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   914344篇
  免费   65312篇
  国内免费   3484篇
耳鼻咽喉   12604篇
儿科学   29024篇
妇产科学   26358篇
基础医学   128179篇
口腔科学   24906篇
临床医学   76880篇
内科学   185379篇
皮肤病学   19178篇
神经病学   72096篇
特种医学   36933篇
外国民族医学   339篇
外科学   143676篇
综合类   22141篇
现状与发展   7篇
一般理论   249篇
预防医学   65863篇
眼科学   20399篇
药学   65636篇
  24篇
中国医学   2976篇
肿瘤学   50293篇
  2018年   9636篇
  2017年   7768篇
  2016年   8244篇
  2015年   9510篇
  2014年   13323篇
  2013年   20185篇
  2012年   26999篇
  2011年   28720篇
  2010年   17542篇
  2009年   16613篇
  2008年   27055篇
  2007年   28561篇
  2006年   28675篇
  2005年   28096篇
  2004年   26798篇
  2003年   26024篇
  2002年   25469篇
  2001年   41703篇
  2000年   42823篇
  1999年   36517篇
  1998年   10097篇
  1997年   9288篇
  1996年   9177篇
  1995年   8526篇
  1994年   8171篇
  1993年   7640篇
  1992年   28253篇
  1991年   27023篇
  1990年   26444篇
  1989年   25382篇
  1988年   23583篇
  1987年   23186篇
  1986年   22266篇
  1985年   21163篇
  1984年   15813篇
  1983年   13481篇
  1982年   8089篇
  1979年   14591篇
  1978年   10209篇
  1977年   8627篇
  1976年   8148篇
  1975年   8961篇
  1974年   10697篇
  1973年   10183篇
  1972年   9661篇
  1971年   8917篇
  1970年   8584篇
  1969年   8025篇
  1968年   7684篇
  1967年   7086篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
61.
62.
63.
64.
炎症已成为影响肿瘤细胞增殖转移的第七大因素,而白细胞介素-1(IL-1)是炎性微环境的重要因子之一。中医药在治疗肿瘤时具有多途径、多靶点的优势,同时炎性微环境致病特点与现代中医学"癌毒"的理论相吻合。查阅近年中医药调控IL-1家族分子治疗肿瘤机制的文献,对其进行梳理,并做出概括及评价,从中医药主要调控IL-1α、IL-1β和IL-18因子治疗肿瘤展开综述,为中医药更系统化治疗肿瘤提供参考。  相似文献   
65.
66.
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   
67.
68.

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   
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