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   1465912篇
  免费   98623篇
  国内免费   1672篇
耳鼻咽喉   17790篇
儿科学   48786篇
妇产科学   38841篇
基础医学   209427篇
口腔科学   36580篇
临床医学   134378篇
内科学   283060篇
皮肤病学   28750篇
神经病学   120910篇
特种医学   55892篇
外国民族医学   265篇
外科学   209684篇
综合类   28319篇
现状与发展   4篇
一般理论   648篇
预防医学   126826篇
眼科学   31359篇
药学   104137篇
  7篇
中国医学   2694篇
肿瘤学   87850篇
  2021年   10836篇
  2019年   11484篇
  2018年   35330篇
  2017年   27615篇
  2016年   30706篇
  2015年   15182篇
  2014年   20578篇
  2013年   30600篇
  2012年   47669篇
  2011年   63074篇
  2010年   42309篇
  2009年   34641篇
  2008年   58685篇
  2007年   63218篇
  2006年   43021篇
  2005年   43432篇
  2004年   42731篇
  2003年   41762篇
  2002年   38685篇
  2001年   56439篇
  2000年   57523篇
  1999年   48414篇
  1998年   13814篇
  1997年   12589篇
  1996年   12858篇
  1995年   12145篇
  1994年   11290篇
  1992年   38275篇
  1991年   37788篇
  1990年   36596篇
  1989年   35364篇
  1988年   32757篇
  1987年   32077篇
  1986年   30565篇
  1985年   28837篇
  1984年   21990篇
  1983年   19243篇
  1982年   11401篇
  1979年   20958篇
  1978年   15419篇
  1977年   12805篇
  1976年   11863篇
  1975年   12827篇
  1974年   15607篇
  1973年   15377篇
  1972年   14521篇
  1971年   13555篇
  1970年   12807篇
  1969年   12085篇
  1968年   11248篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
951.
The long term recovery of a series of 27 patients who had undergone rupture and repair of an aneurysm of the anterior communicating artery was assessed using a number of neuropsychological measures. Testing took place 12 to 84 months post surgery. On the basis of the results from tests of intellect, memory, and conceptual learning, three subgroups of patients were identified: those with persuasive cognitive defects, those with evidence of residual frontal lobe damage and those who showed no evidence of dysfunction. The occurrence of cerebral vasospasm was the most consistent predictor of long term cognitive deficit.  相似文献   
952.
An improved method for determining 89Sr and 90Sr in urine   总被引:1,自引:0,他引:1  
A method has been developed for the rapid isolation and quantitation of 89Sr and 90Sr in urine samples. The radiostrontium is concentrated from the bulk urine sample by coprecipitation with calcium phosphate. The precipitate is then wet ashed with nitric acid, and a solution of the resulting residue in 2 M HNO3-0.5 M Al(NO3)3 is passed through an extraction chromatographic column containing a supported crown ether that preferentially retains strontium. Sorbed strontium may then be eluted from the column with either dilute HNO3 or water and counted via liquid scintillation. A new counting scheme that permits quantitation of both 89Sr and 90Sr on the same day the separation is performed is described.  相似文献   
953.
Seven patients with cystic fibrosis aged 6 to 20 were enrolled for 30 months in a daily exercise program. After 12 months conventional chest physiotherapy was withdrawn. Patients with low initial Shwachman scores improved as regards maximal working capacity. Spirometric data and volume of trapped gas indicated opening of closed airways. We suggest that physical exercise in general should be the basis of pulmonary therapy in cystic fibrosis. Other forms of physiotherapy are advisable when hard physical exercise is not feasible.  相似文献   
954.
Thirteen patients with a malignant germ cell tumor of the ovary have been treated with a combination of vinblastine, bleomycin, and cisplatin (VBP). In 12 patients a complete remission was reached, which was maintained in 10 of these patients. One patient with large tumor residues and a partial remission became CR after surgery. The tumor recurred in 2 patients after 6 and 27 months. Overall, 11 of these patients are in long-term remission, from 14 to 84 months after the start of treatment. VBP is an effective treatment for malignant germ cell tumors of the ovary, even in patients with large tumor residuals.  相似文献   
955.
956.
957.
There is limited information regarding oral health status and other predictors of oral health‐related quality of life. An association between oral health status and perceived oral health‐related quality of life (OHQOL) might help clinicians motivate patients to prevent oral diseases and improve the outcome of some dental public health programs. This study evaluated the relationship between older persons' OHQOL and their functional dentition, caries, periodontal status, chronic diseases, and some demographic characteristics. A group of 733 low‐income elders (mean age 72.7 ISD=4.71, 55.6% women, 55.1% members of ethnic minority groups in the U.S. and Canada) enrolled in the TEETH clinical trial were interviewed and examined as part of their fifth annual visit for the trial. OHQOL was measured by the Geriatric Oral Health Assessment Index (GOHAI); oral health and occlusal status by clinical exams and the Eichner Index; and demographics via interviews. Elders who completed the four‐year assessment had an average of 21.5 teeth (SD=6.9). with 8.5 occluding pairs (SD=4.6), and 32% with occlusal contacts in all four occluding zones. Stepwise multiple regressions were conducted to predict total GOHAI and its subscores (Physical, Social, and Worry). Functional dentition was a less significant predictor than ethnicity and being foreign‐bom. These variables, together with gender, years since immigrating, number of carious roots, and periodontal status, could predict 32% of the variance in total GOHAI, 24% in Physical, 27% in Social, and 21 % in the Worry subscales. These findings suggest that functional dentition and caries influence older adults' OHQOL, but that ethnicity and immigrant status play a larger role.  相似文献   
958.
959.
960.
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