全文获取类型
收费全文 | 10587篇 |
免费 | 797篇 |
国内免费 | 35篇 |
专业分类
耳鼻咽喉 | 118篇 |
儿科学 | 249篇 |
妇产科学 | 452篇 |
基础医学 | 1359篇 |
口腔科学 | 1067篇 |
临床医学 | 1411篇 |
内科学 | 1930篇 |
皮肤病学 | 250篇 |
神经病学 | 561篇 |
特种医学 | 434篇 |
外科学 | 961篇 |
综合类 | 101篇 |
一般理论 | 3篇 |
预防医学 | 1030篇 |
眼科学 | 283篇 |
药学 | 690篇 |
中国医学 | 107篇 |
肿瘤学 | 413篇 |
出版年
2023年 | 127篇 |
2022年 | 199篇 |
2021年 | 361篇 |
2020年 | 249篇 |
2019年 | 325篇 |
2018年 | 424篇 |
2017年 | 319篇 |
2016年 | 352篇 |
2015年 | 435篇 |
2014年 | 523篇 |
2013年 | 580篇 |
2012年 | 803篇 |
2011年 | 826篇 |
2010年 | 484篇 |
2009年 | 424篇 |
2008年 | 567篇 |
2007年 | 562篇 |
2006年 | 465篇 |
2005年 | 379篇 |
2004年 | 411篇 |
2003年 | 308篇 |
2002年 | 240篇 |
2001年 | 188篇 |
2000年 | 139篇 |
1999年 | 172篇 |
1998年 | 151篇 |
1997年 | 139篇 |
1996年 | 127篇 |
1995年 | 114篇 |
1994年 | 75篇 |
1993年 | 59篇 |
1992年 | 62篇 |
1991年 | 67篇 |
1990年 | 54篇 |
1989年 | 74篇 |
1988年 | 78篇 |
1987年 | 68篇 |
1986年 | 64篇 |
1985年 | 63篇 |
1984年 | 30篇 |
1983年 | 37篇 |
1982年 | 27篇 |
1981年 | 22篇 |
1980年 | 27篇 |
1978年 | 26篇 |
1977年 | 21篇 |
1976年 | 25篇 |
1975年 | 25篇 |
1974年 | 14篇 |
1973年 | 18篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
Zinc sulfate addition to glass-ionomer-based cements: influence on physical and antibacterial properties, zinc and fluoride release. 总被引:5,自引:0,他引:5
Prudencio W R Osinaga Rosa Helena M Grande Rafael Y Ballester Maria Regina L Simionato Célia Regina M Delgado Rodrigues Antonio Muench 《Dental materials》2003,19(3):212-217
OBJECTIVES: The aim of this study is to evaluate the effect of ZnSO(4) addition to a conventional glass ionomer and a resin-modified glass ionomer on solubility, flexural strength, zinc and fluoride (F) release, and Streptococcus mutans growth inhibition. METHODS: 5 or 10% ZnSO(4) was added to Vitremer and Ketac-Fil powders. Solubility test was performed based on ISO 7489. Flexural strength was determined by 3-point bending test based on ISO 4049. Zn release/uptake was determined by atomic emission spectrometry; F release/uptake was measured using a F-specific electrode. Both release measurements were performed for 15 d before and 15 d after recharging. Antibacterial test was conducted according to agar plate methods against S. mutans, by measuring the inhibition halos in 1-h and 15-d specimens. Data were analyzed by ANOVA. RESULTS: Solubility increased with higher ZnSO(4) content, but remained below the ISO 7489 limit. Flexural strength was not affected by ZnSO(4) addition, and Vitremer performed better than Ketac-Fil. The control materials released no zinc. Vitremer with 10% ZnSO(4) released the highest amount of zinc. Fluoride release was similar for Ketac-Fil and Vitremer. In both cases, the highest amounts were released in the first 24 h. The growth inhibition halo of S. mutans was similar for both materials with highest content of ZnSO(4) and occurred only with 1-h specimens. SIGNIFICANCE: Zinc addition decreased microorganisms growth and improved fluoride release, without significantly affecting the materials' flexural strength and solubility. 相似文献
9.
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
10.
Sandeep Gohar Devendra Desai Anand Joshi Anita Bhaduri Ramesh Deshpande C Balkrishna Mukesh Chawla Camila Rodrigues V R Joshi 《Indian journal of gastroenterology》2003,22(4):140-142
INTRODUCTION: Autoimmune hepatitis (AIH) is a well-defined entity in the West but there are sparse Indian data on this disease. AIM: To study the clinical profile and response to treatment of Indian patients with AIH. METHODS: This is a part retrospective and part prospective study of 50 patients (median age 48 years, range 11-82; 43 women) seen between 1995 to 2001, diagnosed to have AIH as per the revised scoring system. Clinical and laboratory profile, response to treatment, and complications of treatment were analyzed. RESULTS: AIH accounted for 6% of all patients with liver disease seen during the period. The presenting symptoms were gastrointestinal in 43 and non-gastrointestinal in 7, with median symptom duration of 6 months (range 2 weeks to 40 years). Forty patients (80%) had chronic liver disease. Associated illnesses were present in 28 patients. Twenty-six patients were classified as definite and the rest as probable AIH. Forty-nine patients had Type 1 AIH. Five patients had overlap syndrome. Forty-five patients (90%) received immunosuppressive therapy. Twelve of 18 patients receiving only prednisolone and 21 of 27 patients receiving prednisolone and azathioprine combination responded. Thirteen (26%) patients had therapy-related complications (infectious 5, non infectious 8) with two treatment-related deaths. CONCLUSION: Type 1 AIH was the predominant type of AIH. The majority of patients with AIH presented with chronic liver disease. There was good response to immunosuppressive therapy. Therapy-related complications occurred in one-fourth of patients. 相似文献