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41.
This experiment was designed to study the complex of Lactobacillus rhamnosus fermented herbal and Bacillus subtilis on White Feather broiler immunity performance and impact of Escherichia coli infection.360 one-day-old broiler chickens were randomly divided into 3 groups with 4 replicates in each group and 30 chickens per replicate.The pretrial period lasted for 7 d,and the experiment lasted for 35 d.The chickens in the group Ⅰ(positive control group) and group Ⅱ(negative control group)were all only fed a basal diet,group Ⅲ was test group,by additive 1% fermented herbal preparations,groups Ⅱ and Ⅲ were intraperitoneal injection of 1 mL E.coli at 35 d,broiler mortality,immune organ index,cecalmicroflora content,immunoglobulin levels,IL-2 and IL-6 content were tested.The results showed that injection of E.coli caused massive death of chickens,group Ⅱtook up to 75.00%,it was significantly higher than groups Ⅰ and Ⅲ (P < 0.05),the mortality in group Ⅲ was significantly lower than group Ⅱ(P < 0.05),was only 23.33%.Injection of E.coli maked spleen index and thymus index of group Ⅱincreased significantly (P < 0.05),the spleen index and thymus index of groups Ⅰ and Ⅲ were no significant difference (P > 0.05).E.coli counts was significantly decreased after injectionin group Ⅲ (P < 0.05),but the number of intestinal Lactobacilli of group Ⅲ was significantly increased (P < 0.05),and inhibited the propagation of E.coli,the counts of E.coli in groups Ⅰ and Ⅲ were no significant difference (P > 0.05).At 42 d,the sIgA of the intestinal fluid in group Ⅲ were higher than that of groups Ⅰ and Ⅱ with 11.99% and 36.56%,respectively(P < 0.05).The serum IgG concentrations of group Ⅲ was higher than that of groupsⅠand Ⅱwith 14.68% and 28.15%,respectively(P < 0.05).At 42 d,the IL-2 content of group Ⅱ was the lowest,it was significantly lower than group Ⅲ(P < 0.05),the IL-6 of group Ⅲ was significantly lower than group Ⅱ(P < 0.05).  相似文献   
42.
In order to understand the main bacterial pathogen species causing dairy cow mastitis in Liaoning, as well as the characteristics of drug sensitivity of the pathogenic E.coli,the milk samples from 75 dairy cows with clinical manifestations for mastitis in certain large-scale dairy farm in Liaoning were collected.The bacteria in milk were cultured and isolated with biochemical methods and in vitro drug sensitivity tests were processed with the isolated E.coli strains.The results showed that the main bacterial pathogen for dairy cow mastitis were E.coli(separation rate 58.7%),S.aureus(64.0%)and S.agalactiae(54.7%),and multiple infection including double and triple infection were identified.The drug sensitivity tests on the isolated E.coli indicated that the E.coli isolates were highly resistant to sulfonamides(resistance rate>85%)and chloramphenicol(resistance rate>30%),and they were relatively low resistant to ampicillin(9.5%),ciprofloxacin(9.5%),ceftiofur(7.1%)and ofloxacin(4.8%).The results was able to provide reliable theoretical basis for prevention and control of dairy cow mastitis in Liaoning area.  相似文献   
43.
为了研究噬菌体尾丝蛋白gp37在识别宿主菌大肠埃希菌K12过程中的作用,PCR扩增获得gp37基因C端1 161bp序列,以EGFP为荧光标签,构建重组表达质粒pET-28a-EGFP-gp37,在大肠埃希菌BL21(DE3)中IPTG诱导表达重组蛋白EGFP-gp37,亲和层析纯化蛋白。SDS-PAGE及Western blot检测结果表明,重组蛋白EGFP-gp37在大肠埃希菌BL21(DE3)为可溶性表达,表达量占菌体总蛋白量的23%。EGFP-gp37融合蛋白与大肠埃希菌K12相互作用,激光共聚焦显微镜检测结果显示,尾丝蛋白gp37能够吸附到宿主菌K12表面,表明尾丝蛋白gp37参与宿主菌受体的识别和吸附过程。  相似文献   
44.
Hepatitis E outbreaks are a serious public health concern in developing countries. The disease causes acute infections, primarily in young adults. The mortality rate is approximately 2%; however, it can exceed 20% in pregnant women in some regions in India. The causative agent, hepatitis E virus (HEV), has been isolated from several animal species, including pigs. HEV genotypes 3 and 4 have been isolated from both humans and animals, and are recognized as zoonotic pathogens. Seroprevalence studies in animals and humans indirectly suggest that HEV infections occur worldwide. The virus is primarily transmitted to humans via undercooked animal meats in developed countries. Moreover, transfusion- and transplantation-mediated HEV infections have recently been reported. This review summarizes the general characteristics of hepatitis E, HEV infection status in animals and humans, the zoonotic transmission modes of HEV, and HEV vaccine development status.  相似文献   
45.
中黑盲蝽Adelphocoris suturalis是一种重要的农业害虫,主要为害棉花、果树和牧草等作物。昆虫保幼激素(juvenile hormone, JH)与蜕皮激素(molting hormone, 20E)是调控昆虫生殖的主要因素。本研究运用基因克隆、基因沉默(RNAi)、实时荧光定量PCR(qPCR)等技术研究蜕皮激素受体(ecdysone receptor, EcR)、超气门蛋白(ultraspiracle protein, USP)在中黑盲蝽生殖调控中的作用。结果表明,中黑盲蝽EcR基因的ORF全长1 413 bp,编码470个氨基酸。预测蛋白质分子量为53.65 kD,pI值为7.79。中黑盲蝽USP基因ORF全长1 209 bp,编码402个氨基酸。预测蛋白质分子量为44.99 kD, pI值为7.94。与对照相比,注射dsEcR、dsUSP后6~18 d的中黑盲蝽体内EcR基因、USP基因在转录水平分别被显著抑制;卵巢的挂卵量分别仅有对照组的31.5%、86.6%;单雌产卵量减少36.0%~80.4%,显著低于对照。EcR和USP基因沉默后,产卵前期与对照相比无显...  相似文献   
46.
Surveillance of hepatitis E virus (HEV) in risk groups is an important strategy to monitor its circulation pattern and to timely detect changes thereof. The aims of this cross-sectional study were to estimate the prevalence of HEV infections in pigs and humans from different regions of the country, to identify risk factors for increasing anti-HEV IgG prevalence and to characterize HEV strains. The presence of anti-HEV antibodies was assessed by commercial ELISA in serum samples from the general population, farm and slaughterhouse employees, as well as pigs sampled in the three regions of Cuba from February to September 2016. Overall, individuals with occupational exposure to swine or swine products (70/248, 28.2%) were 4 times more likely to be seropositive compared to the general population (25/285, 8.7%; OR: 4.18; p < .001). Within the risk group, risk factors included age, number of years working in a professional activity with direct exposure to swine, geographic region and distance between residence and closest professional swine setting, while wearing gloves had a protective effect. Prevalence of total anti-HEV antibodies in swine was 88.2% (165/187) and HEV RNA was detected by real-time RT-PCR in 9.2% (16/173) swine stools. All HEV strains sequenced clustered within genotype 3. Some strains clearly belonged to subtype 3a, while another group of strains was related with subtypes 3b and 3 k but partial HEV sequences did not allow unequivocal subtype assignment. These findings suggest that the high HEV exposure in Cuban individuals with swine-related occupations could be due to enzootic HEV in certain regions, direct contact with infectious animals or their products as well as environmental contamination.  相似文献   
47.
Oral squamous cell carcinoma (OSCC) is the most common oral epithelial malignancy in dogs. It exhibits locally aggressive biological behaviour with the potential to metastasize, and a reported 1-year survival rate of 0% when left untreated. Expression studies suggest that aberrant MAPK signalling plays a key role in canine OSCC tumorigenesis, which is consistent with BRAF and HRAS MAPK-activating mutations reported in some tumours. Several morphological subtypes of canine OSCC have been described, with papillary, conventional, and basaloid as the most common patterns. We hypothesized that mutational differences may underlie these phenotypic variations. In this study, targeted Sanger sequencing and restriction fragment length polymorphism assays demonstrate that up to 85.7% of canine papillary OSCC (n = 14) harbour a BRAF p.V595E mutation. Assessment of neoplastic epithelial cell proliferation using Ki67 immunolabelling (n = 10) confirmed a relatively high proliferation activity, consistent with their known aggressive clinical behaviour. These findings underscore a consistent genetic feature of canine papillary OSCC and provide a basis for the development of novel diagnostic and targeted therapeutic approaches that can improve the quality of veterinary care.  相似文献   
48.
四十种瓜菜中超氧化物歧化酶含量测定   总被引:1,自引:0,他引:1  
卢皎  金道山 《华北农学报》1993,8(2):101-104
采用化学发光法测定了40种蔬菜、瓜、果中的超氧化物歧化酶(SOD)的含量,并在此基础上探讨了9种蔬菜中维生素E、C、蛋白对SOD的影响以及它们之间的关系.还观察了蔬菜中SOD的热稳定性.结果表明,不同蔬菜、瓜、果间SOD含量的差异很大,其范围在1.26~176.10×10~(-3)g/g蛋白之间;去除脂溶性维生素E时SOD有不同程度的下降;维生素C及蛋白与SOD无明显对应关系;加热处理后样品的SOD仍得到较好保存.  相似文献   
49.
介绍了水平直元线三维参数化设计犁体曲面的方法,并利用其设计了相关的犁体曲面.与犁体曲面平面作图的方法相比较,该方法克服了犁体曲面平面作图设计的缺陷和不足,缩短了犁体曲面的设计周期,降低了设计费用,提高了设计质量,效果较好,为后续犁体曲面开发奠定了良好的基础.  相似文献   
50.
基于特征的离心泵叶片参数化三维造型   总被引:2,自引:0,他引:2  
介绍了Pro/E二次开发的方法,对离心泵叶片三维参数化造型进行研究并建立特征模型。利用定义了参数和拓扑关系的离心泵叶片的Pro/E模型文件,通过二次开发工具Pro/TOOLKIT对模型文件中定义参数进行访问,最终完成离心泵叶片的参数化三维造型。  相似文献   
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