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为探讨鸭甲肝病毒(DHAV)GX株基因分型特点及主要衣壳蛋白(VP1)的生物学特性,本试验对其进行全基因组序列测定,并应用分子生物学软件将DHAV GX株与DHAV 3个血清型参考毒株进行序列比对分析。结果显示,其基因组全长7 800 bp,由5'和3'非编码区(UTR)和一个大开放阅读框(ORF)组成。其中,5'UTR和3'UTR的长度分别为652和369 bp;ORF长度为6 756 bp,编码2 251个氨基酸长的多聚蛋白,其编码产物至少有12个(VP0/VP3/VP1/2A1/2A2/2A3/2B/2C/3A/3B/3C/3D);在分类地位上DHAV GX株属于DHAV-3,其与DHAV-3参考株核苷酸、氨基酸同源性最高;与DHAV-3 FS株亲缘关系最近,在同一较小分支上。DHAV GX株结构蛋白VP1以第195—201、211—221位氨基酸区段为B细胞优势表位的可能性较大。提示,VP1基因可作为研制DHAV基因工程疫苗的优势候选基因。 相似文献
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采用RT-PCR法对Ⅰ型DHV A66弱毒株基因组全序列进行了分子克隆与测序.研究结果表明,不含Poly(A)尾巴的A66株的基因组全长为7 704个核苷酸残基,包括626个核苷酸残基的5′端非编码区、6 750个核苷酸残基的开放阅读框和314个核苷酸残基的3′非编码区.应用分子生物学软件将A66株与GenBank公布的其他DHV-Ⅰ全基因序列进行同源性比较分析,结果表明,除了90D和04G两株变异株外,A66株ORF的核苷酸序列与其他各株的同源性在94.3%～99.7%之间,氨基酸序列的同源性在97.3%～99.6%之间,并且A66与C80、JX弱毒株的核苷酸和氨基酸序列的同源性均很高,在99.4%以上,各毒株氨基酸序列同源性比核苷酸同源性略高.Ⅰ型DHV病毒基因组的一级结构高度保守. 相似文献
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为了给在分子水平上研究鸭肝炎病毒(DHV)的致病机理奠定基础,进一步丰富DHV的遗传变异和进化信息,试验采用RT-PCR方法分段克隆获得DHV-1 GD株的全基因组序列并进行序列分析。结果表明:GD株的基因组全长7 690 nt[不含Poly(A)尾],5’端和3’端非编码区长度分别为626 nt和314 nt,单一开放阅读框架(ORF)为627～7 376 nt,编码2 249个氨基酸;GD株与DHV-1参考株比较,其核苷酸和氨基酸同源性分别为94.8%～99.7%和97.7%～99.6%;与中国台湾和韩国新型DHV(DHV-N)相比同源性分别为72.7%～73.2%和81.8%～83.4%;GD株与DHV-1参考株遗传进化关系较密切,处于同一分支,而与DHV-N遗传关系较远,处于不同分支。 相似文献
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为研究牛病毒性腹泻病毒(BVDV)的分子特征,本研究参考GenBank中登录的BVDV基因Ⅱ型病毒株全基因组序列,设计多对引物,通过RT-PCR方法,对一株分离自某商品化血清中的BVDV分离株HLJ-10全基因组进行分段克隆及序列测定,获得了该分离株的全基因组序列。生物信息学分析表明,该分离株为BVDV基因Ⅱ型,全长12 284 nt,编码区为11 694 nt,共编码3 897个氨基酸,5’和3’非编码区分别为385 nt和205 nt。与其它BVDV参考株序列比对分析表明,HLJ-10与SH-28和KZ91CP进化关系较密切,预测该分离株含有22个潜在糖基化位点,氨基酸差异性分析表明E2蛋白的氨基酸序列在瘟病毒属中变异性较大。 相似文献
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对我国鸭病毒性肝炎病毒(Duck hepatitis virus,DHV)分离株JFX08的全基因组进行了序列测定与分析。结果表明,JFX08毒株的基因组全长为7793nt,包括652nt的5’UTR,6753nt的ORF,366nt的3’UTR以及19nt的poly(A)尾巴。JFX08毒株的ORF编码2251个氨基酸,各基因均与韩国新型毒株的氨基酸序列相似性最高,与1型DHV和台湾新型DHV的序列相似性均较低。其中VP1较1型DHV存在2个氨基酸的插入和较多氨基酸位点的突变,高变区主要集中在180～194位和213～219位。JFX08毒株的非编码区核苷酸序列之间存在大量碱基突变和插入/缺失。多聚蛋白、VP0、VP3、VP1、2C和3D基因进化分析结果均表明,JFX08分离株与韩国新型DHV的遗传距离最近,属基因C型。 相似文献
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采用RT-PCR和RACE技术,从鹿茸软骨细胞总RNA中扩增克隆了梅花鹿X型胶原（collagen X,colX）全长cDNA序列,并进行了序列特性分析。序列分析结果表明,梅花鹿colX全长cDNA序列为3135nt,其中5′非编码区96nt、3′非编码区1014nt和2022nt的开放阅读框编码674个氨基酸的鹿colX前体蛋白,与牛、猪、犬、人类和小鼠等脊椎动物colX氨基酸序列之间的同源性超过82%。按该基因氨基酸序列构建了进化树,揭示其与牛基因更加同源。 相似文献
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猪圆环病毒2型广西株的分离和全基因组序列分析 总被引：1，自引：1，他引：0
从广西表现为断奶仔猪多系统衰竭综合征的猪群中分离到1株猪圆环病毒2型(PCV-2),命名为GXB株.对GXB株的全基因组进行PCR扩增,扩增产物克隆至PMD18-T载体.测序结果表明,全基因组为1 767 bp,与GenBank上已知的8株PCV-2参考株序列的同源性在95.0%～99.6%之间.序列分析表明,GXB株基因组包含11个读码框(ORF),其中ORF1和ORF2是最主要的读码框,分别编码314个和233个氨基酸,与其他PCV-2毒株的ORF1、ORF2氨基酸的同源性分别为97.8%～100%、91.5%～98.7%.对GXB株ORF2编码的Cap蛋白基因进行功能分析,表明含有1个潜在的糖基化位点,3个明显的亲水区,有较强的抗原性和亲水性,为作为主要的免疫原性蛋白基因提供了依据. 相似文献
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《黑龙江畜牧兽医》2017,(11)
为了研究猪戊型肝炎病毒(Hepatitis E virus,HEV)黑龙江分离株SWHLJ-BXBX的全基因组序列,并对其序列特征和进化关系进行分析,试验采用RT-n PCR、5'-RACE、3'-RACE方法和Megalign、MEGA 6等生物学软件对SWHLJ-BXBX的全基因组序列进行了研究。结果表明:SWHLJ-BXBX全基因组序列去除poly A后全长为7 240 bp,5'UTR有25个碱基,3'UTR全长为70 bp,ORF1编码1 707个氨基酸,ORF2编码674个氨基酸,ORF3编码114个氨基酸,进化树分析表明SWHLJBXBX属于HEVⅣd基因亚型。 相似文献
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本研究从上海市某鸭场发病鸭群中分离到1株DHV-1型强毒株,对其进行毒价测定、琼脂扩散试验和动物回归实验,结果显示：按103.41 ELD50/0.2 mL接种1日龄雏鸭,该毒株对雏鸭有明显的致病性,死亡率为60%,肝脏病变率为100%。经全基因组测序显示：该毒株长度为7652 nt,含626 nt的5＇非编码区和314 nt的3＇非编码区,编码一个2249 aa大小的多聚蛋白。根据Blast比对发现,该毒株属于经典的DHV-1A群,与韩国经典强毒株R85952（99.7%）和中国分离强毒株HP-1（99.3%）的同源性最高。 相似文献
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参考GenBank上已发表的口蹄疫病毒（FMDV）全长基因组序列,设计了覆盖基因组全长的数对引物,通过RT-PCR方法对1株Asia1型（简称As01）FMDV进行分段克隆及序列测定,将测序结果利用软件进行拼接。结果表明,该毒株的FMDV基因组[不合poly（C）]全长8180nt,其中编码区为6987nt,5’和3’非编码区（UTR）分别为1078nt和95nt,3＇UTR之后为20nt的poly（A）尾巴。将As01株与其他FMDV参考毒株利用分子生物学软件进行多序列比对分析表明,As01株与Asia 1／Jiangsu／China／2005、Asia 1／Isr 1／3／63、ZB／CHA／58等Asia 1型FMDV遗传进化关系较为密切,而与O型和A型FMDV遗传关系较远。 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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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 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