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91.
中草药添加剂对仔猪cAMP/cGMP及免疫功能的影响   总被引:13,自引:0,他引:13  
 对试验猪的有关测定表明,中草药添加剂可明显提高仔猪血液cAMP的含量及cAMP/cGMP的比值,分别提高164.07%和55.79%. 和对照组比较,血液中免疫球蛋白(IgG)的含量升高58.7%.对白细胞数量及分类计数发现,试验组相关值远高于添加常规抗生素的仔猪,其中嗜酸性白细胞升高437.5%.  相似文献   
92.
根据GenBank中注册的猪IgG H链基因cDNA CH2 CH3序列(SSU03780),设计了含KpnⅠ和HindⅢ酶切位点的一对引物,采用反转录-聚合酶链式反应(RT-PCR)法从北京长白杂交猪肠系膜淋巴结细胞扩增猪IgG H链基因CH2 CH3序列.将PCR产物纯化回收后,插入到含LacZ基因的克隆载体pGEM-T Easy中,转化大肠杆菌JM 109感受态细胞,经KpnⅠ和HindⅢ双酶切及PCR鉴定,筛选出阳性克隆.将所克隆的目的片断亚克隆到原核表达载体pQE 30,构建重组质粒pQE 30/PIgG CH2 CH3.将重组表达质粒转化大肠杆菌JM 109感受态细胞,筛选阳性克隆,经IPTG诱导表达后,进行聚丙烯酰胺凝胶电泳(SDS-PAGE)分析.结果表明,本研究克隆了猪IgG H链基因CH2 CH3序列,全长663 bp,编码221个氨基酸,利用Gentyx version 6.0软件将CH2 CH3基因的核苷酸序列与GenBank中的参考序列比较,其核苷酸序列同源率为99.551%,推导的氨基酸序列同源率为100%.将pQE 30/PIgG CH2 CH3转化JM 109感受态细胞,表达的融合蛋白相对分子质量约为26.95 ku,经IPTG诱导2 h,表达量约占菌体总蛋白41.5%.  相似文献   
93.
While testing several samples of onion and of vegetatively propagated garlic, sand leek and shallot from a number of countries, virus isolates with unusually flexuous particles were obtained by mite (Aceria tulipae) or sap transmissions. No aphid-borne poty-or carlavirus was transmitted by mites, and mite-borne virus isolates could not be transmitted by aphids. The mite-borne isolates did not react with antisera to aphid-borne potyviruses ofAllium spp. or with the Agdia potyvirus group monoclonal. In contrast to the mite-borne onion and garlic mosaic viruses reported in the literature, our mite-borne isolates induced no visible or only very mild symptoms inAllium spp., except isolates from shallot ‘Santé’ which caused diffuse striping. Heavily mite-infested test plants or plant samples showed streaking and malformation due to mite feeding (tangle-top). The mite-borne virus isolates could be classified with test plants and a discriminating antiserum into three groups, representing two viruses and a strain of one of them. They are tentatively named onion mite-borne latent virus (OMbLV), garlic strain of this virus (OMbLV-G), and shallot mite-borne latent virus (SMbLV). Mite transmission, length of virus particles (ca. 700 to 800 nm), and the presence of granular inclusion bodies in infected tissue indicate that the viruses belong to the mite-borne genusRymovirus of the familyPotyviridae. OMbLV from shallot and onion, and OMbLV-G from garlic and sand leek, can be assayed onChenopodium murale but differ in their natural hosts. They are very common. SMbLV, to whichC. murale does not react, was isolated from shallot originating from Asia and Russia.  相似文献   
94.
用驴制备抗猪瘟病毒(HCV)免疫球蛋白,预防和治疗猪HCV感染,制备HCV抗原复合物,通过免疫驴,用纯化方法从驴血清中提取特异性抗体(IgG),经过理化学检定,血清学,动物效力实验。免疫驴均可产生特异IgG,Dot-ELISA效价大于1:640(IgG浓缩浓度为60mg/mL);可保护猪兔受HCV攻击;室温保存半年,4℃两年效价不变。已成功地应用HCV免疫驴制备出高效价特异性抗HCV-IgG。  相似文献   
95.
96.
本文通过人工复制的鸡球虫病鸡,利用免疫组化技术等方法,检测了柔嫩艾美耳球虫(E.tenella)初次感染雏鸡后,盲肠局部和免疫器官中IgG生成细胞数的动态变化。结果表明:攻毒后雏鸡盲肠粘膜、脾脏、法氏囊、盲肠扁桃体中的IgG生成细胞分别于第3、3、3、2d开始增殖,在第12、12、16、9d达到峰值,随后即开始下降,盲肠扁桃体中的IgG生成细胞数在第22d仍高于对照组,且差异显著(P<0.05)。  相似文献   
97.
Eastern equine encephalitis and Venezuelan equine encephalitis are endemic neglected tropical diseases in the Americas, causing encephalitis in both horses and humans. In 2013, a cross-sectional study was performed in 243 horses located in the highlands and lowlands throughout Costa Rica. Serum samples were analyzed with an IgG ELISA and confirmed by the plaque-reduction neutralization test (PRNT80). Venezuelan equine encephalitis virus (VEEV) and Eastern equine encephalitis virus (EEEV) overall seroprevalences by the PRNT80 were 36% (95% confidence interval [CI]: 29.9–42.5; 78/217 horses) and 3% (95% CI: 1.3–5.9; 6/217 horses), respectively. Both the viruses occurred in the lowlands and highlands. Rainfall and altitude were associated with VEEV seropositivity in the univariate analysis, but only altitude <100 meters above sea level was considered a risk factor in the multivariate analysis. No risk factors could be identified for the EEEV in the multivariate analysis. This is the first study that estimates the seroprevalence of the EEEV and VEEV in Costa Rican horses. The VEEV is widely distributed, whereas the EEEV occurs at a much lower frequency and only in specific areas. Clinical cases and occasional outbreaks of both viruses are to be expected.  相似文献   
98.
按中兽医组方原则配制加工成中草药饲料添加剂A和B,分别按0.5%、1%、2%3个浓度添加,设抗生素和空白对照组,对28日龄土杂鸡随机分组进行饲养试验,分别于42、56、70日龄测定IgG含量。结果显示:中草药添加剂能显著增加土杂鸡IgG水平,而且随着日龄的增加有增高的趋势。  相似文献   
99.
The objective of this study was to evaluate the passive transfer of maternal antibodies to calves following vaccination of pregnant cows with an inactivated Mannheimia haemolytica (MH) and Bovine herpes virus type 1 (IBR) vaccine (Bovilis® MH + IBR). Sixty-two pregnant cows were allocated at random to two groups; one group was retained as a negative control group (T01), while the other group (T02) was vaccinated with Bovilis® MH + IBR on two occasions during their third trimester of pregnancy. Following calving, blood samples were collected from calves for the measurement of serum antibody titres to IBR and MH, with samples collected prior to suckling (Day 0) and on days 5 (±2), 14 (±3), 28, 56, 84, 112, 140, 168, 196, 224, 252 and 280. The group mean IBR blocking percentage remained low for T01 calves (calves born to T01 cows) between days 0 and 224 (range 4.5%–15.4%), while the group mean IBR blocking percentage increased for T02 calves (calves born to T02 cows) from 14.3% on Day 0 to 94.9% on Day 5 and remained significantly higher than T01 calves up until Day 252. The group mean MH titre (Log2) for T01 calves increased after suckling to 8.9 on Day 5, before declining and remaining stable (range 5.0–6.5). The group mean MH titre for T02 calves increased after suckling to 13.6 on Day 5 and then gradually declined; however, it remained significantly higher than T01 calves between days 5 and 140. Outcomes from this study have confirmed that colostral transfer of IBR and MH antibodies to newborn calves was successful and a high level of passive immunity was acquired by calves.  相似文献   
100.
免疫途径对鸡全身性免疫应答水平的影响   总被引:1,自引:0,他引:1  
本研究观察了蛋白抗原的自由饮水、皮下注射和强饲途径对鸡免疫应答能力的影响。结果显示,注射免疫和饮水免疫处理组所产生的IgG应答明显强于强饲免疫处理组和未免疫的对照组(P〈0.05),这说明抗原接触途径中的自由饮水免疫方式与注射免疫方式同样有效,这为商品家禽接种纯化的蛋白抗原提供了一种崭新的途径。  相似文献   
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