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121.
O型口蹄疫病毒固相竞争ELISA抗体检测方法的建立 总被引:2,自引:0,他引:2
本研究建立了O型口蹄疫病毒固相竞争ELISA抗体检测方法,确立了O型口蹄疫病毒固相竞争ELISA抗体检测方法检测O型口蹄疫血清阴阳性判定标准:抗体效价大于或等于1:32时判为O型口蹄疫抗体阳性;1:16~1:32时判为O型口蹄疫抗体可疑。检测131份阴性血清、口蹄疫亚洲1型阳性血清和A型阳性血清,固相竞争ELISA方法和液相阻断ELISA方法的特异性分别是95.5%,84.7%。固相竞争ELISA方法检测口蹄疫亚洲1型、口蹄疫A型阳性血清时,无交叉反应,O型口蹄疫病毒感染牛、免疫牛和感染猪血清的阳性检出率均为100%,免疫猪检出率为86.7%。 相似文献
122.
Jun-Sung Kim Kyeong Nam Yu Mi Suk Noh Min-Ah Woo Sung-Jin Park Jin Hong Park Jin Hua Hyun Sun Cho Soon Kyung Hwang Eun-Sun Lee Youn-Sun Chung In-Young Choi Se-Chang Kwon Myung-Haing Cho 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(1):45-50
Interferon (IFN) has therapeutic potential for a wide range of infectious and proliferative disorders. However, the half-life of IFN is too short to have a stable therapeutic effect. To overcome this problem, serum immunoglobulin has been fused to IFN. In this study, the efficacy of serum immunoglobulin fused INFs (si-IFN1 and si-IFN2) was evaluated on athymic mice bearing colon 26 adenocarcinoma cells. Seven days after the implantation of tumor cells, each group of mice was injected once a week with si-IFN1 and si-IFN2 at two different concentrations (10 × : 30 µg/kg and 50 × : 150 µg/kg). A slight anti-tumoral effect was observed in all 10 × groups compared to the control. In the 50 × groups, however, si-IFN1 and si-IFN2 showed significant anti- tumoral effects compared to the control. To gain more information on the mechanisms associated with the decrease of tumor size, a Western blot assay of apoptosis-related molecules was performed. The protein expression of cytochrome c, caspase 9, 6, and 3 were increased by si-IFN1 and si-IFN2. These 2 IFNs also increased the expressions of p53, p21, Bax and Bad. Interestingly, si-IFN1 and si-IFN2 decreased the expression of VEGF-β. Taken together, serum immunoglobulin fused IFNs increased therapeutic efficacy under current experimental condition. 相似文献
123.
Xiaodong Zhang Liang Zhang Jinnan Shang Qiangqiang Tao Mi Tian Yingchun Ma Yiliang Xu Yueyun Ding Rong Zhou Kui Li Zongjun Yin 《Reproduction in domestic animals》2019,54(7):1018-1025
The aim of this study was to explore the expression difference of miRNAs and mRNAs between the follicular phase (FP) and luteal phase (LP) in porcine ovaries and provide a theoretical basis for the research on mammalian reproductive regulation. RNA‐Seq and miRNA‐Seq were used to identify differentially expressed genes (DEGs) and miRNAs (DEMs) between the FP and LP in ovaries of six sows (3‐year‐old Yorkshire pigs with similar weights and same parities). Bioinformatic analysis was used to screen potential genes and miRNAs related to porcine ovarian function. Real‐time qualitative PCR was used to validate the sequencing results. RNA‐Seq results showed that 3,078 genes were up‐regulated, and 1,444 genes were down‐regulated in the LP compared with the FP, and DEGs were significantly enriched in 242 Gene Ontology (GO) terms and 33 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. miRNA‐Seq identified 112 DEMs, of which 25 were up‐regulated and 87 were down‐regulated in the LP compared with the FP. We obtained 186 intersection genes (IGs) between the 4,522 DEGs and 2,444 target genes predicted from the 112 DEMs. After constructing a miRNA‐gene‐pathway network, we identified key miRNAs and genes including miR‐17‐3p, miR‐214, miR‐221‐5p, miR‐125b, FGF1, YWHAG, YWHAZ, FDFT1 and DHCR24, which are enriched in Hippo and PI3K‐Akt signalling pathways, and various metabolic pathways. These results indicate that these key genes and miRNAs may play important roles in the developmental transition from FP to LP in porcine ovaries and represent candidate targets for further study. 相似文献
124.
新疆药桑黄酮和多酚的提取与分析研究初报 总被引:5,自引:0,他引:5
本文采用有机溶剂提取技术和分光光度法.对新疆药桑桑果、叶片和枝条等不同器官的黄酮、多酚类化合物进行提取和测试分析,研究结果表明:新疆药桑同一株树体桑果、叶片和枝条等不同器官间的黄酮和多酚类化合物的含量存在着显著差异,其中叶片黄酮和多酚类含量最高、枝条次之、桑果中最低;研究目的为新疆药桑桑叶,桑枝,桑椹的药用功效机理研究和开发利用提供理论依据。 相似文献
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126.
Silvia Kohutova Michaela Paninarova Miša Škorič Vladimir Jekl Zdenek Knotek Karel Hauptman 《Journal of Exotic Pet Medicine》2018,27(1):41-45
A 3-year-old, 920 g intact female guinea pig presented with a 4-month history of nonpruritic hair loss on the ventral abdomen. The physical examination revealed flank and ventral abdominal alopecia, mucoid vulvar discharge, and abdominal distension. Bilateral rounded masses just caudal to the kidneys and structures consistent with enlarged uterine horns were detected on abdominal palpation. Abdominal ultrasound revealed bilateral ovarian cysts, thickened uterine horns, and multiple circular hypoechoic and anechoic structures in the uterine wall. The patient underwent ovariohysterectomy. Gross examination of the uterus revealed a piece of hay in the left uterine horn. A final diagnosis was hormonally active ovarian follicular cysts, cystic endometrial hyperplasia, and purulent bacterial endometritis caused by Escherichia coli, Fusobacterium nucleatum, and Arthrobacter spp. Cystic endometrial hyperplasia is infrequently reported in guinea pigs, and this report describes an associated bacterial endometritis and uterine foreign body with concurrent ovarian cysts. 相似文献
127.
玉米细胞系中期染色体的分离及其生化分析 总被引:3,自引:0,他引:3
用0.1%秋水仙素处理墨西哥黑甜玉米细胞系17小时,其有丝分裂中期指数(Met.I)可提高3~4倍,达15%左右。用低 pH(3.2~3.7)作稳定条件,根据分离 Hela 细胞系和哺乳动物细胞系中期染色体的方法加以综合和改进,发展了一种新的适于高等植物染色体的分离程序。所分离的染色体形态典型,纯度较好。用0.2N H_2SO_4抽提染色体组蛋白并进行聚丙烯酰胺凝胶电泳,结果表明,分离的染色体组蛋白完整。用0.2N H_2SO_4除去染色体组蛋白后,染色体形态无明显变化,说明中期染色体高级结构与组蛋白无关。本项研究还首次提供了高等植物染色体组分含量及其比例的参数。 相似文献
128.
转换光周期对春性小麦叶片数的影响 总被引:2,自引:0,他引:2
利用6个来自我国不同生态区的春性小麦品种,通过不同穗分化期转换光周期实验研究了小麦叶片数的变异规律。结果发现,如果二棱期以前一直处于长日照条件,则至二棱期时幼穗基部的叶原基数与最终叶片数相同,不再受以后的日照长度影响。相反,如果二棱期以前处于短日条件,则转入长日照后,最终叶片数少于二棱期时幼穗基部的叶原基数,其中光周期敏感品种平均下降2.13片,光周期不敏感品种平均下降0.56片。据此推测,当前期处于短日照时,二棱期幼穗基部已分化的叶原基中,仍有部分为不稳定叶原基,随以后光周期变化而发生转化,短日照下继续发展为叶片,长日照下则发生退化,继而从中分化小穗原基。 相似文献
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130.