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   8667篇
  免费   703篇
  国内免费   26篇
耳鼻咽喉   79篇
儿科学   306篇
妇产科学   212篇
基础医学   1028篇
口腔科学   87篇
临床医学   1457篇
内科学   1470篇
皮肤病学   104篇
神经病学   855篇
特种医学   318篇
外科学   936篇
综合类   271篇
一般理论   6篇
预防医学   1027篇
眼科学   78篇
药学   618篇
中国医学   5篇
肿瘤学   539篇
  2022年   52篇
  2021年   141篇
  2020年   90篇
  2019年   151篇
  2018年   163篇
  2017年   134篇
  2016年   138篇
  2015年   160篇
  2014年   207篇
  2013年   386篇
  2012年   543篇
  2011年   528篇
  2010年   287篇
  2009年   241篇
  2008年   506篇
  2007年   489篇
  2006年   492篇
  2005年   530篇
  2004年   480篇
  2003年   496篇
  2002年   488篇
  2001年   150篇
  2000年   153篇
  1999年   154篇
  1998年   113篇
  1997年   74篇
  1996年   60篇
  1995年   69篇
  1994年   53篇
  1992年   101篇
  1991年   78篇
  1990年   75篇
  1989年   88篇
  1988年   95篇
  1987年   103篇
  1986年   76篇
  1985年   84篇
  1984年   74篇
  1983年   74篇
  1982年   56篇
  1981年   60篇
  1980年   47篇
  1979年   76篇
  1978年   61篇
  1974年   56篇
  1973年   71篇
  1972年   70篇
  1971年   59篇
  1970年   44篇
  1969年   41篇
排序方式: 共有9396条查询结果,搜索用时 15 毫秒
1.
2.

Background

The purpose of the study was to evaluate the association between fetal echocardiographic measurements and the need for intervention (primary coarctation repair, staged coarctation repair, or catheter intervention) in prenatally diagnosed coarctation of the aorta.

Methods

A single-centre retrospective cohort study (2005-2015) of 107 fetuses diagnosed with suspected coarctation of the aorta in the setting of an apex-forming left ventricle and antegrade flow across the mitral and aortic valves.

Results

Median gestational age at diagnosis was 32 weeks (interquartile range, 23-35 weeks). Fifty-six (52%) did not require any neonatal intervention, 51 patients (48%) underwent a biventricular repair. In univariable analysis, an increase in ascending aorta (AAo) peak Doppler flow velocity (odds ratio [OR], 1.40 [95% confidence interval [CI], 1.05-1.91] per 20 cm/s; P = 0.03) was associated with intervention. No intervention was associated with larger isthmus size (OR, 0.23; P < 0.001), transverse arch diameter (OR, 0.23; P < 0.001), and aortic (OR, 0.72; P = 0.02), mitral (OR, 0.58; P = 0.001), and AAo (OR, 0.53; P < 0.001) z-scores. In multivariable analysis, higher peak AAo Doppler (OR, 2.51 [95% CI, 1.54-4.58] per 20 cm/s; P = 0.001) and younger gestational age at diagnosis (OR, 0.81 [95% CI, 0.70-0.93] per week; P = 0.005) were associated with intervention, whereas a higher AAo z-score (OR, 0.65 [95% CI, 0.43-0.94] per z; P = 0.029) and transverse arch dimension (OR, 0.44 [95% CI, 0.18-0.97]; P = 0.05) decreased the risk of intervention.

Conclusions

In prenatally suspected coarctation, the variables associated with intervention comprised smaller AAo and transverse arch size, earlier gestational age at diagnosis, and the additional finding of a higher peak AAo Doppler.  相似文献   
3.
4.
For many parents stopping life-sustaining medical treatment on their dying infant is psychologically impossible. Dostoevsky's insights into human behavior, particularly the fact that individuals do not want the anxiety and guilt associated with responsibility for making difficult decisions, might change the way physicians approach parents for permission to withdraw life-prolonging medical interventions on dying infants.  相似文献   
5.
6.
7.
8.
9.
Diabetic neuropathic foot ulcers and amputation   总被引:2,自引:0,他引:2  
A neuropathic foot ulcer is a severe complication of diabetes that can result in a more severe complication, a lower extremity amputation. We conducted a cohort study of 24,616 individuals with a diabetic neuropathic foot ulcer treated within a multicenter wound care network. A total of 1653 (6.7%) individuals had an amputation and 46.3% of these amputations were of a toe or ray (minor amputation). In the more than 10-year follow-up period that we studied, the percentage of those who had an amputation varied between 5.6% and 8.4%. Of those who had an amputation, the percentage that had a minor amputation increased over time from 4.0% in the earliest years to more than 60% in the later years of observation. The single most important determinant of amputation was the observation of fascia, tendon, and bone at the initial assessment. In conclusion, about 7% of those with a diabetic neuropathic foot ulcer will have an amputation and in the past 10 years there has been a remarkable increase in the number of minor as compared to major amputations.  相似文献   
10.
BACKGROUND: Telekid Care is a project that attempts to overcome the health and educational barriers faced by children in urban Kansas City, Kansas. Telemedicine units were placed in school nurses' offices and linked to physicians at the University of Kansas Medical Center (KUMC). This paper describes the development of this project, presents utilization data, and discuss the lessons learned from the application of telemedicine in a school setting. RESULTS: Project developers spent 11 months designing the protocol and procedures for a pilot test. Four elementary schools participated, and 187 consultations were conducted. The most common reason for consultation was ear, nose, and throat (ENT) problems, making up 28% of all consults. Mandatory school physical examinations and dermatology problems combined to make up an additional 40% of the consults. The average time that elapsed between the request for a consult and confirmation of an appointment was 23 minutes. When immediate service was requested, 85% of the consults occurred the day of the request. These results strongly demonstrate telemedicine's ability to offer immediate service to children in need. CONCLUSION: Telemedicine enabled underserved inner-city children to gain access to health services. This service was most effective when it was integrated into the delivery system. Furthermore, community groups strongly favored the project, positively influencing its acceptance as an innovative health care delivery system.  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