全文获取类型
收费全文 | 688185篇 |
免费 | 69531篇 |
国内免费 | 428篇 |
专业分类
758144篇 |
出版年
2018年 | 7721篇 |
2017年 | 7229篇 |
2016年 | 10106篇 |
2015年 | 12757篇 |
2014年 | 14785篇 |
2013年 | 20538篇 |
2012年 | 23164篇 |
2011年 | 23505篇 |
2010年 | 16007篇 |
2009年 | 14170篇 |
2008年 | 20683篇 |
2007年 | 21142篇 |
2006年 | 20163篇 |
2005年 | 18871篇 |
2004年 | 18748篇 |
2003年 | 17779篇 |
2002年 | 17247篇 |
2001年 | 28087篇 |
2000年 | 27996篇 |
1999年 | 22054篇 |
1998年 | 7706篇 |
1997年 | 7855篇 |
1996年 | 7526篇 |
1995年 | 7044篇 |
1994年 | 6810篇 |
1992年 | 18001篇 |
1991年 | 17743篇 |
1990年 | 17498篇 |
1989年 | 17154篇 |
1988年 | 16121篇 |
1987年 | 15467篇 |
1986年 | 14194篇 |
1985年 | 14406篇 |
1984年 | 11896篇 |
1983年 | 10320篇 |
1982年 | 7792篇 |
1981年 | 7060篇 |
1980年 | 6716篇 |
1979年 | 11386篇 |
1978年 | 8860篇 |
1977年 | 8244篇 |
1976年 | 7932篇 |
1975年 | 8803篇 |
1974年 | 9680篇 |
1973年 | 9580篇 |
1972年 | 8763篇 |
1971年 | 8024篇 |
1970年 | 7183篇 |
1969年 | 6977篇 |
1968年 | 6747篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
92.
A. Španová 《Folia microbiologica》1980,25(4):281-288
Temperature-sensitive (ts) mutations of the G101 phage were isolated after mutagenesis with hydroxylamine. A complementation analysis of 61ts mutants showed that these mutants may be divided into at least 12 complementation groups. Twots mutants probably originated in genes which control lytic functions of the G101 phage. It was shown by three factor crosses
that all of the 12ts mutations tested are localized on that side of the “c” region where the probablecI repressor gene is positioned. Sevents mutations is closely linked to thecI
26 clear marker, three exhibit a closer linkage and two do not exhibit any linkage withcI. All mutations isolated until now can be arrange linearly. According to the present knowledge the preliminary genetic map
of the G101 phage is linear. 相似文献
93.
94.
95.
Donald E. Rivett Dean Hewish Alan Kirkpatrick Jerome Werkmeister 《Journal of Protein Chemistry》1999,18(3):291-295
Nine fatty acid–peptide hybrid molecules were constructed using the general formula CH3(CH2)
n
CO-Phe Asp Cys-amide and tested for their ability to inhibit cell lysis induced by the membrane-active peptide melittin. All of these molecules, where n = 4–14, inhibited the action of melittin to some extent, but the longer carbon chains were most effective. Several potential inhibitors were also constructed with conservative substitutions in the peptide portion of the molecule. All were effective to varying degrees. We concluded that in the hexapeptide inhibitor published by Blondelle et al. (1993), the role of the first three residues is only to provide hydrophobic interaction with the melittin and has no particular amino acid sequence specificity. Some of these inhibitors were found to inhibit the lytic activity of a melittin analogue which had only superficial sequence similarity to melittin and also a truncated form of melittin, indicating the generality of the action of the inhibitors.Deceased 5/4/98 相似文献
96.
97.
98.
99.
HIF-1 expression in healing wounds: HIF-1alpha induction in primary inflammatory cells by TNF-alpha 总被引:12,自引:0,他引:12
100.