共查询到20条相似文献，搜索用时 15 毫秒
1.
为了获得安全性好,对出血性大肠杆菌具有良好免疫保护作用的疫苗株,本实验以构建的O157Δler/stx基因缺失突变株为载体,将决定特异性粘附的cae全基因插入到质粒pBR322：：stx1/2B中,构建了基因工程茵O157Δler/stx(pBR322：：stx1/2B：：eae),对该基因工程菌进行生物学特性分析,实验结果表明,该菌正常培养可表达eae；具有粘附HEp-2细胞的特性；该菌培养上清对Vero细胞没有毒性作用；给小鼠口服接种该工程菌后可在肠道中定居至少10d；14日龄小鼠口服活菌量为5×10~9CFU/只,小鼠生长正常,没有出现任何临床症状；该菌通过口服免疫小鼠可以诱导肠道粘膜免疫应答和体液免疫应答。这些结果表明,该工程菌安全性好,免疫原性强,是有价值的预防EHEC O157感染的基因工程疫苗候选株。 相似文献
2.
Zhi-qiang Li Dan Gui Zhi-hua Sun Jun-bo Zhang Wen-zhi Zhang Hui Zhang Fei Guo Chuang-fu Chen 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(4):467-473
Brucellosis is a zoonotic disease that causes animal and human diseases. Vaccination is a major measure for prevention of brucellosis, but it is currently not possible to distinguish vaccinated animals from those that have been naturally infected. Therefore, in this study, we constructed the Brucella (B.) abortus 2380 wbkA mutant (2308ΔwbkA) and evaluated its virulence. The survival of 2308ΔwbkA was attenuated in murine macrophage (RAW 264.7) and BALB/c mice, and it induced high protective immunity in mice. The wbkA mutant elicited an anti-Brucella-specific immunoglobulin G response and induced the secretion of gamma interferon. Antibodies to 2308ΔwbkA could be detected in sera from mice, implying the potential for use of this protein as a diagnostic antigen. The WbkA antigen would allow serological differentiation between infected and vaccinated animals. These results suggest that 2308ΔwbkA is a potential attenuated vaccine against 16M. This vaccine will be further evaluated in sheep. 相似文献
3.
《中国兽医学报》2016,(11):1829-1835
为开发新型重组减毒鸡白痢沙门菌口服活疫苗载体。本研究以pcDNA3.1-Zeo(+)质粒为基础,用沙门菌asd基因替代其氨苄抗性基因Amp,构建不含抗性基因的真核互补质粒pcD-asd;再将互补质粒pcD-asd电转入沙门菌ΔcrpΔasdC79-13,构建ΔcrpΔasdC79-13(pcD-asd)平衡致死系统,研究其生物学特性,进一步将报告基因EGFP克隆入pcD-asd,构建重组菌株ΔcrpΔasdC79-13(pcD-asd-EGFP),感染鸡胚成纤维(CEF)细胞,Western blot分析该系统递呈外源抗原的能力。PCR、酶切及测序结果表明ΔcrpΔasdC79-13(pcD-asd)平衡致死系统构建成功;生物学特性鉴定结果表明,其血清型与亲本株ΔcrpΔasdC79-13及野生株C79-13保持一致;其生化特性与亲本株基本相近,但与野毒株相比发生明显变化;生长速度也更为缓慢,对氨苄抗生素敏感;重组菌株ΔcrpΔasdC79-13(pcD-asd)的LD50较野生株C79-13降低了3.4×104倍;Western blot结果发现,重组菌株感染CEF细胞后,可表达大小约为27 000EGFP蛋白。以上结果证实,本研究成功构建了新型重组减毒鸡白痢沙门菌ΔcrpΔasdC79-13(pcD-asd)株,其能够有效递呈外源抗原,该重组菌株有潜力作为安全、稳定、高效表达外源基因的口服重组活疫苗载体。 相似文献
4.
非洲猪瘟（African Swine Fever,ASF）是由非洲猪瘟病毒（African swine fever virus,ASFV）感染引起的猪高度致死性传染病,迄今全球还没有能预防它的有效疫苗。目前基因缺失减毒活疫苗和亚单位疫苗是最具潜力的疫苗研发策略。据报道,越南正式批准了ASFV基因缺失弱毒疫苗NAVET-ASFVAC （ASFV-G-AI177L）在其全国范围内使用。ASFV-G-AI177L疫苗株是首个能诱导产生免疫且不排毒的毒株,针对越南地方品种猪具有良好的安全性并可抵抗母本强毒株（ASFV-G）的攻击;在疫苗接种后21 d可产生全面保护,并且大剂量接种安全,带毒时间小于90 d,连续5次传代未观察到毒力返祖。但是临床条件下ASFV-G-AI177L疫苗株仍存在水平传播和病毒血症逐代升高的风险,并且对野猪和妊娠母猪缺乏安全性评价。本文针对越南自美国引进的ASFV-G-AI177L毒株相关临床研究数据进行综述,以期为我国ASF疫苗研究及防控政策制定提供参考。 相似文献
5.
非洲猪瘟（Afcrian swine fever,ASF）是由非洲猪瘟病毒（African swine fever virus,ASFV）感染引起的烈性传染病。近日,越南正式将经临床试验验证的非洲猪瘟弱毒疫苗AVAC ASF LIVE(ASFV-G-ΔMGF)在其全国推广使用。本文对越南非洲猪瘟弱毒疫苗ASFV-G-ΔMGF相关研究数据进行了总结分析,分别从ASFVG-ΔMGF株攻毒保护能力评价、传代细胞培养株临床动物实验、野猪口服接种试验、毒力返强验证等方面,结合国内相关ASFV基因缺失株试验数据进行了分析。总结分析发现：越南上市的ASFV-G-ΔMGF疫苗株,二次免疫接种后攻毒保护效果更好,但在对野猪的口服接种评价中,其口鼻接种效果存在不确定性;随着疫苗株在动物体内的不断传代,其存在毒力返强和毒株变异风险,导致接种猪只临床症状明显;ASFV-G-ΔMGF株虽然有较好的攻毒保护能力和可靠的生产优势,但仍缺乏相关研究数据,特别是在垂直传播、交叉保护、基因突变等方面。后续仍需对ASFV-G-ΔMGF株的临床应用效果进一步评价。 相似文献
6.
J C Maillard S J Kemp H Leveziel A J Teale R Quéval 《Revue d'élevage et de médecine vétérinaire des pays tropicaux》1989,42(2):275-281
Lymphocyte antigen (BoLA) typing on 247 Baoule cattle (Bos taurus) and 106 Sudanese zebus (Bos indicus), allowed us to determine gene frequencies of 43 class 1 specificities, as international "W" and European "EU", as African local from Kenya "KN" and Burkina Faso "BF". In comparing these frequencies, it appears that some specificities could be considered as significant breed markers for Baoule cattle and zebus. 相似文献
7.
本刊辑 《江西畜牧兽医杂志》2019,(1)
<正>1月28日,农业农村部发布第129号公告,公告表示,根据《兽药管理条例》和《兽药注册办法》规定,经审查,批准普莱柯生物工程股份有限公司等15家单位申报的猪伪狂犬病灭活疫苗(HN1201-ΔgE株)等6种兽药产品为新兽药,核发《新兽药注册证书》,发布产品试行规程、质量标准、说明书和内包装标签,自发布之日 相似文献
8.
1范围
1.1本标准的第一部分适用于蜜蜂生产的所有蜂蜜,并涵盖加工且最终供直接食用的各种类型的蜂蜜产品.本标准的第二部分适用于工业用蜂蜜和作为其他食品成分的蜂蜜. 相似文献
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《中国兽医学报》2020,(10)
为确保从挪威进口至四川的冰鲜大西洋鲑鱼的卫生与安全,防止有害生物因子传入我国。本试验参照OIE及相关国内行业标准推荐的水生动物疾病诊断手册中分子生物学检测方法,采用TaqMan荧光定量RT-PCR结合HE基因中高度多态区域(HPR)克隆测序等诊断方法,对从挪威进口至四川成都的某批次抽检去内脏冰鲜大西洋鲑鱼进行传染性鲑鱼贫血症病毒(ISAV)的检测。结果显示,该进口大西洋鲑鱼鱼肉中检出HPR缺失型ISAV,且其HPR区间存在51 bp的碱基缺失,基于HPR的序列分析结果提示其与分离自挪威的ISAV9和9/93 HPR缺失型ISAV的亲缘关系最近。结果表明,这是我国国内首例通过分子生物学方法,从进口大西洋鲑鱼鱼肉中检出HPR缺失型ISAV的案例,该结果警示各大水生动物检疫机构应重视对进口的去内脏冰鲜大西洋鲑鱼中ISAV的筛查,严防该病毒进入我国。 相似文献
11.
1. Studies were conducted to determine the effects of anticoagulants and storage (4°C) on the PCV of blood samples from Nigerian domestic fowl (DF) and the guinea fowl (GF).
2. Citrate significantly reduced pre‐storage PCV of the DF in comparison with the effect of ethylenediamine tetra‐acetic acid (EDTA).
3. It further decreased (P<0.05) the PCV of the blood of DF and GF over 3 d of storage; this was similar to the effect of EDTA on the PCV of the GF blood.
4. Citrate and oxalates induced haemolysis of blood of the DF and the GF in storage faster than EDTA, but overall the haemolysis was more pronounced from red cells of the GF than from those of the DF.
5. The mean fall in the PCV of the DF was significant at 3.0 mg EDTA/ml of blood in contrast to the fall in the PCV of the GF blood. 相似文献
12.
《农村养殖技术》2001,(12)
品 名 规 格 单价 行品 名 规格 单价 行势北貉皮(生皮)北貉皮(熟皮)东北红狐皮(生板)东北红狐皮(熟板)国产蓝狐(生板)国产蓝狐(熟板)进口蓝狐(熟板)国产银狐(生板)国产银狐(熟板)进口银狐(熟板)国产水貂皮(公皮、生皮)卜号(90cm以上) 370 l号(90cm以上) 380 头路 210 头路 240l号(88~97cm改良)540l号(88~97 cm受良)5600000号 11002号(79~88cm) 5402号(79~88em) 560000号 1000O号 200国产水貂皮(公皮、熟皮) O号 210国产母貂皮(生皮) 混路 90国产母貂皮(熟皮) 混路 100兔皮(白色) 夏皮 6獭兔皮 A级(33"42em)35獭兔皮 B级(30"36em)23獭兔皮… 相似文献
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Recent publications dealing mainly with the kinetics of antiparasitic and antibacterial agents, NSAIDs, and other drugs in camels are briefly reviewed. The kinetic data for most of these drugs indicated that they have longer absorption and elimination half-lives and slower systemic clearance in the camel compared to other animals. This corroborates earlier reports that suggested that the activities of drug-metabolizing enzymes and the capacity to biotransform and eliminate xenobiotics is lower in camels than in other ruminants. There is a clear need to establish basic kinetic data for the camel in order to avoid extrapolation of drug dosage regimens and withdrawal times from data for other animals, as this may result in irrational use of drugs in camels. 相似文献
15.
ELISA是检测BVD/MD的一种快速、灵敏、可靠而经济的血清学诊断方法,其结果与病毒中和试验相符合,而与补体结合试验却不十分相符。有人认为ELISA比中和试验更少受试验用毒株的影响。 本试验既可用间接法,也可用阻断法。建立该试验的主要困难在于制备出有足够效 相似文献
16.
During the past decade, Fascioloides magna, the large American liver fluke, has spread within free-living deer in wetlands of the Danube in Lower Austria. The aim of this study was to determine the current infection rates with F. magna and other digenean parasites in the intermediate host snail Galba truncatula from risk areas in Lower Austria. A total of 3444 G. truncatula were collected and examined microscopically for the presence of digenean trematodes. A set of randomly selected snails and isolated trematode stages were also investigated molecular biologically by PCR and sequencing. Digenean parasites were detected with a prevalence of 2.41% (1.83% Paramphistomoidea; 0.46% Echinostomatoidea; 0.09% Strigeida; 0.06% Plagiorchiida). F. magna was found with an overall prevalence of 0.23%, which may indicate a recovery of the parasite population in spite of an ongoing triclabendazole treatment programme. Moreover, high risk areas and a seasonality of infections were observed. 相似文献
17.
San Martín MF Soraci A Fogel F Tapia O Islas S 《Veterinary research communications》2002,26(4):323-332
The influence of clofibrate on the stereoconversion of fenoprofen (FPF) was studied in guinea pigs. This hypolipidaemic agent has been related to some biochemical changes in the liver leading to an increase in the chiral inversion process. Two groups of animals (n = 6 per group) were pretreated with oral doses of clofibrate (280 mg/kg per day) for three days and were then given (R)- or (S)-FPF (5 mg/kg, IV). The FPF enantiomers were extracted from the guinea-pigs' plasma using a solid phase procedure and analysed by HPLC with previous derivatization with L-leucinamide. Pretreatment with clofibrate increased the chiral inversion of (R)-FPF in favour of the pharmacologically active (S)-FPF enantiomer. Before this metabolic interaction can be applied to therapy with fenoprofen, the toxic effects of (S)-(+)-FPF on the gastrointestinal and renal tracts and the interference by (R)-(–)-FPF with the metabolism of lipids should be thoroughly evaluated. 相似文献
18.
Bartosz WOJCIECHOWICZ Genowefa KOTWICA Justyna KOLAKOWSKA Anita FRANCZAK 《The Journal of reproduction and development》2013,59(1):49-58
Steroid hormones are produced by the porcine uterus. We hypothesized that the uterus in
pigs possesses active 3β-hydroxysteroid dehydrogenase/Δ5-Δ4
isomerase (3β-HSD) responsible for progesterone and androstenedione production, that
uterine steroids may supplement the amount of steroid hormones produced by embryos and
corpus luteum and that these steroids are necessary for maintenance of pregnancy. In this
study, we examined 1) endometrial and myometrial expression of 3β-HSD
mRNA, 2) uterine 3β-HSD protein activity and 3) in vitro production of
A4 and P4 by uterine slices harvested from pigs on days 10 to 11,
12 to 13 and 15 to 16 of pregnancy and the estrous cycle. The expression of
3β-HSD and the presence and activity of 3β-HSD protein were different
in the endometrium and the myometrium during the examined periods of pregnancy and the
estrous cycle. Production of A4 by the endometrium and myometrium was highest
on days 12 to 13 of pregnancy and the estrous cycle. Endometrial secretion of
P4 did not differ in the course of early pregnancy and on the respective days
of the estrous cycle. The gravid myometrium was the highest source of P4 in
pregnant pigs on days 12 to 13. The release of P4 by the cyclic myometrium rose
during the examined days of the estrous cycle. The steroidogenic activity of the uterus,
as described in this study, may support early pregnancy or the luteal phase of the estrous
cycle in pigs. 相似文献
19.
为研究羊免疫布鲁氏菌病基因缺失活疫苗(M5-90Δ26株)和弱毒疫苗(S2株)效果,选取220只3～12月龄的布病阴性羊,随机分为3组,免疫48h内观察疫苗副反应,并在免疫7d、14d、30d、90d后采血进行抗体检测。结果显示：免疫48h内,M5-90Δ26注射组和S2口服组均未出现发烧症状,M5-90Δ26注射组1只试验羊出现采食量下降,S2口服组未见羊群采食量下降。M5-90Δ26注射组免疫7d抗体阳性率97%,免疫14d和30d抗体阳性率100%;S2口服组免疫后7d抗体阳性率49%,免疫30d抗体阳性率最高(81%);对照组未检测到布病抗体阳性。综上所述,布病M5-90Δ26在免疫后抗体水平上优于S2株,但可能存在副反应,建议免疫前观察羊状态,严格按照疫苗说明书进行免疫。 相似文献
20.
禽流感病毒分离株 A/Chicken/Wangcheng/4/2001(H9N2)核蛋白基因(NP)的克隆和序列分析 总被引：1，自引：0，他引：1
用无特定病原体 (ＳＰＦ)鸡胚增殖禽流感鸡体分离株Ａ／Ｃｈｉｃｋｅｎ／Ｗａｎｇｃｈｅｎｇ／４／２００１(Ｈ９Ｎ２)(ＷＣ２００１),提取病毒总ＲＮＡ。根据已发表的Ａ型流感病毒株ＮＰ基因序列 ,设计一对引物 ,运用反转录 -聚合酶链反应(ＲＴ -ＰＣＲ)扩增该病毒分离株的ＮＰ基因 ,克隆后进行序列测定。序列分析表明 ,扩增的ＮＰ基因为相应的开放阅读框架。ＷＣ２００１株ＮＰ基因序列与数株Ａ型流感病毒ＮＰ序列进行比较 ,相互间同源性在８０%左右 ,其中与Ａ／Ｄｕｃｋ／ＨｏｎｇＫｏｎｇ／Ｙ２８０／９７(Ｈ９Ｎ２)有很高的同源性 ,而与人流感病毒株和猪流感病毒株差异较大 ,显示禽流感病毒特征。 相似文献