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排序方式: 共有225条查询结果,搜索用时 31 毫秒
51.
ZHOU Wen-ting SUN Long-fei YIN Na DU Shan-shan ZHAO Xin DAI Xiao-li LU Feng-hua SHI De-shun 《中国畜牧兽医》2016,43(11):2997-3002
In order to investigate the expression pattern of C-type natriuretic peptide(CNP)and its receptors(NPR)in buffalo follicles,firstly,the mRNA expression level of ANP,BNP,CNP,NPR1 and NPR2 in ovary were assayed by Real-time quantitative PCR;Secondly,the protein expression of CNP and NPR2 in buffalo follicles were detected by immunohistochemical stainning method;Lastly,the mRNA expression level of CNP and NPR2 in granule cells and cumulus cells were assayed by Real-time quantitative PCR.The results showed that CNP gene and its receptor NPR2 mainly expressed in buffalo ovary,the protein of CNP and NPR2 expressed in all stages of follicles,CNP mainly expressed in mural granulosa cells and NPR2 primarily presented in cumulus cells,the mRNA expression of CNP gene in granule cells was significantly higher than cumulus cells(P<0.05),whereas the mRNA expression of NPR2 gene in cumulus cells was significantly higher than granule cells(P<0.05).In conclusion,among the main members of natriuretic peptides and its receptors,CNP and NPR2 presented strong expression in buffalo ovary.CNP mainly expressed in mural granulosa cells,but NPR2 primarily presented in cumulus cells which arounding oocytes. 相似文献
52.
Paulina Puckowska Alicja Borowska Tomasz Szwaczkowski Kamil Oleski Stanislaw Kamiski 《Reproduction in domestic animals》2019,54(9):1163-1168
The aim of the study was to find functional polymorphism within two exons of the SIGLEC5 (sialic acid‐binding Ig‐like lectin‐5) gene and to examine its effects on the production and fertility traits of cows and bulls. Two hundred seventytwo Holstein‐Friesian cows and 574 bulls were included in the study. Novel missense polymorphism (A > G) within exon 3 causing substitution of amino acid arginine by glutamate in position 260 of SIGLEC5 protein (R260Q) was identified by sequencing and digestion by restriction enzyme Msp I. Basic production and fertility traits of cows and estimated breeding values (EBV) of bulls were analysed. The study demonstrated a significant association of SIGLEC5 R260Q polymorphism with days open and calving interval in cows as well as with breeding value for calving interval in bulls. An opposite effect of SIGLEC5 alleles for production and fertility traits was observed: the allele G increased the breeding value for the protein yield, while the allele A increased the breeding value for the calving interval. The current study suggests the involvement of SIGLEC5 R260Q polymorphism in biological processes related to fertility traits. This finding can be applied as a biomarker for a genetic improvement programme in Holstein‐Friesian cattle. 相似文献
53.
Marcelo HAF Mendes Maria HB Pinto Eduardo J Gimeno Claudio G Barbeito Fabiano JF de Sant'Ana 《Reproduction in domestic animals》2019,54(10):1366-1374
The lectin histochemical pattern (LHP) was characterized and compared in normal and cystic ovaries of sows. Six biotinylated lectins (PNA, SBA, WGA, RCA‐1, DBA and UEA‐1) were used on tissue sections. In the normal ovaries, the reaction to UEA‐1 and SBA was mild to moderate in mesothelial and endothelial cells. RCA‐1 staining was mild to moderate in theca interna of growing follicles, corpora luteum and mesothelium. In addition, this lectin presented strong reaction in endothelial cells, granulosa cells of atretic follicles, zona pellucida of growing follicles and plasma. DBA showed strong intensity in mesothelial and endothelial cells. There was mild to moderate reactivity to WGA in granulosa cells, corpus luteum and theca interna of follicles in development, and moderate in zona pellucida, in granulosa cells of atretic follicles and mesothelium. PNA staining was mild to moderate in oocytes and in the adventitia and media of medullary arteries. Changes in the LHP of the cystic ovaries were noted; however, there were no differences in these findings between the follicular and luteinized cysts. UEA‐1 reactivity in the cystic ovaries was moderately reduced in the mesothelial and endothelial cells, whereas there was mild reduction in the DBA staining in the granulosa cells. Reaction to RCA‐1 and WGA in the cysts also was decreased in theca interna, zona pellucida and granulosa cells of atretic follicles. Furthermore, endothelium and theca interna in the cystic ovaries presented mild reduction of marcation to SBA, whereas there was decreased reactivity to PNA in the oocytes and adventitia and media layers of the medullary arteries. The results of the current study show that cysts modify the LHP in swine ovaries. These changes of glycoconjugates in many ovarian structures could modify diverse process and may be one of the reasons for decreased fertility in sows. 相似文献
54.
疾病是影响畜牧业生产的主要因素,虽然传统的疾病控制方法对疾病的预防和治疗起到了重要作用,但随着分子生物学和基因工程技术的发展,分析在抗性和易感群体中候选基因的标记等位基因频率差异,结合遗传育种技术,提高家畜的抗病性与健康水平已成为当今提高家畜生产水平的重要途径。甘露糖结合凝集素(mannan-binding lectins,MBL)是构成人和动物血清补体凝集素途径的主要成分,在先天免疫过程中起重要作用。笔者简述了MBL的分布、结构、功能,介绍了MBL基因与抗病力的关系,对其作为家畜抗病育种遗传标记的应用前景进行了展望。期望MBL作为遗传标记,通过标记辅助选择进行抗病育种可以培育出抗病力强的家畜品种。 相似文献
55.
56.
Sadeghi A Broeders S De Greve H Hernalsteens JP Peumans WJ Van Damme EJ Smagghe G 《Pest management science》2007,63(12):1215-1223
BACKGROUND: To check for correlation between the insecticidal properties and the specificity of lectins, a comparative study was made of the insecticidal activities of two garlic lectins with different biological activities.RESULTS: The insecticidal activity of the garlic (Allium sativum L.) leaf lectin ASAL and bulb lectin ASAII towards the tobacco aphid Myzus nicotianae Blackman was studied using bioassays with transgenic tobacco (Nicotiana tabacum L. cv. Wisconsin 38). Bioassays were started with newborn nymphs of the tobacco aphid. Although during the first 7-8 days when nymphs developed to adults there were no apparent effects, part of the nymphal population was found to develop into winged (alate) forms. Later it became clear that transgenic plants expressing ASAL and ASAII had a significant effect on the reproduction capacity of the resulting adults, with a reduction of up to 40%. Different life table parameters such as prereproductive time, intrinsic rate of natural increase, generation time and doubling time were significantly affected (P < 0.05) in aphids grown on transgenic plant material expressing ASAL and ASAII.CONCLUSION: Bioassays with tobacco plants expressing ASAL and ASAII demonstrated a significant impact on the population growth of M. nicotianae. Therefore, both lectins can be considered as valuable candidate aphid control agents. 相似文献
57.
对野猪血清样品用溴化氰活化的甘露聚糖结合凝集素-Sepharose4B亲和柱亲和层析,获得纯化的野猪MBL样品,再进行SDS-PAGE电泳,显示有1条32kDa主带,2条36kDa和56kDa副带。选取32kDa的蛋白带制备免疫原,免疫家兔制备抗血清,Western blot方法鉴定该抗体可以特异性识别野猪血清中的MBL分子。本研究表明采用亲和层析法可以获得野猪血清中MBL-A分子,制备的多克隆抗体可以用于检测天然MBL分子,将为野猪MBL的生物学特性及与抗病力相关性的研究提供基础。 相似文献
58.
奥利亚罗非鱼3种C型溶菌酶基因的克隆及其序列分析 总被引:1,自引:0,他引:1
本研究结合RT-PCR和RACE法获得了奥利亚罗非鱼(Oreochromis aureus)三种C型溶菌酶基因C-1,-2和C-3的全长cDNA.3个基因的cDNA分别为581 bp、662 bp和695 bp,各编码143、156和143个氨基酸(GenBank accession No:EU913095,EU913094和EU836689),相互间氨基酸序列的同源性在63.9%~67.8%之间.3个基因均具有与其它物种C型溶菌酶相同的8个保守半胱氨酸残基和2个活性位点Glu~(35)和Asp~(52),可认为它们均为C型溶菌酶基因.在系统进化树中这3个基因首先与同属高等真骨鱼类的聚类,最后再与低等真骨鱼类的聚类,系统进化关系与传统鱼类分类地位相吻合,显示真骨鱼类C型溶菌酶的进化速度与物种的进化速度基本一致.蛋白分析软件分析显示这3个基因均具有C型溶菌酶的典型结构、相似的蛋白二、三级结构,推测应具有与C型溶菌酶相似的生理功能.但3个基因氨基酸序列间存在一定差异,其中C-1的等电点较低且碱性氨基酸较少,因此3种溶菌酶可能具有生理功能上的差异与分工. 相似文献
59.
60.
为探讨外源杀虫基因导入对棉花重要防御物质凝集素的影响,同时建立棉花凝集素的灵敏检测方法,采用血凝法检测转基因(Bt、CpTI和外源凝集素基因)棉花中凝集素的变化,并经胰蛋白酶处理鸡血红细胞、不同温度处理和比色法测定棉花的凝集素活性。结果表明,棉花叶片中凝集素水平随棉花生长而发生变化,不同外源基因的导入使棉花凝集活性升高或降低。采用经胰蛋白酶修饰后的鸡血红细胞检测,棉花凝集活性明显提高,最高是未经处理检测的64倍。棉花凝集素具有一定的抗热性,在45℃以下很稳定,但随温度的升高和处理时间的延长活性下降。血凝反应和比色法均能直观、定量地反映棉株中凝集素活性,但后者精度更高。以上研究结果表明,外源杀虫基因的导入引起棉花凝集素水平发生改变,比色法可以作为检测棉株中自身和外源凝集素基因表达后凝集活性的重要手段。 相似文献