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   2589689篇
  免费   184630篇
  国内免费   7576篇
耳鼻咽喉   34329篇
儿科学   85222篇
妇产科学   71579篇
基础医学   363841篇
口腔科学   69750篇
临床医学   234604篇
内科学   515937篇
皮肤病学   62465篇
神经病学   213541篇
特种医学   99952篇
外国民族医学   736篇
外科学   386763篇
综合类   50406篇
现状与发展   5篇
一般理论   968篇
预防医学   196264篇
眼科学   56680篇
药学   188094篇
  8篇
中国医学   5332篇
肿瘤学   145419篇
  2021年   20029篇
  2019年   20644篇
  2018年   29329篇
  2017年   22622篇
  2016年   26267篇
  2015年   29541篇
  2014年   40488篇
  2013年   60470篇
  2012年   80298篇
  2011年   84590篇
  2010年   51049篇
  2009年   49195篇
  2008年   79126篇
  2007年   83951篇
  2006年   85663篇
  2005年   81824篇
  2004年   78829篇
  2003年   76137篇
  2002年   73422篇
  2001年   128450篇
  2000年   131378篇
  1999年   110549篇
  1998年   31275篇
  1997年   27945篇
  1996年   28228篇
  1995年   27395篇
  1994年   25077篇
  1993年   23432篇
  1992年   85181篇
  1991年   81592篇
  1990年   78806篇
  1989年   76080篇
  1988年   69487篇
  1987年   68031篇
  1986年   63571篇
  1985年   60534篇
  1984年   44955篇
  1983年   37952篇
  1982年   22460篇
  1981年   19986篇
  1979年   38971篇
  1978年   27453篇
  1977年   23257篇
  1976年   21499篇
  1975年   22819篇
  1974年   26796篇
  1973年   25373篇
  1972年   23756篇
  1971年   21961篇
  1970年   20193篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
141.
142.
143.
144.
145.
The special interest group on sensitive skin of the International Forum for the Study of Itch previously defined sensitive skin as a syndrome defined by the occurrence of unpleasant sensations (stinging, burning, pain, pruritus and tingling sensations) in response to stimuli that normally should not provoke such sensations. This additional paper focuses on the pathophysiology and the management of sensitive skin. Sensitive skin is not an immunological disorder but is related to alterations of the skin nervous system. Skin barrier abnormalities are frequently associated, but there is no cause and direct relationship. Further studies are needed to better understand the pathophysiology of sensitive skin – as well as the inducing factors. Avoidance of possible triggering factors and the use of well-tolerated cosmetics, especially those containing inhibitors of unpleasant sensations, might be suggested for patients with sensitive skin. The role of psychosocial factors, such as stress or negative expectations, might be relevant for subgroups of patients. To date, there is no clinical trial supporting the use of topical or systemic drugs in sensitive skin. The published data are not sufficient to reach a consensus on sensitive skin management. In general, patients with sensitive skin require a personalized approach, taking into account various biomedical, neural and psychosocial factors affecting sensitive skin.  相似文献   
146.
Treatment decisions in patients with metastatic bone disease rely on accurate survival estimation. We developed the original PATHFx models using expensive, proprietary software and now seek to provide a more cost-effective solution. Using open-source machine learning software to create PATHFx version 2.0, we asked whether PATHFx 2.0 could be created using open-source methods and externally validated in two unique patient populations. The training set of a well-characterized, database records of 189 patients and the bnlearn package within R Version 3.5.1 (R Foundation for Statistical Computing), was used to establish a series of Bayesian belief network models designed to predict survival at 1, 3, 6, 12, 18, and 24 months. Each was externally validated in both a Scandinavian (n = 815 patients) and a Japanese (n = 261 patients) data set. Brier scores and receiver operating characteristic curves to assessed discriminatory ability. Decision curve analysis (DCA) evaluated whether models should be used clinically. DCA showed that the model should be used clinically at all time points in the Scandinavian data set. For the 1-month time point, DCA of the Japanese data set suggested to expect better outcomes assuming all patients will survive greater than 1 month. Brier scores for each curve demonstrate that the models are accurate at each time point. Statement of Clinical Significance: we successfully transitioned to PATHFx 2.0 using open-source software and externally validated it in two unique patient populations, which can be used as a cost-effective option to guide surgical decisions in patients with metastatic bone disease.  相似文献   
147.
148.
We evaluated RNA stability of Ebola virus in EDTA blood and urine samples collected from infected patients and stored in West Africa’s environmental conditions. In blood, RNA was stable for at least 18 days when initial cycle threshold values were <30, but in urine, RNA degradation occurred more quickly.  相似文献   
149.
150.
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