首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   61篇
  免费   1篇
林业   5篇
农学   1篇
  3篇
综合类   9篇
畜牧兽医   31篇
园艺   12篇
植物保护   1篇
  2020年   4篇
  2019年   5篇
  2018年   3篇
  2017年   3篇
  2016年   2篇
  2015年   2篇
  2014年   6篇
  2012年   1篇
  2011年   1篇
  2010年   1篇
  2009年   1篇
  2008年   4篇
  2007年   4篇
  2006年   6篇
  2005年   3篇
  2004年   3篇
  2003年   3篇
  2001年   5篇
  2000年   1篇
  1999年   1篇
  1998年   3篇
排序方式: 共有62条查询结果,搜索用时 31 毫秒
1.
哺乳动物性别决定机理及性别鉴定方法研究进展   总被引:7,自引:0,他引:7  
哺乳动物的性别决定是由SRY基因为调控中心、多基因参与的级联调控过程。本文综述了性别决定基因及其功能、性别决定的分子模型及性别鉴定的方法等方面的研究进展。  相似文献   
2.
哺乳动物卵母细胞发育机理的研究进展   总被引:3,自引:1,他引:2  
卵母细胞的成熟过程是一个复杂的减数分裂过程,许多分子参与了这个过程的调控,本文就卵母细胞成熟抑制因子(OMI)、成熟促进因子(MPF)、生长分化因子(GDF)、微管辅助蛋白(MAP)、激素、Ca^2 及钙调素等对卵母细胞发育调控机理作一综述。  相似文献   
3.
哺乳动物原始生殖细胞与EG细胞研究进展   总被引:1,自引:0,他引:1  
本文综述了哺乳动物原始生殖细胞的来源、增殖、迁移及生物学特点及近年来国内外用原始生殖细胞分离EG细胞的研究进展,探讨了EG细胞作为另一种多能性干细胞的优越性。  相似文献   
4.
AIM:To study the influence of Raptor on the invasion ability of glioma cells. METHODS:The technique of RNA interference was used. U87 cells were transfected with Raptor restricted siRNA plasmid, and the expression level of Raptor in the transfected cells was detected by Western blotting. The invasive ability of the cancer cells in vitro was determined. The phosphorylation level of ARK5 and the expression of MMP-2 and MMP-9 were detected by Western blotting. The expression levels of Raptor in the tumor samples of low-grade gliomas (WTO grade I and grade II) and high-grade gliomas (WTO grade III and grade IV) were also analyzed by immunohistochemical staining. RESULTS:Raptor siRNA was transfected into U87 cells and the cells were named siRaptor/U87 cells. The cells transfected with the control plasmid was named Scr/U87 cells. The expression level of Raptor in siRaptor/U87 cells was lower than that in Scr/U87 cells. The results of in vitro invasion assay showed that the number of siRaptor/U87 cells penetrating the Matrivgel matrix membrane was less than that of Scr/U87 cells (P<0.01). The protein expression of MMP-2 and MMP-9, and phosphorylation of ARK5 protein in the cells in the experimental group were lower than those in control group. The correlation between the expression of Raptor in gliomas and the degree of deterioration was also observed (P<0.01). CONCLUSION:The expression of Raptor may contribute to the invasion ability of glioma cells by phosphorylation of ARK5 and increase in the levels of MMP-2 and MMP-9.  相似文献   
5.
哺乳动物的有色毛表型要受黑色素皮质素受体1(Melanocortin Receptor1,MC 1 R)位点的不同等位基因调节。MC1R基因的变异与动物的皮毛、人的皮肤和头发颜色差异密切相关。本文对该基因的定位、突变、多态检测及黑色素皮质素受体的作用机制进行了综述。  相似文献   
6.
AIM: To investigate the inhibitory effect of CC-223, an inhibitor of mammalian target of rapamycin (mTOR) kinase, on the viability of human breast cancer cells and its mechanism. METHODS: The inhibitory effect of CC-223 on the viability of MCF-7 cells and MDA-MB-231 cells was measured by CCK-8 assay. The cell cycle distribution of breast cancer cells was examined by flow cytometry. The expression of cell cycle-related proteins and oncoproteins c-Myc and survivin was analyzed by Western blot. RESULTS: CC-223 significantly inhibited the viability of both MCF-7 and MDA-MB-231 cells (P<0.05). CC-223 induced cell cycle arrest in both G1 phase and G2/M phase in the MCF-7 cells (P<0.05). However, low concentration of CC-223 treatment resulted in the accumulation of MDA-MB-231 cell cycle in the G2/M phase, and the cell number in G1 phase was unaffected. Treatment with CC-223 for 24 h clearly inhibited the protein levels of cyclin B1, cyclin D1 and phosphorylated cell division cycle protein 2 in the breast cancer cells (P<0.05). CC-223 suppressed the expression of c-Myc and survivin in both MCF-7 cells and MDA-MB-231 cells (P<0.05). CONCLUSION: CC-223 inhibits cell viability by blocking cell cycle progression and down-regulating expression of c-Myc and survivin in both MCF-7 and MDA-MB-231 cells.  相似文献   
7.
哈纳斯自然保护区兽类区系与分布特征   总被引:3,自引:1,他引:2  
本文以阿勒泰地区哈纳斯国家级自然保护区兽类为主,初步分析了其在调查区各生态地理单元中的组成,分布特点和区系成份等。  相似文献   
8.
运用主成分分析与人工神经网络相结合的方法预测哺乳动物蛋白质氧链糖基化位点。以各种窗口长度(N=5,7,9,11,21,31,41,51)的哺乳动物蛋白质序列为研究对象,首先分析蛋白质序列的结构特点,以主成分分析法(PCA)提取主成分,降低样本向量的维数,消除样本向量各分量之间的相关性;然后用一个含单隐层并且输出层只有一个神经元的BP神经网络对氧链糖基化位点进行预测,以确定蛋白质序列中的丝氨酸残基或苏氨酸残基是否糖基化;最后用Matthews相关系数对预测结果进行评价。结果表明:①糖基化蛋白质中P、S、T和A的含量比非糖基化蛋白质中的含量高,S在N端和C端附近都易糖基化,而T在N端附近易糖基化;②提出的预测方法准确快速,预测准确率达65%~92.5%,Matthews相关系数在0.35~0.73之间。  相似文献   
9.
Sodium-coupled neutral amino acid transporter 2 (SNAT2), also known as solute carrier family 38 member 2 (SLC38A2), is expressed in the skeletal muscle. Our research previously indicated that SNAT2 mRNA expression level in the skeletal muscle was modulated by genotype and dietary protein. The aim of this study was to investigate the key role of the amino acid transporter SNAT2 in muscle cell growth, differentiation, and related signaling pathways via SNAT2 suppression using the inhibitor α-methylaminoisobutyric acid (MeAIB). The results showed that SNAT2 suppression down-regulated both the mRNA and protein expression levels of SNAT2 in C2C12 cells, inhibited cell viability and differentiation of the cell, and regulated the cell distribution in G0/G1 and S phases (P < 0.05). Meanwhile, most of the intercellular amino acid content of the cells after MeAIB co-culturing was significantly lower (P < 0.05). Furthermore, the mRNA expression levels of system L amino acid transporter 1 (LAT1), silent information regulator 1, and peroxisome proliferator-activated receptor-gamma co-activator 1 alpha, as well as the protein expression levels of amino acid transporters LAT1 and vacuolar protein sorting 34, were all down-regulated. The phosphorylated protein expression levels of mammalian target of rapamycin (mTOR), regulatory-associated protein of mTOR, 4E binding protein 1, and ribosomal protein S6 kinase 1 after MeAIB treatment were also significantly down-regulated (P < 0.05), which could contribute to the importance of SNAT2 in amino acid transportation and skeletal muscle cell sensing. In conclusion, SNAT2 suppression inhibited C2C12 cell growth and differentiation, as well as the availability of free amino acids. Although the mTOR complex 1 signaling pathway was found to be involved, its response to different nutrients requires further study.  相似文献   
10.
To study complement function in mammalian leishmanioses, we developed mouse monoclonal antibodies to the human complement system components C1q, C4, factor D, factor H, factor B, properdin, C5 and C9. Antibody specificity was determined by indirect and capture ELISA and by Western blot. In flow cytometry analysis, seven antibodies recognized the cognate component on human serum-opsonized Leishmania promastigotes. Antibody reactivity was screened against promastigotes opsonized with sera of nine mammalian genera: pig, guinea pig, goat, rabbit, cat, dog, hamster, jird and rat. No antibody recognized jird epitopes on promastigotes. Anti-C4, -properdin, and -C5b reacted with the orthologous protein of all other mammals tested except cat (anti-properdin) and hamster (anti-C5b); anti-C9 only recognized the rabbit ortholog, and anti-C1q, -factor B and -factor H did not react with any of the nine orthologs. Such interspecies crossreactive antibodies can be valuable tools for analysis of mammalian complement function in infectious diseases.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号