全文获取类型
收费全文 | 769篇 |
免费 | 72篇 |
专业分类
841篇 |
出版年
2018年 | 5篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 20篇 |
2014年 | 26篇 |
2013年 | 36篇 |
2012年 | 34篇 |
2011年 | 54篇 |
2010年 | 18篇 |
2009年 | 21篇 |
2008年 | 27篇 |
2007年 | 27篇 |
2006年 | 22篇 |
2005年 | 24篇 |
2004年 | 33篇 |
2003年 | 35篇 |
2002年 | 24篇 |
2001年 | 14篇 |
2000年 | 22篇 |
1999年 | 20篇 |
1998年 | 15篇 |
1997年 | 8篇 |
1996年 | 9篇 |
1995年 | 9篇 |
1994年 | 10篇 |
1993年 | 8篇 |
1992年 | 8篇 |
1991年 | 9篇 |
1990年 | 12篇 |
1989年 | 16篇 |
1988年 | 12篇 |
1987年 | 9篇 |
1986年 | 11篇 |
1985年 | 11篇 |
1984年 | 20篇 |
1983年 | 10篇 |
1982年 | 13篇 |
1981年 | 11篇 |
1979年 | 11篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1976年 | 10篇 |
1975年 | 10篇 |
1974年 | 11篇 |
1973年 | 5篇 |
1972年 | 5篇 |
1971年 | 6篇 |
1970年 | 5篇 |
1959年 | 5篇 |
1950年 | 4篇 |
排序方式: 共有841条查询结果,搜索用时 0 毫秒
831.
Willem C. Hülsmann Marie-Louise Dubelaar L. Elly A. De Wit Niek L. M. Persoon 《Molecular and cellular biochemistry》1988,79(2):137-145
Summary Lipopolysaccharide (LPS), the active principle of certain endotoxins, protein-free perfused in rat hearts leads in 3 h to
a considerable loss of lipoprotein lipase (LPL) activity. In the presence of albumin LPS has virtually no effect. Tumor necrosis
factor (TNF) added instead of LPS had no effects on LPL activity during 3 hin vitro perfusion.
LPS injected into rats intravenously leads within 3 h to severe toxic phenomena amongst which increased capillary permeability.
This was visualized as increased rate of interstitial fluid formation in Langendorff hearts mounted 3 h after rats had been
treated with LPS. LPL activity did not decline in 3 h lasting endotoxemia. Six hours after LPS injection, however, cardiac
LPL activity was considerably lowered, although immunoblotting and immunohistochemistry still showed LPL protein to be present.
These date indicate the presence of a considerable pool of inactive LPL protein in addition to active LPL, that can be released
in the presence of heparin. The LPL activity is lowered by LPS injection after a lag phase of at least 3 h, while capillary
endothelial cells are influenced more rapidly. The relatively late expression of TNF toxicity in cardiomyocytes of the intact
heart is discussed. 相似文献
832.
833.
Summary Tumor Necrosis Factor (TNF) inhibits lipoprotein lipase activity in cultured myocytes and in the Langendorff rat heart after
3 h perfusion with TNF of glucocorticoid-pretreated rats. TNF acutely stimulates glyc(ogen)olysis and concomitantly endogenous
lipolysis. The latter was significantly increased only when rats had been pretreated with glucocorticoid or fed a trierucate-rich
diet. Under these conditions, contractile activity of the Langendorff hearts was acutely increased by TNF The mechanism of
the actue increase of contractile function and the accompanying increased glycolytic and lipolytic activities, by TNF, may
be explained by increased cytosolic Ca2+ and cAMP levels. 相似文献
834.
835.
Dictyostelium discoideum amoebae were employed to study the refractoriness and adaptation of the rapid (5sec) accumulation of actin in their Triton-insoluble cytoskeletons following stimulation with specific chemoattractants. Amoebae became refractory within 10sec for this response but no adaptation occurred during this period. Amoebae desensitized for one attractant were not desensitized for another and responses to stimulation with a mixture of attractants were approximately additive. The characteristics of these processes are compared to published studies of adaptation in other chemoattractant-induced responses and a new model for the chemotactic signal transduction pathway is formulated. We conclude that intracellular cGMP accumulation may be on a separate branch of the pathway from the actin response. 相似文献
836.
837.
838.
839.
840.
Marie-Louise Kann Jean-Pierre Fouquet 《Biology of the cell / under the auspices of the European Cell Biology Organization》1993,77(3):311-313
Summary— In hamster and mouse spermatozoa a spectrin immunogold labeling was found under the plasma membrane in the principal piece of the flagellum. During spermatid differentiation, the spectrin labeling was associated with the manchette, a transient microtubular network involved in nuclear shaping and organelle translocation. 相似文献