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   521篇
  免费   17篇
  国内免费   15篇
耳鼻咽喉   2篇
妇产科学   1篇
基础医学   45篇
临床医学   58篇
内科学   298篇
神经病学   17篇
特种医学   3篇
外科学   30篇
综合类   54篇
预防医学   9篇
药学   29篇
中国医学   7篇
  2023年   4篇
  2022年   15篇
  2021年   27篇
  2020年   24篇
  2019年   23篇
  2018年   57篇
  2017年   40篇
  2016年   25篇
  2015年   27篇
  2014年   55篇
  2013年   40篇
  2012年   28篇
  2011年   18篇
  2010年   17篇
  2009年   19篇
  2008年   19篇
  2007年   19篇
  2006年   18篇
  2005年   15篇
  2004年   8篇
  2003年   14篇
  2002年   7篇
  2001年   2篇
  2000年   1篇
  1999年   4篇
  1998年   3篇
  1997年   3篇
  1995年   2篇
  1994年   1篇
  1993年   2篇
  1992年   1篇
  1991年   1篇
  1989年   1篇
  1987年   1篇
  1986年   2篇
  1985年   2篇
  1984年   1篇
  1980年   1篇
  1978年   1篇
  1976年   1篇
  1975年   1篇
  1973年   2篇
  1971年   1篇
排序方式: 共有553条查询结果,搜索用时 15 毫秒
1.
2.
目的了解温州口岸出入境人员中的心房颤动的发生情况,探讨旅行保健方法。方法对检出的48例心房颤动患者的资料进行分析。结果对2003.11-2004.10从温州口岸出入境的19862名人员进行心电图检查,发现心房颤动病例48例,检出率为0.24%,其中男性29例,女性19例,男女之间检出率没有显著差异。心房颤动多见于老年人。结论出入境人员进行健康体检具有重要意义。确保出入境人员的健康。  相似文献   
3.
A 37-year-old Italian male developed a myocardial infarct with subsequent ventricular fibrillation. He was defibrillated seven times with up to 360 Joules. Thirteen days later the patient died of recurrent myocardial infarct due to thrombotic occlusion of the left circumflex coronary artery. At autopsy, necrosis of the right pectoralis muscle was observed. Electroporation is the pathogenetic mechanism of skeletal muscle damage due to multiple defibrillations with high energy levels. Received: 8 January 1998 Accepted: 15 April 1998  相似文献   
4.
地尔硫卓联合地高辛治疗心力衰竭并慢性快速房颤分析   总被引:3,自引:1,他引:2  
目的观察地尔硫卓联合小剂量地高辛对心力衰竭并慢性快速房颤患者血压、心室率和心功能的影响。方法 :心功能Ⅱ~Ⅲ级慢性房颤患者 10 6例 ,随机分为二组 ,对照组 5 0例 ,单用地高辛 ,治疗组 5 6例 ,地尔硫卓与地高辛联用 ,其余治疗二组相同 ,7~ 10d为一疗程 ,观察治疗前后血压、心率、左室射血分数 (LVEF)、心输出量 (CO)。结果 :治疗组较对照组心室率明显下降 ,控制满意 ,血压、LVEF及CO变化二组相似。结论 :地尔硫卓联合小剂量地高辛治疗心衰并慢性快速房颤患者心室率较单用地高辛效果更好 ,且较为安全。  相似文献   
5.
An increased incidence of sudden death has been reported in chronic alcoholism. To assess electrical vulnerability of the heart, action potential responses, and the role of the sympathetic system, a well-nourished canine model has been studied intact under chloralose anesthesia after 1 year of ethanol consumption at 36% of caloric intake. Two alcoholic groups were compared with controls (Group 1). In Group 2 myocardial vulnerability was assessed after chronic EtOH and superimposed acute administration. In Group 3 basal vulnerability was related to circulating norepinephrine and release of neurohormone from the myocardium. Subsequently the responsiveness to catecholamine infusion was determined. To assess vulnerability an electrode catheter was placed in the right ventricular apex. The basal ventricular fibrillation threshold (VFT) was reduced to 27 +/- 3 ma in Group 2 versus 43 +/- 1.0 in Group 1. Acute infusion of ethanol in Group 2 further reduced the threshold. Group 3 had a reduced basal VFT. Baseline arterial plasma levels of norepinephrine were 8-fold higher and coronary venous levels 13 times higher in the alcoholic group than in Group 1. However, VFT was not responsive to infused epinephrine, compared with Group 1 controls. In vitro study of superfused ventricular tissue from Group 3 revealed that basal action potential amplitude, overshoot, and resting potential were comparable with normals. Basal repolarization time (90%) was 198 +/- 12 msec in Group 3 versus 215 +/- 6 msec in Group 1 (p less than 0.05). After acute EtOH, repolarization time was shortened to 170 +/- 8.6 in Group 1 at 90 mg% ethanol (p less than 0.002), with minimal further change up to 280 mg%.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
Objective:To assess the sensitivity and the specifity of predicting idiopathic AF with P wave dura-tion and P wave dispersion. Methods: The maximum P wave duration and P wave dispersion in 36 patients with idio-pathic AF were measured and compared with those of sex-and age-matched healthy subjects. Results:The maxi-mum P wave duration and P wave dispersion were higher in patients with idiopathic Af than in control group. Themaximum P wave duration >110ms or P wave dispersion >40ms was used to differentiate patients from healthy  相似文献   
7.
Cardiac stimulation thresholds of short-duration large-amplitude electrical transients were studied. An isolated rabbit heart model was used and transients were applied directly to the heart through electrodes of 1 mm2 and 1 cm2 surface area. A variety of oscillatory waveforms and pulse configurations were studied and indicated that, for transients shorter than 100 μs, stimulation thresholds approach a constant charge-transfer density of 3·4 μC cm−2.  相似文献   
8.
IntroductionAtrial fibrillation (AF) is the most common arrhythmia and is associated with significant morbidity and mortality. The impact of matrix metalloproteinases (MMPs) on structural atrial remodeling and sustainment of AF in patients with persistent and permanent AF is unresolved.ObjectivesThe aim was to evaluate MMP-9 and its tissue inhibitor-1 (TIMP-1) as markers of atrial remodeling in patients with persistent AF (PAF) who underwent electrical cardioversion (ECV) and in patients with permanent AF (continuous AF, CAF).Patients and methodsPlasma levels of MMP-9 and TIMP-1, clinical findings, and echocardiographic parameters were evaluated in 39 patients with AF and in 14 controls with sinus rhythm.ResultsThe concentrations of MMP-9 were significantly higher in patients with PAF and CAF compared to controls. There was a significant increase of MMP-9 after ECV in the persistent AF group. The values of TIMP-1 were not significantly different between the groups. In patients with AF, MMP-9 levels were positively related to posterior wall thickness of the LV (r = 0.356, P = 0.049) and body mass index (r = 0.367, P = 0.046).ConclusionElevated levels of MMP-9 were related to the occurrence and maintenance of AF. This suggests that MMP-9 can be a marker of atrial remodeling in patients with AF. Regulation of the extracellular collagen matrix might be a potential therapeutic target in AF.  相似文献   
9.
10.
目的 探讨收缩压波动对房颤伴高血压患者预后的预测意义 方法 选取2012-2014年于新疆维吾尔自治区人民医院确诊为心房颤动伴高血压的患者,随访其收缩压的变化及平均收缩压,并监测其心源性死亡、急性冠脉综合征、慢性心力衰竭、脑栓塞及外周血管栓塞的发生率。结果在随访的过程中,随着收缩压波动幅度的增加,其终点事件发生率也在不断的增加,收缩压波动最大的四分位组主要终点事件及次要终点事件的发生率是要明显高于收缩压波动最小的四分位组,且患者随诊次数越多,收缩压波动对房颤患者预后的预测意义就越大,这种预测意义在平均收缩压较高的患者中更为明显。结论 收缩压波动可影响房颤伴高血压患者的预后,且收缩压波动越大,房颤患者的预后越不佳。  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