全文获取类型
收费全文 | 372篇 |
免费 | 2篇 |
国内免费 | 2篇 |
专业分类
系统科学 | 7篇 |
教育与普及 | 3篇 |
理论与方法论 | 2篇 |
现状及发展 | 97篇 |
研究方法 | 35篇 |
综合类 | 228篇 |
自然研究 | 4篇 |
出版年
2017年 | 3篇 |
2016年 | 2篇 |
2013年 | 5篇 |
2012年 | 25篇 |
2011年 | 33篇 |
2010年 | 9篇 |
2009年 | 6篇 |
2008年 | 17篇 |
2007年 | 20篇 |
2006年 | 21篇 |
2005年 | 12篇 |
2004年 | 20篇 |
2003年 | 14篇 |
2002年 | 21篇 |
2001年 | 9篇 |
2000年 | 7篇 |
1999年 | 7篇 |
1994年 | 3篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1990年 | 6篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1980年 | 4篇 |
1979年 | 6篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1976年 | 5篇 |
1975年 | 7篇 |
1974年 | 7篇 |
1973年 | 4篇 |
1972年 | 3篇 |
1971年 | 7篇 |
1970年 | 7篇 |
1969年 | 4篇 |
1968年 | 2篇 |
1967年 | 2篇 |
1966年 | 7篇 |
1965年 | 4篇 |
1964年 | 2篇 |
1963年 | 2篇 |
1960年 | 2篇 |
1958年 | 2篇 |
1955年 | 1篇 |
1946年 | 1篇 |
排序方式: 共有376条查询结果,搜索用时 827 毫秒
111.
J. Gillman Christine Gilbert Isobel Spence 《Cellular and molecular life sciences : CMLS》1955,11(4):157-158
Zusammenfassung Die Entstehung von Reticulosarkom bei Ratten nach mehrmaliger Injektion von Trypanblau kann unterdrückt werden durch Entkräftung, Verabreichung anti-thyreoidaler Mittel und durch alle andern Faktoren, welche den Stoffwechsel herabsetzen. 相似文献
112.
Zusammenfassung Extraktstoffe vonH. cecropia, S. cynthia undR. orizaba zeigten antibakterielle Wirkung gegenüber mehreren Mikroorganismen. Ein schwächerer Effekt wurde auch mit den Extraktstoffen vonGalleria mellonella, adulten Männchen vonCynthia- und vonCecropia-Puppen beobachtet. Die antimikrobielle Aktivität wurde mit dem Fettsäureanteil der Extraktstoffe in Beziehung gesetzt und von der Wirkung des Juvenilhormons abgegrenzt.
Supported by Grants G-7597 from NSF and A-2818 from U.S.P.H.S. 相似文献
Supported by Grants G-7597 from NSF and A-2818 from U.S.P.H.S. 相似文献
113.
Cross partition and isoelectric points of proteins 总被引:3,自引:0,他引:3
114.
Gene regulation: reviving the message 总被引:2,自引:0,他引:2
115.
Recruitment and regulation of phosphatidylinositol phosphate kinase type 1 gamma by the FERM domain of talin 总被引:11,自引:0,他引:11
Di Paolo G Pellegrini L Letinic K Cestra G Zoncu R Voronov S Chang S Guo J Wenk MR De Camilli P 《Nature》2002,420(6911):85-89
Membrane phosphoinositides control a variety of cellular processes through the recruitment and/or regulation of cytosolic proteins. One mechanism ensuring spatial specificity in phosphoinositide signalling is the targeting of enzymes that mediate their metabolism to specific subcellular sites. Phosphatidylinositol phosphate kinase type 1 gamma (PtdInsPKI gamma) is a phosphatidylinositol-4-phosphate 5-kinase that is expressed at high levels in brain, and is concentrated at synapses. Here we show that the predominant brain splice variant of PtdInsPKI gamma (PtdInsPKI gamma-90) binds, by means of a short carboxy-terminal peptide, to the FERM domain of talin, and is strongly activated by this interaction. Talin, a principal component of focal adhesion plaques, is also present at synapses. PtdInsPKI gamma-90 is expressed in non-neuronal cells, albeit at much lower levels than in neurons, and is concentrated at focal adhesion plaques, where phosphatidylinositol-4,5-bisphosphate has an important regulatory role. Overexpression of PtdInsPKI gamma-90, or expression of its C-terminal domain, disrupts focal adhesion plaques, probably by local disruption of normal phosphoinositide balance. These findings define an interaction that has a regulatory role in cell adhesion and suggest new similarities between molecular interactions underlying synaptic junctions and general mechanisms of cell adhesion. 相似文献
116.
117.
Morrish TA Gilbert N Myers JS Vincent BJ Stamato TD Taccioli GE Batzer MA Moran JV 《Nature genetics》2002,31(2):159-165
118.
A Rad26-Def1 complex coordinates repair and RNA pol II proteolysis in response to DNA damage 总被引:11,自引:0,他引:11
Woudstra EC Gilbert C Fellows J Jansen L Brouwer J Erdjument-Bromage H Tempst P Svejstrup JQ 《Nature》2002,415(6874):929-933
119.
Most mitochondrial proteins are synthesized on cytoplasmic ribosomes and imported into mitochondria. The imported proteins are directed to one of four submitochondrial compartments--the outer mitochondrial membrane, the inner mitochondrial membrane, the intramembraneous space, or the matrix--where the protein then functions. Here we show that the steroidogenic acute regulatory protein (StAR), a mitochondrial protein required for stress responses, reproduction, and sexual differentiation of male fetuses, exerts its activity transiently at the outer mitochondrial membrane rather than at its final resting place in the matrix. We also show that its residence time at this outer membrane and its activity are regulated by its speed of mitochondrial import. This may be the first example of a mitochondrial protein exerting its biological activity in a compartment other than that to which it is finally targeted. This system enables steroidogenic cells to initiate and terminate massive levels of steroidogenesis within a few minutes, permitting the rapid regulation of serum steroid hormone concentrations. 相似文献
120.
Reciprocity, whether direct or indirect, is thought to be the key to establishing cooperation among non-relatives. But Riolo et al. have presented a model in which cooperation is instead based on similarity: agents donate only when their partner's 'tag' lies within a 'tolerance' range around their own. Here we point out that their model requires individuals with identical tags to cooperate with each other, and show that cooperation tends to collapse when individuals bearing identical tags are given the option of not donating. We therefore question their mechanism for maintaining cooperation without reciprocity. 相似文献