全文获取类型
收费全文 | 987篇 |
免费 | 45篇 |
国内免费 | 23篇 |
学科分类
医药卫生 | 1055篇 |
出版年
2021年 | 12篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 5篇 |
2015年 | 10篇 |
2014年 | 5篇 |
2013年 | 11篇 |
2012年 | 16篇 |
2011年 | 14篇 |
2010年 | 13篇 |
2009年 | 27篇 |
2008年 | 16篇 |
2007年 | 38篇 |
2006年 | 28篇 |
2005年 | 35篇 |
2004年 | 19篇 |
2003年 | 13篇 |
2002年 | 19篇 |
2001年 | 10篇 |
2000年 | 18篇 |
1999年 | 24篇 |
1998年 | 54篇 |
1997年 | 43篇 |
1996年 | 57篇 |
1995年 | 46篇 |
1994年 | 33篇 |
1993年 | 39篇 |
1992年 | 10篇 |
1991年 | 14篇 |
1990年 | 14篇 |
1989年 | 36篇 |
1988年 | 37篇 |
1987年 | 35篇 |
1986年 | 31篇 |
1985年 | 44篇 |
1984年 | 25篇 |
1983年 | 24篇 |
1982年 | 28篇 |
1981年 | 26篇 |
1980年 | 14篇 |
1979年 | 8篇 |
1978年 | 9篇 |
1977年 | 26篇 |
1976年 | 21篇 |
1975年 | 18篇 |
1972年 | 2篇 |
1971年 | 3篇 |
1969年 | 4篇 |
1967年 | 2篇 |
1940年 | 1篇 |
排序方式: 共有1055条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
5.
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
6.
7.
8.
D L Greenman R L Kodell B Highman G J Schieferstein M J Norvell 《Food and chemical toxicology》1987,25(3):229-232
C3H/HeN-MTV+ female mice were fed diets containing 320 or 640 ppb diethylstilboestrol (DES). DES feeding was started at 3 wk of age and was either continued throughout life or discontinued after 4, 8 or 26 wk of administration. A control group consisted of mice fed the same diet without DES, for the duration of the experiment. Mice were killed when palpable body masses (presumed to be mammary adenocarcinomas) reached a diameter of 1 cm. Adenocarcinomas developed in 79% of control mice and 96% of the mice exposed to DES for 26 wk, irrespective of the dose. The frequency and rate of removal of tumour-bearing mice were not increased further with lifetime exposure at a given dose. The time at which the first tumour occurred was largely dependent on the duration of exposure, not dose. The rate of occurrence of subsequent tumours was dependent on dose and duration of exposure; the rate of removal of mice with mammary adenocarcinomas was significantly greater at 640 ppb than at 320 ppb DES. Tumour frequency was 83% in mice exposed to 320 ppb DES for 8 wk and in those exposed for 4 wk; however, tumours developed at a faster rate in mice exposed for 8 wk. Tumour frequency was 94-96% in mice exposed to 640 ppb DES for 4 wk and 8 wk, and tumours developed more rapidly in mice exposed for 8 wk than in those exposed for 4 wk. When data were plotted as log-dose v. log-t50 (time to a probability that half the mice would be removed with mammary tumours) linear extrapolation to the control log-t50 gave an estimate of the no-effect level of exposure to DES. This estimate was remarkably consistent for all data sets (40-93 ppb) and was independent of the duration of exposure. 相似文献
9.