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101.
支持细胞对维持精子形成过程中的微环境起决定作用,它可以通过分泌功能、细胞间连接形成的血睾屏障功能以及吞噬功能等来促进精子的形成过程,其发育异常会导致不同程度的雄性生殖缺陷。基于支持细胞在雄性动物生殖过程中的作用,体外培养高纯度支持细胞可成为研究睾丸两大核心功能-精子发生和性激素分泌功能相关调节机制重要的细胞模型。此外,体外培养睾丸支持细胞也可作为生殖毒理学等新兴热点领域的细胞模型,为评估和研究环境因素对雄性生殖的影响提供便利。因此,作者系统地归纳、总结了目前关于动物支持细胞生物功能的研究及常用的体外分离纯化、培养及鉴定方法,以期为利用动物支持细胞开展雄性生殖领域的研究提供参考。  相似文献   
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动物产品作为日常饮食结构的重要组成内容,直接关乎人民健康和社会安定,因此动物卫生监督工作责任重大。动物卫生监督作为农业综合执法的一项基本工作内容,在执法改革过程中仍有许多问题制约着动物卫生监督工作的有效开展。该文从执法力量、职责划分、兽医数量、专业水平、执法环境和市场监管6个方面分析动物卫生监督工作中的不足,并提出对策。  相似文献   
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随着计算机的普及,特别是软件技术的发展,基于电脑控制且充分展示个性化创新实验,成为当今高等学校素质教育的重要方式和发展方向。为此,详细介绍了德国慧鱼公司的专利产品“创意组合模型(fischertechnik)的应用实例。结合LLWin3.0图形化编程技术。为教育行业应用提供了有效的途径。  相似文献   
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The study was aimed to explore the protective effect of sulforaphane (SFN) on the reproductive function of male mice with cadmium poisoning.40 healthy clean grade male Kunming mice were randomly divided into four groups:control group (H2O),cadmium chloride group (2.3 mg/kg CdCl2),sulforaphane group (10 mg/kg SFN),sulforaphane + cadmium chloride group (10 mg/kg SFN+2.3 mg/kg CdCl2),and continuous administration for 10 d,all mice were executed by dislocated cervical vertebra at 2 d after the last administration,and then the pathologic changes of testicular tissues,organ coefficient of testicle and epididymis,sperm quality and concentration of testosterone were tested.Additionally,the contents of GSH and MDA,and the activities of T-SOD in testis were also detected at the same time. Compared with the control group,pathology damages were observed in cadmium chloride group,organ coefficient of testis and epididymis,sperm quality and levels of testosterone extremely significantly decreased (P<0.01),the activities of T-SOD and GSH content were extremely significantly decreased (P<0.01),and the concentration of MDA was extremely significantly enhanced (P<0.01).Compared with the control group,the activity of T-SOD and concentration of GSH in sulforaphane group were significantly increased (P<0.05),and the concentration of MDA was not significant different between the control group and sulforaphane group (P>0.05).While compared with the cadmium chloride group,the sperm motility rate and sperm total count in sulforaphane and cadmium chloride group were extremely significantly increased (P<0.01),the organ coefficient of testicle and epididymis was increased significantly (P<0.05),the concentration of GSH and activity of T-SOD in testicular tissue were extremely significantly increased (P<0.01),and the concentration of MDA was extremely significantly decreased (P<0.01).The results indicated that sulforaphane had the protection effect on reproduction function of male mice with cadmium poisoning.  相似文献   
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This study compared the productive and nutritional parameters of milk from crossbred lactating cows managed on Panicum maximum Jacq. cv. Tanzania and with a diet supplemented with different pressed oilseed cakes. The supplements used were as follows: peanut cake, sunflower cake and palm kernel cake for replacement of soybean meal. Sixteen cows with an average weight of 544 ± 57 kg and producing 8 ± 1.4 L of milk per day were used in this study. The animals were randomly assigned to the treatments according to a Latin square design repeated over time, with four treatments, 16 animals and four experimental periods. Supplementation of the diet with peanut cake, sunflower cake and palm kernel cake compared with soybean meal in the diet of cows did not affect the average daily production or composition of the milk. The palm kernel cake promoted an increase in lauric fatty acids (C12:0) and palmitoleic acids (C16:1) (5.02 and 1.65%, respectively) compared with peanut cake and sunflower cake (4.13 and 4.01%, respectively). The levels of oleic fatty acids (C18:1) were higher for the sunflower cake and palm kernel cake supplements (26.01 and 25.01%, respectively) compared with peanut cake (23.11%). The replacement of soybean meal with sunflower cake and palm kernel cake improved the nutritional quality of the milk, with lower concentrations of saturated fatty acids and higher concentrations of unsaturated fatty acids, without compromising the production or nutritional composition of the milk. © 2015 Japanese Society of Animal Science  相似文献   
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