全文获取类型
收费全文 | 48046篇 |
免费 | 17513篇 |
国内免费 | 2431篇 |
出版年
2024年 | 19篇 |
2023年 | 271篇 |
2022年 | 413篇 |
2021年 | 1188篇 |
2020年 | 2755篇 |
2019年 | 4518篇 |
2018年 | 4570篇 |
2017年 | 4745篇 |
2016年 | 4908篇 |
2015年 | 5251篇 |
2014年 | 5276篇 |
2013年 | 5802篇 |
2012年 | 4005篇 |
2011年 | 3521篇 |
2010年 | 4321篇 |
2009年 | 2916篇 |
2008年 | 2138篇 |
2007年 | 1506篇 |
2006年 | 1376篇 |
2005年 | 1329篇 |
2004年 | 1304篇 |
2003年 | 1200篇 |
2002年 | 1091篇 |
2001年 | 836篇 |
2000年 | 598篇 |
1999年 | 406篇 |
1998年 | 236篇 |
1997年 | 172篇 |
1996年 | 140篇 |
1995年 | 150篇 |
1994年 | 149篇 |
1993年 | 83篇 |
1992年 | 127篇 |
1991年 | 119篇 |
1990年 | 81篇 |
1989年 | 74篇 |
1988年 | 43篇 |
1987年 | 36篇 |
1986年 | 35篇 |
1985年 | 31篇 |
1984年 | 19篇 |
1983年 | 26篇 |
1982年 | 18篇 |
1981年 | 13篇 |
1980年 | 23篇 |
1979年 | 20篇 |
1977年 | 18篇 |
1975年 | 14篇 |
1974年 | 16篇 |
1970年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
1.
2.
Detection and genotyping of group A rotaviruses isolated from sewage samples in Monastir,Tunisia between April 2007 and April 2010 下载免费PDF全文
3.
4.
5.
6.
7.
8.
Jung Mi Lim Kyung S. Lee Hyun Ae Woo Dongmin Kang Sue Goo Rhee 《The Journal of cell biology》2015,210(1):935-945
Proteins associated with the centrosome play key roles in mitotic progression in mammalian cells. The activity of Cdk1-opposing phosphatases at the centrosome must be inhibited during early mitosis to prevent premature dephosphorylation of Cdh1—an activator of the ubiquitin ligase anaphase-promoting complex/cyclosome—and the consequent premature degradation of mitotic activators. In this paper, we show that reversible oxidative inactivation of centrosome-bound protein phosphatases such as Cdc14B by H2O2 is likely responsible for this inhibition. The intracellular concentration of H2O2 increases as the cell cycle progresses. Whereas the centrosome is shielded from H2O2 through its association with the H2O2-eliminating enzyme peroxiredoxin I (PrxI) during interphase, the centrosome-associated PrxI is selectively inactivated through phosphorylation by Cdk1 during early mitosis, thereby exposing the centrosome to H2O2 and facilitating inactivation of centrosome-bound phosphatases. Dephosphorylation of PrxI by okadaic acid–sensitive phosphatases during late mitosis again shields the centrosome from H2O2 and thereby allows the reactivation of Cdk1-opposing phosphatases at the organelle. 相似文献
9.
10.
J.-Y. Roh H.-W. Park Y.-H. Je D.-W. Lee B.-R. Jin H.-W. Oh S. S. Gill & S.-K. Kang 《Letters in applied microbiology》1997,24(6):451-454
Bacillus thuringiensis NTB-1 isolated from soil samples in Korea produces ovoidal parasporal inclusions with proteins of approximately 24–40 kDa in size. Although serological study indicated that the isolate has a flagella (H) antigen identical with subsp. israelensis , it seemed to be non-insecticidal against Lepidoptera and Coleoptera as well as Diptera. To investigate the activity of non-insecticidal B. thuringiensis transformed with insecticidal crystal protein genes, cryIVD and cytA genes of B. thuringiensis subsp. morrisoni PG-14, highly toxic to mosquito larvae, were introduced into the isolate NTB-1. The expression of mosquitocidal crystal protein genes in NTB-1 was characterized by SDS–PAGE analysis and electron microscopy. The results showed that crystalline inclusions of host, CryIVD and CytA were stably expressed in the transformant. However, the mosquitocidal activity of transformant was similar to that of B. thuringiensis subsp. kurstaki Cry− B harbouring cryIVD and cytA genes, demonstrating that a synergistic effect by an interaction of both introduced insecticidal and resident non-insecticidal crystal proteins was not observed. 相似文献