全文获取类型
收费全文 | 19880篇 |
免费 | 1472篇 |
国内免费 | 3篇 |
专业分类
21355篇 |
出版年
2022年 | 82篇 |
2021年 | 188篇 |
2020年 | 144篇 |
2019年 | 155篇 |
2018年 | 316篇 |
2017年 | 270篇 |
2016年 | 475篇 |
2015年 | 853篇 |
2014年 | 803篇 |
2013年 | 1132篇 |
2012年 | 1349篇 |
2011年 | 1336篇 |
2010年 | 795篇 |
2009年 | 678篇 |
2008年 | 1181篇 |
2007年 | 1179篇 |
2006年 | 1115篇 |
2005年 | 1070篇 |
2004年 | 1013篇 |
2003年 | 937篇 |
2002年 | 845篇 |
2001年 | 450篇 |
2000年 | 466篇 |
1999年 | 419篇 |
1998年 | 182篇 |
1997年 | 159篇 |
1996年 | 142篇 |
1995年 | 148篇 |
1994年 | 130篇 |
1993年 | 107篇 |
1992年 | 246篇 |
1991年 | 235篇 |
1990年 | 219篇 |
1989年 | 180篇 |
1988年 | 186篇 |
1987年 | 161篇 |
1986年 | 147篇 |
1985年 | 130篇 |
1984年 | 125篇 |
1983年 | 99篇 |
1982年 | 93篇 |
1981年 | 110篇 |
1980年 | 85篇 |
1979年 | 114篇 |
1978年 | 109篇 |
1977年 | 83篇 |
1976年 | 96篇 |
1975年 | 79篇 |
1974年 | 89篇 |
1971年 | 83篇 |
排序方式: 共有10000条查询结果,搜索用时 8 毫秒
91.
The secondary structures of cow and sheep kappa-caseins were established according to the predictive rules of Chou and Fasman. The diagrams derived from this treatment allowed us to study the chymosin sensitive bond (milk-clotting process), as well as the glycosylation and phosphorylation sites, found to be situated in beta-turns. Despite a high variability between the primary structures of the COOH-terminal part (caseinoglycopeptide) of cow, sheep, and also other caseins, the secondary structures of the biologically important sites were found to be conserved. 相似文献
92.
93.
Umberto Tomati Giovanni Giovannozzi-Sermanni Silvestro Duprè Carlo Cannella 《Phytochemistry》1976,15(5):597-598
The NADH: nitrate reductase from durum wheat leaves was inactivated by cyanide and its activity restored by thiosulphate and beef kidney rhodanese. Rhodanese and thiosulphate, added to NADH-nitrate reductase before cyanide treatment protected NADH-nitrate reductase activity. No oxidizing agent was required for the protection or restoration of cyanide treated NADH-nitrate reductase. 相似文献
94.
A Scheen J Juchmès G Lennes J Lecomte 《Archives internationales de physiologie et de biochimie》1976,84(5):915-923
VO2 max, maximum oxygen uptake, has been measured in 4 normal young men, before and after beta-adrenergic blockade (0.5 to 5 mg Pindolol by mouth). Pindolol induces bradycardia and reduces VO2 max. A statistically significant positive correlation appears between posology of Pindolol and bradycardia, this posology and reduction of VO2 max, and finally between bradycardia and reduction of VO2 max. These correlations indicate that the reduction of VO2 max is best explained by a circulatory limitation of oxygen supply to active muscles. 相似文献
95.
A method for electrophoretic detection of NAD(P)+ase solubilized from red cell membranes is described. The method reveals both NAD+ase and NADP+ase and can be applied to a screening procedure for the detection of electrophoretic variants. The initial chracterization of the solubilized enzyme is also described. 相似文献
96.
97.
98.
99.
The Concanavalin A agglutinating system of cell membranes. 总被引:1,自引:0,他引:1
Nejat Düzgüneş 《Bio Systems》1975,6(4):209-216
The hopes raised by the finding of differential Concanavalin A (Con A) agglutinability of normal and transformed cells in efforts to quantify differences between these cell lines seem not to have been justified. In this paper, the development of information on the mechanism of action of Con A on the cell surface, as well as the theories put forward at each stage of this development are surveyed. In this respect, investigations on Con A constitute a case history in biological research. The involvement of glycoproteins and galactosyltransferases in cell-cell interactions and their relations to Con A are also reviewed. 相似文献
100.
Harshad S. Ugamraj Kevin Dang Laure-Hlne Ouisse Benjamin Buelow Eduardo N. Chini Giulia Castello James Allison Starlynn C Clarke Laura M. Davison Roland Buelow Rong Deng Suhasini Iyer Ute Schellenberger Sankar N. Manika Shipra Bijpuria Astrid Musnier Anne Poupon Maria Cristina Cuturi Wim van Schooten Pranjali Dalvi 《MABS-AUSTIN》2022,14(1)