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   515321篇
  免费   33437篇
  国内免费   623篇
耳鼻咽喉   6900篇
儿科学   16868篇
妇产科学   13540篇
基础医学   85186篇
口腔科学   14516篇
临床医学   44430篇
内科学   93918篇
皮肤病学   12177篇
神经病学   36237篇
特种医学   18497篇
外国民族医学   63篇
外科学   77243篇
综合类   8495篇
一般理论   118篇
预防医学   39059篇
眼科学   12204篇
药学   40617篇
中国医学   1008篇
肿瘤学   28305篇
  2018年   4957篇
  2015年   4542篇
  2014年   6130篇
  2013年   9617篇
  2012年   12952篇
  2011年   14351篇
  2010年   8362篇
  2009年   7826篇
  2008年   13788篇
  2007年   14795篇
  2006年   15001篇
  2005年   14425篇
  2004年   14097篇
  2003年   13450篇
  2002年   13302篇
  2001年   24092篇
  2000年   25107篇
  1999年   20587篇
  1998年   5439篇
  1997年   4713篇
  1996年   5053篇
  1995年   4628篇
  1994年   4321篇
  1993年   4139篇
  1992年   15734篇
  1991年   16316篇
  1990年   16427篇
  1989年   15803篇
  1988年   14584篇
  1987年   14426篇
  1986年   13611篇
  1985年   12985篇
  1984年   9634篇
  1983年   8254篇
  1982年   4565篇
  1981年   4231篇
  1979年   9420篇
  1978年   6858篇
  1977年   5773篇
  1976年   5605篇
  1975年   6396篇
  1974年   7638篇
  1973年   7133篇
  1972年   6961篇
  1971年   6687篇
  1970年   6173篇
  1969年   5890篇
  1968年   5562篇
  1967年   5013篇
  1966年   4452篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Eighty-nine cases of chronic bronchitis were matched against167 asymptomatic controls from the glass bangle industry ofFirozabad. Factors of age, social status, smoking habit andduration of exposure were studied. Duration of exposure wasfound to be a factor contributing significantly to the causationof disease. Requests for reprints should be addressed to: Dr B. N. Gupta, Division of Epidemilogy, Industrial Toxicology Research Centre, Mahatma Gandhi Marg, Lucknow P.O. Box 80, 226001, India  相似文献   
42.
43.
In order to satisfy the need to restore the aesthetics, phonetics and comfort and to facilitate optimal hygiene procedures, 20 edentulous patients were treated with a new concept of overdenture therapy on implants ad modum Brånemark. After 24±3.5 months the patients were re‐examined. They were asked to answer a questionnaire and use a Visual Analogue Scale (VAS) to give their opinion on the prosthetic treatment. The results indicate that an implant‐retained overdenture in the maxilla with this design can satisfy the patients needs in aesthetics, phonetics and comfort and can 1 facilitate oral hygiene measures.  相似文献   
44.
45.
46.
47.
A retrospective analysis of results of treatment of 104 patients with fractures of long tubular bones associated with injuries of peripheral nerves has shown complex therapy to be necessary. Main components of this treatment were biogenic stimulators, vitamin B12, spasmolytic and dehydration drugs in combination with electrophoresis with potassium iodide and thermal procedures. Rapid disturbance of conductivity of nerve trunks after trauma should be followed by revision of the given segment of the extremity in order to remove hematoma and make reposition of displaced fragments of the bone, which can provide recovery of the disturbed function of the nerve.  相似文献   
48.
On the basis of experience with the treatment of more than 1,500 patients with post-burn defects, deformities, and trophic ulcers, the authors distinguished types of affection in which the traditional methods are ineffective. These 133 patients were subjected to plasty with ++cutaneo-fascial grafts; the zones of donor areas from which the grafts are taken are determined. Plasty with ++cutaneo-fascial grafts is indicated in defects of the face, deformity of the neck, total adduction contracture of the arm, defect of the breast, and affections of the hand, leg, and foot. Concrete grafts and the site from which they are taken for restoration of certain regions of the body are suggested. ++Cutaneo-fascial grafts make it possible to restore the shape, function, and the skin of the involved region.  相似文献   
49.
50.
Regional effects of craniotomy on cerebral circulation and metabolism, such as regional cerebral blood flow (rCBF), regional cerebral oxygen consumption (rCMRO2), regional oxygen extraction fraction (rOEF), and regional cerebral blood volume (rCBV) were examined by a PET (positron emission tomography) study concerning surgery that was performed on unruptured aneurysm patients. Eight patients with intracranial un-ruptured aneurysms were studied pre- and post-operatively by the 15O labelled-gas steady-state method, using HEADTOME-III. All patients underwent aneurysmal surgery performed by the transsylvian approach. There was a significant increase in the mean OEF values taken from the whole-brains of 8 patients, but there was not a significant change in CBF, CMRO2 or CBV. The increase in OEF was caused by decrease of O2 content, which was caused by post-operative decrease in the Hb value. So, this OEF increase was not the direct effect of craniotomy. In 2 patients, the rCBF and rCMRO2, in the fronto-temporal region (where craniotomy was performed) increased post-operatively. This regional effect suggests transient reactive hyperemia following compressive ischemia during the operative procedure, and metabolic demands for recovery of brain function. In 2 other patients, who had relatively low rCBFs during the pre-operative study, rCBF and rCMRO2 in the bi-frontal region had decreased more at the post-operative study. This change appears to have been caused by removal of cerebrospinal fluid and depression of the frontal lobe. From this study, it becomes evident that the regional effect of craniotomy on cerebral circulation and metabolism is not so great, when adequate microsurgical techniques are used.  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