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   1358854篇
  免费   97213篇
  国内免费   3048篇
耳鼻咽喉   20040篇
儿科学   40721篇
妇产科学   39074篇
基础医学   190594篇
口腔科学   40692篇
临床医学   114523篇
内科学   268282篇
皮肤病学   30871篇
神经病学   108195篇
特种医学   54666篇
外国民族医学   435篇
外科学   212151篇
综合类   31219篇
现状与发展   6篇
一般理论   438篇
预防医学   92805篇
眼科学   31793篇
药学   101604篇
  3篇
中国医学   3021篇
肿瘤学   77982篇
  2018年   12298篇
  2016年   11010篇
  2015年   12387篇
  2014年   17375篇
  2013年   25990篇
  2012年   34179篇
  2011年   36169篇
  2010年   21443篇
  2009年   20874篇
  2008年   34723篇
  2007年   37902篇
  2006年   38485篇
  2005年   37268篇
  2004年   36305篇
  2003年   35185篇
  2002年   34746篇
  2001年   64242篇
  2000年   65997篇
  1999年   56015篇
  1998年   14964篇
  1997年   13674篇
  1996年   13183篇
  1995年   12439篇
  1994年   11660篇
  1992年   43200篇
  1991年   41690篇
  1990年   40923篇
  1989年   39924篇
  1988年   37348篇
  1987年   36781篇
  1986年   35244篇
  1985年   33430篇
  1984年   25069篇
  1983年   21247篇
  1982年   12773篇
  1981年   11675篇
  1979年   24131篇
  1978年   17207篇
  1977年   14993篇
  1976年   13461篇
  1975年   15411篇
  1974年   18243篇
  1973年   17714篇
  1972年   16933篇
  1971年   15859篇
  1970年   15051篇
  1969年   14488篇
  1968年   13576篇
  1967年   12144篇
  1966年   11350篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.

Background and objectives

A prompt and effective management of trauma patient is necessary. The aim of this case report is to highlight the importance of intraoperative echocardiography as a useful tool in patients suffering from refractory hemodynamic instability no otherwise explained.

Case report

A 41 year‐old woman suffered a car accident. At the emergency department, no abnormalities were found in ECG or chest X‐ray. Abdominal ultrasound revealed the presence of abdominal free liquid and the patient was submitted to urgent exploratory laparotomy. Nevertheless, she persisted suffering arterial hypotension and metabolic acidosis. Looking for the reason of her hemodynamic instability, intraoperative transthoracic echocardiography was performed, finding out the presence of pericardial effusion. Once the cardiac surgeon extracted pericardial clots, patient's situation improved clinically and analytically.

Conclusion

Every anesthesiologist should be able to use the intraoperative echocardiography as an effective tool in order to establish the appropriate measures to promote the survival of patients suffering severe trauma.  相似文献   
22.
23.
24.
25.
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   
26.
27.
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   
28.
Finasteride is standard medical treatment for androgenetic alopecia; however, no large studies with 5 years or more of follow up have been performed in Japan. The authors followed Japanese men with androgenetic alopecia treated with finasteride for 5 years to evaluate long‐term treatment efficacy. Of 903 men treated with finasteride (1 mg/day), 801 patients were evaluated over 5 years by modified global photographic assessment. Although the proportion of improvement was high (99.4%), modified global photographic assessment scores after 5 years of treatment were lower in patients with more advanced disease as measured by the modified Norwood–Hamilton scale. After separating patients into “sufficient” and “insufficient” efficacy groups according to the modified global photographic assessment score after 5 years (scores ≥6 and <6, respectively), multivariate analysis showed that independent risk factors of insufficient efficacy were age at start of treatment of 40 years or more (P = 0.021) and classification on the modified Norwood–Hamilton scale (P < 0.001), whereas presence of stress at start of treatment was a negative predictor (P = 0.025). In conclusion, continuous finasteride treatment for 5 years improved androgenetic alopecia with sustained effect among Japanese. Younger age and less advanced disease at start of treatment were the key predictors of higher finasteride efficacy.  相似文献   
29.
30.
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