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   2784篇
  免费   296篇
  国内免费   20篇
耳鼻咽喉   17篇
儿科学   89篇
妇产科学   101篇
基础医学   303篇
口腔科学   84篇
临床医学   328篇
内科学   506篇
皮肤病学   21篇
神经病学   170篇
特种医学   231篇
外科学   297篇
综合类   124篇
一般理论   2篇
预防医学   265篇
眼科学   196篇
药学   242篇
  1篇
肿瘤学   123篇
  2022年   21篇
  2021年   38篇
  2020年   18篇
  2019年   34篇
  2018年   35篇
  2017年   28篇
  2016年   25篇
  2015年   44篇
  2014年   50篇
  2013年   82篇
  2012年   126篇
  2011年   145篇
  2010年   79篇
  2009年   79篇
  2008年   114篇
  2007年   115篇
  2006年   126篇
  2005年   98篇
  2004年   106篇
  2003年   82篇
  2002年   88篇
  2001年   73篇
  2000年   78篇
  1999年   81篇
  1998年   41篇
  1997年   56篇
  1996年   42篇
  1995年   42篇
  1994年   46篇
  1993年   49篇
  1992年   56篇
  1991年   47篇
  1990年   42篇
  1989年   61篇
  1988年   53篇
  1987年   68篇
  1986年   68篇
  1985年   80篇
  1984年   44篇
  1983年   32篇
  1982年   28篇
  1981年   31篇
  1980年   25篇
  1979年   38篇
  1978年   29篇
  1977年   20篇
  1973年   18篇
  1972年   25篇
  1969年   20篇
  1929年   17篇
排序方式: 共有3100条查询结果,搜索用时 8 毫秒
1.
2.
3.
4.
5.
In 1993, a case-control study by the Health and Safety Executive (HSE) assessed the risk of leukaemia and non-Hodgkin's lymphoma (LNHL) among children of fathers employed at the Sellafield nuclear installation in relation to paternal preconceptional irradiation (PPI). It concluded that the statistical association between risk of LNHL and PPI was confined to children born in the village of Seascale, where the dose-response was extremely high and very significant. In contrast, in 2002, a Cumbrian birth cohort study, investigating largely the same cases, concluded that this statistical association was not significantly different among children born inside and outside Seascale and estimated the dose-response inside Seascale to be much lower. This review makes a detailed comparison of the two studies, considering their design, data and analyses. The differences between their findings are due to: (i) differences in the distribution of offspring-years which are differential with respect to dose category and Seascale birth status, (ii) a non-Seascale high-dose case included in the Cumbrian but not the HSE study, (iii) differences between analyses using categorical and continuous PPI dose and (iv) the presence of Seascale controls with PPI over 200 mSv in the Cumbrian but not the HSE study.  相似文献   
6.
Somatization disorder in a family practice   总被引:4,自引:0,他引:4  
Somatization disorder is a condition characterized by multiple unexplained complaints. This study was done to determine the prevalence of somatization disorder in a family practice office setting, to characterize the patients so affected, and to assess their impact on the practice. A sample of ill patients was interviewed, of whom 6 (5 percent) had definite somatization disorder and another 4 (4 percent) had borderline somatization disorder (ten or more symptoms). All were women, and they were more likely than controls to live in households with children but no spouse (P less than .01). They were also more likely than their unaffected counterparts to be from the lowest two social classes (P less than .01). Compared with matched controls, their rate of office visits and charges incurred was about 50 percent greater (.58 visits per month vs .41 visits per month; $23.28 per month vs $14.44 per month). Their charts were thicker (7 cm vs 3.6 cm) and heavier (3076 g vs 1843 g) and had more diagnoses (85 vs 51) than controls. The physicians of the somatizers were significantly less satisfied with the care rendered to them than to the controls (P less than .01). This study demonstrates that somatization disorder is a prevalent, expensive, and difficult problem for family physicians.  相似文献   
7.
The degree of nodal involvement in a consecutive series of 400 patients with invasive ductal breast cancer is presented. A positive correlation was observed between the number of metastatic nodes identified and the number of axillary nodes examined for poorly but not moderately differentiated tumours. The relevance of this observation to breast cancer trials is discussed.  相似文献   
8.
9.
SRTR Center-Specific Reporting Tools: Posttransplant Outcomes   总被引:3,自引:2,他引:1  
Measuring and monitoring performance—be it waiting list and posttransplant outcomes by a transplant center, or organ donation success by an organ procurement organization and its partnering hospitals—is an important component of ensuring good care for people with end-stage organ failure. Many parties have an interest in examining these outcomes, from patients and their families to payers such as insurance companies or the Centers for Medicare and Medicaid Services; from primary caregivers providing patient counseling to government agencies charged with protecting patients.
The Scientific Registry of Transplant Recipients produces regular, public reports on the performance of transplant centers and organ procurement organizations. This article explains the statistical tools used to prepare these reports, with a focus on graft survival and patient survival rates of transplant centers—especially the methods used to fairly and usefully compare outcomes of centers that serve different populations. The article concludes with a practical application of these statistics—their use in screening transplant center performance to identify centers that may need remedial action by the OPTN/UNOS Membership and Professional Standards Committee.  相似文献   
10.
Transplant data: sources, collection and research considerations, 2004   总被引:9,自引:9,他引:0  
The process of collecting and analyzing transplant data is complex. Familiarity with how these data are collected is crucial to a thorough understanding of the information. This article focuses on available OPTN-SRTR data and the continuing evolution of data collection mechanisms; how that data collection system is improving the data quality and reducing the data collection burden; how additional ascertainment of outcomes both completes and validates existing data; and caveats that remain for researchers. This year's article focuses further on research considerations related to cohort choice, timing of data submission, and potential biases in follow-up data. Ongoing improvements in data collection timeliness and scope are covered. The impact of extra ascertainment of outcomes, particularly for post-transplant kidney graft failure from Medicare data, are also examined. A section on graft failure reporting among different sources traces the steps by which the SRTR reconciles different data sources in its analyses. It is important that those reading and conducting transplant research understand the origin, structure, and scope of the available data. All of these issues should be carefully considered when choosing cohorts and data sources for analysis.  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