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   3137篇
  免费   226篇
  国内免费   10篇
耳鼻咽喉   27篇
儿科学   69篇
妇产科学   25篇
基础医学   497篇
口腔科学   22篇
临床医学   342篇
内科学   691篇
皮肤病学   69篇
神经病学   433篇
特种医学   122篇
外国民族医学   1篇
外科学   418篇
综合类   3篇
一般理论   5篇
预防医学   158篇
眼科学   66篇
药学   218篇
中国医学   5篇
肿瘤学   202篇
  2023年   20篇
  2022年   36篇
  2021年   112篇
  2020年   54篇
  2019年   100篇
  2018年   109篇
  2017年   64篇
  2016年   94篇
  2015年   113篇
  2014年   137篇
  2013年   174篇
  2012年   260篇
  2011年   278篇
  2010年   153篇
  2009年   120篇
  2008年   198篇
  2007年   194篇
  2006年   182篇
  2005年   177篇
  2004年   157篇
  2003年   142篇
  2002年   97篇
  2001年   34篇
  2000年   38篇
  1999年   34篇
  1998年   35篇
  1997年   31篇
  1996年   27篇
  1995年   18篇
  1994年   15篇
  1993年   19篇
  1992年   15篇
  1991年   16篇
  1990年   15篇
  1989年   12篇
  1988年   7篇
  1987年   10篇
  1985年   6篇
  1984年   7篇
  1983年   3篇
  1982年   8篇
  1981年   4篇
  1979年   6篇
  1978年   5篇
  1977年   3篇
  1976年   6篇
  1973年   4篇
  1972年   4篇
  1969年   3篇
  1933年   3篇
排序方式: 共有3373条查询结果,搜索用时 15 毫秒
101.
Antiplatelet agents have been extensively used in acute coronary syndromes and improve clinical outcome in STEMI patients. Previous experimental studies of the impact of antiplatelet agents on infarct size have been equivoqual. We questioned whether clopidogrel might reduce infarct size in STEMI patients, independently of any antithrombotic effect, by activating a post-conditioning-like myocardial protection. We retrospectively analyzed three recent controlled, randomized, proof of concept clinical trials aimed at determining whether PCI post-conditioning might attenuated infarct size in STEMI. We addressed whether clopidogrel (300-600?mg before angioplasty) might have influenced infarct size using a multivariable linear regression analysis with infarct size as the continuous outcome variable and age, clopidogrel and GP IIb/IIIa inhibitors, post-conditioning, area at risk, ischemia time, coronary thrombectomy and final TIMI flow, as covariates. In this population of 88 STEMI patients, ischemic post-conditioning and clopidogrel administration were the only two therapeutic independent predictors of the final infarct size as determined by cardiac enzymes release (p?=?0.005 and p?相似文献   
102.
This Phase 1/2 study aimed to determine optimal doses of daunorubicin (DNR; mg/m2) and cytarabine (mg/m2) to be combined with fractionated doses of gemtuzumab ozogamicin (GO, Mylotarg®; 3 mg/m2 on day 1, 4, and 7) satisfying safety requirements. Three dose levels of DNR/AraC were investigated namely (45, 100), (60, 100), and (60, 200). Patients included were acute myeloid leukemia in first relapse, aged 50–70 years. Hematological recovery was 31 days for neutrophil and 32 days for platelet counts. A documented infectious episode > Grade 2 occurred in 11/20 patients (55%). None of the 20 patients had signs of veno‐occlusive disease. Overall, eleven patients reached complete remission (CR), two CR with incomplete platelets recovery. The results showed that combination of fractionated GO doses with DNR at 60 mg/m2/d for 3 days and cytarabine at 200 mg/m2/d for 7 days is tolerable and could be further investigated in the front‐line therapy. Am. J. Hematol., 2012. © 2011 Wiley Periodicals, Inc.  相似文献   
103.
104.
ObjectiveThis study investigated the effects of a cervical spinal cord injury (SCI) on the modulation of cortical desynchronization (ERD) during isometric contractions at different force levels.MethodsFor 8 able-bodied (AB) and 6 cervical SCI participants, the net joint moment and electroencephalographic activities were recorded during isometric contractions of the right elbow in flexion and in extension at 3 force levels, that is, during intact and altered muscle contractions for SCI participants. The mean net moment and ~20 Hz ERD from C3 electroencephalographic electrode were compared between AB and SCI participants.ResultsIn flexion, that is, during intact contractions for all participants, the mean net moment and the ERD increased with the required force level. In extension, that is, during altered contractions, the mean net moment increased for 3 SCI participants while it was almost zero for 3 other SCI participants. The associated ERD increased with the required force level for all participants.ConclusionThe cortical desynchronization was modulated by the intent to modulate the force level rather than the actual modulation of the force production.SignificanceThese results provide a better understanding of the modulation of the cortical desynchronization following SCI. Potential applications could include the control of neuroprostheses.  相似文献   
105.
Brain abnormalities in Williams syndrome (WS) have been consistently reported, despite few studies have devoted attention to connectivity between different brain regions in WS. In this study, we evaluated corpus callosum (CC) morphometry: bending angle, length, thickness and curvature of CC using a new shape analysis method in a group of 17 individuals with WS matched with a typically developing group. We used this multimethod approach because we hypothesized that neurodevelopmental abnormalities might result in both volume changes and structure deformation. Overall, we found reduced absolute CC cross-sectional area and volume in WS (mean CC and subsections). In parallel, we observed group differences regarding CC shape and thickness. Specifically, CC of WS is morphologically different, characterized by a larger bending angle and being more curved in the posterior part. Moreover, although CC in WS is shorter, a larger relative thickness of CC was found in all callosal sections. Finally, groups differed regarding the association between CC measures, age, white matter volume and cognitive performance. In conclusions, abnormal patterns of CC morphology and shape may be implicated in WS cognitive and behavioural phenotype.  相似文献   
106.
107.
Single‐lumen cannula venovenous (VV) extracorporeal membrane oxygenation (ECMO) is a special extracorporeal life support (ECLS) technique used for neonatal and pediatric refractory hypoxemia. This is an alternative flow rate ECLS that consists of successive clamping on the drainage and the injection lines. Currently, the Armand‐Trousseau's pediatric intensive care unit remains the only pediatric ECMO center proposing this partial assistance. This article details a technical note and a retrospective analysis of our experience in refractory hypoxemia. The retrospective study, from 2007 to 2011, included all pediatric and neonatal patients treated by single‐lumen cannula VV ECMO. The study was focused on pre‐ECMO patient characteristics and complications during ECMO course. During the last 5 years, 67 pediatric patients were assisted by this single‐lumen cannula VV ECMO. Sixty‐one patients (91%) were newborns. Thirty‐nine patients presented with meconium aspiration syndrome (58%), which was the most frequent etiology. Before cannulation, mean oxygenation index (OI) was 32 ± 11, alveolar‐arterial oxygen difference was 604 ± 47 mm Hg, and partial pressure arterial oxygen/fraction inspired oxygen ratio was 59.2 ± 35.8. Forty‐eight patients (72%) presented pulmonary hypertension, and 66 patients were treated by nitric oxide (98%). Fifty patients (75%) were treated by vasopressors or inotropic drugs. Average duration of ECMO was 13.2 ± 7.8 days. There were forty‐six survivors (69%). The worst prognosis was for respiratory syncytial virus pneumonia. Complications like acute renal injury and hematologic and transfusion acts were not so different than those observed in classical ECMO techniques. Nevertheless, 19 patients presented a stroke (28% of the overall population), but this high rate did not seem to be due to the ECLS technique used. Single‐lumen cannula VV ECMO is a partial and efficient ECMO support. Our experience shows that this technique is as efficient and less invasive than two cannulas ECMO. The single‐lumen cannula VV ECMO is a simple and safe ECLS support used for neonatal or pediatric refractory hypoxemia. Because this is a partial assistance, it is a promising ECLS support.  相似文献   
108.
109.
110.

Purpose

Our objective was to develop and evaluate a Generic Integrated Objective Structured Assessment Tool (GIOSAT) to integrate Medical Expert and intrinsic (non-medical expert) CanMEDS competencies with non-technical skills for crisis simulation.

Methods

An assessment tool was designed and piloted using two pediatric anesthesia scenarios (laryngospasm and hyperkalemia). Following revision of the tool, we used previously recorded videos of anesthesia residents (n = 50) who managed one of two intraoperative advanced cardiac life support (ACLS) scenarios (ventricular tachycardia or ventricular fibrillation). Four independent trained raters, blinded to the residents’ level of training, analyzed the video recordings using the GIOSAT scale. Inter-rater reliability was calculated using intraclass correlations (ICCs) for single raters (single measure) and the average of the four raters (average measure), and construct validity was investigated by correlating GIOSAT scores with postgraduate year of residency (PGY).

Results

Total GIOSAT scores for the ACLS scenarios had single measure ICCs of 0.62 and average measure ICCs of 0.85. Inter-rater reliability was substantial for both Medical Expert and intrinsic competencies (single measure ICCs 0.69 and 0.62, respectively; average measure ICCs 0.90 and 0.82, respectively). We found significant correlations between PGY level and total GIOSAT score (r = 0.36; P = 0.011) and between PGY level and Medical Expert competencies (r = 0.42; P = 0.003); however, correlations were not found between PGY level and intrinsic CanMEDS competencies (r = 0.24; P = 0.09).

Conclusion

Inter-rater reliability of the total GIOSAT scores using four trained raters was substantial. Significant correlation between PGY and (i) total GIOSAT score and (ii) Medical Expert competencies supports construct validity. Evidence of validity was not obtained for intrinsic CanMEDS competencies.  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