全文获取类型
收费全文 | 98926篇 |
免费 | 29442篇 |
国内免费 | 1066篇 |
专业分类
耳鼻咽喉 | 2431篇 |
儿科学 | 2621篇 |
妇产科学 | 2346篇 |
基础医学 | 2746篇 |
口腔科学 | 5049篇 |
临床医学 | 26134篇 |
内科学 | 24641篇 |
皮肤病学 | 3260篇 |
神经病学 | 12365篇 |
特种医学 | 3614篇 |
外科学 | 17727篇 |
综合类 | 187篇 |
现状与发展 | 40篇 |
一般理论 | 4篇 |
预防医学 | 13720篇 |
眼科学 | 2223篇 |
药学 | 1329篇 |
中国医学 | 34篇 |
肿瘤学 | 8963篇 |
出版年
2024年 | 746篇 |
2023年 | 5032篇 |
2022年 | 1110篇 |
2021年 | 2748篇 |
2020年 | 5345篇 |
2019年 | 2014篇 |
2018年 | 6891篇 |
2017年 | 7338篇 |
2016年 | 7920篇 |
2015年 | 8003篇 |
2014年 | 10415篇 |
2013年 | 12133篇 |
2012年 | 3858篇 |
2011年 | 3542篇 |
2010年 | 6811篇 |
2009年 | 9090篇 |
2008年 | 3516篇 |
2007年 | 2476篇 |
2006年 | 3572篇 |
2005年 | 2179篇 |
2004年 | 1592篇 |
2003年 | 1217篇 |
2002年 | 1162篇 |
2001年 | 1837篇 |
2000年 | 1173篇 |
1999年 | 1699篇 |
1998年 | 2088篇 |
1997年 | 1909篇 |
1996年 | 1956篇 |
1995年 | 1692篇 |
1994年 | 1103篇 |
1993年 | 937篇 |
1992年 | 766篇 |
1991年 | 659篇 |
1990年 | 551篇 |
1989年 | 559篇 |
1988年 | 529篇 |
1987年 | 401篇 |
1986年 | 377篇 |
1985年 | 314篇 |
1984年 | 286篇 |
1983年 | 325篇 |
1982年 | 244篇 |
1981年 | 212篇 |
1980年 | 138篇 |
1978年 | 134篇 |
1977年 | 130篇 |
1976年 | 100篇 |
1974年 | 83篇 |
1972年 | 82篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
33.
Robert P. Kusy BS MS PhD 《American journal of orthodontics and dentofacial orthopedics》2004,125(6):726-732
Using an earlier model, which described the critical contact angle for binding from second-order angulation alone, a more generalized model is derived that combines the effects of angulation and torque. From this vantage point, the onset of binding is evaluated for 3 scenarios: second-order angulation alone, third-order torque only, and a combination of second-order angulation and third-order torque. These scenarios are detailed by plotting the critical contact angle for binding against the torque angle as a function of 10 wire dimensions (16 x 16, 16 x 22, 17 x 17, 17 x 22, 17 x 25, 18 x 18, 18 x 22, 18 x 25, 19 x 25, and 21 x 25 mil), 4 bracket widths (70, 100, 130, and 160 mil), and 4 bracket slots (18, 20.5, 22, and 24.5 mil). From these plots, we learn that each wire base dimension (eg, an 18-mil base as found in 18 x 18-mil, 18 x 22-mil and 18 x 25-mil archwires) has a common maximum critical contact angle for binding. Moreover, each wire-slot combination has a common maximum torque angle, which is independent of bracket width. Finally, we learn that archwire-bracket combinations that use a metric 0.5-mm slot might have some advantages with regard to torquing--given the current philosophy that light, continuous forces are more favorable. 相似文献
34.
35.
36.
David H. Wilson Catherine R. Chittleborough Kerry Kirke Janet F. Grant Richard E. Ruffin 《Sozial- und Pr?ventivmedizin》2004,13(5):406-412
Objectives: Heavy smokers are a segment of the smoking population who are at increased risk of smoking-related morbidity and least likely to achieve cessation. This study identifies the impact of heavy smoking on quality of life by gender and describes the subpopulation for improved targeting.Methods: South Australian representative population data (n = 3010) was used to compare the health-related quality of life status of male and female heavy smokers as assessed by the SF-36. 相似文献
37.
Salwa AlDahlawi BDS MSc ; Ameneh Eslami MD ; Lari Häkkinen DDS PhD ; Hannu S. Larjava DDS PhD 《Wound repair and regeneration》2006,14(3):289-297
The alphavbeta6 integrin is an exclusively epithelial integrin that is highly expressed during fetal development. In adult tissue, alphavbeta6 integrin is expressed during inflammation, carcinogenesis, and in wound healing. We previously reported that alphavbeta6 integrin is highly expressed in poorly healing human wounds and its over-expression is associated with chronic wounds in a mouse model. The objective of this study was to investigate the role of alphavbeta6 integrin in compromised wound healing induced by hydrocortisone treatment or aging by using young and old mice deficient in or overexpressing the beta6 integrin subunit in the epidermis. Untreated aged beta6 integrin-deficient (beta6-/-) animals showed a significant delay in wound healing when compared to their age-matched controls or younger beta6-/- mice. The most significant delay was observed at the stages where granulation tissue deposition was occurring. Hydrocortisone treatment significantly delayed wound healing in wild-type and beta6 integrin-deficient mice in comparison with the untreated controls. However, hydrocortisone treatment in beta6 integrin overexpressing animals did not cause a significant delay in wound healing. The results of this study suggest that alphavbeta6 integrin plays an important role in wound healing in animals compromised by either age or stress mimicked by hydrocortisone. 相似文献
38.
39.
Qualitative Data Analysis: An Introduction 总被引:1,自引:1,他引:0
40.
PROBLEM: Recent developments in providing care to children with emotional and behavioral disorders, especially those with serious emotional disturbance, have included the establishment of systems of care. Guided by a set of principles and values, these systems of care have organized and delivered services to children and families with complex needs. To date, nurses have not had a salient role in systems of care. RESULTS: It is estimated that 20% of American children and adolescents have an emotional or mental disorder. As many as two thirds of these children are not receiving services. Systems of care have been funded to provide services for these children, particularly for the most severely affected. To date, nursing has not had a prominent role in these systems of care. CONCLUSIONS: Based on their knowledge, skills, and holistic approach to care, nurses could better integrate nursing care into systems of care. Possible roles as case managers, primary therapists, in-home interventionists, and in educational programs are suggested. 相似文献