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   3386521篇
  免费   297688篇
  国内免费   13387篇
医药卫生   3697596篇
  2021年   49211篇
  2020年   35024篇
  2019年   58056篇
  2018年   71149篇
  2017年   53858篇
  2016年   59475篇
  2015年   73595篇
  2014年   107788篇
  2013年   172971篇
  2012年   91803篇
  2011年   91685篇
  2010年   116552篇
  2009年   121145篇
  2008年   79661篇
  2007年   83059篇
  2006年   93725篇
  2005年   89274篇
  2004年   91391篇
  2003年   82167篇
  2002年   72226篇
  2001年   109330篇
  2000年   102987篇
  1999年   100472篇
  1998年   60266篇
  1997年   57658篇
  1996年   55525篇
  1995年   56311篇
  1994年   50682篇
  1993年   47205篇
  1992年   72396篇
  1991年   69776篇
  1990年   66204篇
  1989年   64642篇
  1988年   59740篇
  1987年   58611篇
  1986年   55004篇
  1985年   55037篇
  1984年   49517篇
  1983年   44974篇
  1982年   41444篇
  1981年   39221篇
  1980年   36723篇
  1979年   40457篇
  1978年   35391篇
  1977年   32257篇
  1976年   29662篇
  1975年   28631篇
  1974年   29426篇
  1973年   28379篇
  1972年   26430篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
12.
Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient.  相似文献   
13.
14.
The Extracellular Vesicle Flow Cytometry Working Group ( http://www.evflowcytometry.org ) is formed by members of the International Society for Extracellular Vesicles (ISEV), the International Society for Advancement of Cytometry (ISAC), and the International Society on Thrombosis and Haemostasis (ISTH). This working group of flow cytometry experts develops guidelines for best practices regarding flow cytometry detection of extracellular vesicles. To improve rigor and standardization, this working group published a framework outlining the minimal information to report about a flow cytometry experiment on extracellular vesicles (MIFlowCyt-EV) in the Journal of Extracellular Vesicles, the ISEV journal, in 2020. In parallel, an article explaining MIFlowCyt-EV was published in Cytometry Part A, one of the ISAC journals, and now will be introduced to the ISTH as an SSC Communication in the Journal of Thrombosis and Haemostasis. The goal of this SSC Communication is to explain why flow cytometry is becoming the instrument of choice to characterize single extracellular vesicles, the obstacles that have been identified and (mostly) overcome by developing procedures to calibrate flow cytometers, and the relevance of reporting minimal information to improve reliability and reproducibility of experiments in which flow cytometers are used for characterization of extracellular vesicles.  相似文献   
15.
16.
基于国家深化高等院校课程建设的新时代视域,提升课程质量成为高校教育教学发展的重要任务。地方医学院校作为基层卫生人才的培养摇篮,构建科学合理的课程质量监控体系愈发迫切。本文分析了我国高等院校课程质量监控体系存在的问题,结合地方医学院校办学特点和广州医科大学工作实践,探索构建了集“多样化监控方法、全维度监控指标、闭环式反馈机制、多层级文化建设”为一体的课程质量监控体系,为同类院校提供实际参考。  相似文献   
17.
18.
19.
20.
In 2019, the scientists who discovered how cells sense and adapt to oxygen availability were awarded the Nobel Prize. This elegant sensing pathway is conserved throughout evolution, and it underpins the physiology and pathology that we, as clinicians in anaesthesia and critical care, encounter on a daily basis. The purpose of this review is to bring hypoxia-inducible factor, and the oxygen-sensing pathway as a whole, to the wider clinical community. We describe how this unifying mechanism was discovered, and how it orchestrates diverse changes such as erythropoiesis, ventilatory acclimatisation, pulmonary vascular remodelling and altered metabolism. We explore the lessons learnt from genetic disorders of oxygen sensing, and the wider implications in evolution of all animal species, including our own. Finally, we explain how this pathway is relevant to our clinical practice, and how it is being manipulated in new treatments for conditions such as cancer, anaemia and pulmonary hypertension.  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-23

京公网安备 11010802026262号