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1.
牛传染性鼻气管炎病毒TK基因缺失株的构建   总被引:8,自引:1,他引:7  
将含有牛传染性鼻气管炎病毒( I B R V) T K 基因的片段克隆于p Bluescript S K 中, 再用 Bg1 Ⅱ和 Sac I切去 T K 基因中347bp 的片段, 获得了含缺失 T K 基因的重组质粒, 然后插入 Lac Z 报告基因, 构建成转移载体。以脂质体转染法将此转移载体与 I B R V Bartha 株在牛肾细胞( M D B K) 上共转染, 经过蓝色蚀斑筛选和蚀斑克隆纯化, 获得了能稳定遗传的重组 I B R V。经 P C R 和 Southern 印迹杂交鉴定, 证实该重组病毒为 T K 基因缺失突变株。  相似文献   

2.
鸡痘病毒282E4弱毒株TK基因限制性酶切图谱分析   总被引:2,自引:1,他引:1  
以限制性内切酶BamHI、Xbal、Clal、H1ndⅢ、Ncal对含有鸡痘病毒(FPV)282E4弱毒株3.7kbHindⅢTK基因片段的重组质粒pSL1进行单酶和它们之间双酶酶切。结果表明:3.7kbHindⅢTK基因片段上有2个Clal切点,2个Xbal切点,1个Ncal切点,没有BamHI切点。随后,用澳大利亚FPV2.2kbHindⅢ+ClalTK基因作探针,对各种酶切片段进行Southern印迹杂交,进一步确定TK基因位于2.2kbHindⅢ+Clal片段中。杂交结果与限制性酶切图谱分析结果相一致。该基因的限制性酶切图谱与澳大利亚FPV疫苗株的基本相同。  相似文献   

3.
从包含伪狂犬病病毒(PRV)闽A株BamHI-7片段的重组质粒pPR128中分离出含有完整糖蛋白gp50基因的2.1kbDNA片段,用KpnI和StuI酶切后,将其酶切片段分别克隆到pUC19载体中,构建了2.1kb片段完整测序用质粒。对其序列进行分析,发现与文献报道结果一致,证明分离的gp50基因是正确的。将包含gp50基因的2.1kb和1.6kbDNA片段分别插入带有痘苗病毒天坛株TK基因区段的pGJP-5质粒P7.5启动子的下游,构建了pGBT50-36和pGBT50-S22个嵌合载体。将嵌合载体通过磷酸钙共沉淀法转染预先感染TK+痘苗病毒天坛株的人TK-143细胞或CV-1细胞,进行体内同源重组。经蚀斑纯化,在BdUR选择压力下,通过光敏生物素标记的探针杂交,获得带有PRVgp50基因的重组痘苗病毒。用ELISA检测,重组痘苗病毒有特异性PRVgp50抗原存在。  相似文献   

4.
利用限制性内切酶从 TspⅡpuc19质粒上切取含 E S抗原的基因片段 TspⅡ,插入到含有 S P6 启动子和 S V40启动子的表达载体 P S VsportⅠ中,从而构建了 E S抗原( TspⅡ)的表达质粒。  相似文献   

5.
猪繁殖和呼吸综合征病毒(PRRSV)的基质膜(M)蛋白和核衣壳(N)蛋白是2种重要的结构蛋白。本试验根据PRRSV美洲毒株的基因序列,设计了能够扩增M和N蛋白基因的1对引物,并在2个引物的两端分别加入EcoRI和BamHI酶切位点,经RT-PCR技术获得了一约950bp的目的基因片段,并将此基因克隆于PBV220载体,构建了MN蛋白基因重组质粒PBVMN,进一步由重组质粒回收MN基因片段亚克隆于pSK+(pBluescriptSK+)测序载体,构建了重组质粒PBSMN,经部分序列分析鉴定,重组质粒含MN蛋白基因。此基因的克隆为进一步研究该病毒MN蛋白免疫学特性及其分子基础和基因诊断技术奠定了基础。  相似文献   

6.
鸡痘病毒282E4株2.2kbTK基因序列分析   总被引:7,自引:2,他引:5  
将鸡痘病毒282E4弱毒株基因组中的3.7kbHindⅢ片段克隆到KS(-)质粒中,亚克隆后,获得含TK基因正反方向插入的2.2kbHindⅢ-ClaI片段的质粒pKFA和pKFB,进而构建出正反方向的系列嵌套缺失质粒。用T7、T3引物所做的核苷酸序列分析表明,2.2kbHindⅢ-ClaI TK基因序列长为2159bp,含有两个完整的读码框架(ORE)X和TK,并确证了TK基因内存在单一酶切点N  相似文献   

7.
狂犬病病毒糖蛋白基因在原核细胞中的表达   总被引:2,自引:0,他引:2  
将狂犬病病毒糖蛋白(RVgp)基因BglⅡ片段(1675bp)分别正向插入到原核高效表达载体pET-17b和pET-17b2(用SacⅠ-NdeⅠ缺失掉pET-17b60bp含起始密码子ATG小片段)的BamHⅠ切点,构建重组质粒pET-17bRVgp和pET-17b2RVgp。将其分别转化表达受体菌E.coliBL21(DE3)和E,coliBL21(DE3)plysS.IPTG诱导表达,菌体经超声波裂解处理后SDS-pAGE,染色,在分子量约60000处可见重组质粒表达的较宽的蛋白带,以抗RVgpMcAb进行Western-blot检测,表明该表达蛋白为RVgp。通过扫描显示,表达的RVgp占菌体总蛋白的10%~14%,其中pET-17b2RVgp在E。coliBL21(DE3)中的表达量最高。  相似文献   

8.
将新城疫病毒(NDV)F46E9株和LaSotaE4株的融合蛋白裂解位点(Fc)基因从本实验室构建的重组质粒pUCF46Fc和pUCLaFc中用EcoRI和SalI切出。将这2个毒株的Fc基因定向克隆入昆杆状病毒表达载体pSXIVVIX3的EcoRI和SalI位点之间,获得2个毒株的Fc基因克隆pX3F46Fc和pX3LaFc。重组质粒用EcoRI/SalI,PstI酶切法,PCR和核酸探针法进行  相似文献   

9.
以Xba I和Eco RV双酶消化pBT1获得肿瘤坏死因子α(TNFα)cDNA基因片段,以Xba I和Sma I酶切点定向克隆入质粒载体pCMV4,构建了人TNFα重组质粒pCMV-TNFα。采用DNA-磷酸钙共沉淀法转染COS7和NIH3T3细胞,收集转染后不同时间的细胞培养上清,检测TNFα的表达水平和生物学活性。ELISA检测表明,两种细胞转染后,其培养上清中均有TNFα抗原存在,而载体等  相似文献   

10.
将组织型纤溶酶原激活剂(t-PA)基因cDNA经多次亚克隆插入到真核表达载体pSVL的SV40启动子和pcDNA3的CMV启动子下游,构建了重组表达质粒pSVL-tPA和pcDNA3-tPA。分别将这2种表达质粒以脂质体载体法转染BHK21细胞,ELISA检测结果表明,pSVL-tPA和pcDNA3-tPA在哺乳动物细胞中能够表达,72h表达量分别是52.8μg/L和70.4μg/L。  相似文献   

11.
12.
Antibodies to Neospora caninum were determined in the red fox (Vulpes vulpes) in the Pyrenees, north-eastern Spain. Sera from 53 red foxes (29 male and 24 female) were tested using a Neospora agglutination test (NAT). Seroprevalence at dilutions of 1/40, 1/80 and 1/160 was 69.8%, 47.2% and 7.5%, respectively. Sex differences were significant only at a dilution of 1:40. The high seroprevalence observed in red fox suggests that this species is highly exposed to N. caninum in this area.  相似文献   

13.
Hove, K. and H. S. Hansen: Reduction of radiocesium transfer to animal products using sustained release boli with ammoniumiron (III) - hexacyanoferrate (II). Acta vet. scand. 1993,34,287-297.– A sustained release bolus with the cesium binder ammoniu-miron(III) - hexacyanoferrate (AFCF) has been developed as a countermeasure for small ruminants grazing pastures contaminated by radiocesium (134Cs+137Cs). The boli (40-50 g) are produced by compression of a mixture of AFCF, barite and wax. The release of AFCF from boli labelled with 137Cs-iron-hexacyanoferrate complex was studied in laboratory sheep. The release rate followed first order kinetics during the 108 d of observation and decreased from 40 to 22, 110 to 35 and 280 to 25 mg d−1 in sheep treated with 1, 2 or 3 boli respectively. The efficiency of boli in reducing radiocesium transfer to meat and milk was tested in laboratory studies with goats fed 134Cs tracer. Until 40 d after treatment the transfer of radiocesium to milk was reduced by 35%, 60% and 85% in goats given 1, 2 or 3 boli, respectively. The reduction in radiocaesium transfer persisted for 90 d but with a lower efficiency. A similar relationship was found between number of boli and the reduction in radiocesium transfer to meat with an observed maximal reduction of 60%.  相似文献   

14.
鸽禽I型副粘病毒油佐剂灭活苗对肉种鸽免疫效果观察   总被引:4,自引:0,他引:4  
用鸽A/PMV-1SX株(简称SX株)制成的油佐剂灭活苗与NDV油佐剂灭活苗分别免疫肉种鸽,免疫后20天抗体水平达到峰值,抗体水平在3log2以上维持30天以上。免疫后40天用鸽SX株和新城疫强毒对两种疫苗免疫鸽分别进行攻击,两种疫苗免疫组对NDV强毒攻击的保护率均为100%,鸽A/PMV-1油佐剂灭活苗免疫组对鸽SX株攻击的保护率为100%,而NDV油佐剂灭活苗免疫组对鸽SX株攻击的保护率仅为667%。鸽A/PMV-1油佐剂灭活苗田间试验抽检48份肉种鸽血清,抗体平均值为430±116log2。  相似文献   

15.
Urolithiasis has been reported in veterinary literature in some species of the Mustelidae family, including ferrets. In this species, the most common form of urolithiasis is that caused by struvite. The current study examined the case of mixed urolith in an 8-month-old female ferret (Mustela putorius furo) with antecedents of strangury and hematuria. A cystotomy was carried out to remove the urolith, which had a rough surface and a homogeneously porous interior and was formed by a mixture of struvite (60%) and calcium oxalate dehydrated (40%).  相似文献   

16.
Forty-seven nesting green turtles (Chelonia mydas) were examined for parasitic pathogens. Four species of cardiovascular flukes (Digenea: Spirorchiidae), Learedius learedi, Hapalotrema postorchis, Monticellius indicum and Amphiorchis solus were collected from 39 of 40 of the turtles, and Neospirorchis species were identified in seven of the 47 by histological examination. The pathological changes associated with the spirorchiids and their eggs included aneurysms, arteritis of great vessels with dark nodular thickenings, endocarditis, haemorrhagic lesions, thrombi, vasculitis, and granulomatous reactions in all the turtles. Ozobranchus branchiatus (Hirudinea: Ozobranchidae) leeches were found on the skin of 27 of the 47 turtles and were associated with traumatic purulent and ulcerative dermatitis. Oesophagitis associated with Rameshwarotrema uterocrescens (Digenea: Pronocephalidae) was recorded in 11 of 43 of the turtles. Petechial haemorrhages and unspecific crater-like ulcerated lesions on the gastric mucosa associated with Charaxicephaloides species and Charaxicephalus robustus (Digenea: Pronocephalidae) were observed in four of 40 of the turtles. Cholycystitis and ectasia of mucosal glands associated with Rhytidodoides similis (Digenea: Rhytidodidae) were observed in one of the 47 turtles. Fibropapillomas were observed on the skin of one turtle and fibromas on the skin of two of them.  相似文献   

17.
The results of vaccination trials carried out on pups with maternally derived antibodies (MDA) to canine parvovirus (CPV), using a modified-live CPV-2b variant vaccine (29-97/40 strain), are reported. The vaccine was able to overcome the obstacle of MDA, and to elicit protective immunity in 100% of the pups whose antibody titres were 1:10-1:40, 83% of the pups with titres of 1:80, 57% of the pups with titres of 1:160, and even in 60% of the pups with antibody titres of 1:320.  相似文献   

18.
This study compares both versions of the nutritional requirement system determined by the National Research Council (NRC) version 1985 (NRC85) and NRC version 2007 (NRC07), for finishing lambs in feedlots. Nineteen crossbred lambs were divided in four groups representing four experimental treatments: one diet according to NRC85 and three diets according to NRC07. The diets recommended by NRC07 considers crude protein intake relative to ruminal undegradable protein at 20, 40, and 60 % levels (NRC07/20, NRC07/40, and NRC07/60). Diets were composed of Brazilian semi-arid native grass silage, soybean meal, corn, annatto byproduct, and limestone. Purchases and sales of lambs were done according to average market prices in Brazil. The economic indicators considered pointed that all treatments were viable but NRC07/20 and NRC07/60 were more profitable with similar net present values (NPVs) and internal return rates (IRRs). NRC07/20 was the best option showing an IRR of 17.20 % and a payback period (PP) of 5.07 considering a fixed annual interest rate of 6 %. Sensitivity analysis considering a 10 % raise in variable costs showed negative NPVs, IRRs inferior to the opportunity cost rates adopted and PPs that exceeded the planning horizon of 7 years for both NRC85 and NRC07/40.  相似文献   

19.
Mortality among Danish dairy cows was examined using data from the Danish Cattle Database (DCD) and a questionnaire survey. Mortality risk has increased from approximately 2% in 1990 to approximately 3.5% in 1999. The increased mortality was seen for all dairy breeds and all age groups. Mortality among older dairy cows (parity 3 and older) was approximately twice the mortality among younger cows. 30-40% of deaths were during the first 30 days of the lactation. Approximately, 58% of dead dairy cows had been euthanised. Replies from the questionnaire indicate that the proportion of euthanised cows has increased in the past 5 years. In 86% of all deaths (questionnaire survey) a primary reason could be identified; 25% were for locomotor disorders.  相似文献   

20.
In southwestern New Jersey during 1986 and 1987, common barn-owls and pigeons were captured on farmsteads and tested for Toxoplasma gondii antibodies by a modified direct agglutination test. In 1986, 3/28 (10.7%) adult and 0/124 nestling owls tested positive at titers of greater than or equal to 1:40. Additionally, 2/34 (5.9%) pigeons tested had T. gondii antibodies at titer of 1:320. In 1987, 9/38 (27.3%) adult and 18/80 (22.5%) nestling owls tested positive at titers of greater than or equal to 1:25; this includes 3/38 (7.9%) adult and 1/80 (1.3%) nestling owls that tested positive at a titer of 1:50.  相似文献   

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