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   515983篇
  免费   33606篇
  国内免费   614篇
耳鼻咽喉   6901篇
儿科学   16891篇
妇产科学   13536篇
基础医学   85415篇
口腔科学   14555篇
临床医学   44523篇
内科学   94046篇
皮肤病学   12187篇
神经病学   36413篇
特种医学   18505篇
外国民族医学   63篇
外科学   77274篇
综合类   8515篇
一般理论   120篇
预防医学   39133篇
眼科学   12154篇
药学   40622篇
中国医学   1007篇
肿瘤学   28343篇
  2018年   4955篇
  2015年   4539篇
  2014年   6100篇
  2013年   9608篇
  2012年   12943篇
  2011年   14378篇
  2010年   8358篇
  2009年   7826篇
  2008年   13772篇
  2007年   14790篇
  2006年   15016篇
  2005年   14435篇
  2004年   14119篇
  2003年   13471篇
  2002年   13331篇
  2001年   24137篇
  2000年   25155篇
  1999年   20638篇
  1998年   5446篇
  1997年   4732篇
  1996年   5067篇
  1995年   4649篇
  1994年   4342篇
  1993年   4153篇
  1992年   15773篇
  1991年   16352篇
  1990年   16461篇
  1989年   15841篇
  1988年   14610篇
  1987年   14452篇
  1986年   13629篇
  1985年   13003篇
  1984年   9668篇
  1983年   8270篇
  1982年   4583篇
  1981年   4253篇
  1979年   9444篇
  1978年   6883篇
  1977年   5799篇
  1976年   5623篇
  1975年   6415篇
  1974年   7653篇
  1973年   7145篇
  1972年   6973篇
  1971年   6694篇
  1970年   6182篇
  1969年   5902篇
  1968年   5570篇
  1967年   5021篇
  1966年   4458篇
排序方式: 共有10000条查询结果,搜索用时 43 毫秒
41.
Most authors consider the principal advantage of FG anastomoses (compared to microsurgical anastomoses) to be shorter operating time, reduced surgical trauma to oviduct stumps, and absence of tissue ischemia. These features promote reparative regeneration and decrease adhesion formation, resulting in complete recanalization of fallopian tubes. To date, the majority of work on FG is confined to the experimental development of surgical techniques. Investigations in reconstructive gynecological surgery are quite uncommon. The physical properties of FG and the positive results of available experimental studies suggest that further development of surgical techniques using FG in obstetrics and gynecology is worthwhile.  相似文献   
42.
Background : The clinical course of chronic hepatitis B is variable. Patients with hepatic decompensation, bridging necrosis or an alpha-fetoprotein level greater than 100 ng/mL during an exacerbation of hepatitis have a high risk of developing cirrhosis. This study was conducted to evaluate the effect of colchicine in the prevention of cirrhosis in such patients.
Methods : Patients with risk factor(s) were randomized to receive either colchicine 5 mg/week or no specific treatment, the end point being development of cirrhosis.
Results : After a follow up period of 4 years, the treatment group had a marked reduction in exacerbations of acute hepatitis (32% vs. 63%/patient/year, P <0.005). Seven out of 38 patients in the treatment group and 10 out of 27 patients in the control group developed cirrhosis. The calculated cumulative incidence of cirrhosis by the end of first, second, third and fourth years in the treatment group was 8.7, 18.6, 32 and 32%, respectively. The corresponding figures in the control group were 30, 35.5, 46.3 and 73.2%, respectively, with a P -value of 0.057.
Conclusions : The results suggest that colchicine may prevent cirrhosis in chronic hepatitis B patients with risk factor(s), possibly by suppressing exacerbations of hepatitis through an anti-inflammatory effect.  相似文献   
43.
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   
44.
45.
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   
46.
47.
48.
49.
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   
50.
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   
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