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   2007934篇
  免费   152969篇
  国内免费   2961篇
耳鼻咽喉   27168篇
儿科学   66008篇
妇产科学   55750篇
基础医学   301125篇
口腔科学   57067篇
临床医学   179537篇
内科学   383089篇
皮肤病学   43389篇
神经病学   155379篇
特种医学   79945篇
外国民族医学   523篇
外科学   304512篇
综合类   45445篇
现状与发展   4篇
一般理论   631篇
预防医学   153420篇
眼科学   45958篇
药学   153486篇
  3篇
中国医学   3702篇
肿瘤学   107723篇
  2018年   19151篇
  2016年   16680篇
  2015年   19065篇
  2014年   26134篇
  2013年   39498篇
  2012年   54517篇
  2011年   58420篇
  2010年   34233篇
  2009年   32125篇
  2008年   55209篇
  2007年   58978篇
  2006年   59375篇
  2005年   57466篇
  2004年   56582篇
  2003年   54330篇
  2002年   53047篇
  2001年   91566篇
  2000年   94421篇
  1999年   79794篇
  1998年   21759篇
  1997年   19520篇
  1996年   18318篇
  1995年   18924篇
  1994年   17721篇
  1993年   16836篇
  1992年   65823篇
  1991年   65729篇
  1990年   64705篇
  1989年   62786篇
  1988年   58312篇
  1987年   57598篇
  1986年   54450篇
  1985年   52677篇
  1984年   39279篇
  1983年   33814篇
  1982年   19355篇
  1981年   17380篇
  1979年   37504篇
  1978年   26157篇
  1977年   21805篇
  1976年   21165篇
  1975年   22993篇
  1974年   27640篇
  1973年   26566篇
  1972年   24441篇
  1971年   23084篇
  1970年   21294篇
  1969年   19894篇
  1968年   18378篇
  1967年   16580篇
排序方式: 共有10000条查询结果,搜索用时 250 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.
Journal of Behavioral Medicine - Evidence supports the use of graphic warnings to educate the public about the health harms of smoking and suggests warnings eliciting negative emotional responses...  相似文献   
6.
The adrenal cortex gives rise to a biologically heterogenous group of neoplasms, each with a distinct morphology, antigen expression and molecular profile. Adrenal cortical adenomas have excellent prognosis and are usually cured by surgical resection alone, while adrenal cortical carcinomas are very aggressive tumors with a poor prognosis regardless of therapy. These tumors are rare and often challenging for a pathologist to diagnose, as significant overlap exists between benign and malignant lesions in some cases. In this review, we attempt to summarize most important histologic and clinical features of adrenal cortical adenomas and carcinomas, clarify the use of different grading systems, the use of special stains and the differential diagnosis for practicing pathologists. Most relevant hereditary syndromes associated with adrenal cortical tumors are listed. Updates in molecular alterations in adrenal cortical neoplasms and hyperplastic diseases as well as their clinical significance and potential therapeutic implications are also discussed.  相似文献   
7.
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   
8.
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