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   477篇
  免费   27篇
  国内免费   11篇
耳鼻咽喉   1篇
儿科学   29篇
妇产科学   2篇
基础医学   45篇
口腔科学   2篇
临床医学   45篇
内科学   129篇
皮肤病学   7篇
神经病学   7篇
特种医学   132篇
外科学   33篇
综合类   34篇
预防医学   12篇
眼科学   2篇
药学   15篇
中国医学   3篇
肿瘤学   17篇
  2020年   4篇
  2019年   6篇
  2018年   10篇
  2017年   1篇
  2016年   4篇
  2015年   6篇
  2014年   8篇
  2013年   21篇
  2012年   10篇
  2011年   10篇
  2010年   12篇
  2009年   19篇
  2008年   22篇
  2007年   18篇
  2006年   12篇
  2005年   13篇
  2004年   15篇
  2003年   9篇
  2002年   10篇
  2001年   14篇
  2000年   8篇
  1999年   5篇
  1998年   40篇
  1997年   33篇
  1996年   19篇
  1995年   14篇
  1994年   15篇
  1993年   15篇
  1992年   2篇
  1991年   2篇
  1990年   10篇
  1989年   10篇
  1988年   11篇
  1987年   11篇
  1986年   13篇
  1985年   15篇
  1984年   4篇
  1983年   5篇
  1982年   10篇
  1981年   7篇
  1980年   10篇
  1978年   9篇
  1977年   7篇
  1976年   4篇
  1975年   3篇
  1972年   1篇
  1968年   2篇
  1967年   1篇
  1965年   1篇
  1962年   1篇
排序方式: 共有515条查询结果,搜索用时 0 毫秒
31.
32.
Long-term results of the lateral tunnel Fontan operation   总被引:11,自引:0,他引:11  
OBJECTIVES: Completion of a total cavopulmonary anastomosis with an intra-atrial lateral tunnel is known to yield good early and midterm results. In this study, we sought to determine the long-term outcome (10 years) after a lateral tunnel Fontan procedure. METHODS: Between October 1987 and December 1991, 220 patients (aged 11 months to 32 years) with a wide range of underlying diagnoses underwent a fenestrated or nonfenestrated lateral tunnel Fontan procedure at our institution. Current follow-up information was available for 196 patients (94%, mean follow-up = 10.2 +/- 0.6 years). Risk factor analysis included patient-related and procedure-related variables, with death, failure, and bradyarrhythmia or tachyarrhythmia as outcome parameters. RESULTS: There were 12 early deaths (<30 days or hospital death), 7 late deaths, 4 successful takedown operations, and 4 heart transplantations. Kaplan-Meier estimated survival was 93% at 5 years and 91% at 10 years, and freedom from failure was 90% at 5 years and 87% at 10 years. Freedom from new supraventricular tachyarrhythmia was 96% at 5 years and 91% at 10 years; freedom from new bradyarrhythmia was 88% at 5 years and 79% at 10 years. Three patients had evidence of protein-losing enteropathy. Multivariable risk factors for development of supraventricular tachyarrhythmia included heterotaxy syndrome, atrioventricular valve abnormalities, and preoperative bradyarrhythmia. Risk factors for bradyarrhythmia included systemic venous anomalies. The sole risk factor for late failure was a previous coarctation repair. CONCLUSION: The lateral tunnel Fontan procedure results in excellent long-term outcome even when used in patients with diverse anatomic diagnoses. The incidence of atrial tachyarrhythmia is low and mainly depends on the underlying cardiac morphology and preoperative arrhythmia. The good long-term outcome after an intracardiac lateral tunnel Fontan procedure should serve as a basis for comparison with other surgical alternatives.  相似文献   
33.
Recent reports have demonstrated that the HIV-1 transactivator protein,tat, induces apoptosis in T-lymphocyte cell lines, as well as in peripheral blood mononuclear cells, and stimulates a cascade of events resulting in up-regulation of the potent immunosuppressive cytokine, transforming growth factor-β (TGF-β). In this study we evaluated the ability of TGF-β to mediatetat induced apoptosis in T-lymphocyte cell lines. T-cells treated exogenously with either TGF-β1 or a combination of tat and pan-specific TGF-β neutralizing antibodies showed little change in the amount of apoptosis. When treated with pan-specific TGF-β neutralizing antibodies, Jurkat cells that stably expresstat protein (Jurkat-tat) showed only a modest decrease in apoptosis, while CEM-TART cells (CEM T-cells expressing both HIV-1tat andrev) demonstrated little change in the amount of apoptosis. In conclusion, we have demonstrated that TGF-β does not play a significant role in mediatingtat induced T-cell apoptosis.  相似文献   
34.
35.
36.
We report 4 cases of congenital and acquired coronary sinus ostial atresia incidentally found during electrophysiologic assessment for supraventricular arrhythmias. Congenital variants consisted of coronary sinus drainage predominantly via persistent left superior vena cavae and partial coronary sinus unroofing into the left atrium. The acquired variant was inadvertently produced during surgery for cor triatriatum. A variety of electrophysiologic substrates including right and left-sided accessory pathways and both typical and atypical AV nodal reciprocating tachycardia were identified. Approaches to imaging and accessing the coronary sinus when the os cannot be cannulated are discussed, including a search for right atrial accessory venous collaterals, venography to rule-out a persistent left superior vena cava, and coronary angiography.  相似文献   
37.

Background  

The question of the protective effect of breastfeeding on development of asthma has raised substantial interest, but the scientific evidence of the optimal duration of breastfeeding is controversial.  相似文献   
38.
39.
The thermal balance of 13 term infants was measured in a closed-circuit metabolism chamber. Each was studied naked, then with a gamgee-lined hat, and finally with a 'cummerbund' made of a similar material and of similar dimensions. At 27 degrees C the oxygen consumption of the 'hatted' babies was only 85% and the total heat loss 75% of the values measured with the infants naked. The cummerbund offered no detectable benefit. An additional 10 infants were studied while wearing a tubegauze hat at environmental temperatures of 28.5 (+/- 0.5) degrees C. This type of hat gave no measurable thermal protection. It is concluded that a substantial reduction of thermal stress in adverse environments can be achieved simply and clearly by adequately covering the vault of the skull.  相似文献   
40.
In 3 infants functional intestinal obstruction, associated with a short small intestine, malrotation, and pyloric hypertrophy, was shown to be due to failure of development of the argyrophil myenteric plexus, with the absence of ongoing peristalsis. 4 infants with similar clinical features have been described previously, and there is evidence for an autosomal recessive mode of inheritance of this syndrome.  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