全文获取类型
收费全文 | 3266篇 |
免费 | 188篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 216篇 |
妇产科学 | 60篇 |
基础医学 | 408篇 |
口腔科学 | 72篇 |
临床医学 | 364篇 |
内科学 | 713篇 |
皮肤病学 | 88篇 |
神经病学 | 171篇 |
特种医学 | 430篇 |
外科学 | 316篇 |
综合类 | 51篇 |
预防医学 | 182篇 |
眼科学 | 70篇 |
药学 | 196篇 |
2篇 | |
中国医学 | 2篇 |
肿瘤学 | 185篇 |
出版年
2022年 | 15篇 |
2021年 | 26篇 |
2020年 | 24篇 |
2019年 | 42篇 |
2018年 | 44篇 |
2017年 | 45篇 |
2016年 | 43篇 |
2015年 | 63篇 |
2014年 | 77篇 |
2013年 | 122篇 |
2012年 | 103篇 |
2011年 | 115篇 |
2010年 | 129篇 |
2009年 | 111篇 |
2008年 | 109篇 |
2007年 | 119篇 |
2006年 | 96篇 |
2005年 | 100篇 |
2004年 | 82篇 |
2003年 | 75篇 |
2002年 | 72篇 |
2001年 | 83篇 |
2000年 | 71篇 |
1999年 | 87篇 |
1998年 | 142篇 |
1997年 | 185篇 |
1996年 | 141篇 |
1995年 | 118篇 |
1994年 | 125篇 |
1993年 | 103篇 |
1992年 | 46篇 |
1991年 | 54篇 |
1990年 | 56篇 |
1989年 | 69篇 |
1988年 | 56篇 |
1987年 | 46篇 |
1986年 | 63篇 |
1985年 | 56篇 |
1984年 | 35篇 |
1983年 | 25篇 |
1982年 | 31篇 |
1981年 | 32篇 |
1980年 | 28篇 |
1979年 | 25篇 |
1978年 | 18篇 |
1977年 | 32篇 |
1976年 | 37篇 |
1975年 | 26篇 |
1973年 | 15篇 |
1970年 | 10篇 |
排序方式: 共有3534条查询结果,搜索用时 15 毫秒
101.
W. Andonotopo M. Stanojevic A. Kurjak G. Azumendi JM Carrera 《The Ultrasound Review of Obstetrics & Gynecology》2004,4(2):103-114
The aim of this paper was to review the clinical applications of four-dimensional ultrasonography in the assessment of fetal behavior. With the use of a computerized database, articles on three-dimensional ultrasonography were reviewed. Several applications of dynamic three-dimensional ultrasonography have been reported, including imaging of fetal movements, facial expression and fetal hand movements. The importance of the assessment of fetal behavior by four-dimensional sonography is stressed. Four-dimensional sonography seems to be a useful imaging tool for clinical problem solving in perinatology, especially in observing the development of the central nervous system in utero. 相似文献
102.
103.
104.
105.
Katelynn Toomer Kimberly Sauls Diana Fulmer Lilong Guo Kelsey Moore Janiece Glover Rebecca Stairley Joyce Bischoff Robert A. Levine Russell A. Norris 《Anatomical record (Hoboken, N.J. : 2007)》2019,302(1):117-124
Mitral valve prolapse (MVP) affects 2.4% of the population and has poorly understood etiology. Recent genetic studies have begun to unravel the complexities of MVP and through these efforts, mutations in the FLNA (Filamin-A) gene were identified as disease causing. Our in vivo and in vitro studies have validated these genetic findings and have revealed FLNA as a central regulator of valve morphogenesis. The mechanisms by which FLNA mutations result in myxomatous mitral valve disease are currently unknown, but may involve proteins previously associated with mutated regions of the FLNA protein, such as the small GTPase signaling protein, R-Ras. Herein, we report that Filamin-A is required for R-Ras expression and activation of the Ras–Mek–Erk pathway. Loss of the Ras/Erk pathway correlated with hyperactivation of pSmad2/3, increased extracellular matrix (ECM) production and enlarged mitral valves. Analyses of integrin receptors in the mitral valve revealed that Filamin-A was required for β1-integrin expression and provided a potential mechanism for impaired ECM compaction and valve enlargement. Our data support Filamin-A as a protein that regulates the balance between Erk and Smad activation and an inability of Filamin-A deficient valve interstitial cells to effectively remodel the increased ECM production through a β1-integrin mechanism. As a consequence, loss of Filamin-A function results in increased ECM production and generation of a myxomatous phenotype characterized by improperly compacted mitral valve tissue. Anat Rec, 302:117–124, 2019. © 2018 Wiley Periodicals, Inc. 相似文献
106.
SB Cho JH Kim S Cho JM Park YK Park SH Oh 《Journal of the European Academy of Dermatology and Venereology》2011,25(1):64-67
Background The clinical characteristics of vitiligo in children and adolescents with an emphasis on thyroid dysfunction have only been reported in a few studies. Objective The purpose of this study was to examine the characteristics of children and adolescents with vitiligo and compare the incidence of thyroid dysfunction between them and controls without vitiligo at the same age. Methods A retrospective analysis of 324 Korean children and adolescents with vitiligo was performed. The results of thyroid function screening tests in them (n = 254) were compared with controls (n = 122). Results Of the total 324 children and adolescents with vitiligo, vitiligo vulgaris was the most common type (42.3%) and the most commonly involved site was the face (54.6%). A total of 15 of 254 (5.9%) patients screened for thyroid function were diagnosed with thyroid disease (four had Hashimoto’s thyroiditis; two, Graves’ disease; seven, subclinical hypothyroidism; and two, subclinical hyperthyroidism). None of the 50 patients with segmental vitiligo showed any thyroid dysfunction (P = 0.047). There was no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group, in which seven of 122 (5.7%) showed thyroid dysfunction. Conclusion In this study, we demonstrated the characteristics of children and adolescents with vitiligo and also observed no significant difference in the incidence of thyroid disease between children and adolescents with vitiligo and the control group. 相似文献
107.
108.
Better understanding of proximal tibia morphology can lead to improvements in total knee arthroplasty (TKA) through development of tibial tray families that adequately reflect the diversity of global anatomy using an appropriate number of components. We quantified variations in proximal tibial morphology at the TKA level and characterized differences attributable to gender and ethnicity. Virtual TKA was performed on digital models of 347 tibiae, spanning both genders and multiple ethnicities. The geometry of the resection profile was quantified using both a comprehensive set of morphological measurements (reflecting size and shape) and principal component analysis (PCA). The dominant statistical modes of variation were associated primarily with size (plateau dimensions, radii, and area), with lesser contributions associated with asymmetry and aspect ratios. Medial and lateral AP dimensions were strongly correlated with plateau ML width, with minimal differences in correlations due to gender or ethnicity. In conclusion, clinically relevant differences in proximal tibia morphology at the level of TKA resections across genders and multiple ethnicities can be attributed largely to variations in overall proximal tibial size, not gender‐ or ethnic‐specific shape variations. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1643–1652, 2013 相似文献
109.
110.