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   2547336篇
  免费   199098篇
  国内免费   4211篇
耳鼻咽喉   35510篇
儿科学   79320篇
妇产科学   66112篇
基础医学   354247篇
口腔科学   69098篇
临床医学   226972篇
内科学   499096篇
皮肤病学   48742篇
神经病学   216679篇
特种医学   104626篇
外国民族医学   886篇
外科学   390127篇
综合类   58763篇
现状与发展   1篇
一般理论   982篇
预防医学   207341篇
眼科学   58166篇
药学   187440篇
  4篇
中国医学   4994篇
肿瘤学   141539篇
  2018年   45375篇
  2017年   35646篇
  2016年   40083篇
  2015年   24266篇
  2014年   34321篇
  2013年   51596篇
  2012年   75213篇
  2011年   92369篇
  2010年   60136篇
  2009年   51985篇
  2008年   88152篇
  2007年   95385篇
  2006年   74562篇
  2005年   74733篇
  2004年   73394篇
  2003年   72479篇
  2002年   69652篇
  2001年   112867篇
  2000年   117165篇
  1999年   98584篇
  1998年   28103篇
  1997年   25838篇
  1996年   25594篇
  1995年   24767篇
  1994年   23351篇
  1993年   21687篇
  1992年   79500篇
  1991年   76544篇
  1990年   73738篇
  1989年   70945篇
  1988年   65954篇
  1987年   64914篇
  1986年   61430篇
  1985年   58476篇
  1984年   44284篇
  1983年   37713篇
  1982年   22968篇
  1981年   20340篇
  1979年   41390篇
  1978年   29046篇
  1977年   24360篇
  1976年   22902篇
  1975年   23975篇
  1974年   29681篇
  1973年   28053篇
  1972年   26227篇
  1971年   24154篇
  1970年   22779篇
  1969年   21118篇
  1968年   19156篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
151.
152.
153.
154.
Clinical Oral Investigations - The aims of this study are to assess different saliva substitutes for their efficacy to lubricate the oral cavity, and to relate this oral lubrication to the ability...  相似文献   
155.
156.
Background: Dense deposit disease and atypical hemolytic uremic syndrome are often caused by Complement Factor H (CFH) mutations. This study describes the retinal abnormalities in dense deposit disease and, for the first time, atypical haemolytic uremic syndrome. It also reviews our understanding of drusen pathogenesis and their relevance for glomerular disease. Methods: Six individuals with dense deposit disease and one with atypical haemolytic uremic syndrome were studied from 2 to 40 years after presentation. Five had renal transplants. All four who had genetic testing had CFH mutations. Individuals underwent ophthalmological review and retinal photography, and in some cases, optical coherence tomography, and further tests of retinal function. Results: All subjects with dense deposit disease had impaired night vision and retinal drusen or whitish-yellow deposits. Retinal atrophy, pigmentation, and hemorrhage were common. In late disease, peripheral vision was restricted, central vision was distorted, and there were scotoma from sub-retinal choroidal neovascular membranes and atypical serous retinopathy. Drusen were present but less prominent in the young person with atypical uremic syndrome due to a heterozygous CFH mutation. Conclusions: Drusen are common in forms of C3 glomerulopathy caused by compound heterozygous or heterozygous CFH mutations. They are useful diagnostically but also impair vision. Drusen have an identical composition to glomerular deposits. They are also identical to the drusen of age-related macular degeneration, and may respond to the same treatments. Individuals with a C3 glomerulopathy should be assessed ophthalmologically at diagnosis, and monitored regularly for vision-threatening complications.  相似文献   
157.
Obtaining accurate assessment data from adolescents in treatment aids clinical decision making and facilitates more accurate outcome evaluations. However, findings could be biased due to underreported substance use and mental health symptoms. This article compares self-reports of youth in non-White matched client–assessor dyads and those in nonmatched dyads. There were no differences on self-reported substance use, but matched youth reported significantly fewer attention deficit/hyperactivity disorder symptoms versus the comparison group. One possible reason for these findings is the effect of in-group stereotype threat. Future studies should examine the potential effect that in-group stereotyping and perceived racism have on the therapeutic relationship.  相似文献   
158.
Advancing nanomedicines from concept to clinic requires integration of new science with traditional pharmaceutical development. The medical and commercial success of nanomedicines is greatly facilitated when those charged with developing nanomedicines are cognizant of the unique opportunities and technical challenges that these products present. These individuals must also be knowledgeable about the processes of clinical and product development, including regulatory considerations, to maximize the odds for successful product registration. This article outlines these topics with a goal to accelerate the combination of academic innovation with collaborative industrial scientists who understand pharmaceutical development and regulatory approval requirements—only together can they realize the full potential of nanomedicines for patients.  相似文献   
159.
160.
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