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1.
哺乳动物体细胞克隆研究进展 总被引:3,自引:0,他引:3
哺乳动物体细胞克隆技术是近年来才发展起来的技术,但体细胞克隆绵羊-多利的诞生却引起了世界轰动,充分显示了其重在的科学研究价值和潜在的应用价值。本文对哺乳动物体细胞克隆技术研究现状,理论基础研究,应用等方面作一综述。 相似文献
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生殖细胞从未成熟阶段发育到成熟阶段有2个主要的细胞命运决定:进行减数分裂时间的决定和分化为精子还是卵子的决定,这2个决定是密切偶联的。主要阐述了哺乳动物生殖细胞性别决定的分子机制以及减数分裂在生殖细胞性别决定中的作用机制。 相似文献
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EGF在哺乳动物卵母细胞体外受精中的作用 总被引:1,自引:1,他引:0
[目的]为卵母细胞的生长发育创造更加适宜的环境。[方法]对EGF的理化特性、作用机理及其在卵母细胞体外培养、体外受精和早期胚胎发育中的作用进行阐述。[结果]EGF、IGF和TGF等生长因子在哺乳动物卵母细胞体外培养中起很重要的作用,尤其是在无血清培养条件下。生长因子可大大提高卵母细胞的成熟率和受精率,并对受精卵的发育有很大的促进作用。在众多生长因子中研究的最多的就是EGF。EGF能够促进卵母细胞减数分裂、卵丘细胞扩散,调节卵母细胞胞质成熟。[结论]对EGF的深入研究对于提高哺乳动物卵子的体外成熟率、体外受精率以及胎儿的发育都具有重大意义,为体外受精等技术和胚胎工程的发展提高可靠的保障。但对清楚了解EGF及其受体的性质和作用机制仍存在很多问题,且对表皮生长因子对体外受精的作用研究较少。 相似文献
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回顾哺乳动物(牛、羊、猪、小鼠、大鼠、兔以及仓鼠等)腔前卵泡的研究历史和现状并探讨腔前卵泡研究在珍稀濒危野生动物(猫科动物、犬科动物和灵长类动物等)上应用的可能性. 相似文献
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Andrew W. Claridge Ross B. Cunningham Peter C. Catling Allan M. Reid 《Forest Ecology and Management》2010
The relative activity of ground-dwelling vertebrates was monitored using tracks in sand plots for 10 consecutive years across three nearby study areas in south-eastern mainland Australia. Two areas were subject to intensive 1080 poison baiting for foxes, while one unbaited area acted as a control. At the two 1080 baited sites there was a demonstrable decline in the reporting rate of fox tracks, while that of feral cats also declined concomitantly. In contrast, the reporting rate of wild dog tracks did not change. At the unbaited site the reporting rate of wild dog tracks increased slightly, while that of foxes remained stable and that of feral cats declined slightly. Prevailing ecological theory would suggest that in systems where larger predators are reduced in activity or abundance, smaller predators should increase. This was not the case in our work. Instead, while the larger sized fox has decreased at baited sites, the smaller sized cat has declined at a regional scale, in all likelihood against a backdrop of long-term drought and diminished prey resources. Among the native omnivorous mammals that ordinarily fall prey to foxes, bandicoots, brushtail possums and lyrebirds increased in activity against a background of diminishing fox activity, although these effects were not uniform at both baited sites. In contrast, at the study area where foxes were not baited, the activity of bandicoots, brushtail possums and lyrebirds either did not change or diminished. Trends in the activity levels of these animals, particularly bandicoots, may have been moderated in part by prevailing rainfall conditions. Otherwise, habitat complexity may also help regulate activity patterns. Land managers concerned with preserving and enhancing biodiversity need to not only focus on the baiting of introduced predators but also be mindful of habitat condition and the effects of climate. 相似文献
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