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   25580篇
  免费   1883篇
  国内免费   226篇
耳鼻咽喉   385篇
儿科学   1322篇
妇产科学   629篇
基础医学   1876篇
口腔科学   432篇
临床医学   2802篇
内科学   6062篇
皮肤病学   439篇
神经病学   1332篇
特种医学   900篇
外科学   5249篇
综合类   461篇
一般理论   3篇
预防医学   1379篇
眼科学   1213篇
药学   1579篇
  1篇
中国医学   71篇
肿瘤学   1554篇
  2023年   248篇
  2022年   302篇
  2021年   817篇
  2020年   495篇
  2019年   644篇
  2018年   827篇
  2017年   657篇
  2016年   674篇
  2015年   636篇
  2014年   1002篇
  2013年   1280篇
  2012年   1572篇
  2011年   1451篇
  2010年   1069篇
  2009年   993篇
  2008年   1108篇
  2007年   1071篇
  2006年   1036篇
  2005年   943篇
  2004年   813篇
  2003年   711篇
  2002年   633篇
  2001年   580篇
  2000年   575篇
  1999年   530篇
  1998年   335篇
  1997年   336篇
  1996年   418篇
  1995年   369篇
  1994年   297篇
  1993年   196篇
  1992年   400篇
  1991年   384篇
  1990年   284篇
  1989年   340篇
  1988年   273篇
  1987年   254篇
  1986年   255篇
  1985年   249篇
  1984年   234篇
  1983年   215篇
  1982年   131篇
  1981年   137篇
  1980年   141篇
  1979年   155篇
  1978年   145篇
  1977年   105篇
  1974年   104篇
  1973年   141篇
  1972年   136篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Childhood sarcoidosis is a rare disorder with protean manifestations. The case of a child with prolonged fever, hepatosplenomegaly, pancytopenia, and systemic necrotizing vasculitis manifesting as fever, rash and skin infarctions, digital pregangrene, and foot drop is reported. This is the first case of systemic necrotizing vasculitis reported in sarcoidosis. The fulminant course of the disease required treatment with intravenous pulsed cyclophosphamide and high doses of corticosteroids. The spectrum of vasculitis in childhood and adult sarcoidosis is reviewed.  相似文献   
102.
From mid-October 1989 to mid-July 1990 all newly admitted residents to Bury Local Authority Residential Homes were comprehensively medically screened. In a series of 100 residents eight had early Parkinson's disease (six of them hitherto undiagnosed). Seven showed evidence of Vitamin C deficiency. Of the seven showing evidence of deficiency, four suffered from early Parkinson's disease. Of the 93 without evidence of Vitamin C deficiency only four had Parkinson's disease. This indicates a significantly higher prevalence of Parkinson's disease in the group with Vitamin C deficiency (P less than 0.001 using Fisher's exact).  相似文献   
103.
Interleukin 1 (IL-1) and tumor necrosis factor alpha are thought to contribute to the inflammatory response associated with autoimmune diseases. Transforming growth factor beta 1 (TGF-beta 1) counteracts many effects of these cytokines and has various immunosuppressive properties. In the present study, it is shown that microgram amounts of TGF-beta 1, injected daily for 1-2 weeks, protect against collagen-induced arthritis (CIA) and relapsing experimental allergic encephalomyelitis (REAE), the animal models for rheumatoid arthritis and multiple sclerosis, respectively. When administered during induction of the disease, TGF-beta 1 prevents CIA but only delays the onset of REAE by 2-3 days. However, when administered during a remission. TGF-beta 1 prevents the occurrence of relapses in REAE. The results suggest that TGF-beta 1 has powerful anti-inflammatory effects, mimicking in some respects the beneficial effects of immunosuppressive drugs in these experimental models of autoimmune disease, but without discernable adverse effects.  相似文献   
104.
105.
106.
This is a report of a patient on treatment for duodenal tuberculosis, who developed obstructive jaundice due to a benign stricture of the terminal common bile duct. This complication of duodenal tuberculosis, to our knowledge, has not been reported before. Percutaneous, transhepatic balloon dilatation of the stricture alleviated the jaundice.  相似文献   
107.
Background. We developed a method of closed-chest cardiopulmonary bypass to arrest and protect the heart with cardioplegic solution. This method was used in 54 dogs and the results were retrospectively analyzed.

Methods. Bypass cannulas were placed in the right femoral vessels. A balloon occlusion catheter was passed via the left femoral artery and positioned in the ascending aorta. A pulmonary artery vent was placed via the jugular vein. In 17 of the dogs retrograde cardioplegia was provided with a percutaneous coronary sinus catheter.

Results. Cardiopulmonary bypass time was 111 ± 27 minutes (mean ± standard deviation) and cardiac arrest time was 66 ± 21 minutes. Preoperative cardiac outputs were 2.9 ± 0.70 L/min and postoperative outputs were 2.9 ± 0.65 L/min (p = not significant). Twenty-one-French and 23F femoral arterial cannulas that allowed coaxial placement of the ascending aortic balloon catheter were tested in 3 male calves. Line pressures were higher, but not clinically limiting, with the balloon catheter placed coaxially.

Conclusions. Adequate cardiopulmonary bypass and cardioplegia can be achieved in the dog without opening the chest, facilitating less invasive cardiac operations. A human clinical trial is in progress.  相似文献   

108.
109.
We present our experience with twenty children with insulin dependent diabetes mellitus admitted during the past 2 1/2 years. Sixteen patients were admited with acute onset of ketoacidosis while four were having gradual onset. Active and symptomatic treatment was started in all diabetic ketoacidotic patients. One patient died during the acute stage. Eleven patients were followed for 3–6 months or more. Glycosylated hemoglobin was considered as a criteria for control. Three had good control, two fair and six poor control; six developed diabetic ketoacidosis and three developed hypoglycemia  相似文献   
110.
M. J. Ball  BSc  MB  BCh  MRCP    J. W. Sear  BSc  PhD  FFARCS  DRCOG   《Anaesthesia》1986,41(4):423-426
Critically ill patients are usually in a catabolic state and may require total parenteral nutrition; this often includes lipid emulsions. Any adverse effects of constituents on pulmonary function, white cell function or the haemocoagulation system could have disastrous consequences in such patients. We have investigated the effects of a new intravenous lipid preparation containing medium chain triglycerides, which, in severely ill malnourished patients are theoretically a preferable energy source to conventional drug chain triglycerides. In a pilot study 17 critically ill patients whose lungs were artificially ventilated were given this lipid emulsion; no adverse effects were observed. Arterial oxygen and carbon dioxide tensions, ratio of inspired oxygen fractional concentration to arterial oxygen tension, platelet and white cell counts all remained constant and the complement system was not activated.  相似文献   
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