全文获取类型
收费全文 | 1734篇 |
免费 | 70篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 52篇 |
妇产科学 | 39篇 |
基础医学 | 114篇 |
口腔科学 | 59篇 |
临床医学 | 389篇 |
内科学 | 523篇 |
皮肤病学 | 51篇 |
神经病学 | 45篇 |
特种医学 | 10篇 |
外科学 | 153篇 |
综合类 | 37篇 |
一般理论 | 18篇 |
预防医学 | 120篇 |
眼科学 | 19篇 |
药学 | 143篇 |
中国医学 | 3篇 |
肿瘤学 | 22篇 |
出版年
2017年 | 18篇 |
2016年 | 21篇 |
2015年 | 26篇 |
2014年 | 32篇 |
2013年 | 44篇 |
2012年 | 10篇 |
2010年 | 51篇 |
2009年 | 60篇 |
2008年 | 12篇 |
2007年 | 12篇 |
2006年 | 17篇 |
2005年 | 11篇 |
2003年 | 12篇 |
2001年 | 24篇 |
2000年 | 14篇 |
1999年 | 43篇 |
1998年 | 60篇 |
1997年 | 91篇 |
1996年 | 94篇 |
1995年 | 59篇 |
1994年 | 58篇 |
1993年 | 64篇 |
1992年 | 51篇 |
1991年 | 55篇 |
1990年 | 49篇 |
1989年 | 56篇 |
1988年 | 53篇 |
1987年 | 41篇 |
1986年 | 32篇 |
1985年 | 28篇 |
1984年 | 41篇 |
1983年 | 38篇 |
1982年 | 26篇 |
1981年 | 33篇 |
1980年 | 23篇 |
1979年 | 16篇 |
1978年 | 16篇 |
1977年 | 18篇 |
1976年 | 13篇 |
1975年 | 11篇 |
1971年 | 20篇 |
1968年 | 11篇 |
1959年 | 20篇 |
1958年 | 37篇 |
1957年 | 32篇 |
1956年 | 44篇 |
1955年 | 33篇 |
1954年 | 28篇 |
1949年 | 11篇 |
1948年 | 12篇 |
排序方式: 共有1807条查询结果,搜索用时 15 毫秒
11.
12.
13.
PAUL J. GRUENEWALD 《Addiction (Abingdon, England)》2006,101(3):459-460
14.
15.
16.
17.
J. DAVID TALLEY M.D. FAYAZ SHAWL M.D. AUGUSTO PICHARD M.D. ALLESANDRO GIAMBARTOLOMEI M.D. PAUL OVERLIE M.D. ROBERT SIEGEL M.D. JOEL ROSENBERG M.D. CHRISTOPHER U. CATES M.D. FRANK CUMMINS M.D. EDWARD KOSINSKI M.D. 《Journal of interventional cardiology》1997,10(4):295-299
Lesions in the distal portion of coronary arteries are technological challenges with currently available percutaneous transluminal coronary angioplasty (PTCA) equipment. A study was performed at multiple centers to determine if new "fixed-wire" devices with a modified distal tip (a 2-cm flexible tip and 1-cm standard tip) would be useful in these situations. Three hundred twenty-three patients were included in the study, 75% male, mean age 63 ± 11 years. Four hundred ninety-three lesions were attempted; the overall success rate was 85%. Forty-six (14.2%) clinical complications occurred including: 5 deaths (1.1%); 2 nonfatal myocardial infarctions (0.6%); and 6 emergency coronary artery bypass grafting procedures (2.6%). A device malfunction was noted in 32 patients (9.9%), and included: 8 balloon ruptures or perforations (2.0%); 6 bent or damaged tips (1.9%); and 4 shaft/manifold leaks (1.2%). Two-month follow-up assessment for restenosis was done in 352 of 371 (95%) patients and at that time 89% were asymptomatic, had a negative functional test, or patent PTCA site by angiography. The new fixed-wire PTCA catheters with 1- and 2-cm flexible tips hold promise for dilating lesions in distal locations with an acceptable rate of complications. Additional investigation is needed to determine their role in the treatment of coronary artery disease with PTCA. 相似文献
18.
19.
Health status indicators for the population of Costa Rica comparedfavorably in the 1980s to those of more developed nations. Morbidityand mortality had been lowered, and health status differentialsbetween population subgroups had been narrowed. By 1984, mostof the objectives set by the World Health Organization had beenexceeded. These outcomes have been attributed to the successof a national primary health care program and to the role ofthe health assistant/asistente de salud in the operation ofthis program. This article examines the approach taken in achieving theseoutcomes. Of particular interest is the role of the health assistantas health educator in attaining the health promotion and diseaseprevention goals of the primary care program. Contemporary challenges which may diminish the role of the healthassistant and the possible consequences of this for public healthare considered, as is a recent government experiment which affordsa potential response to these issues. The latter, a new modelfor the organization and delivery of health services, featuresa partnership between government and a private sector providergroup. This arrangement retains the traditional role of thehealth assistant in primary care and enhances the health educationfunction of the health assistant. Under pressure and in transition, the health sector in CostaRica is striving to safeguard the admirable achievements ithas attained and to plan for further advances. It is clear thatunder present circumstances difficult choices must be made.One hopes that in the trade-offs made, those elements of theprimary health care program which have been essential to thisnation's success are not assigned a lower priority. 相似文献
20.
PETER T. BUSER M.D. MICHEL ZUBER M.D. PETER RICKENBACHER M.D. PAUL ERNE M.D. HANS-RUDOLF JENZER M.D. DIETER BURCKHARDT M.D. 《Echocardiography (Mount Kisco, N.Y.)》1997,14(6):597-605
To define the prevalence of cardioembolic sources found by transesophageal echocardiography (TEE) in different age groups of patients with and without cryptogenic systemic embolism, TEE risk factors for cardiogenic embolism were identified from 341 consecutive patients referred for TEE. One hundred and thirty-five had cryptogenic cerebral or systemic peripheral embolic events (CEE) and 206 other indications for TEE (CTR). Cardioembolic sources were found in 40% of CEE and in 29% of CTR (P < 0.02). Specifically, left atrial (LA) thrombi (P < 0.0001), atrial septal aneurysm with right-to-left shunt (P < 0.002), and atherosclerotic aortic plaques (P < 0.02) were more frequent. The prevalence of potential cardioembolic sources was significantly higher in patients ≥ 70-years old than in younger patients (P < 0.03), specifically LA thrombi (P < 0.004) and atherosclerotic aortic plaques (P < 0.0001). In patients ≥ 70-years old, potential cardioembolic sources were found in 63% and in 40% in CEE and CTR (P = 0.073), respectively. However, LA thrombi were more frequent in CEE (P < 0.003). Thus, potential cardioembolic sources observed by TEE are found more frequently in patients ≥ 70-years old than in younger patients. LA thrombi were more frequent in CEE than in CTR patients ≥ 70-years old. In patients ≥ 70-years old with CEE who are eligible for an anticoagulant regimen, a search for potential cardioembolic sources by TEE should be considered. 相似文献