全文获取类型
收费全文 | 113600篇 |
免费 | 2131篇 |
国内免费 | 2169篇 |
出版年
2024年 | 36篇 |
2023年 | 197篇 |
2022年 | 491篇 |
2021年 | 848篇 |
2020年 | 620篇 |
2019年 | 786篇 |
2018年 | 12496篇 |
2017年 | 11129篇 |
2016年 | 8244篇 |
2015年 | 1972篇 |
2014年 | 1897篇 |
2013年 | 1983篇 |
2012年 | 6147篇 |
2011年 | 14557篇 |
2010年 | 13030篇 |
2009年 | 9210篇 |
2008年 | 10943篇 |
2007年 | 12400篇 |
2006年 | 1285篇 |
2005年 | 1375篇 |
2004年 | 1806篇 |
2003年 | 1694篇 |
2002年 | 1320篇 |
2001年 | 614篇 |
2000年 | 447篇 |
1999年 | 278篇 |
1998年 | 199篇 |
1997年 | 173篇 |
1996年 | 158篇 |
1995年 | 117篇 |
1994年 | 115篇 |
1993年 | 92篇 |
1992年 | 108篇 |
1991年 | 107篇 |
1990年 | 87篇 |
1989年 | 69篇 |
1988年 | 61篇 |
1987年 | 58篇 |
1986年 | 27篇 |
1985年 | 27篇 |
1984年 | 40篇 |
1983年 | 30篇 |
1982年 | 12篇 |
1981年 | 7篇 |
1972年 | 246篇 |
1971年 | 274篇 |
1965年 | 14篇 |
1962年 | 25篇 |
1944年 | 12篇 |
1940年 | 10篇 |
排序方式: 共有10000条查询结果,搜索用时 125 毫秒
91.
92.
93.
Xinzhu Deng David Michaelson Jason Tchieu Jin Cheng Diana Rothenstein Regina Feldman Sang-gyu Lee John Fuller Adriana Haimovitz-Friedman Lorenz Studer Simon Powell Zvi Fuks E. Jane Albert Hubbard Richard Kolesnick 《PloS one》2015,10(6)
Mammalian NOTCH1-4 receptors are all associated with human malignancy, although exact roles remain enigmatic. Here we employ glp-1(ar202), a temperature-sensitive gain-of-function C. elegans NOTCH mutant, to delineate NOTCH-driven tumor responses to radiotherapy. At ≤20°C, glp-1(ar202) is wild-type, whereas at 25°C it forms a germline stem cell⁄progenitor cell tumor reminiscent of human cancer. We identify a NOTCH tumor phenotype in which all tumor cells traffic rapidly to G2⁄M post-irradiation, attempt to repair DNA strand breaks exclusively via homology-driven repair, and when this fails die by mitotic death. Homology-driven repair inactivation is dramatically radiosensitizing. We show that these concepts translate directly to human cancer models. 相似文献
94.
Melissa A. Partridge Sumana Gopinath Simon J. Myers Jens R Coorssen 《Journal of chemical biology》2016,9(1):9-18
An initial proteomic analysis of the cuprizone mouse model to characterise the breadth of toxicity by assessing cortex, skeletal muscle, spleen and peripheral blood mononuclear cells. Cuprizone treated vs. control mice for an initial characterisation. Select tissues from each group were pooled, analysed in triplicate using two-dimensional gel electrophoresis (2DE) and deep imaging and altered protein species identified using liquid chromatography tandem mass spectrometry (LC/MS/MS). Forty-three proteins were found to be uniquely detectable or undetectable in the cuprizone treatment group across the tissues analysed. Protein species identified in the cortex may potentially be linked to axonal damage in this model, and those in the spleen and peripheral blood mononuclear cells to the minimal peripheral immune cell infiltration into the central nervous system during cuprizone mediated demyelination. Primary oligodendrocytosis has been observed in type III lesions in multiple sclerosis. However, the underlying mechanisms are poorly understood. Cuprizone treatment results in oligodendrocyte apoptosis and secondary demyelination. This initial analysis identified proteins likely related to axonal damage; these may link primary oligodendrocytosis and secondary axonal damage. Furthermore, this appears to be the first study of the cuprizone model to also identify alterations in the proteomes of skeletal muscle, spleen and peripheral blood mononuclear cells. Notably, protein disulphide isomerase was not detected in the cuprizone cohort; its absence has been linked to reduced major histocompatibility class I assembly and reduced antigen presentation. Overall, the results suggest that, like experimental autoimmune encephalomyelitis, results from the standard cuprizone model should be carefully considered relative to clinical multiple sclerosis. 相似文献
95.
Tapas K. Nandi Hridoy R. Bairagya Bishnu P. Mukhopadhyay K. Sekar Dipankar Sukul Asim K. Bera 《Journal of biosciences》2009,34(1):27-34
The role of invariant water molecules in the activity of plant cysteine protease is ubiquitous in nature. On analysing the
11 different Protein DataBank (PDB) structures of plant thiol proteases, the two invariant water molecules W1 and W2 (W220
and W222 in the template 1PPN structure) were observed to form H-bonds with the Ob atom of Asn 175. Extensive energy minimization and molecular dynamics simulation studies up to 2 ns on all the PDB and solvated
structures clearly revealed the involvement of the H-bonding association of the two water molecules in fixing the orientation
of the asparagine residue of the catalytic triad. From this study, it is suggested that H-bonding of the water molecule at
the W1 invariant site better stabilizes the Asn residue at the active site of the catalytic triad. 相似文献
96.
SUMO化是一种重要的蛋白质翻译后修饰,对植物正常生长发育不可或缺。到目前为止已筛选到上千个可能的SUMO底物,但由于SUMO化修饰水平普遍很低,其生物学功能研究相对较少。该文详细描述了检测蛋白SUMO化修饰的常用方法,包括体外和体内SUMO化实验,以及SUMO化修饰位点的检测方法,旨在为深入研究植物蛋白SUMO化修饰提供技术支持。 相似文献
97.
98.
99.
100.
Mingyue Wang Pranab K Mukherjee Jyotsna Chandra Ali Abdul Lattif Thomas S McCormick Mahmoud A Ghannoum 《BMC microbiology》2008,8(1):31