全文获取类型
收费全文 | 4472篇 |
免费 | 598篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 44篇 |
儿科学 | 129篇 |
妇产科学 | 343篇 |
基础医学 | 432篇 |
口腔科学 | 71篇 |
临床医学 | 1131篇 |
内科学 | 724篇 |
皮肤病学 | 84篇 |
神经病学 | 331篇 |
特种医学 | 309篇 |
外科学 | 458篇 |
综合类 | 116篇 |
一般理论 | 2篇 |
预防医学 | 327篇 |
眼科学 | 62篇 |
药学 | 288篇 |
中国医学 | 5篇 |
肿瘤学 | 223篇 |
出版年
2023年 | 52篇 |
2022年 | 27篇 |
2021年 | 49篇 |
2020年 | 60篇 |
2019年 | 70篇 |
2018年 | 118篇 |
2017年 | 132篇 |
2016年 | 127篇 |
2015年 | 161篇 |
2014年 | 180篇 |
2013年 | 202篇 |
2012年 | 176篇 |
2011年 | 192篇 |
2010年 | 179篇 |
2009年 | 177篇 |
2008年 | 169篇 |
2007年 | 183篇 |
2006年 | 193篇 |
2005年 | 159篇 |
2004年 | 121篇 |
2003年 | 126篇 |
2002年 | 119篇 |
2001年 | 125篇 |
2000年 | 112篇 |
1999年 | 120篇 |
1998年 | 123篇 |
1997年 | 151篇 |
1996年 | 122篇 |
1995年 | 120篇 |
1994年 | 81篇 |
1993年 | 81篇 |
1992年 | 72篇 |
1991年 | 91篇 |
1990年 | 55篇 |
1989年 | 94篇 |
1988年 | 98篇 |
1987年 | 66篇 |
1986年 | 73篇 |
1985年 | 67篇 |
1984年 | 48篇 |
1983年 | 42篇 |
1982年 | 28篇 |
1981年 | 26篇 |
1980年 | 25篇 |
1978年 | 36篇 |
1977年 | 27篇 |
1976年 | 26篇 |
1975年 | 19篇 |
1973年 | 18篇 |
1967年 | 23篇 |
排序方式: 共有5079条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
5.
Colin J McKay 《World journal of surgery》2006,30(12):2234-2235
6.
7.
8.
Massachusetts State Program for the Care of Prematures 总被引:2,自引:0,他引:2
McKay FL 《American journal of public health and the nation's health》1941,31(1):72-78
9.
Peripheral quantitative computed tomography in children and adolescents: the 2007 ISCD Pediatric Official Positions 总被引:2,自引:0,他引:2
Babette Zemel Shona Bass Teresa Binkley Gaele Ducher Heather Macdonald Heather McKay Laurie Moyer-Mileur John Shepherd Bonny Specker Kate Ward Didier Hans 《Journal of clinical densitometry》2008,11(1):59-74
Peripheral quantitative computed tomography (pQCT) has mainly been used as a research tool in children. To evaluate the clinical utility of pQCT and formulate recommendations for its use in children, the International Society of Clinical Densitometry (ISCD) convened a task force to review the literature and propose areas of consensus and future research. The types of pQCT technology available, the clinical application of pQCT for bone health assessment in children, the important elements to be included in a pQCT report, and quality control monitoring techniques were evaluated. The review revealed a lack of standardization of pQCT techniques, and a paucity of data regarding differences between pQCT manufacturers, models and software versions and their impact in pediatric assessment. Measurement sites varied across studies. Adequate reference data, a critical element for interpretation of pQCT results, were entirely lacking, although some comparative data on healthy children were available. The elements of the pQCT clinical report and quality control procedures are similar to those recommended for dual-energy X-ray absorptiometry. Future research is needed to establish evidence-based criteria for the selection of the measurement site, scan acquisition and analysis parameters, and outcome measures. Reference data that sufficiently characterize the normal range of variability in the population also need to be established. 相似文献
10.