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   939篇
  免费   59篇
  国内免费   5篇
耳鼻咽喉   3篇
儿科学   24篇
妇产科学   26篇
基础医学   104篇
口腔科学   12篇
临床医学   125篇
内科学   229篇
皮肤病学   5篇
神经病学   103篇
特种医学   11篇
外科学   87篇
综合类   14篇
一般理论   14篇
预防医学   175篇
眼科学   6篇
药学   35篇
中国医学   4篇
肿瘤学   26篇
  2023年   3篇
  2022年   31篇
  2021年   26篇
  2020年   19篇
  2019年   28篇
  2018年   31篇
  2017年   21篇
  2016年   17篇
  2015年   23篇
  2014年   19篇
  2013年   50篇
  2012年   65篇
  2011年   62篇
  2010年   36篇
  2009年   43篇
  2008年   56篇
  2007年   62篇
  2006年   60篇
  2005年   45篇
  2004年   54篇
  2003年   53篇
  2002年   49篇
  2001年   17篇
  2000年   9篇
  1999年   12篇
  1998年   6篇
  1997年   7篇
  1996年   4篇
  1995年   10篇
  1993年   6篇
  1992年   8篇
  1991年   4篇
  1990年   8篇
  1989年   8篇
  1988年   2篇
  1987年   4篇
  1986年   4篇
  1985年   4篇
  1984年   2篇
  1983年   3篇
  1982年   2篇
  1981年   3篇
  1980年   5篇
  1979年   2篇
  1977年   2篇
  1973年   2篇
  1966年   2篇
  1955年   1篇
  1946年   1篇
  1932年   1篇
排序方式: 共有1003条查询结果,搜索用时 15 毫秒
71.
Developing systems of care for children with emotional disorders requires changes in the organization and delivery of services. Using concept mapping, the authors conducted a study to define factors of a community’s readiness to make such changes. Participants were from 25 of 27 federally-funded, advanced sites, plus a panel of experts. The participants completed three tasks: brainstorming, rating, and sorting. This process produced eight factors: Leadership, Network of Local Partners, Shared Goals, Collaboration, Families and Youth as Partners, Accountability, Evaluation, and Plans to Expand Services. Understanding factors that contribute to successful implementation should help communities identify and make needed changes.  相似文献   
72.
Scientific Inquiry provides a forum to facilitate the ongoing process of questioning and evaluating practice, presents informed practice based on available data, and innovates new practices through research and experimental learning.  相似文献   
73.
Although manufacturers' compliance tables of stent delivery balloons indicate the diameter of the balloon at a given inflation pressure, it is unclear whether these data correlate with in vivo true intracoronary balloon diameters (TBDs). The TBDs of two new-generation balloon-expandable stent delivery systems (Duet and NIR) were measured by quantitative coronary analysis (QCA) in 100 consecutive patients. The manufacturers' stated balloon diameter (BD) of the stent delivery systems overestimated the TBD in 94% +/- 4% of patients receiving both Duet or NIR stent implantations. In only 6% of the patients, the TBD matched the manufacturers' stated balloon diameter. There was no underestimation of TBDs by both manufacturers' compliance tables. The Duet tables overestimated TBDs by 14% +/- 8% (range, 1%-36%), the NIR tables by 18% +/- 8% (range, 1%-41%), P < 0.05, Duet vs. NIR, respectively. When the manufacturers' data were corrected for the differences in reporting data from in vitro tests, i.e., balloon compliance data with or without the stent, the degree of overestimation of diameters was similar for Duet and NIR stent delivery balloons (14% +/- 8% vs. 13% +/- 7%, Duet vs. NIR; P = NS). Manufacturers' compliance tables of both the Duet and NIR stent delivery balloon systems significantly overestimate the true intracoronary balloon diameter. The manufacturers' of stent delivery balloons should clearly state on the box, if balloon compliance data were derived from in vitro bench testing, which phantoms were used for compliance analysis, and that the tables may overestimate the true intracoronary balloon diameter. The findings of the present study have important clinical implications with respect to performing coronary stent implantation with precision.  相似文献   
74.
75.
76.
77.
This paper examined the reliability, convergent validity and factor structure of the self-report Screen for Child Anxiety Disorders (SCARED; Birmaher et al. in J Am Acad Child Adolesc Psychiatry 36:545–553, 1997) in a large community sample of children and adolescents in Saudi Arabia. The questionnaire showed moderate to high internal consistency and satisfactory test–retest reliability over a 2 week period. In addition, there were significant positive correlations between reported anxiety symptoms with parent report behavioural difficulties. The five factor structure model of the SCARED also had a good model fit in this population. The results showed that self-report anxiety symptoms decreased with age (for boys and not girls) and were higher in adolescent girls. The results suggest that the SCARED could be useful in this population to identify individuals who are at risk of developing anxiety disorders in childhood with a view to implementing prevention and intervention methods to ensure positive developmental outcome over time.  相似文献   
78.
79.

Objectives

To define the prevalence of various ranges of the ratio of partial arterial oxygen tension to fraction of inspired oxygen (Pao2/Fio2) and to determine correlative and predictive variables of donor lung Pao2/Fio2.

Material and Methods

From the brain death database of Masih Daneshvari Hospital Organ Procurement Center, we extracted demographic data, cause of injury, patient clinical condition, and laboratory findings as independent data. Donor lung suitability was determined with an oxygen challenge test, with results of 400 mm Hg considered ideal; 300 to 399 mm Hg, good; 200 to 299 mm Hg, borderline; and less than 200 mm Hg, not acceptable.

Results

Using the Pao2/Fio2 cutoff points, 6.7% of donor lungs were considered ideal; 26.7%, good; 40%, borderline; and 26.7%, unacceptable. Mean (SD; range) Pao2/Fio2 was 266.6 (85.6; 110-460). The Pao2/Fio2 was significantly correlated with age (r = −0.35; P = .02). After entering the study variables into a linear regression model, age (−2.3; P = .008) and sex (51.5; P = .04) were significant predictors of donor lung suitability (R2 = 0.95; P < .001).

Conclusion

Results of oxygen challenge tests demonstrated better suitability of lungs from male and younger brain-dead donors. This finding is independent of other variables including cause of brain death and clinical and paraclinical data.  相似文献   
80.
Administrative issues related to operating child and adolescent psychiatry programs or child mental health centers are substantially different than their adult counterpart programs. The increasing demands from managed care and other regulatory agencies make these programs difficult to operate. The smaller scale of these programs and the fewer existing programs make managing access to care more complicated. The administrators and clinicians in these programs have to be vigilant of legal responsibilities and reporting mandates that child practitioners and agencies that treat children need to abide by. In order to continue thriving, programs need to be efficient and fiscally viable. Issues such as building the continuum of care and finding the qualified personnel to staff these services are discussed in this article.  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