首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2442642篇
  免费   201222篇
  国内免费   8229篇
耳鼻咽喉   32089篇
儿科学   80597篇
妇产科学   68530篇
基础医学   341260篇
口腔科学   66893篇
临床医学   222314篇
内科学   492160篇
皮肤病学   57914篇
神经病学   203152篇
特种医学   96411篇
外国民族医学   708篇
外科学   371643篇
综合类   58285篇
现状与发展   4篇
一般理论   836篇
预防医学   196737篇
眼科学   54269篇
药学   171672篇
  6篇
中国医学   5026篇
肿瘤学   131587篇
  2018年   26728篇
  2017年   20674篇
  2016年   24042篇
  2015年   26878篇
  2014年   37932篇
  2013年   56764篇
  2012年   73159篇
  2011年   78346篇
  2010年   47479篇
  2009年   45721篇
  2008年   72780篇
  2007年   77201篇
  2006年   78394篇
  2005年   76048篇
  2004年   72675篇
  2003年   69871篇
  2002年   66956篇
  2001年   118810篇
  2000年   121826篇
  1999年   101498篇
  1998年   30007篇
  1997年   27017篇
  1996年   27774篇
  1995年   27158篇
  1994年   25004篇
  1993年   23511篇
  1992年   80431篇
  1991年   77608篇
  1990年   74554篇
  1989年   71026篇
  1988年   65588篇
  1987年   64258篇
  1986年   60401篇
  1985年   58033篇
  1984年   44297篇
  1983年   37424篇
  1982年   23216篇
  1981年   20791篇
  1980年   19316篇
  1979年   39656篇
  1978年   28416篇
  1977年   23808篇
  1976年   22094篇
  1975年   22887篇
  1974年   27179篇
  1973年   26147篇
  1972年   24420篇
  1971年   22372篇
  1970年   20890篇
  1969年   19447篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
Introduction: The Hedgehog (HH) pathway constitutes a collection of signaling molecules which critically influence embryogenesis. In adults, however, the HH pathway remains integral to the proliferation, maintenance, and apoptosis of adult stem cells including hematopoietic stem cells.

Areas covered: We discuss the current understanding of the HH pathway as it relates to normal hematopoiesis, the pathology of acute myeloid leukemia (AML), the rationale for and data from combination therapies including HH pathway inhibitors, and ultimately the prospects that might offer promise in targeting this pathway in AML.

Expert opinion: Efforts to target the HH pathway have been focused on impeding this disposition and restoring chemosensitivity to conventional myeloid neoplasm therapies. The year 2018 saw the first approval of a HH pathway inhibitor (glasdegib) for AML, though for an older population and in combination with an uncommonly-used therapy. Several other clinical trials with agents targeting modulators of HH signaling in AML and MDS are underway. Further study and understanding of the interplay between the numerous aspects of HH signaling and how it relates to the augmented survival of AML will provide a more reliable substrate for therapeutic strategies in patients with this poor-risk disease.  相似文献   

32.
33.
BackgroundThe aim of this study was to estimate the prevalence of dental prosthetic treatment and to investigate the demographic, social, economic and medical factors associated with the use of fixed and removable dentures in a representative sample of adults living in France.MethodsThe data were obtained from the 2002–2003 Decennial Health Survey, a cross-sectional study of a representative sample of the population living in France, which included 29,679 adults. Information was collected by interview. The variables collected were fixed denture, removable denture, age, gender, number of children, area of residence, nationality, educational attainment, family social status, employment status, annual household income per capita, supplementary insurance, chronic disease, eyesight problems/glasses, hearing problems/hearing aids. Multinomial logistic regression models were used to study the relationship between prosthetic treatment and demographic, socioeconomic and medical characteristics unadjusted, adjusted for age and adjusted for all the characteristics.ResultsThe prevalence of prosthetic treatment was 34.6% (95% confidence interval (CI): [34.1; 35.2]) for fixed prosthetic dentures and 13.8% (95% CI: [13.4; 14.2]) for removable prosthetic dentures. We showed a gradient between educational attainment and removable dentures; the odds ratio adjusted for all the variables (aOR) associated with no or primary education compared to post-secondary education was 2.56; 95% CI: [2.09; 3.13]. When annual household income per capita was low, subjects were less likely to report fixed dentures (aOR = 0.68; 95% CI: [0.62; 0.75]) than those with high annual household income per capita. Individuals without insurance less often reported fixed dentures than those with private insurance. Those reporting chronic disease were less likely to report fixed dentures (aOR = 0.87; 95% CI: [0.79; 0.95]) but more likely to report removable dentures (aOR = 1.29; 95% CI: [1.17; 1.43]) than those without chronic disease.ConclusionThis study reveals social, economic and medical inequalities in fixed and removable prosthetic treatment among adults in France.  相似文献   
34.
35.
ABSTRACT

This project examined 55 picture books featuring transgender, gender expansive or genderqueer protagonists or narrators published between 2008 and 2018. The purpose of the study was to determine how this genre of children’s literature supports and challenges four gender assumptions: the gender binary, gender essentialism, sex/gender congruency and gender stability. Additionally, this critical analysis explored misgendering within this genre and themes of social rejection and acceptance. Protagonists and narrators were permitted a degree of gender nonconformity, however, the majority of picture books missed opportunities for a more complete exploration of gender possibilities.  相似文献   
36.
37.

Objectives

To determine: (i) the behaviour change techniques used by a sample of Australian physiotherapists to promote non-treatment physical activity; and (ii) whether those behaviour change techniques are different to the techniques used to encourage adherence to rehabilitation exercises.

Design

Cross-sectional survey.

Method

An online self-report survey was advertised to private practice and outpatient physiotherapists treating patients with musculoskeletal conditions. The use of 50 behaviour change techniques were measured using five-point Likert-type scale questions.

Results

Four-hundred and eighty-six physiotherapists responded to the survey, with 216 surveys fully completed. Most respondents (85.1%) promoted non-treatment physical activity often or all of the time. Respondents frequently used 29 behaviour change techniques to promote non-treatment physical activity or encourage adherence to rehabilitation exercises. A similar number of behaviour change techniques was frequently used to encourage adherence to rehabilitation exercises (n = 28) and promote non-treatment physical activity (n = 26). Half of the behaviour change techniques included in the survey were frequently used for both promoting non-treatment physical activity and encouraging adherence to rehabilitation exercises (n = 25). Graded tasks was the most, and punishment was the least, frequently reported technique used to promote non-treatment physical activity and encourage adherence to rehabilitation exercises.

Conclusions

Respondents reported using similar behaviour change techniques to promote non-treatment physical activity and encourage adherence to rehabilitation exercises. The variability in behaviour change technique use suggests the behaviour the physiotherapist is promoting influences their behaviour change technique choice. Including the frequently-used behaviour change techniques in non-treatment physical activity promotion interventions might improve their efficacy.  相似文献   
38.
39.
40.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号