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   3255486篇
  免费   245499篇
  国内免费   5686篇
耳鼻咽喉   44781篇
儿科学   106482篇
妇产科学   90010篇
基础医学   474738篇
口腔科学   89919篇
临床医学   297089篇
内科学   628700篇
皮肤病学   73088篇
神经病学   260739篇
特种医学   121892篇
外国民族医学   905篇
外科学   488591篇
综合类   72220篇
现状与发展   15篇
一般理论   1203篇
预防医学   258250篇
眼科学   75972篇
药学   239496篇
  11篇
中国医学   6865篇
肿瘤学   175705篇
  2021年   25857篇
  2019年   26692篇
  2018年   37034篇
  2017年   27884篇
  2016年   31453篇
  2015年   35334篇
  2014年   50185篇
  2013年   75318篇
  2012年   103174篇
  2011年   110133篇
  2010年   65237篇
  2009年   61709篇
  2008年   102583篇
  2007年   109083篇
  2006年   110262篇
  2005年   107071篇
  2004年   102597篇
  2003年   98429篇
  2002年   95050篇
  2001年   150558篇
  2000年   154305篇
  1999年   129417篇
  1998年   37889篇
  1997年   33500篇
  1996年   33552篇
  1995年   31684篇
  1994年   29255篇
  1993年   27463篇
  1992年   99560篇
  1991年   96713篇
  1990年   94000篇
  1989年   90559篇
  1988年   83423篇
  1987年   81448篇
  1986年   76342篇
  1985年   73281篇
  1984年   55031篇
  1983年   46768篇
  1982年   28167篇
  1979年   50180篇
  1978年   35629篇
  1977年   29688篇
  1976年   28347篇
  1975年   30060篇
  1974年   36312篇
  1973年   34597篇
  1972年   32603篇
  1971年   30534篇
  1970年   28420篇
  1969年   26867篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
83.
We report on a child with several café au lait spots in association with a lumbar lipomeningomyelocele as an apparently new association. Cutaneous markers, the identification of which plays a crucial role in the early diagnosis and management of spinal malformations, can accompany occult spinal dysraphism. Herein we report a case of lumbar lipomeningomyelocele associated with an overlying café au lait spot that served as a marker of occult spinal dysraphism. The patient also had segmental café au lait spots on the face, making the association unique.  相似文献   
84.
85.
86.
Dosage form is a mean used for the delivery of drug to a living body. In order to get the desired effect the drug should be delivered to its site of action at such rate and concentration to achieve the maximum therapeutic effect and minimum adverse effect. Since oral route is still widely accepted route but having a common drawback of difficulty in swallowing of tablets and capsules. Therefore a lot of research has been done on novel drug delivery systems. This review is about oral dispersible tablets a novel approach in drug delivery systems that are now a day''s more focused in formulation world, and laid a new path that, helped the patients to build their compliance level with the therapy, also reduced the cost and ease the administration especially in case of pediatrics and geriatrics. Quick absorption, rapid onset of action and reduction in drug loss properties are the basic advantages of this dosage form.  相似文献   
87.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  相似文献   
88.
89.
Bipolar disorder (BD) is a common psychiatric mood disorder affecting more than 1-2% of the general population of different European countries. Unfortunately, there is no objective laboratory-based test to aid BD diagnosis or monitor its progression, and little is known about the molecular basis of BD. Here, we performed a comparative proteomic study to identify differentially expressed plasma proteins in various BD mood states (depressed BD, manic BD, and euthymic BD) relative to healthy controls. A total of 10 euthymic BD, 20 depressed BD, 15 manic BD, and 20 demographically matched healthy control subjects were recruited. Seven high-abundance proteins were immunodepleted in plasma samples from the 4 experimental groups, which were then subjected to proteome-wide expression profiling by two-dimensional electrophoresis and matrix-assisted laser desorption/ionization-time-of-flight/time-of-flight tandem mass spectrometry. Proteomic results were validated by immunoblotting and bioinformatically analyzed using MetaCore. From a total of 32 proteins identified with 1.5-fold changes in expression compared with healthy controls, 16 proteins were perturbed in BD independent of mood state, while 16 proteins were specifically associated with particular BD mood states. Two mood-independent differential proteins, apolipoprotein (Apo) A1 and Apo L1, suggest that BD pathophysiology may be associated with early perturbations in lipid metabolism. Moreover, down-regulation of one mood-dependent protein, carbonic anhydrase 1 (CA-1), suggests it may be involved in the pathophysiology of depressive episodes in BD. Thus, BD pathophysiology may be associated with early perturbations in lipid metabolism that are independent of mood state, while CA-1 may be involved in the pathophysiology of depressive episodes.  相似文献   
90.
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