全文获取类型
收费全文 | 146565篇 |
免费 | 10967篇 |
国内免费 | 10767篇 |
专业分类
168299篇 |
出版年
2024年 | 315篇 |
2023年 | 1774篇 |
2022年 | 4089篇 |
2021年 | 6817篇 |
2020年 | 4617篇 |
2019年 | 5714篇 |
2018年 | 5643篇 |
2017年 | 4248篇 |
2016年 | 6003篇 |
2015年 | 8773篇 |
2014年 | 10238篇 |
2013年 | 11114篇 |
2012年 | 13216篇 |
2011年 | 12131篇 |
2010年 | 7326篇 |
2009年 | 6666篇 |
2008年 | 7834篇 |
2007年 | 6930篇 |
2006年 | 6150篇 |
2005年 | 5272篇 |
2004年 | 4432篇 |
2003年 | 4015篇 |
2002年 | 3354篇 |
2001年 | 2700篇 |
2000年 | 2482篇 |
1999年 | 2424篇 |
1998年 | 1427篇 |
1997年 | 1414篇 |
1996年 | 1352篇 |
1995年 | 1215篇 |
1994年 | 1091篇 |
1993年 | 867篇 |
1992年 | 1142篇 |
1991年 | 934篇 |
1990年 | 783篇 |
1989年 | 627篇 |
1988年 | 514篇 |
1987年 | 494篇 |
1986年 | 377篇 |
1985年 | 375篇 |
1984年 | 248篇 |
1983年 | 238篇 |
1982年 | 126篇 |
1981年 | 88篇 |
1980年 | 72篇 |
1979年 | 96篇 |
1978年 | 60篇 |
1977年 | 54篇 |
1975年 | 57篇 |
1973年 | 45篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
161.
162.
163.
A subsystem impactor test for pedestrian lower limb injury evaluation has been brought in China New Car Assessment Protocol(CNCAP).Concerning large anthropometr... 相似文献
164.
Nicola Pirastu Ciara McDonnell Eryk J. Grzeszkowiak Ninon Mounier Fumiaki Imamura Jordi Merino Felix R. Day Jie Zheng Nele Taba Maria Pina Concas Linda Repetto Katherine A. Kentistou Antonietta Robino Tnu Esko Peter K. Joshi Krista Fischer Ken K. Ong Tom R. Gaunt Zoltn Kutalik John R. B. Perry James F. Wilson 《PLoS genetics》2022,18(6)
Diet is considered as one of the most important modifiable factors influencing human health, but efforts to identify foods or dietary patterns associated with health outcomes often suffer from biases, confounding, and reverse causation. Applying Mendelian randomization in this context may provide evidence to strengthen causality in nutrition research. To this end, we first identified 283 genetic markers associated with dietary intake in 445,779 UK Biobank participants. We then converted these associations into direct genetic effects on food exposures by adjusting them for effects mediated via other traits. The SNPs which did not show evidence of mediation were then used for MR, assessing the association between genetically predicted food choices and other risk factors, health outcomes. We show that using all associated SNPs without omitting those which show evidence of mediation, leads to biases in downstream analyses (genetic correlations, causal inference), similar to those present in observational studies. However, MR analyses using SNPs which have only a direct effect on the exposure on food exposures provided unequivocal evidence of causal associations between specific eating patterns and obesity, blood lipid status, and several other risk factors and health outcomes. 相似文献
165.
Bingqing Xia Xurui Shen Yang He Xiaoyan Pan Feng-Liang Liu Yi Wang Feipu Yang Sui Fang Yan Wu Zilei Duan Xiaoli Zuo Zhuqing Xie Xiangrui Jiang Ling Xu Hao Chi Shuangqu Li Qian Meng Hu Zhou Yubo Zhou Xi Cheng Xiaoming Xin Lin Jin Hai-Lin Zhang Dan-Dan Yu Ming-Hua Li Xiao-Li Feng Jiekai Chen Hualiang Jiang Gengfu Xiao Yong-Tang Zheng Lei-Ke Zhang Jingshan Shen Jia Li Zhaobing Gao 《Cell research》2021,31(8):847-860
Cytokine storm and multi-organ failure are the main causes of SARS-CoV-2-related death. However, the origin of excessive damages caused by SARS-CoV-2 remains largely unknown. Here we show that the SARS-CoV-2 envelope (2-E) protein alone is able to cause acute respiratory distress syndrome (ARDS)-like damages in vitro and in vivo. 2-E proteins were found to form a type of pH-sensitive cation channels in bilayer lipid membranes. As observed in SARS-CoV-2-infected cells, heterologous expression of 2-E channels induced rapid cell death in various susceptible cell types and robust secretion of cytokines and chemokines in macrophages. Intravenous administration of purified 2-E protein into mice caused ARDS-like pathological damages in lung and spleen. A dominant negative mutation lowering 2-E channel activity attenuated cell death and SARS-CoV-2 production. Newly identified channel inhibitors exhibited potent anti-SARS-CoV-2 activity and excellent cell protective activity in vitro and these activities were positively correlated with inhibition of 2-E channel. Importantly, prophylactic and therapeutic administration of the channel inhibitor effectively reduced both the viral load and secretion of inflammation cytokines in lungs of SARS-CoV-2-infected transgenic mice expressing human angiotensin-converting enzyme 2 (hACE-2). Our study supports that 2-E is a promising drug target against SARS-CoV-2.Subject terms: Cell death, Molecular biology 相似文献
166.
Lin Zhang Yiming Chen Fahui Li Lihui Zhang Jinhong Feng Lei Zhang 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1918
Histone deacetylases (HDACs) are validated targets for the development of anticancer drugs in epigenetics. In the discovery of novel HDAC inhibitors with anticancer potency, the 5-chloro-4-((substituted phenyl)amino)pyrimidine fragment is assembled as a cap group into the structure of HDAC inhibitors. The SAR revealed that presence of small groups (such as methoxy substitution) is beneficial for the HDAC inhibitory activity. In the enzyme inhibitory selectivity test, compound L20 exhibited class I selectivity with IC50 values of 0.684 µM (selectivity index of >1462), 2.548 µM (selectivity index of >392), and 0.217 µM (selectivity index of >4608) against HDAC1, HDAC2 and HDAC3 compared with potency against HDAC6 (IC50 value of >1000 µM), respectively. In the antiproliferative assay, compound L20 showed both hematological and solid cancer inhibitory activities. In the flow cytometry, L20 promoted G0/G1 phase cell cycle arrest and apoptosis of K562 cells. 相似文献
167.
168.
169.
170.