全文获取类型
收费全文 | 1298篇 |
免费 | 66篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 4篇 |
儿科学 | 60篇 |
妇产科学 | 106篇 |
基础医学 | 142篇 |
口腔科学 | 19篇 |
临床医学 | 112篇 |
内科学 | 247篇 |
皮肤病学 | 8篇 |
神经病学 | 55篇 |
特种医学 | 315篇 |
外科学 | 79篇 |
综合类 | 38篇 |
预防医学 | 76篇 |
眼科学 | 6篇 |
药学 | 59篇 |
中国医学 | 1篇 |
肿瘤学 | 62篇 |
出版年
2023年 | 5篇 |
2021年 | 15篇 |
2019年 | 5篇 |
2018年 | 10篇 |
2016年 | 5篇 |
2015年 | 12篇 |
2014年 | 14篇 |
2013年 | 24篇 |
2012年 | 36篇 |
2011年 | 29篇 |
2010年 | 24篇 |
2009年 | 25篇 |
2008年 | 26篇 |
2007年 | 36篇 |
2006年 | 36篇 |
2005年 | 29篇 |
2004年 | 22篇 |
2003年 | 39篇 |
2002年 | 23篇 |
2001年 | 35篇 |
2000年 | 35篇 |
1999年 | 39篇 |
1998年 | 60篇 |
1997年 | 46篇 |
1996年 | 62篇 |
1995年 | 50篇 |
1994年 | 38篇 |
1993年 | 39篇 |
1992年 | 22篇 |
1991年 | 18篇 |
1990年 | 22篇 |
1989年 | 41篇 |
1988年 | 46篇 |
1987年 | 42篇 |
1986年 | 33篇 |
1985年 | 50篇 |
1984年 | 36篇 |
1983年 | 28篇 |
1982年 | 28篇 |
1981年 | 25篇 |
1980年 | 18篇 |
1979年 | 7篇 |
1978年 | 15篇 |
1977年 | 33篇 |
1976年 | 23篇 |
1975年 | 17篇 |
1973年 | 8篇 |
1971年 | 7篇 |
1969年 | 7篇 |
1968年 | 4篇 |
排序方式: 共有1389条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Enhanced endothelialization of expanded polytetrafluoroethylene grafts by fibroblast growth factor type 1 pretreatment. 总被引:4,自引:0,他引:4
H P Greisler D J Cziperle D U Kim J D Garfield D Petsikas P M Murchan E O Applegren W Drohan W H Burgess 《Surgery》1992,112(2):244-54; discussion 254-5
BACKGROUND. Biomaterial pretreatment with endothelial cell mitogens may enhance endothelialization. METHODS. Modified fibrin glue (FG) containing 1 ng/cm2 recombinant 125I-labeled fibroblast growth factor type 1 (125I-FGF-1), 20 micrograms/cm2 heparin, 2.86 mg/cm2 fibrinogen, and 2.86 x 10(-2) units/cm2 thrombin was pressure perfused into expanded polytetrafluoroethylene (ePTFE) grafts. Grafts were interposed into infrarenal aortas of 24 New Zealand white rabbits and explanted after 0, 5, 30, and 60 minutes and 1, 7, 14, and 30 days. Residual radioactivity was determined by gamma-counting. Remaining 125I-FGF-1 is expressed as percent of value at time 0. To determine the effect of the FG/FGF-1 on graft healing, three groups of 50 x 4 mm 60 microns internodal-distance nonreinforced ePTFE grafts were implanted in the aortoiliac position of 12 dogs. Group I (n = 12) contained the complete modified FG, group II (n = 6) contained FG with heparin but no FGF-1, and group III (n = 6) contained untreated identical ePTFE. Tritiated thymidine (0.5 microCi/kg) was injected intramuscularly 10 hours before explantation after 7 and 28 days for light and electron microscopy and en face autoradiography. RESULTS. Retention of 125I-FGF-1 showed rapid initial loss (delta %/delta min = -24.1) followed by slow loss after 1 hour (delta %/delta min = -0.03), with 13.4% +/- 6.9% remaining at 1 week and 3.8% +/- 1.1% at 30 days. Every FG/FGF-1 graft at 28 days showed extensive capillary ingrowth and confluent endothelialized luminal surfaces, not seen in any specimen of the other two groups. Autoradiography revealed a significant increase (p less than 0.05) in 3H-thymidine incorporation in the FG/FGF-1 grafts at 28 days versus all groups as a function of time and graft treatment. CONCLUSIONS. Pressure perfusion of an FGF-1/FG suspension into 60 microns internodal-distance ePTFE grafts promotes endothelialization through capillary ingrowth and increased endothelial cell proliferation. 相似文献
6.
Embargoes and sanctions are tools of foreign policy. They can induce a decline in economic activity in addition to reducing imports and untoward health effects can supervene, especially among older persons and those with chronic illnesses. Often, violations of the rights of life, health, social services, and protection of human dignity occur among innocent civilians in embargoed nations. This paper examines the effects of embargoes and sanctions against several nations, and calls for studies to determine ways in which economic warfare might be guided by the rule of humanitarian international law, to reduce the effects on civilians. It suggests that the ability to trade in exempted goods and services should be improved, perhaps by establishing uniform criteria and definitions for exemptions, operational criteria under which sanctions committees might function, and methods for monitoring the impact of sanctions on civilian populations in targeted states, particularly with regard to water purity, food availability, and infectious-disease control. Prospective studies are advocated, to generate the data needed to provide better information and monitoring capacity than presently exists. 相似文献
7.
8.
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
9.
10.