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101.
Hiromi Takahashi Chieko Kai Yasuhiro Yoshikawa Kazuya Yamanouchi 《Comparative immunology, microbiology and infectious diseases》1995,18(4):275-281
Pseudorabies virus (PRV) was inoculated intraocularly into BALB/c mice, and the distribution pattern of cells positive for several neurotransmitters and viral antigens in the eyeball, trigeminal nerve ganglia, and superior cervical ganglia was examined immunohistochemically to clarify the neural route of the virus spread. In the eyeball, substance P (SP)- and calcitonin gene-related peptide (CGRP)-positive cells were detected in the ipsilateral iris and ciliary body, neuropeptide tyrosine (NPY)-positive cells were detected in the choloid membrane, and tyrosine hydroxylase (TH)-positive cells were detected in the ipsilateral inner nuclear layer of the retina; all these cells contained viral antigens. In the superior cervical ganglia, viral antigen-positive cells containing TH or NPY were found at bilateral sites. In the trigeminal nerve ganglia, viral antigen-positive cells containing SP or CGRP were found at bilateral sites. These findings indicated that the SP- and CGRP-positive ganglion cells of the trigeminal nerve ganglia innervating the iris or ciliary body, and the NPY-positive ganglion cells of the superior cervical ganglia innervating the iris, ciliary body, and choroid membrane served as the route for the virus spread. These findings also suggested that dopaminergic neurons, such as the TH-positive retinal cells and TH-positive ganglion cells of the superior cervical ganglia, served as the route for virus spread. 相似文献
102.
103.
【目的】分析新疆黑蜂(Xinjiang Black bee)与4个引进西方蜜蜂品种间的遗传进化关系,并通过检测基因组选择信号,发掘新疆黑蜂重要种质特性相关的候选基因。【方法】对新疆黑蜂、意大利蜜蜂(Apis mellifera ligustica)、高加索蜂(Apis mellifera caucasica)、卡尼鄂拉蜂(Apis mellifera carnica)、欧洲黑蜂(Apis mellifera mellifera)共5个蜂种50个蜂王个体和1个长白山中华蜜蜂蜂王(Apis cerana cerana)样本进行全基因组重测序数据分析,鉴定新疆黑蜂的单核苷酸多态性(single nucleotide polymorphism, SNP)标记,以长白山中华蜜蜂为外群利用邻接法构建系统进化树以阐明新疆黑蜂的进化关系,利用SNP信息进行新疆黑蜂的主成分分析、群体遗传结构分析及连锁不平衡分析;采用群体遗传分化指数(Fst)和核苷酸多样性比值(θπ)方法检测新疆黑蜂与其他西方蜜蜂群体间的选择信号,并对提取到的受选择区域候选基因进行GO功能和KEGG通路富集分析。【结果】在新疆黑蜂中共鉴... 相似文献
104.
β-葡聚糖来源广泛,主要存在于植物和微生物细胞壁中,由葡聚糖单体构成,具有多种结构,因其侧链残基种类和数量的不同而具有多种生物学功能,如通过降低炎症相关基因表达及提高免疫因子的表达发挥调节免疫的作用;通过减少脂质的产生和吸收发挥调节脂质代谢的作用;通过提高抗氧化酶、自由基、超氧阴离子的清除活性及激活Nrf2信号通路、上调抗氧化基因的表达来增强机体的抗氧化能力,发挥抗氧化作用;通过增强缺氧耐受性及提高抗氨氮应激能力、能量代谢和抗氧化酶基因的表达等发挥抗应激作用。自抗生素禁用以来,β-葡聚糖在水产动物中的研究和应用逐渐深入,β-葡聚糖在预防水产动物疾病和减少抗生素使用等方面发挥着重要作用。在水产养殖中,β-葡聚糖可通过提高消化酶活性、改善肠道结构、优化肠道菌群及增强非特异性免疫力来提高水产动物生长性能,β-葡聚糖的联合使用比添加单一种类的免疫刺激剂具有更好的免疫效果。作者就β-葡聚糖的结构特征、生物学活性、作用机制及在水产动物中的应用进行了综述,并对β-葡聚糖今后的发展方向进行了展望,为实现水产动物生态健康养殖提供材料。 相似文献
105.
107.
Oral-vaccine microspheres based on formalin-inactivated Actinobacillus pleuropneumoniae serotype 1 (AP-1) antigens and enteric-coated polymers were prepared using a co-spray drying process. We evaluated using this for a peroral vaccine. We measured specific-antibody titers and protection from challenge in mouse and pig models. In mice (24 per group), a subcutaneous aluminum-adjuvant vaccine or oral vaccination with three doses of AQ6-AP microspheres provided similar protection against intranasal challenge with 5 x 10(8) colony-formation units (cfu) of AP-1 bacterial culture broth. Two weeks after four oral vaccinations with 600 mg of AQ6-AP microsphere acetate solution (containing formalin-inactivated AP-1 antigens of 1.0 x 10(10) cfu bacterial broth), pigs (9 per group) were challenged intranasally with 1 ml of AP-1 bacterial culture broth (5 x 10(9) cfu). The clinical signs, percentage of pig survival ratio, lung lesion areas, and microscopic examinations indicated that the oral AQ6-AP vaccine provided more protection than vaccinating pigs intramuscularly with AP-1 aluminum vaccine. 相似文献
108.
The Epidemiology and Characteristics of Q fever and Co‐infections with Scrub Typhus,Murine Typhus or Leptospirosis in Taiwan: A Nationwide Database Study 下载免费PDF全文
C.‐H. Lai W. Sun C.‐H. Lee J.‐N. Lin M.‐H. Liao S.‐S. Liu T.‐Y. Chang K.‐F. Tsai Y.‐C. Chang H.‐H. Lin Y.‐H. Chen 《Zoonoses and public health》2017,64(7):517-526
Q fever (QF) is a worldwide zoonosis associated with outbreaks. Only a few nationwide studies regarding the surveillance and epidemiology of human QF have been reported. Although QF is endemic in Taiwan, a nationwide database investigation of the epidemiology and characteristics of QF and its associations with scrub typhus (ST), murine typhus (MT) and leptospirosis (LS) has never been reported. We analysed nationwide databases of suspected QF, ST, MT and LS cases from October 2007 to December 2014 obtained from the Centers for Disease Control, Taiwan. A total of 468 (4.2%) QF cases were identified among 11 109 suspected QF cases. QF cases were mainly distributed in the southern and Kaohsiung–Pingtung regions but rarely in the eastern region. Compared to non‐QF cases, QF cases had significantly higher percentages of males (88.7 versus 66.2%) and high‐risk occupations (farming, animal husbandry or veterinary medicine) (16.2 versus 10.5%). But the percentages of specific animal contact, including cattle (0.6 versus 0.8%) and goats (0.9 versus 1.0%), were low in both. The majority of suspected QF cases (89.4%) were simultaneously suspected with ST, MT or LS, and the combinations of suspected diseases differed between regions. The number of suspected QF cases from the eastern region decreased since 2009, which was not observed in other regions. A total of 1420 (12.8%) cases had confirmed diseases, including QF (453, 4.1%), QF+ST (7, 0.06%), QF+MT (4, 0.04%), QF+LS (4, 0.04%), MT (186, 1.7%), ST (545, 4.9%), ST+LS (11, 0.1%) and LS (210, 1.9%). Compared to cases of unknown disease, QF cases had larger percentages of high‐risk occupations (16.2 versus 9.6%) but similar histories of animal contact (29.8 versus 25.1%). QF is an endemic disease in southern Taiwan. It is difficult to differentiate QF from ST, MT or LS only by high‐risk occupations and history of animal contact, and co‐infection of QF with these diseases should be considered. 相似文献
109.
采用响应曲面法对常温饮用型酸乳的配方进行优化。用Plackett-Burman设计法研究全脂乳粉与乳清粉的蛋白比例、琼脂、淀粉、果胶、果糖和稀奶油添加量6 个因素对酸乳黏度及持水力的影响,筛选出影响酸乳黏度和持水力的显著因素,用Box-Behnken试验设计优化最佳配方。结果表明:全脂乳粉与乳清粉的蛋白比例、琼脂、淀粉及果胶添加量是影响常温饮用型酸乳黏度和持水力的显著因素(P<0.05);经过响应面试验设计建立黏度、持水力和4因素的模型,对此模型进行求解得到最佳配方为全脂乳粉与乳清粉的蛋白比例5∶1、琼脂 相似文献
110.