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   427篇
  免费   22篇
耳鼻咽喉   5篇
儿科学   8篇
妇产科学   6篇
基础医学   70篇
口腔科学   6篇
临床医学   37篇
内科学   98篇
皮肤病学   15篇
神经病学   32篇
特种医学   10篇
外科学   104篇
综合类   5篇
预防医学   16篇
眼科学   15篇
药学   10篇
肿瘤学   12篇
  2024年   1篇
  2023年   4篇
  2022年   11篇
  2021年   12篇
  2020年   6篇
  2019年   9篇
  2018年   14篇
  2017年   14篇
  2016年   9篇
  2015年   14篇
  2014年   17篇
  2013年   11篇
  2012年   39篇
  2011年   37篇
  2010年   24篇
  2009年   19篇
  2008年   29篇
  2007年   26篇
  2006年   17篇
  2005年   14篇
  2004年   16篇
  2003年   12篇
  2002年   14篇
  2001年   9篇
  2000年   11篇
  1999年   10篇
  1998年   9篇
  1996年   7篇
  1995年   2篇
  1994年   4篇
  1992年   4篇
  1991年   3篇
  1989年   3篇
  1988年   3篇
  1986年   1篇
  1985年   1篇
  1984年   1篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1979年   1篇
  1978年   3篇
  1977年   1篇
  1976年   1篇
  1972年   1篇
  1970年   1篇
  1966年   1篇
排序方式: 共有449条查询结果,搜索用时 15 毫秒
441.
We present a rare case of left ventricular to right atrial communication, a Gerbode type defect discovered in an adult female, originally misinterpreted as pulmonary arterial hypertension. The case report will be followed by the review of the literature and a discussion about how to prevent echocardiographic misinterpretation of this defect as pulmonary arterial hypertension using careful echocardiographic examination.  相似文献   
442.
443.

Background  

The antibacterial, antifungal and probable anti-inflammatory effects of menthol were evaluated in the treatment of napkin dermatitis (ND).  相似文献   
444.

Background

Per oral endoscopic myotomy (POEM) is a viable alternative to standard Heller myotomy for surgical treatment of achalasia. Outcomes from the United States, Europe and Asia have been reported. We sought to report data after the initiation of POEM in a Canadian centre.

Methods

We enrolled patients with achalasia in a research ethics board–approved pilot study. Surgeons learned the POEM procedure in a systematic manner that included visiting experts in POEM, practice in an animal laboratory and mentoring from POEM experts. Preoperative evaluation included manometry, 24-hour pH, barium swallow, endoscopy and Eckhardt Symptom Score. All patients underwent gastrograffin swallow on postoperative day 1. Patients were re-evaluated using the Eckhardt score on postoperative day 14.

Results

Ten patients underwent POEM. Seven patients had previous endoscopic treatments: 6 had balloon dilatation and 1 had botulinum toxin injection. Mean preoperative Eckhardt score was 8.1 ± 2.4. Mean preoperative lower esophageal sphincter resting and residual pressure was 32.3 ± 9.2 and 20.8 ± 5.3, respectively. Mean duration of surgery was 141.3 ± 43.7 minutes. Mean length of hospital stay was 1 day. No major perioperative complications occurred. On postoperative day 14, the mean Eckhardt score was 1 ± 1.2.

Conclusion

Our approach to POEM introduction was systematic and deliberate. The procedure is safe, feasible and has good perioperative outcomes. Our early results are consistent with current literature.  相似文献   
445.
In our previous study, the administration of oxytocin (OT) could precondition the heart against ischemia/reperfusion injury. In this study, to investigate the cardiac postconditioning effect of oxytocin, isolated rat hearts were mounted on a Langendorff perfusion apparatus. In all groups, the hearts underwent 30 min of regional ischemia followed by 120 min of reperfusion. In the ischemia/reperfusion (IR) group, ischemia and reperfusion was induced. In the ischemic postconditioning (Ipost) group, hearts underwent 6 cycles of 10s reperfusion and 10s ischemia at the beginning of reperfusion. In the other groups (III-IX), OT was perfused 5 min before the onset of reperfusion and continued for 25 min with following doses (Molar): 10(-12), 5 × 10(-12), 8 × 10(-12), 10(-11), 2 × 10(-11), 5 × 10(-11), and 10(-10). The infarct size and coronary effluent levels of creatine kinase-MB (CK-MB), lactate dehydrogenase (LDH) and malondialdehyde (MDA) were calculated at the end of reperfusion. The infarct size decreased considerably in Ipost group compared to IR group (P<0.05). Also, the infusion of oxytocin by doses of 8 × 10(-12)M, 10(-11)M and 2 × 10(-11)M dose-dependently reduced infarct size (P<0.05) significantly compared to the IR group. LDH level in coronary effluent was markedly decreased in Ipost group and treatment with oxytocin by doses of 8 × 10(-12)M, 10(-11)M, 2 × 10(-11)M and 5 × 10(-11)M (P<0.05) compared to IR group. Ipost, OT 2 × 10(-11)and 10(-11)M significantly decreased CK-MB level (P<0.05). Ipost, OT 8 × 10(-12), 10(-11) and 2 × 10(-11)M significantly decreased MDA level as compared to IR group. Our study shows that oxytocin dose-dependently exerts cardiac postconditioning.  相似文献   
446.
Exposure to visible light and near infrared (NIR) radiation in the wavelength region of 380 to 1400 nm may cause thermal retinal injury. In this analysis, the effective spectral radiance of a hot source is replaced by its temperature in the exposure limit values in the region of 380–1400 nm. This article describes the development and implementation of a computer code to predict those temperatures, corresponding to the exposure limits proposed by the American Conference of Governmental Industrial Hygienists (ACGIH®). Viewing duration and apparent diameter of the source were inputs for the computer code. At the first stage, an infinite series was created for calculation of spectral radiance by integration with Plancks law. At the second stage for calculation of effective spectral radiance, the initial terms of this infinite series were selected and integration was performed by multiplying these terms by a weighting factor R(λ) in the wavelength region 380–1400 nm. At the third stage, using a computer code, the source temperature that can emit the same effective spectral radiance was found. As a result, based only on measuring the source temperature and accounting for the exposure time and the apparent diameter of the source, it is possible to decide whether the exposure to visible and NIR in any 8-hr workday is permissible. The substitution of source temperature for effective spectral radiance provides a convenient way to evaluate exposure to visible light and NIR.  相似文献   
447.
448.
Primary central nervous system lymphoma (PCNSL) is a rare form of non‐Hodgkin lymphoma. In this report, we present 11 cases of PCNSL which were treated with high‐dose MTX and WBI with a localized radiation boost to the tumor bed.  相似文献   
449.
Objective. To assess the incidence and extent of cardiac involvement in systemic sclerosis (SSc) patients with no apparent cardiac symptoms. Methods. Surface electrocardiography, ambulatory electrocardiography, radionuclide ventriculography, myocardial scintigraphy, and echocardiography were performed in 18 patients. Results. These studies demonstrated ventricular tachycardia in 1 patient, nonsustained ventricular tachycardia in 5, supraventricular tachycardia in 6, decreased left ventricular ejection fraction in 2, decreased right ventricular ejection fraction in 8, and stress-induced reversible myocardial perfusion abnormalities in 6. Conclusion. These observations demonstrate a high rate of cardiac abnormalities in SSc patients without cardiac symptoms.  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