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   1200122篇
  免费   80593篇
  国内免费   2729篇
耳鼻咽喉   14465篇
儿科学   42016篇
妇产科学   32400篇
基础医学   166215篇
口腔科学   29662篇
临床医学   107701篇
内科学   229631篇
皮肤病学   24204篇
神经病学   98477篇
特种医学   47652篇
外国民族医学   306篇
外科学   179804篇
综合类   26745篇
一般理论   425篇
预防医学   99348篇
眼科学   26023篇
药学   83551篇
  3篇
中国医学   2722篇
肿瘤学   72094篇
  2018年   32170篇
  2017年   25262篇
  2016年   28580篇
  2015年   12332篇
  2014年   16307篇
  2013年   24526篇
  2012年   38287篇
  2011年   53574篇
  2010年   37669篇
  2009年   29735篇
  2008年   49727篇
  2007年   53736篇
  2006年   34294篇
  2005年   34492篇
  2004年   34882篇
  2003年   34530篇
  2002年   31539篇
  2001年   47526篇
  2000年   48671篇
  1999年   40779篇
  1998年   11811篇
  1997年   10663篇
  1996年   10581篇
  1995年   10202篇
  1994年   9432篇
  1993年   8811篇
  1992年   32500篇
  1991年   31751篇
  1990年   31314篇
  1989年   30133篇
  1988年   27413篇
  1987年   27517篇
  1986年   25591篇
  1985年   24778篇
  1984年   18610篇
  1983年   15712篇
  1982年   9531篇
  1981年   8545篇
  1979年   16985篇
  1978年   12330篇
  1977年   10424篇
  1976年   9848篇
  1975年   10254篇
  1974年   12419篇
  1973年   11910篇
  1972年   10949篇
  1971年   10155篇
  1970年   9427篇
  1969年   8783篇
  1968年   8142篇
排序方式: 共有10000条查询结果,搜索用时 343 毫秒
61.
62.
63.
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   
64.
65.

Background

Arterial vascular anomalies in patients undergoing kidney transplantation (KT) are correlated with a higher incidence of early surgical complications, potentially causing graft loss. Arterial reconstruction allows patients to overcome these surgical challenges, thus minimizing the risk of poor outcomes. The aim of the present study is to retrospectively investigate the safety and effectiveness of the multiple arterial reconstruction technique with a Teflon patch in case of an unavailable aortic patch: to do so, surgical complications, graft function, and patient survival were evaluated.

Methods

During the period January 2009 to August 2016, 202 adult deceased-donor KTs were performed at our center. Group A (n = 27; reconstruction of multiple arteries) and Group B (n = 175; control group) were compared.

Results

No differences were observed between the 2 groups in terms of early postoperative course, with no vascular complication observed in Group A. No vascular patch infections were reported, nor longer cold ischemia time rates. Similarly, long-term survival rates were similar between the 2 groups.

Conclusions

The Teflon-patch arterial reconstruction technique appears to be safe and effective, with an acceptable balance of benefits and potential risks of using a prosthetic material. Studies based on larger series are needed to further validate this approach.  相似文献   
66.
67.
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   
68.
69.
70.
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