血清凝集试验表明其为血清11型;药物敏感性分析结果显示,该菌对多黏菌素、复方新诺明、庆大霉素、四环素等耐药,对氨苄西林、头孢拉定、头孢唑林等敏感,属于多重耐药菌株;通过基因组高通量测序分析,检测到与表型相关的多黏菌素、红霉素、四环素等相关耐药基因,同时检测到多药外排泵及多药耐药蛋白基因,耐药表型与耐药基因检测结果相符。结果表明,通过高通量测序技术能准确获得鸭疫里氏杆菌分离株抗生素耐药的相关基因信息,对鸭疫里氏杆菌病的临床用药具有一定指导意义。  相似文献   

11.
Britain's entry into the European Community in 1973 coincided with an American initiative aimed at redefining relations between the United States and Western Europe. This confronted British diplomats with a serious dilemma. They wished to maintain close collaboration with Washington and, for the sake of European unity, to expand on their recently achieved reconciliation with France, a country whose Gaullist elite rejected any further institutionalization of transatlantic relations. French reluctance to engage in a constructive dialogue with the Americans resulted in a fractious debate over the drafting of two seemingly innocuous declarations, and this was exacerbated by the mixed response of the Europeans to the outbreak of the fourth Arab–Israeli war and the ensuing energy crisis. Finally, at the Washington energy conference of February 1974, the British chose to work with the Americans, rather than the French, in seeking to mitigate the economic impact of OPEC's oil policies.  相似文献   

12.
《Diplomacy & Statecraft》2006,17(4):871-895
Britain's entry into the European Community in 1973 coincided with an American initiative aimed at redefining relations between the United States and Western Europe. This confronted British diplomats with a serious dilemma. They wished to maintain close collaboration with Washington and, for the sake of European unity, to expand on their recently achieved reconciliation with France, a country whose Gaullist elite rejected any further institutionalization of transatlantic relations. French reluctance to engage in a constructive dialogue with the Americans resulted in a fractious debate over the drafting of two seemingly innocuous declarations, and this was exacerbated by the mixed response of the Europeans to the outbreak of the fourth Arab-Israeli war and the ensuing energy crisis. Finally, at the Washington energy conference of February 1974, the British chose to work with the Americans, rather than the French, in seeking to mitigate the economic impact of OPEC's oil policies.  相似文献   

13.
This article reports on exploratory research based on interviews with expatriate and local aid workers employed by local and international NGOs in Phnom Penh, Cambodia. Thematic analysis of the interviews found that personnel were placed in groups based on their job category – consultant, volunteer, or permanent staff – regardless of experience. These categories logically reflect each worker's pay level, purpose, and role, but they may also have an implicit power meaning which reinforces group differences and inhibits inter-group relationships. Relationship building was reported to be the most important factor contributing to the success of capacity-development initiatives. Four sub-themes were identified: communication, friendship, reciprocal learning/teaching, and confidence.  相似文献   

14.
"印太战略"是美国均势+有限遏制+规制+话语诋毁的混合型战略。它意在前沿、中间地带与后方的三层构建不对称的对华遏制性力量,突破中美双边、单区域战略竞争的狭窄战略空间;在多地域与多维度孤立中国,拉拢更多国家在产业价值链、数字经济等层面与中国切割;制订基础建设投资透明化的新标准,嵌入有利于美国利益的规制;通过国际法、舆论等软性手段抹黑中国的"一带一路"与海权发展。虽然共同逻辑都是制衡中国崛起,但日澳印在策略上强调非对抗性。其中避免成为中国优先反制是日本重要的策略目标;印度在拉达克边界冲突后尚没有形成一个完全倒向美国的战略,因为这必定使其背上沉重的战略包袱,成为美国的附庸;澳大利亚作为地缘政治影响有限的中等国家,在美国反华行动中冲在最前列已使其利益严重受损。而"印太战略"与东盟所推动的包容性、合作安全理念也有着本质的区别,东盟要在"印太地区"发挥中心领导作用,定位"印太"为对话与合作区域。所以由于东盟的抵制、印日澳的消极政策,这个战略形成的攻势将很难保持可持续性,其长期前景并不看好。  相似文献   

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《国际相互影响》2012,38(4):365-389
In this paper, we suggest that the Investment Model of Commitment, developed in social psychology, offers a solution to an important microfoundational issue in audience cost theory. Audience cost models are useful for thinking about the foreign policy behaviors of democratic and nondemocratic states. However, they often assume that citizens reliably penalize leaders who break their foreign policy promises even though the empirical record suggests this is not always the case. We argue that public commitment to foreign policy assets and relationships is a precondition for the application of audience costs. Using the UN and NATO as case studies, we hypothesize that the commitments people develop to international organizations emerge as a function of (1) their satisfaction with the performance of the organization, (2) the investments in those organizations, and (3) an assessment of the alternatives to these associations. Correlational and experimental tests of the model confirm that the strongest individual-level commitments arise when people are highly satisfied with the performance of specific institutions, believe that much has been invested in support of them, and perceive that the alternatives to particular institutions are poor. Implications for the development of audience cost theory are discussed.  相似文献   

20.
Please click here to view a statement of retraction concerning this article.  相似文献   

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