全文获取类型
收费全文 | 360992篇 |
免费 | 28042篇 |
国内免费 | 92篇 |
专业分类
389126篇 |
出版年
2018年 | 4184篇 |
2017年 | 4035篇 |
2016年 | 5093篇 |
2015年 | 4961篇 |
2014年 | 6611篇 |
2013年 | 9479篇 |
2012年 | 11082篇 |
2011年 | 11931篇 |
2010年 | 8309篇 |
2009年 | 7320篇 |
2008年 | 10619篇 |
2007年 | 11085篇 |
2006年 | 10598篇 |
2005年 | 9893篇 |
2004年 | 10122篇 |
2003年 | 9748篇 |
2002年 | 9724篇 |
2001年 | 15846篇 |
2000年 | 15723篇 |
1999年 | 12033篇 |
1998年 | 3822篇 |
1997年 | 3776篇 |
1996年 | 3429篇 |
1995年 | 3166篇 |
1992年 | 9535篇 |
1991年 | 9734篇 |
1990年 | 9492篇 |
1989年 | 9494篇 |
1988年 | 8758篇 |
1987年 | 8248篇 |
1986年 | 7535篇 |
1985年 | 7854篇 |
1984年 | 6338篇 |
1983年 | 5317篇 |
1982年 | 3617篇 |
1981年 | 3181篇 |
1980年 | 3134篇 |
1979年 | 5966篇 |
1978年 | 4646篇 |
1977年 | 4231篇 |
1976年 | 3996篇 |
1975年 | 4807篇 |
1974年 | 5314篇 |
1973年 | 5272篇 |
1972年 | 4799篇 |
1971年 | 4486篇 |
1970年 | 3898篇 |
1969年 | 3796篇 |
1968年 | 3558篇 |
1967年 | 3203篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
952.
T. Lingaraja P. Sasi Bhushana Rao V. K. Venugopalan 《Environmental Biology of Fishes》1979,4(1):83-88
Synopsis Experiments were carried out to study the feeding rates of the predator fish Therapon jarbua (Forsk) on mullet juveniles, before and after treatment with DDT. Mullet juveniles treated with a subacute concentration, were refused by the control predators, whereas predators treated with a subacute concentration consumed more mullet juveniles. In the present study crescent perch T. jarbua were exposed to subacute and acute concentrations of DDT, and their behaviour was compared with that of the control predators. There were changes in oriented behaviour and co-ordinated movements, and in feeding, aggression and comfort behaviour of the fish. Inflammation in the gills, and caudal fin serration, were noticed in treated fishes. The findings presented here throw light on fundamental pathways by which pollutants interact with the behaviour of fishes. 相似文献
953.
954.
The effects of ionic strength, urea, calcium and fluorine ions, ouabain and cholinesterase inhibitors on the changes in the ionization equilibrium of an erythrocyte suspension under heating were studied. Proton release by erythrocytes was compared to a release of potassium ions and hemoglobin from the cells. The proton release under heating is mainly determined by the physico--chemical properties of superficial structures of erythrocytes and does not depend on the activity of cholinesterase, ATPase and glycolytic processes. 相似文献
955.
956.
957.
958.
959.
960.
R J Stockert A G Morell I H Scheinberg 《Biochemical and biophysical research communications》1976,68(3):988-993
Oligosaccharide chains of agalactoorosomucoid, α1-acid glycoprotein from which sialic acid and galactose have been sequentially removed, terminate in N-acetylglucosaminyl residues. This protein is rapidly transferred from the circulation into the liver by a route distinct from that previously demonstrated for a number of galactosyl terminating glycoproteins. 相似文献