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   1036565篇
  免费   77171篇
  国内免费   10680篇
耳鼻咽喉   13551篇
儿科学   30449篇
妇产科学   27668篇
基础医学   146936篇
口腔科学   27134篇
临床医学   91550篇
内科学   202061篇
皮肤病学   20508篇
神经病学   78062篇
特种医学   41240篇
外国民族医学   401篇
外科学   155388篇
综合类   42271篇
现状与发展   29篇
一般理论   259篇
预防医学   74119篇
眼科学   23483篇
药学   79710篇
  120篇
中国医学   9581篇
肿瘤学   59896篇
  2021年   12985篇
  2020年   8895篇
  2019年   11018篇
  2018年   13876篇
  2017年   11619篇
  2016年   11912篇
  2015年   14934篇
  2014年   20047篇
  2013年   26657篇
  2012年   36082篇
  2011年   38334篇
  2010年   24374篇
  2009年   22073篇
  2008年   33640篇
  2007年   35283篇
  2006年   34736篇
  2005年   33672篇
  2004年   31137篇
  2003年   30185篇
  2002年   29057篇
  2001年   44600篇
  2000年   45309篇
  1999年   38720篇
  1998年   11554篇
  1997年   10885篇
  1996年   10290篇
  1995年   9592篇
  1994年   9121篇
  1993年   8288篇
  1992年   29090篇
  1991年   27767篇
  1990年   27118篇
  1989年   26000篇
  1988年   24144篇
  1987年   23659篇
  1986年   22727篇
  1985年   21543篇
  1984年   16134篇
  1983年   13739篇
  1982年   8327篇
  1979年   14759篇
  1978年   10379篇
  1977年   8817篇
  1976年   8314篇
  1975年   9060篇
  1974年   10831篇
  1973年   10289篇
  1972年   9756篇
  1971年   9027篇
  1970年   8683篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
91.
92.
93.
94.
Lessons Learned
  • The combination of trametinib and sorafenib has an acceptable safety profile, albeit at doses lower than approved for monotherapy.
  • Maximum tolerated dose is trametinib 1.5 mg daily and sorafenib 200 mg twice daily.
  • The limited anticancer activity observed in this unselected patient population does not support further exploration of trametinib plus sorafenib in patients with hepatocellular carcinoma.
BackgroundThe RAS/RAF/MEK/ERK signaling pathway is associated with proliferation and progression of hepatocellular carcinoma (HCC). Preclinical data suggest that paradoxical activation of the MAPK pathway may be one of the resistance mechanisms of sorafenib; therefore, we evaluated trametinib plus sorafenib in HCC.MethodsThis was a phase I study with a 3+3 design in patients with treatment‐naïve advanced HCC. The primary objective was safety and tolerability. The secondary objective was clinical efficacy.ResultsA total of 17 patients were treated with three different doses of trametinib and sorafenib. Two patients experienced dose‐limiting toxicity, including grade 4 hypertension and grade 3 elevation of aspartate aminotransferase (AST)/alanine aminotransferase (ALT)/bilirubin over 7 days. Maximum tolerated dose was trametinib 1.5 mg daily and sorafenib 200 mg twice a day. The most common grade 3/4 treatment‐related adverse events were elevated AST (37%) and hypertension (24%). Among 11 evaluable patients, 7 (63.6%) had stable disease with no objective response. The median progression‐free survival (PFS) and overall survival (OS) were 3.7 and 7.8 months, respectively. Phosphorylated‐ERK was evaluated as a pharmacodynamic marker, and sorafenib plus trametinib inhibited phosphorylated‐ERK up to 98.1% (median: 81.2%) in peripheral blood mononuclear cells.ConclusionTrametinib and sorafenib can be safely administered up to trametinib 1.5 mg daily and sorafenib 200 mg twice a day with limited anticancer activity in advanced HCC.  相似文献   
95.
96.
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   
97.
98.
摘要〓目的〓研究四腔水箱在腹外科腔镜电凝线擦拭法清洗消毒中的应用效果。方法〓通过目测法和ATP生物荧光法,对本研究的四腔水箱用于腹外科腔镜电凝线的清洗效果进行评价。结果〓传统治疗碗清洗的206件腔镜电凝线清洗质量合格率为86.4%,四腔水箱清洗的206件腹腔镜电凝线清洗质量合格率为94.6%,差异有统计学意义(P<0.01)。用四腔水箱清洗腔镜电凝线擦拭过程中的护理人员满意度较高。结论〓四腔水箱可提高腹外科腔镜电凝线清洗质量和护理人员满意度。  相似文献   
99.
100.

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   
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