全文获取类型
收费全文 | 247篇 |
免费 | 8篇 |
出版年
2018年 | 1篇 |
2016年 | 1篇 |
2015年 | 6篇 |
2014年 | 6篇 |
2013年 | 26篇 |
2012年 | 5篇 |
2011年 | 16篇 |
2010年 | 6篇 |
2009年 | 7篇 |
2008年 | 13篇 |
2007年 | 6篇 |
2006年 | 23篇 |
2005年 | 19篇 |
2004年 | 14篇 |
2003年 | 15篇 |
2002年 | 16篇 |
2001年 | 3篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1993年 | 4篇 |
1992年 | 2篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1971年 | 1篇 |
排序方式: 共有255条查询结果,搜索用时 0 毫秒
251.
Membrane alterations accompanying in vitro capacitation of hamster spermatozoa were examined using the freeze-fracture technique with or without use of filipin, a sterol-binding probe. In the spermatozoa prior to or at 10 min after start of incubation in capacitating medium, large (about 11 nm) and small (8–9 nm) intramembranous particles (IMPs) were present in the periacrosomal region of the sperm plasma membrane (PAPM). Filipin sterol complexes (FSCs) were densely (about 500/μ2) distributed in the PAPM prior to incubation. The density of FSCs in the PAPM was reduced by 70–80% of the original density by 2 hr of incubation. At the same time, small patches of IMP-free areas appeared in the plasma membrane above the equatorial and middle segments of the acrosome. By the end of 3 hr of incubation, the majority of small IMPs had disappeared from the PAPM. Remaining large and small IMPs tended to aggregate in the PAPM. During incubation in capacitation medium, “cords,” or linear arrangements of closely packed IMPs, appeared near the posterior ring of the sperm head. These observations strongly suggest that the acrosome reaction of the hamster spermatozoa is preceded by the removal (deletion) of filipin-reactive sterols (FRSs) and the disappearance of small IMPs from the lipid bilayer of PAPM. 相似文献
252.
253.
254.
Garth L. Nicolson Adele B. Brodginski Gillian Beattie Ryuzo Yanagimachi 《Molecular reproduction and development》1979,2(2):153-162
Differences in the exposure of spermatozoa surface components during epididymal passage have been examined using lactoperoxidase-catalyzed 125I-iodination or labeling with 125I-diazodiiodosulfanilic acid. Labeled surface proteins obtained from caput and cauda epididymides were solubilized in detergent, separated by sodium dodecylsulfate polyacrylamide slab gel electrophoresis, and identified by radiography. Densitometer scans of autoradiograms revealed increased amounts or exposures of surface proteins of ~35,000, ~39,000, ~50,000, and ~78,000 molecular weight on the cauda epididymal spermatozoa. 相似文献
255.