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   22821篇
  免费   1613篇
  国内免费   89篇
耳鼻咽喉   155篇
儿科学   772篇
妇产科学   525篇
基础医学   3309篇
口腔科学   334篇
临床医学   2785篇
内科学   5004篇
皮肤病学   482篇
神经病学   2396篇
特种医学   388篇
外科学   2021篇
综合类   130篇
一般理论   28篇
预防医学   2529篇
眼科学   246篇
药学   1533篇
中国医学   43篇
肿瘤学   1843篇
  2024年   20篇
  2023年   215篇
  2022年   387篇
  2021年   768篇
  2020年   511篇
  2019年   760篇
  2018年   785篇
  2017年   577篇
  2016年   652篇
  2015年   714篇
  2014年   910篇
  2013年   1189篇
  2012年   1940篇
  2011年   1946篇
  2010年   1040篇
  2009年   875篇
  2008年   1516篇
  2007年   1568篇
  2006年   1543篇
  2005年   1430篇
  2004年   1317篇
  2003年   1162篇
  2002年   1019篇
  2001年   138篇
  2000年   90篇
  1999年   151篇
  1998年   192篇
  1997年   136篇
  1996年   133篇
  1995年   121篇
  1994年   82篇
  1993年   86篇
  1992年   43篇
  1991年   43篇
  1990年   41篇
  1989年   49篇
  1988年   34篇
  1987年   27篇
  1986年   33篇
  1985年   26篇
  1984年   39篇
  1983年   26篇
  1982年   24篇
  1981年   25篇
  1980年   19篇
  1979年   12篇
  1978年   14篇
  1976年   16篇
  1973年   13篇
  1971年   10篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
Introduction: Current research suggests that pediatric stroke is associated with a reduction in intellectual functioning. However, less is known about academic achievement and the contribution of specific executive functions to math and literacy in this population. The current study investigates behavioral ratings of executive functioning and their relationship to math and spelling performance in children with a history of unilateral arterial ischemic stroke.

Method: Thirty-two pediatric patients with stroke (Mage = 9.5 ± 2.7 years) and 32 demographically equivalent, healthy controls were tested on standardized measures of arithmetic, spelling, and intelligence. Executive functioning data were collected via standardized parent questionnaire.

Results: Relative to controls, stroke participants demonstrated significantly poorer functioning in math, spelling, metacognition, and behavioral-regulation. Pencil and paper arithmetic was particularly challenging for the stroke group, with 40% of patients reaching levels of clinical impairment. Hierarchical regression in stroke participants further revealed that metacognition was a robust predictor of academic deficits. Stroke occurring in later childhood and affecting cortical and subcortical brain regions also presented as potential clinical risk factors.

Conclusions: Children with stroke were especially vulnerable to math achievement deficits. Metacognition made a substantial contribution to academic achievement abilities among stroke patients, and results underscore the importance of early metacognitive skills in the completion of schoolwork. Results also emphasize that pediatric stroke patients are a heterogeneous group with regard to functioning and that there is value in examining standard score distributions of clinical participant samples.  相似文献   

5.
6.
7.
BACKGROUND: Stressful conditions lead to formation of excessive free radicals, and lipid peroxidation is one of the major outcomes of free radical-mediated injury that directly damages membranes and generates a number of secondary products. OBJECTIVES: To determine the levels of malondialdehyde, an end product of lipid peroxidation, according to demographic and occupational variables in workers of a prehospital emergency service and to analyse the relationship between malondialdehyde levels and burnout. MATERIAL AND METHODS: One hundred and eleven healthy workers of a prehospital emergency service and eighty aged-matched healthy individuals of both sexes as a control group were surveyed. Malondialdehyde levels were measured by the Bull and Marnett method. To measure burnout, the Maslach Burnout Inventory was used. RESULTS: Professional category is associated with lipid peroxidation and burnout levels (Malondialdehyde levels were: physicians 338.10+/-14.47, nurses 329.17+/-12.62 and technicians 296.74+/-14.28; burnout levels were: physicians 41.29+/-3.59, nurses 37.38+/-6.05 and technicians 35.33+/-5.87). Working at night and in the evening increased malondialdehyde and burnout levels. Malondialdehyde levels increase with age. No significant variations with respect to sex were detected. Significant variations in malondialdehyde levels were detected between singles (303.13+/-12.74) and married people (344.43+/-13.43) but not with respect to divorcees (326.44+/-11.74). Significant differences were detected in erythrocyte malondialdehyde levels between smokers (341.37+/-17.09) and nonsmokers (302.21+/-12.38), but not for alcohol consumption. CONCLUSIONS: These findings suggest a positive correlation between malondialdehyde, a biomarker of lipid peroxidation and occupational stress, as estimated by elements of the Maslach Burnout Inventory, and oxidative stress.  相似文献   
8.
9.
Successful efforts in improving breastfeeding initiation rates at an urban teaching hospital prompted the hospital to create a lactation consultant (LC) position in the outpatient setting to focus on breastfeeding duration. This article reviews the complexity of the clinic setting, with the challenges and benefits of the consultant's first year in one of the hospital's outpatient clinics. Preliminary data collected by the consultant suggest that patients counseled by the LC in the outpatient clinic setting have longer breastfeeding duration rates.  相似文献   
10.
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