全文获取类型
| 收费全文 | 767886篇 |
| 免费 | 53604篇 |
| 国内免费 | 1440篇 |
专业分类
| 耳鼻咽喉 | 10007篇 |
| 儿科学 | 24658篇 |
| 妇产科学 | 18893篇 |
| 基础医学 | 118795篇 |
| 口腔科学 | 22399篇 |
| 临床医学 | 68627篇 |
| 内科学 | 150119篇 |
| 皮肤病学 | 17716篇 |
| 神经病学 | 55023篇 |
| 特种医学 | 27188篇 |
| 外国民族医学 | 76篇 |
| 外科学 | 113088篇 |
| 综合类 | 15092篇 |
| 现状与发展 | 2篇 |
| 一般理论 | 185篇 |
| 预防医学 | 56870篇 |
| 眼科学 | 17505篇 |
| 药学 | 58077篇 |
| 3篇 | |
| 中国医学 | 2583篇 |
| 肿瘤学 | 46024篇 |
出版年
| 2021年 | 6502篇 |
| 2019年 | 6566篇 |
| 2018年 | 9833篇 |
| 2017年 | 7285篇 |
| 2016年 | 8087篇 |
| 2015年 | 9494篇 |
| 2014年 | 12237篇 |
| 2013年 | 18263篇 |
| 2012年 | 26008篇 |
| 2011年 | 26907篇 |
| 2010年 | 15213篇 |
| 2009年 | 13774篇 |
| 2008年 | 24606篇 |
| 2007年 | 26282篇 |
| 2006年 | 26870篇 |
| 2005年 | 25096篇 |
| 2004年 | 24189篇 |
| 2003年 | 22708篇 |
| 2002年 | 22124篇 |
| 2001年 | 37633篇 |
| 2000年 | 38667篇 |
| 1999年 | 31247篇 |
| 1998年 | 8076篇 |
| 1997年 | 6807篇 |
| 1996年 | 7114篇 |
| 1995年 | 6764篇 |
| 1994年 | 6205篇 |
| 1992年 | 23084篇 |
| 1991年 | 23035篇 |
| 1990年 | 22380篇 |
| 1989年 | 22151篇 |
| 1988年 | 20089篇 |
| 1987年 | 19464篇 |
| 1986年 | 18531篇 |
| 1985年 | 17378篇 |
| 1984年 | 12787篇 |
| 1983年 | 10798篇 |
| 1982年 | 5995篇 |
| 1979年 | 11561篇 |
| 1978年 | 8165篇 |
| 1977年 | 6868篇 |
| 1976年 | 6625篇 |
| 1975年 | 7289篇 |
| 1974年 | 8532篇 |
| 1973年 | 8168篇 |
| 1972年 | 7664篇 |
| 1971年 | 7139篇 |
| 1970年 | 6889篇 |
| 1969年 | 6319篇 |
| 1968年 | 5782篇 |
排序方式： 共有10000条查询结果，搜索用时 5 毫秒
91.
92.
93.
94.
95.
96.
97.
Imre W.K. Kouw Bart B.L. Groen Joey S.J. Smeets Irene Fleur Kramer Janneau M.X. van Kranenburg Rachél Nilwik Jan A.P. Geurts René H.M. ten Broeke Martijn Poeze Luc J.C. van Loon Lex B. Verdijk 《Journal of the American Medical Directors Association》2019,20(1):35-42
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98.
99.
100.
Oga Emmanuel. A. Peters Erica. N. Mark Katrina Trocin Kathleen Coleman-Cowger Victoria. H. 《Maternal and child health journal》2019,23(2):250-257
Maternal and Child Health Journal - Background Prenatal substance use screening is recommended. The 4 P’s Plus screener includes questions on perceived problematic substance use in parents... 相似文献