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31.
WANG Huaqing GAO Qingshan JIANG Wenjie ZHAO Yuhan JIN Qingguo LI Yinghua XU Yongnan 《中国畜牧兽医》2019,46(2):497-503
To investigate the effect of histone deacetylation inhibitor Psammaplin A (PsA) on the development of bovine aging oocytes in vitro,oocytes were randomly divided into control group,aging group and 50 mmol/L PsA treated aging group (PsA group).Immunofluorescence staining and JC-1 were used to detect the blastocyst rate of bovine oocytes after parthenogenetic activation,the number of cells in blastocysts,apoptosis,reactive oxygen species (ROS),glutathione (GSH) and mitochondrial membrane potential intensity of embryos.The results showed that the blastocyst rate of the aging group was significantly lower than that of PsA and control groups (P<0.05).The blastocyst rate of PsA group was not significantly different from that of control group (P>0.05).The number of cells in the blastocysts of control group and PsA group were significantly higher than that of aging group (P<0.05).The number of cells in the blastocysts of PsA group was not significantly different from that of control group (P>0.05).The apoptosis rate in aging group was significantly higher than that of control and PsA groups (P<0.05),the apoptosis rate of PsA group was significantly higher than that of control group (P<0.05).The GSH level of MⅡ oocytes in aging group was significantly lower than that of control and PsA groups (P<0.05).There was no significant difference in GSH level between control and PsA groups (P>0.05).The ROS level of the embryos in aging group was significantly higher than that of control and PsA groups (P<0.05).The ROS level in PsA group was significantly higher than that of control group (P<0.05).The mitochondrial membrane potential of early embryos of aging group 4-8 cells was significantly lower than that of control and PsA groups (P<0.05).The mitochondrial membrane potential intensity of control group was significantly higher than that of PsA group (P<0.05).In summary,PsA could effectively delay the aging of bovine oocytes and improve the quality of oocytes. 相似文献
32.
β-胡萝卜素羟化酶(beta-carotene hydroxylase,BCH)是植物类胡萝卜素合成代谢中的关键限速酶,为获得烟草β-胡萝卜素羟化酶2(NtBCH2)基因序列,采用同源克隆法从烟草中分离NtBCH2的基因组DNA序列,基因登录号为JX101477。结果表明:1)同源克隆法从烟草中克隆出NtBCH2基因,NtBCH2基因组DNA全长2131bp,cDNA为1 083bp,含7个外显子和6个内含子。2)NtBCH2蛋白有309个氨基酸,分子量为34.79kD,具有7个糖基化位点,11个磷酸化位点,4个跨膜域。3)系统发育树与BLAST分析表明,NtBCH2是番茄的SlBCH和辣椒CaBCH2的同源基因;GENEVESTIGATOR数据库芯片结果表明,NtBCH2在幼嫩的茎和子叶中表达量最高。 相似文献
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34.
Xinying Zhang Yajing Wang Guirong Huang Fu Feng Xiaoying Liu Rui Guo Fengxue Gu Xin Hu Ziguang Yang Xiuli Zhong Xurong Mei 《Journal of Agronomy and Crop Science》2020,206(2):161-168
Great understanding of the genotypic difference in diurnal stomatal conductance (gs) pattern and the key determinants of the pattern is important for saving water by adopting cultivars appropriately. Fifteen wheat genotypes were studied under different soil conditions and various meteorological conditions with pot cultivation in rain shelter for two years. Genotype and air humidity were found to be key determinants of diurnal gs pattern. All genotypes under low relative humidity (LRH) and most genotypes under high relative humidity (HRH) displayed a gradual decline pattern from morning through the afternoon. Under moderate relative humidity (MRH), all genotypes present a single-peak curve pattern, but they differed in peak time, which may lead to unreliable gs comparison between genotypes and get ostensible contrasting materials. The stomatal conductance was significantly different among genotypes under LRH and the increased gs magnitude is also significantly different when it was compared between LRH and HRH. The present results provide new thinking for selecting and adopting appropriate cultivars with specific stomata traits for the area with various meteorological conditions. 相似文献
35.
失地农民的再就业问题关系到农民失地后的生活保障和生活出路,长期以来一直是各级政府和理论界所关注的重点问题。在走访调查无锡市锡山区东港镇X社区的失地农民再就业情况的基础上,从政府、劳动力因素和社会因素3个方面探讨分析了无锡市锡山区失地农民再就业的影响因素。 相似文献
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37.
玉米DDGS中抗生素残留的潜在风险及其检测方法 总被引:1,自引:0,他引:1
本文就DDGS产品中抗生素残留风险及其检测方法作一综述。 相似文献
38.
Haibo Wen Ruobo Gu Zheming Cao Xin Zhou Zhijuan Nie Xianping Ge Pao Xu Xin Zhou Zhijuan Nie Xianping Ge Pao Xu Dan Hua 《Journal of the World Aquaculture Society》2013,44(1):154-160
The variation and inheritance of juvenile shell color and pigmentation pattern in the freshwater mussel, Hyriopsis cumingii, were reported in 1‐yr‐old progeny of eight families. There were three distinctive phenotypes of shell color and pigmentation patterns observed, including a greenish‐brown shell with radial rays, yellowish‐brown shell with radial rays, and yellowish‐brown shell without radial rays. There were no greenish‐brown individuals without radial rays. The shell color phenotypes showed variation with the growth in juvenile Stage I (1–3 cm in shell length), and the percentage of individuals with radial rays increased once they reached a shell length of 11 mm and then stabilized after reaching 20 mm in shell length. Shell color differentiation became more apparent at a shell length of 26 mm. Results of chi‐square tests of the segregation ratio of shell color or ray phenotypes obtained from eight families at juvenile Stage II (6–9 cm in shell length) suggested that greenish‐brown is controlled by a dominant allele (G) and yellowish‐brown‐shell phenotype is by a recessive allele (y); the ray pattern phenotype is controlled by a recessive (r) and a dominant allele (R) at a single locus. Shell color phenotypes may be a useful genetic marker for future selective breeding of triangle pearl mussels. 相似文献
39.
为获得商品化非洲猪瘟病毒(ASFV)荧光PCR检测试剂盒的敏感性、特异性、一致性和最低检测限等试验数据,以世界动物卫生组织(OIE)推荐引物探针为金标准,以62份已灭活的ASFV阳性田间样品、32份阴性田间样品和P72基因核酸标准物质为检测对象,对农业农村部公布许可的其中17个厂家生产的商品化ASFV荧光PCR检测试剂盒开展了试验特性方面的比对研究。结果显示,17个厂家生产试剂盒的敏感性最低为77.4%,最高为96.8%,特异性最低为87.5%,最高为96.8%,均未达到100%,且有一定差别;12个厂家的试剂盒与OIE推荐引物探针检测结果一致性较好(Kappa值≥0.75),其余5个厂家的试剂盒与其一致性一般(0.4Kappa值0.75);17个厂家的试剂盒均可检测到的最低稀释度为5.9×10~3×2~(-3)拷贝/μL,但不同厂家试剂盒的最低检测限有所差别,其中5个试剂盒可检测到的最低稀释度为5.9×10~3×2~(-3)拷贝/μL,2个试剂盒为5.9×10~3×2~(-4)拷贝/μL,6个试剂盒为5.9×10~3×2~(-5)拷贝/μL,3个试剂盒为5.9×10~3×2~(-6)拷贝/μL,1个试剂盒至少为5.9×10~3×2~(-7),且大部分国产试剂盒的最低检测限比进口试剂盒低。本研究为ASFV荧光PCR检测试剂盒的筛选和比对提供了参考数据。 相似文献
40.
2018年8月开始,非洲猪瘟在我国快速多点发生,该病是高度接触性传染性疾病,目前无有效的疫苗和药物控制,各大公司和养殖户开始了猪场生物安全体系的升级改造。两年后我国大部分猪场的成功复产,全国生猪出栏量的大幅提升,证明了生物安全措施巨大效力;同时在严格的生物安全措施下创新了精准剔除、快速复产等操作,进一步证明了生物安全措施的有效作用。文章主要介绍猪场生物安全体系中入口(大门)和出口(后门)最为关键防线处的通道设计,方便所有的生物安全操作能够高效落实,切断病原轻易进出猪场的途径。 相似文献