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   519228篇
  免费   33606篇
  国内免费   648篇
耳鼻咽喉   6964篇
儿科学   16977篇
妇产科学   13678篇
基础医学   85689篇
口腔科学   14609篇
临床医学   44691篇
内科学   95007篇
皮肤病学   12255篇
神经病学   36680篇
特种医学   18591篇
外国民族医学   63篇
外科学   77921篇
综合类   8500篇
一般理论   118篇
预防医学   39270篇
眼科学   12215篇
药学   40762篇
中国医学   1021篇
肿瘤学   28471篇
  2018年   5141篇
  2016年   4202篇
  2015年   4637篇
  2014年   6275篇
  2013年   9826篇
  2012年   13294篇
  2011年   14765篇
  2010年   8547篇
  2009年   8004篇
  2008年   14032篇
  2007年   15039篇
  2006年   15267篇
  2005年   14661篇
  2004年   14286篇
  2003年   13620篇
  2002年   13457篇
  2001年   24095篇
  2000年   25106篇
  1999年   20591篇
  1998年   5466篇
  1997年   4733篇
  1996年   5056篇
  1995年   4644篇
  1994年   4331篇
  1992年   15738篇
  1991年   16320篇
  1990年   16428篇
  1989年   15802篇
  1988年   14578篇
  1987年   14422篇
  1986年   13603篇
  1985年   12975篇
  1984年   9631篇
  1983年   8252篇
  1982年   4560篇
  1981年   4237篇
  1979年   9419篇
  1978年   6857篇
  1977年   5774篇
  1976年   5603篇
  1975年   6397篇
  1974年   7636篇
  1973年   7131篇
  1972年   6960篇
  1971年   6685篇
  1970年   6172篇
  1969年   5888篇
  1968年   5559篇
  1967年   5013篇
  1966年   4450篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
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   
72.
73.
74.
75.
76.
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   
77.
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   
78.
The blood supply to the kidneys was studied in 106 children with urological diseases from angiograms. Computer analysis of 322 angiograms of patients with renal hypoplasia, dysplasia, hydronephrosis, megaureter, and abnormal mobility of the kidney was carried out. The results of angiography of a healthy kidney in 64 children were used to determine the normal parameters. The author gives a quantitative appraisal of the area of the kidney and its vessels, the calculation of the percentage of kidney vascularization, determination of the area of the renal cortex, the area of its vessels and percentage of vascularization, and the diameter of the large renal vessels. The study showed that the most informative parameters of the angiograms are as follows: the area of the renal vessels and its cortex, the percentage of vascularization of the Kidney and its cortex. Renal hypoplasia, dysplasia, megaureter, and hydronephrosis are characterized by different variants of disturbed blood supply of various severity.  相似文献   
79.
80.
Assessment of glomerular filtration rate (GFR) with inulin is cumbersome and time-consuming. Radioisotopic filtration markers have been studied as filtration markers because they can be used without continuous intravenous (IV) infusion and because analysis is relatively simple. Although the clearances of 99mTc-diethylenetriamine-pentaacetic acid (DTPA), 169Yb-DTPA, and 125I-iothalamate have each been compared with inulin, rarely has the comparability of radioisotopic filtration markers been directly evaluated in the same subject. To this purpose, we determined the renal clearance of inulin administered by continuous infusion and the above radioisotopic filtration markers administered as bolus injections, simultaneously in four subjects with normal renal function and 16 subjects with renal insufficiency. Subjects were studied twice in order to assess within-study and between-study variability. Unlabeled iothalamate was infused during the second half of each study to assess its effect on clearances. We found that renal clearance of 125I-iothalamate and 169Yb-DTPA significantly exceeded clearance of inulin in patients with renal insufficiency, but only by several mL.min-1.1.73m-2. Overestimation of inulin clearance by radioisotopic filtration markers was found in all normal subjects. No differences between markers were found in the coefficient of variation of clearances either between periods on a given study day (within-day variability) or between the two study days (between-day variability). The true test variability between days did not correlate with within-test variability. We conclude that the renal clearance of 99mTc-DTPA, 169Yb-DTPA, or 125I-iothalamate administered as a single IV or subcutaneous injection can be used to accurately measure GFR in subjects with renal insufficiency; use of the single injection technique may overestimate GFR in normal subjects.  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