首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   402733篇
  免费   16263篇
  国内免费   990篇
耳鼻咽喉   3609篇
儿科学   12430篇
妇产科学   7314篇
基础医学   45219篇
口腔科学   5818篇
临床医学   35645篇
内科学   78980篇
皮肤病学   3855篇
神经病学   39411篇
特种医学   18550篇
外国民族医学   13篇
外科学   64528篇
综合类   4816篇
现状与发展   1篇
一般理论   177篇
预防医学   33949篇
眼科学   8160篇
药学   24619篇
  1篇
中国医学   941篇
肿瘤学   31950篇
  2023年   1233篇
  2022年   2165篇
  2021年   5349篇
  2020年   3056篇
  2019年   5095篇
  2018年   27097篇
  2017年   21091篇
  2016年   23576篇
  2015年   6610篇
  2014年   9109篇
  2013年   11978篇
  2012年   23926篇
  2011年   38109篇
  2010年   28155篇
  2009年   20299篇
  2008年   34476篇
  2007年   37394篇
  2006年   16685篇
  2005年   18071篇
  2004年   18327篇
  2003年   17915篇
  2002年   15530篇
  2001年   2218篇
  2000年   1845篇
  1999年   2185篇
  1998年   2979篇
  1997年   2418篇
  1996年   2016篇
  1995年   1863篇
  1994年   1633篇
  1993年   1562篇
  1992年   1033篇
  1991年   1020篇
  1990年   914篇
  1989年   828篇
  1988年   736篇
  1987年   668篇
  1986年   679篇
  1985年   725篇
  1984年   943篇
  1983年   818篇
  1982年   1062篇
  1981年   967篇
  1980年   879篇
  1979年   469篇
  1978年   530篇
  1977年   451篇
  1976年   430篇
  1975年   323篇
  1974年   338篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate the long-term safety and efficacy of intrastromal bevacizumab for treatment of deep corneal neovascularization in...  相似文献   
22.
23.
DNA methylation at CpG dinucleotides is an important epigenetic regulator common to virtually all mammalian cell types, but recent evidence indicates that during early postnatal development neuronal genomes also accumulate uniquely high levels of two alternative forms of methylation, non-CpG methylation and hydroxymethylation. Here we discuss the distinct landscape of DNA methylation in neurons, how it is established, and how it might affect the binding and function of protein readers of DNA methylation. We review studies of one critical reader of DNA methylation in the brain, the Rett syndrome protein methyl CpG-binding protein 2 (MeCP2), and discuss how differential binding affinity of MeCP2 for non-CpG and hydroxymethylation may affect the function of this methyl-binding protein in the nervous system.  相似文献   
24.
25.
26.
27.
28.
29.
Farnesyltransferase (FTase) is one of the prenyltransferase family enzymes that catalyse the transfer of 15-membered isoprenoid (farnesyl) moiety to the cysteine of CAAX motif-containing proteins including Rho and Ras family of G proteins. Inhibitors of FTase act as drugs for cancer, malaria, progeria and other diseases. In the present investigation, we have developed two structure-based pharmacophore models from protein–ligand complex (3E33 and 3E37) obtained from the protein data bank. Molecular dynamics (MD) simulations were performed on the complexes, and different conformers of the same complex were generated. These conformers were undergone protein–ligand interaction fingerprint (PLIF) analysis, and the fingerprint bits have been used for structure-based pharmacophore model development. The PLIF results showed that Lys164, Tyr166, TrpB106 and TyrB361 are the major interacting residues in both the complexes. The RMSD and RMSF analyses on the MD-simulated systems showed that the absence of FPP in the complex 3E37 has significant effect in the conformational changes of the ligands. During this conformational change, some interactions between the protein and the ligands are lost, but regained after some simulations (after 2 ns). The structure-based pharmacophore models showed that the hydrophobic and acceptor contours are predominantly present in the models. The pharmacophore models were validated using reference compounds, which significantly identified as HITs with smaller RMSD values. The developed structure-based pharmacophore models are significant, and the methodology used in this study is novel from the existing methods (the original X-ray crystallographic coordination of the ligands is used for the model building). In our study, along with the original coordination of the ligand, different conformers of the same complex (protein–ligand) are used. It concluded that the developed methodology is significant for the virtual screening of novel molecules on different targets.  相似文献   
30.
This paper takes a somewhat slant perspective on flourishing and care in the context of suffering, death and dying, arguing that care in this context consists principally of ‘acts of work and courage that enable flourishing’. Starting with the perception that individuals, society and health care professionals have become dulled to death and the process of dying in Western advanced health systems, it suggests that for flourishing to occur, both of these aspects of life need to be faced more directly. The last days of life need to be ‘undulled’. Reflections upon the experiences of the author as carer and daughter in the face of her mother’s experience of death are used as basis for making suggestions about how care systems and professionals might better assist people in dealing with ‘the most grown up thing’ humans ever do, which is to die.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号