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   99528篇
  免费   29262篇
  国内免费   1121篇
耳鼻咽喉   2412篇
儿科学   2685篇
妇产科学   2364篇
基础医学   2535篇
口腔科学   5122篇
临床医学   25884篇
内科学   25219篇
皮肤病学   3328篇
神经病学   12124篇
特种医学   3832篇
外科学   18387篇
综合类   113篇
现状与发展   40篇
预防医学   13206篇
眼科学   2109篇
药学   1115篇
中国医学   13篇
肿瘤学   9423篇
  2024年   745篇
  2023年   5077篇
  2022年   1174篇
  2021年   2850篇
  2020年   5386篇
  2019年   2109篇
  2018年   6999篇
  2017年   7384篇
  2016年   7978篇
  2015年   8066篇
  2014年   10511篇
  2013年   12213篇
  2012年   3864篇
  2011年   3619篇
  2010年   6858篇
  2009年   9142篇
  2008年   3540篇
  2007年   2459篇
  2006年   3614篇
  2005年   2237篇
  2004年   1580篇
  2003年   1241篇
  2002年   1128篇
  2001年   1815篇
  2000年   1138篇
  1999年   1684篇
  1998年   2092篇
  1997年   1919篇
  1996年   1961篇
  1995年   1699篇
  1994年   1090篇
  1993年   918篇
  1992年   742篇
  1991年   634篇
  1990年   510篇
  1989年   521篇
  1988年   502篇
  1987年   376篇
  1986年   359篇
  1985年   293篇
  1984年   252篇
  1983年   295篇
  1982年   224篇
  1981年   196篇
  1980年   122篇
  1978年   122篇
  1977年   119篇
  1976年   84篇
  1974年   71篇
  1972年   70篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
PROBLEM: To compare depressive symptoms in children with attention deficit hyperactivity disorder (ADHD) to those in healthy children, and to explore the influence of individual and family factors on level of depression. METHODS: Individual interviews with 68 children, ages 7 to 12 years, in order to complete the Children's Depression Inventory. FINDINGS: Children with ADHD reported significantly more depressive symptoms than did children without ADHD; 14.7% of children with ADHD reached the threshold of a 19 point score, which suggests clinical depression. No significant effects of individual and family factors on level of depression were found. CONCLUSIONS: Children with ADHD are more inclined to experience depressive symptoms than are healthy children. To plan appropriate interventions, nurses evaluating and working with children with ADHD should always consider a possible coexistence of depressive symptoms.  相似文献   
122.
123.
124.
Immediate chairside replacement of an extracted anterior tooth may contribute to a patient's comfort, treatment acceptance, and expectations of treatment; however, fabrication of a custom restoration in the anterior region of the mouth may result in an esthetic compromise for patients during the fabrication period. Chairside tooth replacement is an excellent application of fiber-reinforced composite resin technology. This article presents an innovative, affordable chairside procedure in which Ribbond Multi-Purpose Bondable Reinforcement Ribbon is used to replace a single extracted anterior tooth using the patient's own tooth.  相似文献   
125.
126.
127.
128.
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   
129.
130.
The present study investigated the hypothesis that Staphylococcus aureus enterotoxin B (SEE) produces epithelial cell death and releases inflammatory cytokines that produce stromal infiltration during contact lens induced peripheral ulceration. Epithelial cells were incubated with different doses of SEB for various time periods. Culture supernatants were assayed for cytokines IL- lo, IL-6 and chemotactic agents IL-8 and LTB,. SEE induced the production of IL- I p and IL-8. Epithelial cells exposed for longer periods (48 h) with low concentrations of SEB produced significantly higher levels (N0.02) of IL-Ip and IL-8 (P<0.05) compared t o a 24 h exposure. SEB did not induce the production o f IL-6 and  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