全文获取类型
收费全文 | 37162篇 |
免费 | 6675篇 |
国内免费 | 153篇 |
专业分类
耳鼻咽喉 | 774篇 |
儿科学 | 1250篇 |
妇产科学 | 1089篇 |
基础医学 | 2233篇 |
口腔科学 | 2787篇 |
临床医学 | 6463篇 |
内科学 | 7976篇 |
皮肤病学 | 625篇 |
神经病学 | 3441篇 |
特种医学 | 1282篇 |
外科学 | 5322篇 |
综合类 | 247篇 |
现状与发展 | 12篇 |
一般理论 | 16篇 |
预防医学 | 4986篇 |
眼科学 | 712篇 |
药学 | 1090篇 |
中国医学 | 17篇 |
肿瘤学 | 3668篇 |
出版年
2024年 | 179篇 |
2023年 | 1215篇 |
2022年 | 584篇 |
2021年 | 1161篇 |
2020年 | 1532篇 |
2019年 | 984篇 |
2018年 | 1849篇 |
2017年 | 1656篇 |
2016年 | 1897篇 |
2015年 | 1972篇 |
2014年 | 2531篇 |
2013年 | 3238篇 |
2012年 | 1994篇 |
2011年 | 2088篇 |
2010年 | 2048篇 |
2009年 | 2526篇 |
2008年 | 1774篇 |
2007年 | 1571篇 |
2006年 | 1675篇 |
2005年 | 1391篇 |
2004年 | 1146篇 |
2003年 | 1091篇 |
2002年 | 934篇 |
2001年 | 501篇 |
2000年 | 362篇 |
1999年 | 489篇 |
1998年 | 637篇 |
1997年 | 582篇 |
1996年 | 600篇 |
1995年 | 464篇 |
1994年 | 370篇 |
1993年 | 318篇 |
1992年 | 241篇 |
1991年 | 209篇 |
1990年 | 192篇 |
1989年 | 197篇 |
1988年 | 175篇 |
1987年 | 171篇 |
1986年 | 146篇 |
1985年 | 134篇 |
1984年 | 120篇 |
1983年 | 129篇 |
1982年 | 121篇 |
1981年 | 109篇 |
1980年 | 90篇 |
1979年 | 77篇 |
1978年 | 65篇 |
1977年 | 64篇 |
1976年 | 58篇 |
1974年 | 50篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Kay Kathryn L Roberts Beverley J Turnbull 《The Australian journal of advanced nursing》2002,20(2):8-14
The aim of this study was to document the amount of recent change in Australian nurse academics' scholarly productivity and to investigate the influence of demographic factors such as gender, academic rank, qualifications, increase in qualifications, state of residence, university and university size. Scholarly productivity was calculated from an audit of journal articles. The findings of this study indicate that, while there has been a slight increase in scholarly productivity in the last five years, nursing still lags behind other disciplines. Scholarly productivity was found to be positively associated with highest academic qualification, academic rank and promotion. The study indicates the continuing need for senior nurse academics to provide mentoring to colleagues and foster the development of skills associated with scholarly productivity. 相似文献
32.
33.
Transcutaneous oxygen (TcPO(2)) measurements provide a noninvasive, objective determination of the oxygen level at the skin surface. This offers a means of estimating the underlying circulation and tissue oxygenation. The purpose of the pilot study was to measure the TcPO(2) value of the lower extremity of healthy men and women and of patients with peripheral arterial disease (PAD) in 4 different body and leg positions 24 hours after peripheral vascular surgery reconstruction. The specific aim was to determine if lower-extremity TcPO(2) measurements were affected by changes in extremity position in these subject populations. A convenience sample of 4 healthy health care professionals and 4 patients who had peripheral vascular reconstruction surgery 24 hours before the measurements were studied. Subjects were studied in 4 different leg and body positions: supine with legs extended, sitting with legs dependent, a 5 degrees head-up reverse Trendelenburg, and supine with legs elevated 10 in. The Radiometer TCM30 TcPO(2) monitor was used to carry out these measures. Findings revealed a statistically significant difference in TcPO(2) measurements between the 2 groups, with the healthy subjects having a significantly higher TcPO(2) measurement in all extremity positions compared with the revascularized subjects with PAD (P =.02-.05). Significant changes were noted in both the foot temperature (P =.03) and TcPO(2) measurements with extremity positions within the healthy subject group (P =.001). The foot and leg TcPO(2) measurements affect from leg and body position did not reach significance (P =.09) in the subjects with PAD. No change in foot temperature with extremity positioning (P =.42) was noted in the subjects with PAD. This pilot study provides a base in which additional research will be performed with TcPO(2) measurements in both the healthy and revascularized person. 相似文献
34.
The epidemiology of viral hepatitis in US Navy enlisted personnel was reviewed for the years 1975-1984. Hospital discharge summaries of all active duty enlisted personnel admitted to a US Navy treatment facility were used for the study. From 1975 to 1984, total first hospitalizations for viral hepatitis declined from 128 per 100,000 personnel (95% confidence interval (Cl) 118-139) to 56 per 100,000 personnel (95% Cl 50-63). The highest incidence of acute viral hepatitis (115 per 100,000 personnel) was found in the youngest age groups aged 24 years and less. Risk factors for acute hepatitis included a previous hospitalization with either drug abuse (relative risk = 363) or a sexually transmitted disease (relative risk = 25) listed among the discharge diagnoses. Having a medical job classification was also associated with an increased risk of acute hepatitis. The steep decline in the incidence of viral hepatitis during this 10-year period may have been due to decreasing drug abuse in the US Navy. Immunization of high-risk groups in the US Navy with hepatitis B vaccine could be an effective policy for the prevention of acute viral hepatitis. 相似文献
35.
Michael C. Dalsing MD Melissa Kevorkian BS Beth Raper BA Craig Nixon MS Stephen G. Lalka MD Dolores F. Cikrit MD Joseph L. Unthank PhD Malcolm B. Herring MD 《Annals of vascular surgery》1989,3(2):127-133
This study evaluates the potential for endothelial seeding of a collagen-impregnated Dacron graft with or without surface modifiers (fibronectin, heparin) to attach and retain these cells during flow. Human umbilical endothelial cells were harvested, cultured, labeled with Indium111-oxine and seeded onto 30 mm X 4 mm diameter grafts. Six graft surfaces were studied: 1) a collagen-impregnated Dacron graft, HemashieldR (C); 2) C + fibronectin (C + F); 3) C + heparin (C + H); 4) C + F + H; 5) HytrelR + F (Hyt + F); and 6) Hyt + F + H. Radioactive loss determined the percentage attachment and then percentage retention of labeled inoculum after a one-hour in vitro perfusion. Scanning electron and light microscopy demonstrated the endothelium on the graft surface following perfusion. Fibronectin-coated grafts had a significantly higher percentage attachment than those without fibronectin (ANOVA, P less than 0.05). However, the percentage retention following perfusion was similar for all Dacron grafts and statistically inferior to the HytrelR grafts studied (ANOVA, P less than 0.05). SEM evaluation of the C + F + H graft surface was qualitatively the most impressive Dacron surface for seeding, yet was inferior to the HytrelR graft. We conclude that fibronectin benefits the initial attachment of endothelium to collagen-coated Dacron rivaling the HytrelR surface. Fibronectin does not improve percentage retention of the HemashieldR surface during perfusion, therefore, some of its initial benefit is lost. 相似文献
36.
37.
This study evaluated health risks associated with U.S. Navy submarine duty by comparing hospitalization rates of submariners with surface ship personnel. The groups were compared using age-adjusted hospitalization rates for 16 major diagnostic categories and several specific diagnoses postulated to be submarine associated. Submarine personnel did not have significantly higher hospitalization rates for any diagnostic categories nor for any of the submarine-associated illnesses. Submariner relative risk of hospital admissions was greater for a few selected diagnoses but statistical significance was not attained. Submarine personnel had lower hospitalization rates for nearly all of the diagnostic categories examined. Reasons for these lower rates may be stringent screening of submariners, higher levels of education among submariners, difficulty of evacuation from a submarine, and the healthy-worker effect. The health status of U.S. Navy personnel does not seem to be adversely affected by submarine duty. 相似文献
38.
39.
40.