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   15866篇
  免费   1013篇
  国内免费   91篇
耳鼻咽喉   210篇
儿科学   466篇
妇产科学   392篇
基础医学   1742篇
口腔科学   536篇
临床医学   1390篇
内科学   3482篇
皮肤病学   397篇
神经病学   1131篇
特种医学   600篇
外国民族医学   2篇
外科学   2695篇
综合类   233篇
一般理论   11篇
预防医学   993篇
眼科学   557篇
药学   1158篇
中国医学   106篇
肿瘤学   869篇
  2024年   11篇
  2023年   190篇
  2022年   162篇
  2021年   744篇
  2020年   496篇
  2019年   661篇
  2018年   736篇
  2017年   513篇
  2016年   599篇
  2015年   584篇
  2014年   840篇
  2013年   985篇
  2012年   1504篇
  2011年   1482篇
  2010年   857篇
  2009年   673篇
  2008年   1017篇
  2007年   980篇
  2006年   763篇
  2005年   674篇
  2004年   547篇
  2003年   532篇
  2002年   428篇
  2001年   116篇
  2000年   94篇
  1999年   100篇
  1998年   61篇
  1997年   55篇
  1996年   53篇
  1995年   37篇
  1994年   31篇
  1993年   40篇
  1992年   25篇
  1991年   37篇
  1990年   33篇
  1989年   25篇
  1988年   34篇
  1987年   23篇
  1986年   18篇
  1985年   31篇
  1984年   27篇
  1983年   15篇
  1982年   18篇
  1981年   15篇
  1980年   10篇
  1979年   13篇
  1978年   13篇
  1977年   10篇
  1975年   12篇
  1974年   13篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Akteure der öffentlichen Gesundheit (Public Health) tragen wesentlich zu Gesundheitsschutz, -förderung und...  相似文献   
2.
3.
4.
Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital condition. It responds well to early diagnosis and treatment, but otherwise the prognosis is poor. We present our case series of 12 patients (mean age, 2 ± 2.58 yr; age range, 2 mo–8 yr), emphasizing the diagnostic process and discussing our surgical results. The diagnosis of ALCAPA should be suspected in infants who have dilated cardiomyopathy with electrocardiographic changes that suggest ischemia, and in older children who have isolated mitral regurgitation. When clinical suspicion is high, the results of 2-dimensional echocardiography combined with color-flow Doppler studies in expert hands can establish the diagnosis, thus avoiding angiography in critically ill infants. The treatment of choice in our patients was transfer and reimplantation of the left coronary artery onto the ascending aorta. There were 2 deaths: both were infants in extremis who underwent emergency surgery. An older child with severe ventricular dysfunction was given mechanical ventricular assistance and then heart transplantation. As of this report, all 10 survivors remained well and asymptomatic.  相似文献   
5.
6.
The floating metacarpal bone is a result of simultaneous fracture-dislocation of both carpometacarpal and metacarpophalangeal joints. This rare entity may be associated with other hand injuries. Here we present a floating index metacarpal with concomitant 3rd–5th carpometacarpal fracture-dislocations. Excellent functional short-term result was achieved after open metacarpopha langeal reduction and closed carpometacarpal reduction and percutaneous pinning.  相似文献   
7.
8.

Background and study aims

Acute upper gastrointestinal bleeding is one of the main causes of hospitalisation. The purpose of this study was to determine the prognostic factors in non-variceal upper gastrointestinal bleeding.

Patients and methods

Clinical outcomes, demographic and laboratory variables of the subjects were collected from the HIS software and national code with the SQL format from three hospitals in Qazvin. The data were linked to the database software designed by the author. Clinical and upper endoscopic findings of patients’ records were collected through a questionnaire form in the designed software database.

Results

In this study, 29.2% of patients with favourable outcome and 64.2% of patients with unfavourable clinical outcomes had a history of anticoagulant drug use before hospitalisation (p?<?0.001). The prevalence of chronic cardiovascular disease, chronic liver disease, chronic lung disease, diabetes and dialysis was higher in subjects with poor clinical outcomes than those with a favourable clinical outcome.53.1% of subjects with favourable clinical outcome and 90.5% of subjects with undesirable clinical outcomes received packed red blood cell transfusion (p?<?0.001). 16.1% of subjects with desirable clinical outcome and 86.3% of subjects with undesirable clinical outcomes received endoscopic haemostatic treatment which was statistically significant (p?<?0.001).

Conclusion

Undesirable clinical outcome in patients with acute non-variceal upper gastrointestinal bleeding has a significant statistical association with longer hospitalisation, chronic underlying disease, anticoagulant administration, packed red blood cell infusion, higher Forrest stage, low systolic blood pressure, higher age, low haemoglobin, low platelet count, high INR and high BUN at the onset of diagnosis.  相似文献   
9.
10.
Several regulatory bodies have agreed that low-dose radiation used in medical imaging is a weak carcinogen that follows a linear, non-threshold model of cancer risk. While avoiding radiation is the best course of action to mitigate risk, computed tomography (CT) scans are often critical for diagnosis. In addition to the as low as reasonably achievable principle, a more concrete method of dose reduction for common CT imaging exams is the use of a diagnostic reference level (DRL). This paper examines Canada's national DRL values from the recent CT survey and compares it to published provincial DRLs as well as the DRLs in the United Kingdom and the United States of America for the 3 most common CT exams: head, chest, and abdomen/pelvis. Canada compares well on the international scale, but it should consider using more electronic dose monitoring solutions to create a culture of dose optimization.  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