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   32107篇
  免费   1829篇
  国内免费   100篇
耳鼻咽喉   252篇
儿科学   1095篇
妇产科学   927篇
基础医学   3606篇
口腔科学   397篇
临床医学   5855篇
内科学   5413篇
皮肤病学   358篇
神经病学   3123篇
特种医学   607篇
外国民族医学   1篇
外科学   3076篇
综合类   304篇
现状与发展   1篇
一般理论   50篇
预防医学   4469篇
眼科学   445篇
药学   1865篇
中国医学   36篇
肿瘤学   2156篇
  2023年   193篇
  2022年   326篇
  2021年   589篇
  2020年   425篇
  2019年   654篇
  2018年   810篇
  2017年   563篇
  2016年   640篇
  2015年   671篇
  2014年   996篇
  2013年   1603篇
  2012年   2307篇
  2011年   2435篇
  2010年   1290篇
  2009年   1137篇
  2008年   2213篇
  2007年   2416篇
  2006年   2287篇
  2005年   2217篇
  2004年   2039篇
  2003年   1964篇
  2002年   1890篇
  2001年   237篇
  2000年   195篇
  1999年   289篇
  1998年   371篇
  1997年   312篇
  1996年   251篇
  1995年   276篇
  1994年   213篇
  1993年   212篇
  1992年   138篇
  1991年   144篇
  1990年   140篇
  1989年   113篇
  1988年   103篇
  1987年   99篇
  1986年   95篇
  1985年   105篇
  1984年   124篇
  1983年   127篇
  1982年   144篇
  1981年   139篇
  1980年   118篇
  1979年   57篇
  1978年   71篇
  1977年   63篇
  1976年   48篇
  1975年   37篇
  1974年   40篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
52.
53.
We identified 18 patients with double-orifice mitral valve (DOMV) and intact atrioventricular (AV) septum out of 40,179 echocardiographic studies performed between 1997 and 2002 at Children's Hospital, Denver, CO. In this study we describe (1) the anatomic characteristics of the DOMV in the absence of AV septal defect, (2) the function of the mitral valve by spectral and color Doppler flow mapping, and (3) associated lesions. The topographic location of the orifices in the leaflets suggests possible embryologic mechanisms of DOMV. In this series, DOMV was most commonly associated with left-sided obstructive lesions (in 39% of patients). Spectral and color Doppler interrogation demonstrated a normal flow profile in most cases; only 2 patients had significant mitral regurgitation or stenosis. Therefore, due to the uncertain natural history of this lesion and the potential need for endocarditis prophylaxis, careful imaging of the mitral valve is recommended, particularly in the presence of left-sided obstructive lesions.  相似文献   
54.
Poverty influences health status, life expectancy, health behaviours, and use of health services. This study examined factors influencing the use of health-related services by people living in poverty. In the first phase, 199 impoverished users of health-related services in 2 large Canadian cities were interviewed by their peers. In the second phase, group interviews with people living in poverty (n = 52) were conducted. Data were analyzed using thematic content analysis. Diverse health-related services were used to meet basic and health needs, to maintain human contact, and to cope with life's challenges. Use of services depended on proximity, affordability, convenience, information, and providers' attitudes and behaviours. Use was impeded by inequities based on income status. To promote the health of people living in poverty, nurses and other health professionals can enhance the accessibility and quality of services, improve their interactions with people living in poverty, provide information about available programs, offer coordinated community-based services, collaborate with other sectors, and advocate for more equitable services and policies.  相似文献   
55.
An ex post facto correlational study was conducted to examine predictors of quality of life in persons 3 to 6 months after a myocardial infarction. Self-care resources, self-care knowledge (needs), activity level, and selected demographic variables were examined as predictor variables. A convenience sample of 86 subjects with a mean age of 61 years, was recruited for participation in this study. The study that explained 35% of the variance in quality of life included self-care resources available, activity level, and self-care needs. Modeling and Role Modeling Paradigm provided a useful explanation of how self-care resources and self-care knowledge can be applied to persons recovering from myocardial infarction.  相似文献   
56.
A patient-centered paradigm for clinical research and medical care is presented as a solution to the problem of declining innovation and increasing costs and development time in the pipeline for new therapies. Fundamental differences in values and motivations among scientists, clinicians, industry sponsor, and patients in neurotherapeutics provide a framework for analysis of ethical conflicts and the loss of public confidence in medical research. Parkinson advocates’ views on clinical trial participation, perceived risks and benefits, placebo controls, and sham surgery are presented. These views reflect the sense of urgency and the unique perspective that comes from living with this progressive, debilitating condition full time. A patient-centered paradigm that includes authentic voices of patients as collaborators at every stage of development will help to resolve conflicts, build trust, recruit trial participants, and accelerate new therapies. Key elements are adaptive clinical trial methods and the development of information technology for the assessment of outcomes and surveillance of safety over the life cycle of a medical product. Supported by the Parkinson’s Disease Foundation, the Parkinson Pipeline Project is a grassroots group of Parkinson’s patients whose goal is to represent an authentic voice for patients in the treatment development process. This group promotes education and communication between members of the Parkinson’s community and active stakeholders in medical research, industry, and regulatory agencies. Its members are an example of a new breed of knowledgeable consumers, armed with first-hand access to research findings and reinforced by on-line connections to like-minded peers throughout the world.  相似文献   
57.
Society is currently on the threshold of a new revolution in understanding the interaction of genes and the environment. This research has profound implications for understanding occupational disease and will present ethical challenges to occupational health practice. The public must be educated about the potential promise, as well as the threats, posed by emerging genetic technologies.  相似文献   
58.
The expansion of women in the military is reshaping the veteran population, with women now constituting the fastest growing segment of eligible VA health care users. In recognition of the changing demographics and special health care needs of women, the VA Office of Research & Development recently sponsored the first national VA Women’s Health Research Agenda-setting conference to map research priorities to the needs of women veterans and position VA as a national leader in Women’s Health Research. This paper summarizes the process and outcomes of this effort, outlining VA’s research priorities for biomedical, clinical, rehabilitation, and health services research.  相似文献   
59.
60.
Postpartum weight, body mass index (BMI), triceps skinfold thicknesses (TSF) and upper arm circumferences (AC) were measured bimonthly for 24 months in a large cohort of urban and rural Filipino women. Weight loss, leading to an increasing prevalence of low BMI (<18.5) is the norm in this population where dietary intakes of energy, calcium, and iron fall below WHO recommended intakes. The effects of lactation on postpartum changes in weight and TSF during 6-month intervals were examined by stratifying women into groups defined by lactation duration. In addition, multivariate models were used to examine the effects of lactation on changes in weight or TSF while controlling for other factors such as energy intake, seasonality, morbidity, pregnancy interval, parity, and age. Lactation was associated with significantly increased weight losses from birth to 18 months postpartum. Furthermore, full lactation (breast-feeding with the addition of less than 20 kcal/day to the infant's diet) also significantly increased weight loss in the first 6 months, when the overall duration of lactation in that interval was controlled. Lactation had a small but statistically significant effect on changes in TSF as well. © 1992 Wiley-Liss, Inc.  相似文献   
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