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   1601931篇
  免费   131518篇
  国内免费   2581篇
耳鼻咽喉   21647篇
儿科学   52930篇
妇产科学   46225篇
基础医学   227791篇
口腔科学   47210篇
临床医学   140916篇
内科学   314928篇
皮肤病学   34090篇
神经病学   130190篇
特种医学   64723篇
外国民族医学   474篇
外科学   243793篇
综合类   39715篇
现状与发展   3篇
一般理论   544篇
预防医学   122856篇
眼科学   36472篇
药学   121256篇
  3篇
中国医学   2974篇
肿瘤学   87290篇
  2018年   14770篇
  2016年   12903篇
  2015年   15032篇
  2014年   20653篇
  2013年   31360篇
  2012年   42563篇
  2011年   44769篇
  2010年   26343篇
  2009年   25315篇
  2008年   43007篇
  2007年   45262篇
  2006年   46073篇
  2005年   44693篇
  2004年   44110篇
  2003年   42195篇
  2002年   41303篇
  2001年   75695篇
  2000年   78340篇
  1999年   66391篇
  1998年   17734篇
  1997年   16337篇
  1996年   16315篇
  1995年   16021篇
  1994年   15071篇
  1993年   14217篇
  1992年   55428篇
  1991年   53780篇
  1990年   52566篇
  1989年   50834篇
  1988年   47221篇
  1987年   46564篇
  1986年   44287篇
  1985年   42844篇
  1984年   32036篇
  1983年   27568篇
  1982年   16145篇
  1981年   14437篇
  1980年   13565篇
  1979年   30460篇
  1978年   21064篇
  1977年   17764篇
  1976年   16694篇
  1975年   17577篇
  1974年   21486篇
  1973年   20673篇
  1972年   18855篇
  1971年   17771篇
  1970年   16289篇
  1969年   15268篇
  1968年   13949篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
As in many other scientific disciplines, in gerontology adaptation is a central term. Yet it is not being used in a standardized way. This article describes the concepts and theoretical approaches which can be identified in Social Gerontology, together with their functions and the results of research.  相似文献   
992.
993.
The case reported here demonstrates the importance of considering the possibility of occult malignancy in young patients presenting with extensive or migratory thromboses in atypical locations that appear resistant to standard therapy. Suspicion for malignancy-related thrombosis is heightened by the absence of known precipitating causes and by a negative family history of thrombosis. The search for the responsible underlying neoplasm can be frustrating, but diagnosis and successful treatment of the tumor remain the keys to controlling the abnormal thrombotic state.  相似文献   
994.
995.
996.
We report histological changes in four patients with port wine stains treated with 578 nm yellow light from a high power copper vapour laser. Histology showed that selective damage occurred to the ectatic blood-vessels in the dermis, without haemorrhage and damage to non-vascular structures, and without scarring. The initial damage to the overlying epidermis was not permanent, and the damaged ectatic vessels returned to normal size or were completely necrosed and replaced by collagen.  相似文献   
997.
The present status of total colectomy with ileorectal anastomosis in the surgical treatment of inflammatory bowel disease is examined. Special reference is made to the different indications for the use of the operation in Crohn's disease and in ulcerative colitis. The late results are illustrated by the outcome in the 59 patients in a personal series, and other published results.  相似文献   
998.
Synovectomy of the knee in patients with hemophilia presenting in countries with demographic characteristics that make central referral difficult is the subject of this article. Ten patients, six surgeons, and two countries contributed to this study, which demonstrated that approximately 40% of these patients had no further hemarthroses into the affected joint and the remainder had reduced frequency and severity of bleeding. Continuous passive motion has an important place in postoperative management, and manipulation with the patient under anesthesia is of doubtful value. The possible relationship between diminished range of movement and a successful outcome in terms of abolition of hemorrhage is explored. One patient underwent synovectomy of the knee without complication; the other nine suffered significant complications.  相似文献   
999.
Indirect evidence suggests that amphetamine (AMPH) releases dopamine (DA) from an extravesicular, cytoplasmic pool. Disruption of vesicular DA storage by reserpine has been hypothesized to increase the concentration of extravesicular DA available for release by AMPH, which is consistent with the observation that reserpine does not prevent but augments the behavioral response to AMPH. In order to more directly test this hypothesis, the in vivo microdialysis technique was used to concurrently examine the behavioral and striatal dopaminergic response to AMPH (1.25 or 2.5 mg/kg) 24 h following reserpine pretreatment (2.5 mg/kg). Reserpine decreased tissue levels of DA by approximately 90% and reduced baseline dialysate DA concentrations by approximately 80%. Reserpine augmented the behavioural effects of AMPH, particularly increasing the occurrence and intensity of stereotypies. In contrast, reserpine did not alter the amount or duration of AMPH-induced DA release. This observation confirms that DA release by AMPH does not depend on vesicular stores but is inconsistent with the hypothesis that augmentation or behaviour by reserpine results from increased striatal DA release.  相似文献   
1000.
The results of this controlled study of the treatment of 57 patients with Gilles de la Tourette's syndrome suggested that both haloperidol and pimozide were more effective than placebo, but that haloperidol was slightly more effective than pimozide. Adverse effects occurred more frequently with haloperidol vs placebo than with pimozide vs placebo, but the frequency was not significantly different for haloperidol compared with pimozide. Clinically significant cardiac effects did not occur at a maximum dosage of 0.3 mg/kg or 20 mg/d for pimozide and 10 mg/d for haloperidol. However, the QTc interval was prolonged during pimozide treatment compared with that during haloperidol treatment, although the values for both medications were not in an abnormal range.  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