收费全文 | 9628篇 |
免费 | 842篇 |
国内免费 | 30篇 |
耳鼻咽喉 | 63篇 |
儿科学 | 363篇 |
妇产科学 | 289篇 |
基础医学 | 1280篇 |
口腔科学 | 70篇 |
临床医学 | 1349篇 |
内科学 | 1694篇 |
皮肤病学 | 149篇 |
神经病学 | 1117篇 |
特种医学 | 178篇 |
外科学 | 877篇 |
综合类 | 84篇 |
一般理论 | 15篇 |
预防医学 | 1635篇 |
眼科学 | 88篇 |
药学 | 727篇 |
中国医学 | 4篇 |
肿瘤学 | 518篇 |
2024年 | 24篇 |
2023年 | 146篇 |
2022年 | 173篇 |
2021年 | 335篇 |
2020年 | 257篇 |
2019年 | 385篇 |
2018年 | 395篇 |
2017年 | 334篇 |
2016年 | 367篇 |
2015年 | 321篇 |
2014年 | 429篇 |
2013年 | 599篇 |
2012年 | 833篇 |
2011年 | 863篇 |
2010年 | 442篇 |
2009年 | 336篇 |
2008年 | 605篇 |
2007年 | 629篇 |
2006年 | 541篇 |
2005年 | 476篇 |
2004年 | 451篇 |
2003年 | 394篇 |
2002年 | 371篇 |
2001年 | 76篇 |
2000年 | 51篇 |
1999年 | 63篇 |
1998年 | 64篇 |
1997年 | 44篇 |
1996年 | 54篇 |
1995年 | 38篇 |
1994年 | 33篇 |
1993年 | 38篇 |
1992年 | 39篇 |
1991年 | 35篇 |
1990年 | 40篇 |
1989年 | 28篇 |
1988年 | 26篇 |
1987年 | 17篇 |
1986年 | 22篇 |
1985年 | 19篇 |
1984年 | 20篇 |
1983年 | 10篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1978年 | 5篇 |
1977年 | 5篇 |
1975年 | 6篇 |
1974年 | 5篇 |
1972年 | 4篇 |
1941年 | 4篇 |
Objectives
The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors.Design
Pilot randomised-controlled trial.Methods
Seventeen female cancer survivors (mean: 62.9 ± 7.8 years) were randomised into three groups: high-intensity interval training (HIIT, n = 6); moderate-intensity continuous training (MOD, n = 5); or wait-list control (CON, n = 6). The HIIT and MOD groups exercised on a cycle ergometer 3 days/week for 12-weeks. Primary outcomes were cognitive function assessments utilising CogState. Secondary outcomes were resting middle cerebral artery blood flow velocity, cerebrovascular reactivity and aerobic fitness (VO2peak). Data were analysed with General Linear Mixed Models and Cohen’s d effect sizes were calculated.Results
All 17 participants who were randomised were available for follow-up analysis and adherence was similar for HIIT and MOD (78.7 ± 13.2% vs 79.4 ± 12.0%; p = 0.93). Although there were no significant differences in the cognitive and cerebrovascular outcomes, HIIT produced moderate to large positive effects in comparison to MOD and CON for outcomes including episodic memory, working memory, executive function, cerebral blood flow and cerebrovascular reactivity. HIIT significantly increased VO2peak by 19.3% (d = 1.28) and MOD had a non-significant 5.6% (d = 0.72) increase, compared to CON which had a 2.6% decrease.Conclusions
This study provides preliminary evidence that HIIT may be an effective exercise intervention to improve cognitive performance, cerebrovascular function and aerobic fitness in breast cancer survivors. Considering the sample size is small, these results should be confirmed through larger clinical trials. 相似文献![点击此处可从《Addiction (Abingdon, England)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Background
Self-report recall questionnaires are commonly used to measure physical activity, energy expenditure and time use in children and adolescents. However, self-report questionnaires show low to moderate validity, mainly due to inaccuracies in recalling activity in terms of duration and intensity. Aside from recall errors, inaccuracies in estimating energy expenditure from self-report questionnaires are compounded by a lack of data on the energy cost of everyday activities in children and adolescents. This article describes the development of the Multimedia Activity Recall for Children and Adolescents (MARCA), a computer-delivered use-of-time instrument designed to address both the limitations of self-report recall questionnaires in children, and the lack of energy cost data in children. 相似文献Methods: With approval, 300 consenting healthy patients, aged 18-50 yr, presenting for elective surgery requiring relaxant general anesthesia with a broad range of agents were studied. Patients were interviewed on emergence and 2-4 h postoperatively. The Bispectral Index was recorded from induction until the first interview. Dream content and form were also assessed.
Results: Dreaming was reported by 22% of patients on emergence. There was no difference between dreamers and nondreamers in median Bispectral Index values during maintenance (37 [23-55] vs. 38 [20-59]; P = 0.68) or the time at Bispectral Index values greater than 60 (0 [0-7] vs. 0 [0-31] min; P = 0.38). Dreamers tended to be younger and male, to have high home dream recall, to receive propofol maintenance or regional anesthesia, and to open their eyes sooner after surgery. Most dreams were similar to dreams of sleep and were pleasant, and the content was unrelated to surgery. 相似文献