全文获取类型
收费全文 | 6498篇 |
免费 | 600篇 |
国内免费 | 5篇 |
出版年
2023年 | 26篇 |
2022年 | 48篇 |
2021年 | 112篇 |
2020年 | 64篇 |
2019年 | 107篇 |
2018年 | 93篇 |
2017年 | 96篇 |
2016年 | 160篇 |
2015年 | 310篇 |
2014年 | 327篇 |
2013年 | 349篇 |
2012年 | 475篇 |
2011年 | 446篇 |
2010年 | 274篇 |
2009年 | 275篇 |
2008年 | 379篇 |
2007年 | 392篇 |
2006年 | 372篇 |
2005年 | 383篇 |
2004年 | 343篇 |
2003年 | 313篇 |
2002年 | 302篇 |
2001年 | 83篇 |
2000年 | 47篇 |
1999年 | 79篇 |
1998年 | 77篇 |
1997年 | 58篇 |
1996年 | 49篇 |
1995年 | 60篇 |
1994年 | 53篇 |
1993年 | 47篇 |
1992年 | 46篇 |
1991年 | 39篇 |
1990年 | 44篇 |
1989年 | 33篇 |
1988年 | 31篇 |
1987年 | 50篇 |
1986年 | 23篇 |
1985年 | 33篇 |
1984年 | 42篇 |
1983年 | 43篇 |
1982年 | 42篇 |
1981年 | 38篇 |
1980年 | 28篇 |
1979年 | 32篇 |
1978年 | 29篇 |
1977年 | 27篇 |
1976年 | 39篇 |
1974年 | 26篇 |
1973年 | 30篇 |
排序方式: 共有7103条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
995.
Patricia B. Miller Hua Shen Neil R. Gilkes Douglas G. Kilburn Robert C. Miller Jr. Andrew G. Plaut R.Antony J. Warren 《FEMS microbiology letters》1992,92(2):199-203
The hinge in IgA1 and the linker in endoglucanase A (CenA) are quite similar. The IgA1 hinge is 18 amino acids long and contains only proline, threonine and serine. The linker in CenA is 27 amino acids long and contains only proline, threonine and a single serine. IgA proteases from Neisseria gonorrhoeae cleave Pro-Ser and Pro-Thr bonds within the IgA1 hinge sequence, but they do not attack CenA. When the linker sequence of CenA is replaced with the hinge sequence of IgA1, the hybrid polypeptide is susceptible to the N. gonorrhoeae proteases. It is cleaved within the hinge sequence at the same sites as IgA1. 相似文献
996.
997.
Michael J. Sandery John W. Forster Simon R. Macadam Richard Blunden R. Neil Jones Stephen D. M. Brown 《Plant Molecular Biology Reporter》1991,9(1):21-30
The techniques of microdissection and microcloning have been applied to the isolation of B-chromosome DNA from rye. We have
identified a DNA sequence on the rye B-chromosome which is homologous to an A-chromosome sequence, and which is dispersed
and moderately repeated on the A- and B-chromosomes. This demonstrates that the rye B-chromosome is heterogeneous in the nature
of its DNA sequence composition, containing sequences which are present on the A-chromosomes in addition to those not present
on the A-chromosomes. 相似文献
998.
Carlos Gorbea Kimberly A. Makar Matthias Pauschinger Gregory Pratt Jeathrina L. F. Bersola Jacquelin Varela Ryan M. David Lori Banks Chien-Hua Huang Hua Li Heinz-Peter Schultheiss Jeffrey A. Towbin Jesús G. Vallejo Neil E. Bowles 《The Journal of biological chemistry》2010,285(30):23208-23223
The innate antiviral response is mediated, at least in part, by Toll-like receptors (TLRs). TLR3 signaling is activated in response to viral infection, and the absence of TLR3 in mice significantly increases mortality after infection with enteroviruses that cause myocarditis and/or dilated cardiomyopathy. We screened TLR3 in patients diagnosed with enteroviral myocarditis/cardiomyopathy and identified a rare variant in one patient as well as a significantly increased occurrence of a common polymorphism compared with controls. Expression of either variant resulted in significantly reduced TLR3-mediated signaling after stimulation with synthetic double-stranded RNA. Furthermore, Coxsackievirus B3 infection of cell lines expressing mutated TLR3 abrogated activation of the type I interferon pathway, leading to increased viral replication. TLR3-mediated type I interferon signaling required cellular autophagy and was suppressed by 3-methyladenine and bafilomycin A1, by inhibitors of lysosomal proteolysis, and by reduced expression of Beclin 1, Atg5, or microtubule-associated protein 1 light chain 3β (MAP1LC3β). However, TLR3-mediated signaling was restored upon exogenous expression of Beclin 1 or a variant MAP1LC3β fusion protein refractory to RNA interference. These data suggest that individuals harboring these variants may have a blunted innate immune response to enteroviral infection, leading to reduced viral clearance and an increased risk of cardiac pathology. 相似文献
999.
1000.