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   3367623篇
  免费   247482篇
  国内免费   8664篇
耳鼻咽喉   46681篇
儿科学   112501篇
妇产科学   93379篇
基础医学   474155篇
口腔科学   92772篇
临床医学   305833篇
内科学   662623篇
皮肤病学   78698篇
神经病学   273890篇
特种医学   130701篇
外国民族医学   1282篇
外科学   506978篇
综合类   69904篇
现状与发展   6篇
一般理论   1222篇
预防医学   258223篇
眼科学   76239篇
药学   248521篇
  9篇
中国医学   6945篇
肿瘤学   183207篇
  2019年   26154篇
  2018年   36948篇
  2017年   28272篇
  2016年   32519篇
  2015年   36780篇
  2014年   50579篇
  2013年   76308篇
  2012年   102177篇
  2011年   108169篇
  2010年   65208篇
  2009年   62280篇
  2008年   101240篇
  2007年   107691篇
  2006年   109189篇
  2005年   105044篇
  2004年   101584篇
  2003年   98063篇
  2002年   94934篇
  2001年   161407篇
  2000年   165856篇
  1999年   140296篇
  1998年   40266篇
  1997年   35818篇
  1996年   36002篇
  1995年   34725篇
  1994年   32181篇
  1993年   30161篇
  1992年   110154篇
  1991年   106394篇
  1990年   103343篇
  1989年   99772篇
  1988年   91564篇
  1987年   89862篇
  1986年   84070篇
  1985年   80333篇
  1984年   60055篇
  1983年   50862篇
  1982年   29922篇
  1981年   26996篇
  1979年   53339篇
  1978年   37503篇
  1977年   31981篇
  1976年   29658篇
  1975年   31702篇
  1974年   37335篇
  1973年   35576篇
  1972年   33274篇
  1971年   30667篇
  1970年   28573篇
  1969年   26934篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
92.
93.
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   
94.
95.
Pediatric trachyonychia is an acquired nail disease that can cause distress to families. It is a poorly understood disease, and long‐term follow‐up data are lacking. We present an institutional review of 11 children with isolated pediatric trachyonychia followed over time. Children with the diagnosis of pediatric trachyonychia were identified and invited to participate. Pictures were taken on follow‐up and a questionnaire was answered. Exclusion criteria include having another diagnosis at the initial visit that causes nail dystrophy. Eleven patients with the diagnosis of pediatric trachyonychia were available for follow‐up. The mean age of appearance was 2.7 years (range 2–7 yrs) and the average follow‐up was 66 months (range 10–126 mos). Nine patients were treated with potent topical corticosteroids, one used only petrolatum, and one took vitamin supplements. One patient was found to have an additional skin and hair diagnosis of alopecia areata on follow‐up. On follow‐up, 82% noted improvement of the nails, whereas 18% noted no change. A majority of cases of pediatric trachyonychia are isolated and improve with time, regardless of treatment.  相似文献   
96.
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   
97.
98.
99.
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   
100.
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