全文获取类型
收费全文 | 63589篇 |
免费 | 5206篇 |
国内免费 | 3443篇 |
出版年
2024年 | 134篇 |
2023年 | 674篇 |
2022年 | 1585篇 |
2021年 | 2591篇 |
2020年 | 1750篇 |
2019年 | 2186篇 |
2018年 | 2367篇 |
2017年 | 1965篇 |
2016年 | 2675篇 |
2015年 | 3446篇 |
2014年 | 4130篇 |
2013年 | 4594篇 |
2012年 | 5422篇 |
2011年 | 5091篇 |
2010年 | 3507篇 |
2009年 | 3056篇 |
2008年 | 3617篇 |
2007年 | 3345篇 |
2006年 | 3008篇 |
2005年 | 2587篇 |
2004年 | 2447篇 |
2003年 | 2234篇 |
2002年 | 1902篇 |
2001年 | 1111篇 |
2000年 | 908篇 |
1999年 | 727篇 |
1998年 | 517篇 |
1997年 | 394篇 |
1996年 | 376篇 |
1995年 | 371篇 |
1994年 | 345篇 |
1993年 | 277篇 |
1992年 | 326篇 |
1991年 | 304篇 |
1990年 | 238篇 |
1989年 | 208篇 |
1988年 | 160篇 |
1987年 | 190篇 |
1986年 | 161篇 |
1985年 | 146篇 |
1984年 | 115篇 |
1983年 | 112篇 |
1982年 | 102篇 |
1981年 | 90篇 |
1980年 | 68篇 |
1979年 | 69篇 |
1978年 | 77篇 |
1977年 | 63篇 |
1976年 | 58篇 |
1973年 | 69篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Chun-Yu Liu Min Wang Hong-Min Yu Fang-Xuan Han Qiong-Shi Wu Xing-Jun Cai 《Bioscience, biotechnology, and biochemistry》2020,84(8):1621-1628
ABSTRACT A critical pathogenic factor in the development of lethal liver failure is cell death induced by the accumulation of lipid reactive oxygen species. In this study, we discovered and illuminated a new mechanism that led to alcoholic liver disease via ferroptosis, an iron-dependent regulated cell death. Study in vitro showed that both necroptosis inhibitor and ferroptosis inhibitors performed significantly protective effect on alcohol-induced cell death, while apoptosis inhibitor and autophagy inhibitor had no such effect. Our data also indicated that alcohol caused the accumulation of lipid peroxides and the mRNA expression of prostaglandin-endoperoxide synthase 2, reduced the protein expression of the specific light-chain subunit of the cystine/glutamate antiporter and glutathione peroxidase 4. Importantly, ferrostatin-1 significantly ameliorated liver injury that was induced by overdosed alcohol both in vitro and in vivo. These findings highlight that targeting ferroptosis serves as a hepatoprotective strategy for alcoholic liver disease treatment. 相似文献
992.
993.
994.
995.
Yohei Kurio Yosuke Koike Yu Kanesaki Satoru Watanabe Shigeki Ehira 《Molecular microbiology》2020,114(4):553-562
996.
Natsuki Osaka Yu kanesaki Megumi Watanabe Satoru Watanabe Taku Chibazakura Hiraku Takada Hirofumi Yoshikawa Kei Asai 《Molecular microbiology》2020,113(6):1155-1169
In bacteria, guanosine (penta)tetra-phosphate ([p]ppGpp) is essential for controlling intracellular metabolism that is needed to adapt to environmental changes, such as amino acid starvation. The (p)ppGpp0 strain of Bacillus subtilis, which lacks (p)ppGpp synthetase, is unable to form colonies on minimal medium. Here, we found suppressor mutations in the (p)ppGpp0 strain, in the purine nucleotide biosynthesis genes, prs, purF and rpoB/C, which encode RNA polymerase core enzymes. In comparing our work with prior studies of ppGpp0 suppressors, we discovered that methionine addition masks the suppression on minimal medium, especially of rpoB/C mutations. Furthermore, methionine addition increases intracellular GTP in rpoB suppressor and this effect is decreased by inhibiting GTP biosynthesis, indicating that methionine addition activated GTP biosynthesis and inhibited growth under amino acid starvation conditions in (p)ppGpp0 backgrounds. Furthermore, we propose that the increase in intracellular GTP levels induced by methionine is due to methionine derivatives that increase the activity of the de novo GTP biosynthesis enzyme, GuaB. Our study sheds light on the potential relationship between GTP homeostasis and methionine metabolism, which may be the key to adapting to environmental changes. 相似文献
997.
998.
999.
1000.
Jie Hao Jiani Cao Lei Wang Aijin Ma Si Chen Jinfeng Ding Liu Wang Boqiang Fu Yu Zhang Xuetao Pei Peng Xiang Qiyuan Li Yong Zhang Jiaxi Zhou Shijun Hu Junying Yu Jun Wei Huanxin Zhu Glyn Stacey Tongbiao Zhao Qi Zhou 《Cell proliferation》2020,53(12)
‘Requirements for Human Embryonic Stem Cells’ is the first set of guidelines on human embryonic stem cells in China, jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research. This standard specifies the technical requirements, test methods, test regulations, instructions for use, labelling requirements, packaging requirements, storage requirements and transportation requirements for human embryonic stem cells, which is applicable to the quality control for human embryonic stem cells. It was originally released by the China Society for Cell Biology on 26 February 2019 and was further revised on 30 April 2020. We hope that publication of these guidelines will promote institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardization of human embryonic stem cells for applications. 相似文献