全文获取类型
收费全文 | 3571篇 |
免费 | 197篇 |
出版年
2022年 | 39篇 |
2021年 | 75篇 |
2020年 | 39篇 |
2019年 | 57篇 |
2018年 | 54篇 |
2017年 | 66篇 |
2016年 | 84篇 |
2015年 | 128篇 |
2014年 | 139篇 |
2013年 | 173篇 |
2012年 | 232篇 |
2011年 | 209篇 |
2010年 | 135篇 |
2009年 | 115篇 |
2008年 | 163篇 |
2007年 | 136篇 |
2006年 | 128篇 |
2005年 | 117篇 |
2004年 | 109篇 |
2003年 | 80篇 |
2002年 | 85篇 |
2001年 | 89篇 |
2000年 | 64篇 |
1999年 | 69篇 |
1998年 | 28篇 |
1997年 | 32篇 |
1996年 | 26篇 |
1995年 | 24篇 |
1992年 | 52篇 |
1991年 | 61篇 |
1990年 | 47篇 |
1989年 | 55篇 |
1988年 | 39篇 |
1987年 | 49篇 |
1986年 | 31篇 |
1985年 | 76篇 |
1984年 | 46篇 |
1983年 | 52篇 |
1982年 | 24篇 |
1981年 | 29篇 |
1980年 | 41篇 |
1979年 | 53篇 |
1978年 | 33篇 |
1976年 | 25篇 |
1975年 | 27篇 |
1974年 | 32篇 |
1973年 | 28篇 |
1971年 | 34篇 |
1970年 | 29篇 |
1969年 | 33篇 |
排序方式: 共有3768条查询结果,搜索用时 23 毫秒
1.
Shailesh Kumar Atma P. Dwivedi Vivek Kr. Kashyap A.K. Saxena A.K. Dwivedi Ranjana Srivastava Devi P. Sahu 《Bioorganic & medicinal chemistry letters》2013,23(8):2404-2407
Synthesis of a library of novel trans 6-methoxy-1,1-dimethyl-2-phenyl-3-aryl-2,3-dihydro-1H-inden-4-yloxy alkyl amines and their antimycobacterial activity against drug sensitive and multidrug resistant strains of Mycobacterium tuberculosis have been reported. All the new compounds in the series exhibited MIC between 1.56 and 6.25 μg/ml. Two compounds 1i and 1j with low MIC and low cytotoxicity showed significant reduction in CFU in infected mouse macrophages at 1× MIC concentration. The compound 1i inhibited the growth of M. tuberculosis in mice at 100 mg/kg dose with 1.35 log10 reduction of CFU in lungs tissue and was active against non-replicating Mycobacterium tuberculosis under anaerobic condition. 相似文献
2.
A C Srivastava A J Pinching M W Adler R Robertson R Higgs 《BMJ (Clinical research ed.)》1987,294(6570):495-496
Dr A C Srivastava has written to us to describe a case that raises the suggestion that people infected with the human immuno-deficiency virus (HIV) should carry identity cards. We asked two physicians, a general practitioner working with patients with the acquired immune deficiency syndrome (AIDS), and a general practitioner with a special interest in medical ethics to respond to the broad issues raised by Dr Srivastava''s letter. 相似文献
3.
A bioactive peptide of 8595 Da was purified from the cell free supernatant of Lactococcus garvieae subsp. bovis BSN307T. MALDI MS/MS peptide mapping and the data base search displayed no significant similarity to any reported antimicrobial peptide of LAB. This peptide at a dose concentration of 200 µg ml−1 inhibited the growth of both Gram-positive and Gram-negative bacteria by 58–89% and a dose of 500 µg ml−1 scavenged 50% of DPPH-free radicals generated. Interestingly, cytotoxicity assay demonstrated that 17 µg ml−1 of peptide selectively inhibited 50% proliferation of mammalian cancer cell lines HeLa and MCF-7 whereas normal H9c2 cells remained unaffected. Fluorescent microscopic analysis after DAPI nuclear staining of HeLa cells showed characteristics of apoptosis and activation of caspase-3 was ascertained by caspase-3 fluorescence assay. 相似文献
4.
5.
Molecular and Cellular Biochemistry - 相似文献
6.
7.
8.
9.
10.
A K Srivastava C Pandey K P Dwivedi V K Singh 《Indian journal of biochemistry & biophysics》1989,26(3):199-200
QSAR studies have been performed on the homologues of 3-triazines, using molecular connectivity index and van der Waal volume as structural parameters. The regression analysis has shown good correlation between antitumour activity and the two structural parameters. 相似文献