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1.
禽呼肠孤病毒(avian reovirus,ARV)属于呼肠孤病毒科(Reoviridae)正呼肠孤病毒属(Orthoreovirus)。ARV病毒粒子为无囊膜的20面体,双层衣壳,直径60-80nm,氯化铯浮密度为1.36~1.37g/mL。基因组为10个节段的双股RNA,根据核酸电泳迁移率的不同,可以分成3组:3个大基因节段(L1、L2、L3),3个中基因节段(M1、M2、M3),4个小基因节段(S1、S2、S3、S4)。编码的蛋白至少有14种,  相似文献   

2.
蓝舌病病毒(bluetongue disease virus,BTV)是呼肠孤病毒科环状病毒属的双股RNA病毒,其核酸由3个大片段(L1~L3)、3个中片段(M4~M6)和4个小片段(S7~S10)等10个节段组成,分别编码7种结构多肽(VP1~VP7)和4种非结构多肽(NS1、NS2、NS3a、NS3b)。通过dsRNA基因组进行体外翻译,再根据各基因与所编码蛋白的关系,查明了各基因编码的蛋白质及其分子质量和功能。  相似文献   

3.
本研究自广东省新兴地区疑似新型鸭呼肠孤病料样品中分离出一株病毒,命名为DRV-XX株。利用RT-PCR方法对DRV-XX株进行全基因组序列扩增,拼接获得其全基因组(23 419 bp),对其10个基因节段进行分析显示,该分离株与禽呼肠孤病毒(ARV)及番鸭呼肠孤病毒(MDRV)的相似性较低,而与国内新型鸭呼肠孤病毒(New-type duck reovirus,NDRV)相似性较高(99%),表明该分离株为NDRV。对其10个RNA节段分别进行测序及遗传进化分析,其中S3基因序列分析显示,DRV-XX与MDRV共同构成一主干支,与其S1、S2、S4、M1、M3、L1基因的一致;而M2基因进化树显示,DRV-XX与ARV处于同一主干支;由L2、L3组基因分析显示,DRV-XX与ARV在同一主干支,并有MDRV参与其中,而另一主干支为MDRV。因此,推测DRV-XX株的不同基因组节段来源不同,可能是ARV和MDRV发生同义突变,也可能是基因重组的结果。该研究丰富了NDRV的基因库相关信息,也为广东地区NDRV的防制提供一定参考依据。  相似文献   

4.
呼肠孤病毒广泛的宿主性以及自身基因组的结构特征使其在进化过程中呈现遗传多样性,新型禽源呼肠孤病毒在此过程中不断出现,引起家禽和水禽养殖业的严重经济损失。其中,关于S1基因节段的科学研究对于理解病毒致病性改变以及疫苗开发有关键作用。因此,本文拟就禽源呼肠孤病毒的发生、S1基因的结构及其编码的非结构蛋白P10、P17和结构蛋白σC的生物学功能最新研究进展作一概述。  相似文献   

5.
禽呼肠病毒是正呼肠病毒属的重要成员之一,能感染禽类,直接危害肉鸡、蛋鸡、幼龄火鸡和雏番鸭的生长发育,甚至引起死亡,从而导致严重的经济损失。近年来,人们对禽呼肠病毒分子生物学方面的研究已有不少进展,特别是关于禽呼肠病毒的S1基因编码蛋白的机制。禽呼肠病毒的基因组含有10个双链RNA基因片段,其中的9个基因片段均是以核糖体扫描翻译机制来合成对应的病毒蛋白。但S1基因片段的结构较为特殊,其RNA基因片段含有3个相互重叠的基因编码区,并利用不同的翻译机制分别合成3种蛋白,即非结构蛋白p10、p17和结构蛋白σC。这3种蛋白的主要作用分别是引起病毒感染的细胞与周围正常细胞之间的融合,促进病毒在细胞内的繁殖,帮助病毒吸附易感细胞表面的受体等。论文着重介绍禽呼肠病毒S1基因编码蛋白的相关合成机制。  相似文献   

6.
参考GenBank中禽呼肠孤病毒S3基因序列设计一对引物,以禽呼肠孤病毒内蒙古分离株(C-98)基因组RNA为模板,应用RT-PCR方法获得病毒的S3基因,并克隆到pMD19-T载体后测序。应用计算机软件将所测定序列与参考毒株ARV 176、ARV S1133、ARV 138的S3基因序列进行比较,核苷酸同源性分别为99.8%,99.6%,87.7%,推导其氨基酸同源性分别为99.5%,98.9%,94.8%。应用PHD程序和DNAStar软件,对S3基因所编码的σB蛋白结构进行预测,结果表明,σB蛋白为结构紧密的球状蛋白分子。  相似文献   

7.
为研究鹅源新型鸭呼肠孤病毒的全基因组分子特征及其广西流行株的进化特点,本研究采集广西地区3份发病鹅的肝脏、脾脏、肺脏及肾脏病料样品,采用多重荧光定量RT-PCR (RT-qPCR)检测番鸭呼肠孤病毒(MDRV)和新型鸭呼肠孤病毒(NDRV),并以NDRV阳性样品的核酸为模板,采用RT-PCR分段扩增其全基因组并测序,采用BioEdit软件分析其全基因组序列的相似性;采用NetNGlyc 1.0软件预测NDRVσC蛋白N-糖基化位点;通过Mega 7.0软件绘制σ系列基因的系统发育树及RDP5和SimPlot软件分析NDRV全基因组的重组事件。RT-q PCR结果显示,检出1份NDRV阳性样品,经测序及序列拼接,获得一条鹅源NDRV广西流行株G-NDRV-GX-2022全基因组序列,全长23 353 bp,分为L1~L3、M1~M3及S1~S4共10个基因;BlAST分析结果显示,G-NDRV-GX-2022株10个基因与GenBank中相应基因序列的相似性最高为91.2%~98.4%,对应的病毒株均源自中国广东、福建、山东、浙江及湖北等地的NDRV,宿主有野鸭、番鸭、绿头鸭等,表明G-...  相似文献   

8.
旨在研究肉鸡呼肠孤病毒分离株致病与基因组变异情况。2017年从山东潍坊地区跗关节肿胀、出血严重商品肉鸡中收集病料,进行病毒分离,通过RT-PCR检测、电镜观察对病毒进行鉴定;将分离到的病毒回归商品肉鸡;设计18对引物对分离株全基因组扩增测序,并进行了遗传进化分析;将分离毒株与经典毒株S1133进行血清交叉中和试验。结果表明分离到一株禽呼肠孤病毒(命名为WF17),回归商品肉鸡能完全复制出临床症状,并能从试验鸡中重新分离到该病毒。该分离株基因组完全符合禽呼肠孤病毒基因组结构特点,主要抗原σC蛋白基因与台湾918株最接近,相似性为92.7%,与S1133株的相似性只有55.9%。WF17株与S1133株的抗原相关指数(R值)只有0.19。目前以S1133株为主的商品化疫苗无法对禽呼肠孤病毒变异株产生有效保护。  相似文献   

9.
番鸭呼肠孤病毒非结构基因的克隆和序列分析   总被引:8,自引:1,他引:8  
参考GenBank禽呼肠孤病毒(Avian Reovirus,ARV)和番鸭呼肠孤病毒(Muscovy Duck Reovirus,MDRV)非结构基因(NS)序列设计合成一对引物,对番鸭呼肠孤病毒S14和C4株NS基因进行RT-PCR扩增,克隆到pMD18-T载体中,并对克隆产物进行酶切鉴定和测序;番鸭呼肠孤病毒NS基因由1 291 bp核苷酸组成,与禽呼肠孤病毒NS基因相比,在非编码区第1155位少一个碱基,本文第一次证实1291bp是番鸭呼肠孤病毒NS基因特有的长度;番鸭呼肠孤病毒S14和C4株NS基因的5'末端和3'末端分别为5‘GCTTTT和TCATC-3',是禽类呼肠孤病毒基因末端特有的碱基序列,S14和C4株NS基因的的有效阅读框(24~1127bp)编码367个氨基酸组成的蛋白,分子量约为40kDa;番鸭呼肠孤病毒S14和C4株NS蛋白等电点分别是7.3和7.0,GC含量分别为54.26%和53.71%,番鸭呼肠孤病毒S14和C4株NS基因间核苷酸同源性为99.3%,仅有4个氨基酸差异,S14和C4与法国番鸭呼肠孤病毒89026株NS基因核苷酸同源性分别为87.8%和87.9%,与鸡关节炎病毒S1133 NS基因同源性分别为79.0%和79.3%;进化树分析表明本研究中的两株番鸭呼肠孤病毒非结构基因(NS)与番鸭呼肠孤病毒的亲缘关系比禽呼肠孤病毒近的多,建议番鸭呼肠孤病毒应归属为正呼肠孤病毒属第二个亚群中不同于禽和内尔森贝海湾呼肠病毒独立基因群.  相似文献   

10.
中国禽(番鸭)呼肠孤病毒YB株S4基因序列分析   总被引:5,自引:0,他引:5  
应用非免疫番鸭胚增殖中国禽(番鸭)呼肠孤病毒YB分离株,用LSTRIAZOL提取病毒RNA,反转录-聚合酶链反应(RT-PCR)扩增中国禽(番鸭)呼肠孤病毒YB分离株S4基因节段cDNA.将S4cDNA克隆到PMDl8-T载体上,并进行了鉴定和核苷酸序列测定.序列分析结果,克隆的S4cDNA共1 124bp,包括非编码区和完整的阅读框架.分子进化系统分析表明该毒株与禽呼肠孤病毒(鸡呼肠孤病毒)的亲缘关系较远,DRV-YB与DRV-89330同缘率为93.3%.  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

18.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

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