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92.
XU Li-pu WANG Xiao-liang ZHANG Wen PAN Yong JING Hong-li WANG Jing-bo WANG Shu CAO Huan WANG Peng NA Li-hai JIANG Yu-lin 《中国畜牧兽医》2017,44(2):613-618
An acute infectious diseases occurred in a koi farm in Fangshan district, Beijing, and it resulted in mortalities of more than 50%.The main symptoms of sick koi were gills necrosis, kidney erosion and edema,which were similar to the clinical signs of koi herpes virus disease (KHVD).But PCR tests showed negative results for KHV. For further diagnosis, bacterial cultures, transmission electron microscopy studies, virus isolation and PCR tests were used. Electron microscopic observation revealed pox virus particles having a size of about 200 nm×400 nm in the kidney. 548 and 180 bp fragments were amplified from organs of sick koi by PCR method using specific primers of carp edema virus (CEV). The fragments were sequenced and analysed. The results showed that they were shared 100% nucleotide identity with CEV-H504. All the results indicated that this disease was carp edema virus disease, caused by a kind of pox virus, CEV. This was the first report on the CEV of cultured koi in China. 相似文献
93.
Chui Ching Wong Su Ming Thean Youming Ng Joanne Su Lin Kang Tong Yong Ng Man Ling Chau Tse Hsien Koh Kwai Peng Chan 《Zoonoses and public health》2019,66(7):773-782
Hepatitis E virus (HEV) causes 20 million infections worldwide yearly, of which only about 3.3 million are symptomatic. In developed Asian countries, HEV strains detected in human sera and in food sources were genetically similar, suggesting that indigenous HEV infections may be largely food‐borne. To assess the burden of hepatitis E in Singapore, we performed a seroepidemiologic study of the infection. Additionally, we carried out HEV genotyping on archived, residual HEV IgM‐positive serum samples collected between 2014 and 2016 (n = 449), and on pig liver samples (n = 36) purchased from wet markets and supermarkets. Our study shows a rise in hepatitis E incidence (IgM) from 1.7 to 4.1 cases per 100,000 resident population from 2012 to 2016 and an increase in hepatitis E IgG positivity rate among residents from 14% in 2007 to 35% in 2016. Other findings also suggest the epidemiology of hepatitis E in Singapore has shifted, from it being mainly a disease imported from the Indian subcontinent, to one that is now increasingly prevalent in our resident population. Genotypes obtained from 143 human samples identified the majority to be genotype 3 (n = 121), 21 to be genotype 1 and one to be genotype 4. Further phylogenetic analyses suggest genotype 3a to be the cause of indigenous infections in residents, which showed genetic similarity to the genotype 3a strains detected in pig livers. This link between the strains in the majority of human samples and those in pig livers consumed by the public suggests a possible food‐borne route of HEV infection in Singapore. 相似文献
94.
基于OBE理念下食品营养学课程设计与教学方式的探索 总被引:2,自引:0,他引:2
成果导向教育(OBE)是一种符合当前社会对实践应用型人才需求的教育培养模式。以淮阴师范学院生命科学学院为例,探讨了“食品营养学”课程在人才培养目标达成度、教学内容设计、知识模块构建、教学方法应用,以及课程考核5个方面基于OBE理念下的改革尝试,以期为地方高校食品专业和农林生物专业该课程的教学提供借鉴和参考,为探索培养区域型高素质人才提供新的思路。 相似文献
95.
Juzuo Zhang Liqun Xue Ang Nie Qing Yang Xuan Peng Zhilong Chen Lisha Yang Yang Xie Anwen Yuan Junfei Xu 《Reproduction in domestic animals》2020,55(11):1479-1489
Non-infectious prenatal mortality severely affects the porcine industry, with pathological placentation as a likely key reason. Previous studies have demonstrated that peroxisome proliferator-activated receptor gamma (PPARγ) deficiency causes defects in the uteroplacental vasculature and induces embryonic losses in mice. However, its role in porcine placental angiogenesis remains unclear. In the present study, PPARγ expression was investigated in porcine uteroplacental tissues at gestational day (GD) 25, GD40 and GD70 via quantitative polymerase chain reaction (qPCR), Western blot and immunohistochemistry (IHC). Moreover, the roles of PPARγ in porcine placental angiogenesis were investigated using a cell model of porcine umbilical vein endothelial cells (PUVECs) to conduct proliferation, migration and tube formation assays in vitro and a mouse xenograft model to assess capillary formation in vivo. The results showed that PPARγ was mainly located in the glandular epithelium, trophoblast, amniotic chorion epithelium and vascular endothelium, as indicated by the higher expression levels at GD25 and GD40 than at GD70 in endometrium and by higher expression levels at GD40 and GD70 than at GD25 in placenta. Moreover, PPARγ expression was significantly downregulated in placenta with dead foetus. In PUVECs, knocking out PPARγ significantly inhibited proliferation, migration and tube formation in vitro and inhibited capillary formation in mouse xenografts in vivo by blocking S-phase, promoting apoptosis and downregulating the angiogenic factors of VEGF and its receptors. Overall, the spatiotemporal heterogeneity of PPARγ expression in porcine uteroplacental tissue suggests its vital role in endometrial remodelling and placental angiogenesis, and PPARγ regulates placental angiogenesis through VEGF-mediated signalling. 相似文献
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本研究以新城疫病毒(NDV)V蛋白羧基端结构域(Vc)的重组蛋白为包被抗原,建立了用于检测NDV V蛋白抗体的间接ELISA方法,并采用该方法检测了鸡群免疫或接毒后血清中的V蛋白抗体水平。结果显示:两组不同NDV灭活疫苗组在免疫后的3周内检测结果均为阴性;两组灭活疫苗免疫3周后再人工感染NDV强毒的鸡群,攻毒后第7、14和21 d,NDV阳性率分别为60%、80%、70%和50%、80%、70%;两组不同的NDV弱毒疫苗免疫组鸡群,仅在免疫后第21 d阳性率分别为20%和10%。以上结果表明,NDV疫苗免疫组与强毒感染组的V蛋白抗体阳性率存在明显差异,本方法可在群体水平上区分新城疫疫苗免疫与强毒感染鸡群,为NDV血清学诊断和流行病学调查提供了一种新的检测手段。 相似文献
100.
从配方和工艺2 个角度研究颗粒型燕麦牛乳的稳定性,以离心沉淀率、黏度和感官评分作为评价指标。结果表明:对稳定剂进行优化后,得到最佳复配稳定剂配方为结冷胶添加量0.04%、卡拉胶添加量0.020%、羧甲基纤维素钠添加量0.020%、微晶纤维素添加量0.20%;对配料温度、水合时间、均质压力和灌装温度4 个影响体系稳定性的工艺点进行单因素试验,继而设计正交试验,得到最佳参数组合为配料温度50 ℃、水合时间40 min、均质压力30 MPa、灌装温度15 ℃,此条件下产品稳定性最佳,口感良好。 相似文献