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马传染性贫血病病毒(equine infctious anemiavirus EIAV)导致马持续性感染和反复病毒血症,与人免疫缺陷病毒Ⅰ型(HIV-1)同属反转录病毒科慢病毒属,二者有很多相似的特性[2].EIAV是遗传结构最简单的慢病毒,其感染的潜伏期只有几天至几周,而且在EIAV感染过程中新的抗原变异株的出现与疾病的反复发作相关,这使EIAV有可能作为研究HIV-1分子致病机理及免疫机制的动物模型[3]. 相似文献
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马传染性贫血病(EIA)是马属动物的一种由马传染性贫血病病毒(EIAV)所引起的传染病。关于 EIA 的特异性诊断及免疫性质等问题,各国学者曾从不同角度试图予以解决。但在研究本病的长期过程中,由于特异性血清学诊断未被突破,不能证明有抗体存在,并认为 EIAV 侵入马属动物后缺乏免疫学反应,从而导致了 EIA 的特异性诊断及免疫学研究迟迟不得进展。60年代初,小林报导了 EIAV 能在离体培养的马白细胞 相似文献
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马传染性贫血病毒(Equine infectious anemia virus,EIAV)长末端重复序列(Long terminal repeat,LTR)是基因组中高度变异区之一,EIAV LTR的变异对于指导病毒的复制和病毒致病性具有重要的生物学意义。为了阐明我国马传染性贫血病毒弱毒疫苗毒力致弱的分子机制,由马传贫强毒至弱毒致弱过程中不同代次毒株LTR序列的分析,以驴胎皮肤弱毒株疫苗全长感染性克隆pLGFD3-8为父本,选取LTR R区的TAR起始碱基,poly(A)附加位点,采用反向遗传操作对其位点进行PCR体外定点突变,将弱毒序列构建的逆向点突变型全基因克隆转染到驴胎皮肤细胞(FDD)并在FDD上传代,通过逆转录酶活性(RT)检测、RT-PCR方法及real-time RT PCR检测并验证其感染性。检测结果为构建的逆向点突变型感染性克隆在FDD上被拯救,其衍生病毒感染的FDD上出现明显的细胞病变;细胞培养上清可检测到RT酶活性和RT-PCR阳性;电镜下可见大量典型的EIAV颗粒pLGFD-M点突变型嵌合克隆衍生病毒与其父本克隆衍生病毒pLGFD3-8复制水平相似。此结果为进一步深入研究LTR对马传染性贫血病毒复制水平和毒力的影响奠定了基础。 相似文献
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马传染性贫血病毒(EIAV)属于逆转路病毒科满病毒亚科成员之一,它可在马体内建立持续感染,其特点是反复出现病毒血症为特征的一系列表现,由于病毒独特,临床症状复杂, 相似文献
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马传染性贫血病毒(Equine infectious anemia virus,EIAV)属于逆转录病毒科慢病毒属,由该病毒引起的马传染性贫血(简称马传贫或EIA)是马属动物的一种非常重要的传染 相似文献
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马传染性贫血(equine infectious anemia)简称马传贫(EIA),是由反录病毒科慢病毒属马传染性贫血病毒引起的马、骡、驴传染病。其特征主要为间歇性发烧、消瘦、进行性衰弱、贫血、出血和浮肿,在无烧期间则症状逐渐减轻或暂时消失现几乎遍及全世界,对养马业造成巨大经济损失。 相似文献
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马传染性贫血病毒(Equine infectious anemia virus,EIAV)是逆转录病毒科慢病毒属的成员之一,其基因组结构与人免疫缺陷病毒Ⅰ型(Human innunodeficiency virus type 1,HIV-Ⅰ)相似。马传染性贫血呈世界性分布,常引起慢性感染,以发热、贫血为特征,耐过马呈隐性感染并终身带毒。20世纪70年代初期,Coggins博士建立了检测感染马血清抗体的琼脂扩散试验(AGID),成为检测EIA的标准方法。 相似文献
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《中国预防兽医学报》2020,(7)
正马传染性贫血病毒(EIAV)属反转录病毒科慢病毒属成员,主要感染马、驴和骡等马属动物。其引起马属动物呈现发热、贫血、出血、黄疸、消瘦、水肿和心脏衰弱等一系列症状的传染性疾病称为马传染性贫血(EIA),简称为马传贫。EIAV与人类免疫缺陷病毒(HIV-1)和猴免疫缺陷病毒(SIV)等慢病毒属成员在病毒基因组结构、复制分子机制、免疫机理及与宿主相互作用等方面都具有相似性。因此,EIAV被认为是研究慢病毒致病机制的重要模型病毒。马传染性贫血病毒弱毒疫苗作为世界上首例成 相似文献
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马传染性贫血病驴白细胞弱毒株的致弱及免疫机理的研究 总被引:6,自引:0,他引:6
马传染性贫血病 (EIA)是由反转录病毒科慢病毒属的马传染性贫血病毒 (EIAV)引起的一种马属动物传染病。在慢病毒属中 ,EIAV与人免疫缺陷病毒 (HIV)在传播形式 ,单核细胞为病毒贮存库 ,病毒形态结构 ,病毒持续感染 ,病毒抗原漂移 ,EIAV的 P2 6与 HIV的 P2 4之间抗原交叉反应等都更为相似。至今 ,我国马传染性贫血病驴白细胞弱毒疫苗 (DL V)是目前世界上唯一成功应用的慢病毒疫苗 ,是慢病毒免疫预防很有希望的研究模型。因此 ,揭开 DL V的致弱及免疫机制 ,这使 EIAV有可能作为研究 HIV等慢病毒的致病机理及免疫机制的模型。EI… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献