首页 | 官方网站   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   2437461篇
  免费   188160篇
  国内免费   4030篇
医药卫生   2629651篇
  2018年   25378篇
  2017年   19736篇
  2016年   21388篇
  2015年   24788篇
  2014年   34171篇
  2013年   50370篇
  2012年   69540篇
  2011年   73077篇
  2010年   42453篇
  2009年   40243篇
  2008年   68621篇
  2007年   72471篇
  2006年   73072篇
  2005年   71288篇
  2004年   69643篇
  2003年   66389篇
  2002年   63667篇
  2001年   118576篇
  2000年   122850篇
  1999年   103804篇
  1998年   27127篇
  1997年   24425篇
  1996年   24367篇
  1995年   23355篇
  1994年   21831篇
  1993年   20481篇
  1992年   83366篇
  1991年   80632篇
  1990年   78486篇
  1989年   76191篇
  1988年   70321篇
  1987年   69050篇
  1986年   65292篇
  1985年   63073篇
  1984年   46214篇
  1983年   39651篇
  1982年   22373篇
  1981年   19850篇
  1979年   43139篇
  1978年   29529篇
  1977年   25038篇
  1976年   23002篇
  1975年   24788篇
  1974年   30089篇
  1973年   28901篇
  1972年   26798篇
  1971年   25224篇
  1970年   23596篇
  1969年   22162篇
  1968年   20231篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
Quality of Life Research - The COVID-19 pandemic might add to the stressors experienced by people living with rheumatic diseases. This study aimed to examine rheumatic patients’ functional...  相似文献   
2.
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   
3.
4.
5.
6.
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   
7.
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-23

京公网安备 11010802026262号