收费全文 | 59514篇 |
免费 | 5141篇 |
国内免费 | 2159篇 |
耳鼻咽喉 | 643篇 |
儿科学 | 688篇 |
妇产科学 | 1178篇 |
基础医学 | 9079篇 |
口腔科学 | 1571篇 |
临床医学 | 5458篇 |
内科学 | 11201篇 |
皮肤病学 | 1059篇 |
神经病学 | 4225篇 |
特种医学 | 2017篇 |
外国民族医学 | 11篇 |
外科学 | 7956篇 |
综合类 | 5096篇 |
现状与发展 | 1篇 |
一般理论 | 5篇 |
预防医学 | 3397篇 |
眼科学 | 1574篇 |
药学 | 5446篇 |
10篇 | |
中国医学 | 1209篇 |
肿瘤学 | 4990篇 |
2023年 | 316篇 |
2022年 | 713篇 |
2021年 | 1011篇 |
2020年 | 675篇 |
2019年 | 957篇 |
2018年 | 1462篇 |
2017年 | 1152篇 |
2016年 | 1087篇 |
2015年 | 1291篇 |
2014年 | 1703篇 |
2013年 | 1922篇 |
2012年 | 2704篇 |
2011年 | 2739篇 |
2010年 | 1589篇 |
2009年 | 1548篇 |
2008年 | 2265篇 |
2007年 | 2345篇 |
2006年 | 2193篇 |
2005年 | 1853篇 |
2004年 | 1587篇 |
2003年 | 1498篇 |
2002年 | 1409篇 |
2001年 | 4754篇 |
2000年 | 4661篇 |
1999年 | 4059篇 |
1998年 | 1469篇 |
1997年 | 1114篇 |
1996年 | 687篇 |
1995年 | 574篇 |
1994年 | 526篇 |
1993年 | 452篇 |
1992年 | 1975篇 |
1991年 | 1707篇 |
1990年 | 1552篇 |
1989年 | 1508篇 |
1988年 | 1324篇 |
1987年 | 1208篇 |
1986年 | 1071篇 |
1985年 | 912篇 |
1984年 | 592篇 |
1983年 | 467篇 |
1982年 | 250篇 |
1981年 | 182篇 |
1980年 | 142篇 |
1979年 | 282篇 |
1978年 | 77篇 |
1974年 | 75篇 |
1973年 | 95篇 |
1972年 | 72篇 |
1969年 | 66篇 |
![点击此处可从《Transfusion medicine (Oxford, England)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Objectives
Short successive periods of skeletal muscle disuse have been suggested to substantially contribute to the observed loss of skeletal muscle mass over the life span. Hospitalization of older individuals due to acute illness, injury, or major surgery generally results in a mean hospital stay of 5 to 7 days, during which the level of physical activity is strongly reduced. We hypothesized that hospitalization following elective total hip arthroplasty is accompanied by substantial leg muscle atrophy in older men and women.Design and participants
Twenty-six older patients (75 ± 1 years) undergoing elective total hip arthroplasty participated in this observational study.Measurements
On hospital admission and on the day of discharge, computed tomographic (CT) scans were performed to assess muscle cross-sectional area (CSA) of both legs. During surgery and on the day of hospital discharge, a skeletal muscle biopsy was taken from the m. vastus lateralis of the operated leg to assess muscle fiber type–specific CSA.Results
An average of 5.6 ± 0.3 days of hospitalization resulted in a significant decline in quadriceps (?3.4% ± 1.0%) and thigh muscle CSA (?4.2% ± 1.1%) in the nonoperated leg (P < .05). Edema resulted in a 10.3% ± 1.7% increase in leg CSA in the operated leg (P < .05). At hospital admission, muscle fiber CSA was smaller in the type II vs type I fibers (3326 ± 253 μm2 vs 4075 ± 279 μm2, respectively; P < .05). During hospitalization, type I and II muscle fiber CSA tended to increase, likely due to edema in the operated leg (P = .10).Conclusions
Six days of hospitalization following elective total hip arthroplasty leads to substantial leg muscle atrophy in older patients. Effective intervention strategies are warranted to prevent the loss of muscle mass induced by short periods of muscle disuse during hospitalization. 相似文献Research design and methods: A sample of 1139 reports received by the Shaanxi ADR Monitoring Center from January 2015 to December 2017 was selected. ADR report quality was evaluated using an ADR report quality evaluation system.
Results: None of the reports were rated as excellent and 1.40% (n = 16) as good. Report quality was better for new and serious reports than for general reports. Medical institutions generated higher quality reports than pharmaceutical manufacturers. Nurses generated higher quality reports than doctors, pharmacists, and other professionals. Reporters of different occupations showed significant differences in the quality of the indicators Reporting time limit, Intervention ADR time, ADR termination time, ADR intervention measures, Original disease, and Cause of medication (P = 0.000).
Conclusions: The ADR data quality was poor in western China, and of lower quality than reported data from previous research in other regions. Improvements in the quality and availability of ADR reports are urgently needed. 相似文献