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   785篇
  免费   44篇
  国内免费   1篇
耳鼻咽喉   34篇
儿科学   43篇
妇产科学   7篇
基础医学   87篇
口腔科学   9篇
临床医学   36篇
内科学   94篇
皮肤病学   22篇
神经病学   155篇
特种医学   91篇
外科学   47篇
综合类   16篇
预防医学   21篇
眼科学   13篇
药学   88篇
肿瘤学   67篇
  2023年   3篇
  2022年   4篇
  2021年   10篇
  2020年   13篇
  2019年   17篇
  2018年   25篇
  2017年   20篇
  2016年   26篇
  2015年   15篇
  2014年   20篇
  2013年   32篇
  2012年   29篇
  2011年   32篇
  2010年   18篇
  2009年   19篇
  2008年   30篇
  2007年   39篇
  2006年   40篇
  2005年   53篇
  2004年   41篇
  2003年   38篇
  2002年   19篇
  2001年   27篇
  2000年   26篇
  1999年   25篇
  1998年   18篇
  1997年   16篇
  1996年   15篇
  1995年   17篇
  1994年   9篇
  1993年   19篇
  1992年   9篇
  1991年   6篇
  1990年   7篇
  1989年   9篇
  1988年   12篇
  1987年   11篇
  1986年   8篇
  1985年   6篇
  1984年   4篇
  1983年   4篇
  1982年   4篇
  1981年   3篇
  1980年   3篇
  1979年   4篇
  1978年   4篇
  1977年   5篇
  1973年   4篇
  1972年   3篇
  1971年   3篇
排序方式: 共有830条查询结果,搜索用时 421 毫秒
21.
Introduction. In a previous study (Silverstein, Bakshi, Chapman, & Nowlis, 1998a, Cognitive Neuropsychiatry) we demonstrated that while schizophrenia patients showed similar learning curves as nonpatient controls when determining whether a configural pattern of elements has been seen before or not, they did not demonstrate any learning curve with nonconfigural stimuli (in contrast to controls). Methodological limitations of that study, however, precluded generalisability of those effects.Methods. In the present study, therefore, different groups of schizophrenia patients (n = 18) and controls (n = 22) were administered a modified version of the familiarity judgement task used in Silverstein et al. (1998a). In the new version of the task: (1) the patterns that repeated were different for each participant; and (2) half of the nonrepeating patterns were configural and half were nonconfigural.Results. These indicated stronger perceptual learning effects for the configural compared to the nonconfigural patterns, and overall better performance and more pronounced learning effects for the control group.Conclusions. The data provide further evidence for a schizophrenia-related impairment in perceptual organisation and in the ability to develop memory representations for novel stimuli.  相似文献   
22.
23.
24.

Background

Two decades of research has established the positive effect of using patient-targeted decision support interventions: patients gain knowledge, greater understanding of probabilities and increased confidence in decisions. Yet, despite their efficacy, the effectiveness of these decision support interventions in routine practice has yet to be established; widespread adoption has not occurred. The aim of this review was to search for and analyze the findings of published peer-reviewed studies that investigated the success levels of strategies or methods where attempts were made to implement patient-targeted decision support interventions into routine clinical settings.

Methods

An electronic search strategy was devised and adapted for the following databases: ASSIA, CINAHL, Embase, HMIC, Medline, Medline-in-process, OpenSIGLE, PsycINFO, Scopus, Social Services Abstracts, and the Web of Science. In addition, we used snowballing techniques. Studies were included after dual independent assessment.

Results

After assessment, 5322 abstracts yielded 51 articles for consideration. After examining full-texts, 17 studies were included and subjected to data extraction. The approach used in all studies was one where clinicians and their staff used a referral model, asking eligible patients to use decision support. The results point to significant challenges to the implementation of patient decision support using this model, including indifference on the part of health care professionals. This indifference stemmed from a reported lack of confidence in the content of decision support interventions and concern about disruption to established workflows, ultimately contributing to organizational inertia regarding their adoption.

Conclusions

It seems too early to make firm recommendations about how best to implement patient decision support into routine practice because approaches that use a ‘referral model’ consistently report difficulties. We sense that the underlying issues that militate against the use of patient decision support and, more generally, limit the adoption of shared decision making, are under-investigated and under-specified. Future reports from implementation studies could be improved by following guidelines, for example the SQUIRE proposals, and by adopting methods that would be able to go beyond the ‘barriers’ and ‘facilitators’ approach to understand more about the nature of professional and organizational resistance to these tools. The lack of incentives that reward the use of these interventions needs to be considered as a significant impediment.
  相似文献   
25.
26.
27.
28.
Feeding is a rhythmic behavior that consists of several component cycle types. How the timing of these cycles changes over a complete feeding sequence is not well known. To test the hypothesis that cycle frequency/duration changes as a function of time spent feeding, we examined complete feeding sequences in six infant pigs, using EMG of mylohyoid and thyrohyoid as cycle markers. We measured the instantaneous frequency of sucking and of swallowing cycles in 19 sequences. Each sequence contained three qualitatively distinctive phases of sucking frequency. Phase 1 started with cycles at a very high frequency and quickly dropped to a more constant level with low variation, which characterized phase 2. Phase 3 had a steady level of frequency but was interspersed with a number of high- or low-frequency cycles. Each phase differed from the others in patterns of within-phase variation and among-phase variation. Phase 2 had the least variation, and phase 3 had the largest range of frequencies. The number of sucks per swallow also differed among phases. These patterns, which characterize normative feeding, could indicate a physiologic basis in satiation. In human infant clinical studies, where data collection is often limited, these results indicated the utility of collecting data in different phases. Finally, these results can be used as a template or pattern with which to assess clinically compromised infants.  相似文献   
29.
Genetic polymorphisms in the methylene tetrahydrofolate reductase (MTHFR) gene have been associated with the development of acute leukemias and various malignancies. The role of MTHFR polymorphism in the development of pediatric acute lymphoblastic leukemia (ALL) has been extensively studied among north Indians in various settings, yet its association with acute leukemias remains unresolved. To evaluate the relationship between functional MTHFR polymorphisms, C677T and A1298C and possible effect on risk of ALL in adults and children in North Indian population by comparing them with healthy controls. DNA was isolated from peripheral blood of 184 ALL patients (33 adults, 151 children) and 155 controls and analyzed by a PCR-restriction fragment length polymorphism assay. The frequency of MTHFR 677CT and 1298 AC genotypes were significantly lower among adult ALL cases when compared to the controls. We found a 1.74-fold reduced risk of ALL in individuals with 1298AC polymorphic variant and a 9.17-fold decreased risk of adult ALL. However, no statistically significant difference was evident between the above polymorphisms and susceptibility to ALL in children. Polymorphisms in the MTHFR gene possibly modulate risk of ALL in north Indian adults but not in children, although larger studies are needed.  相似文献   
30.
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