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   1708797篇
  免费   141218篇
  国内免费   3078篇
耳鼻咽喉   23032篇
儿科学   55774篇
妇产科学   48234篇
基础医学   241603篇
口腔科学   49588篇
临床医学   151659篇
内科学   336747篇
皮肤病学   35496篇
神经病学   139784篇
特种医学   68944篇
外国民族医学   474篇
外科学   261381篇
综合类   41316篇
现状与发展   4篇
一般理论   702篇
预防医学   133390篇
眼科学   38844篇
药学   128963篇
  5篇
中国医学   3118篇
肿瘤学   94035篇
  2018年   17133篇
  2016年   14708篇
  2015年   17173篇
  2014年   23807篇
  2013年   36263篇
  2012年   49600篇
  2011年   52235篇
  2010年   30601篇
  2009年   29249篇
  2008年   49796篇
  2007年   52557篇
  2006年   52913篇
  2005年   51731篇
  2004年   50819篇
  2003年   48573篇
  2002年   47540篇
  2001年   76693篇
  2000年   79182篇
  1999年   67508篇
  1998年   19045篇
  1997年   17350篇
  1996年   17330篇
  1995年   16994篇
  1994年   15893篇
  1993年   15028篇
  1992年   56075篇
  1991年   54455篇
  1990年   53160篇
  1989年   51418篇
  1988年   47798篇
  1987年   47143篇
  1986年   44882篇
  1985年   43532篇
  1984年   32783篇
  1983年   28253篇
  1982年   17071篇
  1981年   15372篇
  1980年   14350篇
  1979年   30946篇
  1978年   21588篇
  1977年   18265篇
  1976年   17110篇
  1975年   17947篇
  1974年   21869篇
  1973年   21052篇
  1972年   19091篇
  1971年   18019篇
  1970年   16523篇
  1969年   15452篇
  1968年   14122篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Kinase alterations are increasingly recognised as oncogenic drivers in mesenchymal tumours. Infantile fibrosarcoma and the related renal tumour, congenital mesoblastic nephroma, were among the first solid tumours shown to harbour recurrent tyrosine kinase fusions, with the canonical ETV6::NTRK3 fusion identified more than 20 years ago. Although targeted testing has long been used in diagnosis, the advent of more robust sequencing techniques has driven the discovery of kinase alterations in an array of mesenchymal tumours. As our ability to identify these genetic alterations has improved, as has our recognition and understanding of the tumours that harbour these alterations. Specifically, this study will focus upon mesenchymal tumours harbouring NTRK or other kinase alterations, including tumours with an infantile fibrosarcoma-like appearance, spindle cell tumours resembling lipofibromatosis or peripheral nerve sheath tumours and those occurring in adults with a fibrosarcoma-like appearance. As publications describing the histology of these tumours increase so, too, do the variety kinase alterations reported, now including NTRK1/2/3, RET, MET, RAF1, BRAF, ALK, EGFR and ABL1 fusions or alterations. To date, these tumours appear locally aggressive and rarely metastatic, without a clear link between traditional features used in histological grading (e.g. mitotic activity, necrosis) and outcome. However, most of these tumours are amenable to new targeted therapies, making their recognition of both diagnostic and therapeutic import. The goal of this study is to review the clinicopathological features of tumours with NTRK and other tyrosine kinase alterations, discuss the most common differential diagnoses and provide recommendations for molecular confirmation with associated treatment implications.  相似文献   
2.
3.
4.
5.
Bone mineral density (BMD) is a highly heritable predictor of osteoporotic fracture. GWAS have identified hundreds of loci influencing BMD, but few have been functionally analyzed. In this study, we show that SNPs within a BMD locus on chromosome 14q32.32 alter splicing and expression of PAR-1a/microtubule affinity regulating kinase 3 (MARK3), a conserved serine/threonine kinase known to regulate bioenergetics, cell division, and polarity. Mice lacking Mark3 either globally or selectively in osteoblasts have increased bone mass at maturity. RNA profiling from Mark3-deficient osteoblasts suggested changes in the expression of components of the Notch signaling pathway. Mark3-deficient osteoblasts exhibited greater matrix mineralization compared with controls that was accompanied by reduced Jag1/Hes1 expression and diminished downstream JNK signaling. Overexpression of Jag1 in Mark3-deficient osteoblasts both in vitro and in vivo normalized mineralization capacity and bone mass, respectively. Together, these findings reveal a mechanism whereby genetically regulated alterations in Mark3 expression perturb cell signaling in osteoblasts to influence bone mass.  相似文献   
6.
7.
8.
Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome.  相似文献   
9.
10.
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