全文获取类型
收费全文 | 944篇 |
免费 | 37篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 39篇 |
妇产科学 | 10篇 |
基础医学 | 114篇 |
口腔科学 | 12篇 |
临床医学 | 80篇 |
内科学 | 218篇 |
皮肤病学 | 7篇 |
神经病学 | 10篇 |
特种医学 | 313篇 |
外科学 | 61篇 |
综合类 | 12篇 |
预防医学 | 72篇 |
眼科学 | 6篇 |
药学 | 33篇 |
中国医学 | 1篇 |
肿瘤学 | 13篇 |
出版年
2021年 | 16篇 |
2020年 | 7篇 |
2019年 | 3篇 |
2018年 | 12篇 |
2017年 | 7篇 |
2016年 | 6篇 |
2015年 | 10篇 |
2014年 | 10篇 |
2013年 | 17篇 |
2012年 | 17篇 |
2011年 | 28篇 |
2010年 | 19篇 |
2009年 | 20篇 |
2008年 | 27篇 |
2007年 | 30篇 |
2006年 | 18篇 |
2005年 | 16篇 |
2004年 | 18篇 |
2003年 | 9篇 |
2002年 | 14篇 |
2001年 | 11篇 |
2000年 | 8篇 |
1999年 | 15篇 |
1998年 | 48篇 |
1997年 | 41篇 |
1996年 | 58篇 |
1995年 | 43篇 |
1994年 | 33篇 |
1993年 | 38篇 |
1992年 | 9篇 |
1991年 | 10篇 |
1990年 | 11篇 |
1989年 | 32篇 |
1988年 | 36篇 |
1987年 | 30篇 |
1986年 | 26篇 |
1985年 | 40篇 |
1984年 | 20篇 |
1983年 | 22篇 |
1982年 | 27篇 |
1981年 | 24篇 |
1980年 | 13篇 |
1979年 | 6篇 |
1978年 | 7篇 |
1977年 | 31篇 |
1976年 | 20篇 |
1975年 | 16篇 |
1973年 | 3篇 |
1972年 | 4篇 |
1965年 | 4篇 |
排序方式: 共有1003条查询结果,搜索用时 0 毫秒
1.
2.
3.
A randomized controlled trial of electromagnetic therapy in the primary care management of venous leg ulceration 总被引:1,自引:1,他引:0
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care. 相似文献
4.
5.
Sanjana VM; Johnston PA; Robertson CR; Jamison RL 《The American journal of physiology》1976,231(2):313-318
6.
7.
8.
9.
10.
Somatic mitochondrial DNA mutations in cortex and substantia nigra in aging and Parkinson's disease 总被引:5,自引:0,他引:5
Simon DK Lin MT Zheng L Liu GJ Ahn CH Kim LM Mauck WM Twu F Beal MF Johns DR 《Neurobiology of aging》2004,25(1):71-81
Oxidative damage to mitochondrial DNA (mtDNA) increases with age in the brain and can induce G:C to T:A and T:A to G:C point mutations. Though rare at any particular site, multiple somatic mtDNA mutations induced by oxidative damage or by other mechanisms may accumulate with age in the brain and thus could play a role in aging and neurodegenerative diseases. However, no prior study has quantified the total burden of mtDNA point mutation subtypes in the brain. Using a highly sensitive cloning and sequencing strategy, we find that the aggregate levels of G:C to T:A and T:A to G:C transversions and of all point mutations increase with age in the frontal cortex (FCtx). In the substantia nigra (SN), the aggregate levels of point mutations in young controls are similar to the levels in the SN or FCtx of elderly subjects. Extrapolation from our data suggests an average of 2.7 (FCtx) to 3.2 (SN) somatic point mutations per mitochondrial genome in elderly subjects. There were no significant differences between Parkinson's disease (PD) patients and age-matched controls in somatic mutation levels. These results indicate that individually rare mtDNA point mutations reach a high aggregate burden in FCtx and SN of elderly subjects. 相似文献