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   319篇
  免费   32篇
  国内免费   5篇
儿科学   4篇
基础医学   12篇
口腔科学   1篇
临床医学   14篇
内科学   112篇
皮肤病学   22篇
神经病学   5篇
特种医学   21篇
外科学   23篇
综合类   25篇
预防医学   7篇
眼科学   1篇
药学   12篇
中国医学   3篇
肿瘤学   94篇
  2023年   5篇
  2022年   5篇
  2021年   11篇
  2020年   17篇
  2019年   11篇
  2018年   9篇
  2017年   11篇
  2016年   4篇
  2015年   16篇
  2014年   24篇
  2013年   39篇
  2012年   21篇
  2011年   26篇
  2010年   16篇
  2009年   17篇
  2008年   18篇
  2007年   18篇
  2006年   10篇
  2005年   7篇
  2004年   5篇
  2003年   4篇
  2002年   7篇
  2001年   12篇
  2000年   8篇
  1999年   2篇
  1998年   3篇
  1997年   4篇
  1996年   2篇
  1995年   4篇
  1994年   3篇
  1993年   1篇
  1992年   1篇
  1991年   2篇
  1988年   3篇
  1987年   1篇
  1985年   2篇
  1983年   1篇
  1982年   3篇
  1981年   2篇
  1977年   1篇
排序方式: 共有356条查询结果,搜索用时 15 毫秒
1.
Objective To evaluate the feasibility of mdiofrequency catheter ablation of atrial fibrilla-tion (AF) guided by complex fractionated atrial electrograms (CFAEs). Methods Twenty-two patients with drug refractory and symptomatic AF(16 paroxysmal, 6 persisten) were enrolled. Using Carto, the left atrial or biatrial replica was created during spontaneous or induced AF, and areas associated with CFAEs were identi-fied. Radiofrequency ablation at the site with CFAEs was performed and the end points were to eliminate CFAEs or convert to sinus rhythm. Results Thirteen patients(59%)were converted to sinus rhythm, (7 cases conver-ted directly to sinus rhythm, and 6 via the intermediate atrial tachycardia(AT) or atrial flutter (AFL). The re-maining nine patients required cardioversion with D. C. shock or drug. Repeat ablation was performed in 6 pa-tients (5 AT/AFL, 1 paroxysmal AF). During(10.9 ±4.8) months follow-up, 16 patients (73%) were free of arrhythmia and symptoms. CFAEs were most commonly found along the left interatrial septum, pulmonary veins, left atrial roof. CFAEs ablation prolonged AFCL[(157 ± 18) ms vs (211 ± 32) ms, P < 0.05]. Only one patient had pericardial tamponade that required pericardiocentesis. Conclusion Radiofrequeney catheter abla-tion of atrial fibrillation (AF) guided by CFAEs is safe and effective.  相似文献   
2.
3.
ObjectiveTo examine variation in trajectories of abandoning conventionally fractionated whole‐breast irradiation (CF‐WBI) for adjuvant breast radiotherapy among physician peer groups and the associated cost implications.Data SourcesMedicare claims data were obtained from the Chronic Conditions Data Warehouse for fee‐for‐service beneficiaries with breast cancer in 2011‐2014.Study DesignWe used social network methods to identify peer groups of physicians that shared patients. For each physician peer group in each time period (T1 = 2011‐2012 and T2 = 2013‐2014), we calculated a risk‐adjusted rate of CF‐WBI use among eligible women, after adjusting for patient clinical characteristics. We applied a latent class growth analysis to these risk‐adjusted rates to identify distinct trajectories of CF‐WBI use among physician peer groups. We further estimated potential savings to the Medicare program by accelerating abandonment of CF‐WBI in T2 using a simulation model.Data Collection/Extraction MethodsUse of conventionally fractionated whole‐breast irradiation was determined from Medicare claims among women ≥ 66 years of age who underwent adjuvant radiotherapy after breast conserving surgery.Principal FindingsAmong 215 physician peer groups caring for 16 988 patients, there were four distinct trajectories of abandoning CF‐WBI: (a) persistent high use (mean risk‐adjusted utilization rate: T1 = 94.3%, T2 = 90.6%); (b) decreased high use (T1 = 81.3%, T2 = 65.3%); (c) decreased medium use (T1 = 60.1%, T2 = 44.0%); and (d) decreased low use (T1 = 31.6%, T2 = 23.6%). Peer groups with a smaller proportion of patients treated at free‐standing radiation facilities and a larger proportion of physicians that were surgeons tended to follow trajectories with lower use of CF‐WBI. If all physician peer groups had practice patterns in T2 similar to those in the “decreased low use” trajectory, the Medicare program could save $83.3 million (95% confidence interval: $58.5 million‐$112.2 million).ConclusionsPhysician peer groups had distinct trajectories of abandoning CF‐WBI. Physician composition and setting of radiotherapy were associated with the different trajectories. Distinct practice patterns across the trajectories had important cost implications.  相似文献   
4.
ffeSUm Objectif Evalue lfefft de l'irrndintion hyethectionnd accdldrd (AHF) et de I'irrndiationhectionnd conventionnelle (CFI) dens le traitement du cancer PUlmonaire locaIid avanCd aax cellules nonpe-tites (M). ANM ta mawt du groupe Mforent irrndids dens un volume cibIe au chamP largeavec une hection winallere de 2Gy et dens un volume cible au petit chamP avec une hection jOurnaIiere de1Gy avec un intermlle Plus de 6h. In doSe totale du vOume cible au chamP large etait de 50Gy/2W/…  相似文献   
5.
6.
Overall, 133 patients underwent 170 procedures for the treatment of persistent ATa following an index cryoballoon pulmonary vein isolation (n = 715). After all the procedures, > 90% of the patients had a roof line, a mitral isthmus and/or septal line, and a cavotricuspid isthmus line. Ninety-two patients (69.2%) were in sinus rhythm after a median of 36 months since the index cryoballoon PVI. ATa: atrial tachyarrhythmia; cryo: cryoballoon; CTI: cavotricuspid isthmus; LSPV: left superior pulmonary vein; LIPV: left inferior pulmonary vein; PVI: pulmonary vein isolation; RF: radiofrequency; RSPV: right superior pulmonary vein; RIPV: right inferior pulmonary vein.
  相似文献   
7.
目的探讨阵发性和持续性心房颤动(简称房颤)患者肺静脉前庭(PVO)和左房(LA)内连续碎裂电位(CFEAs)的电生理特点。方法入选24例药物治疗无效的房颤患者,依房颤节律分为阵发性房颤(PAF)组与持续性房颤(PeAF)组,每组各12例,根据距离肺静脉口远近,将肺静脉分成距肺静脉5~10 mm(Ⅰ区)与10~20 mm(Ⅱ区)两区。在房颤时,应用EnSite NavX标测系统高密度标测PVO和LA,比较两组平均CFE值(碎裂间期)≤70ms的CFAEs的电生理特点。结果①PeAF组LA内径大于PAF组(P<0.05),PAF组LA后壁CFAES分布比例最低,顶部最高,PeAF组前后壁最低,左心耳最高;PAF组PVO较LA高(P<0.05),PeAF组PVO和LA无差异。②两组间总PVO区域连续CFAEs比例无差异,PeAF组LA明显高于PAF组(P<0.05),PAF左下PVO连续CFAEs分布比例高于PeAF(P=0.02),另三支PVO无明显差别。除顶部PAF组连续CFAEs分布高于PeAF组(P=0.02)外,PeAF组下壁、左心耳及二尖瓣环均显著高于PAF组(P均<0.001)。③PAF组各支Ⅰ区连续CFAEs分布高于Ⅱ区(P<0.05),PeAF组左下PVOⅠ区高于Ⅱ区(P<0.05),右上PVOⅡ区高于Ⅰ区(P<0.05),另两支PVO无差异。④PAF组PVO平均CFE明显低于LA(P<0.0001),PeAF组两区域及两组间PVO则无差异;PeAF组LA平均CFE值较低,连续CFAEs数量较多,房颤周长较短。结论 LA电解剖重构在房颤维持中起重要作用,PeAF LA内连续CFAEs分布较PAF广泛,碎裂程度更高,房颤周长较短。PVO绝大多数连续CFAEs位于5~10 mm区域。  相似文献   
8.
Cerebral Microthromboembolism After CFAE Ablation . Background: The incidence of cerebral thromboembolism after pulmonary vein isolation (PVI) ranges from 2% to 14%. This study investigated the incidence of cerebral thromboembolism after complex fractionated atrial electrogram (CFAE) ablation with or without PVI. Methods: One hundred consecutive atrial fibrillation (AF) patients (50 paroxysmal and 50 persistent, including 10 longstanding) who underwent CFAE ablation combined with (n = 41, PVI+CFAE group) or without (n = 59, CFAE group) PVI were studied. Coronary angiography (CAG) was conducted with AF ablation in 5 cases in which coronary artery stenosis was suspected on 3D‐computed tomography. PVI was performed before CFAE ablation without circular catheter during AF. After termination of AF, additional ablation was performed to complete PVI with a circular catheter. All patients underwent cerebral magnetic resonance imaging (MRI) including diffusion‐weighted MRI and T2‐weighted MRI the day after ablation. Results: New thromboembolism was detected in 7.0%, and there was no significant difference between the 2 strategies (7.3% in PVI+CFAE group, 6.8% in CFAE group). CHADS2 score (1.6 ± 1.0 vs 0.8 ± 0.9, P < 0.05), left atrial volume (LAV; 83.8 ± 27.1 vs 67.8 ± 21.8, P < 0.05), and left ventricular ejection fraction (LVEF, 53.1 ± 9.2 vs 65.1 ± 9.7, P < 0.01) were significantly different when comparing patients with or without thromboembolism. In multivariate analysis, LVEF (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.84–0.99; P < 0.05) and concomitant CAG (OR 18.82; 95% CI, 1.77–200.00; P < 0.05) were important predictors of new cerebral thromboembolism. Conclusions: The incidence of cerebral microthromboembolism after CFAE ablation was not greater than previous reports in PVI. Cautious management is required during AF ablation, especially in the patients with low LVEF. (J Cardiovasc Electrophysiol, Vol. 23, pp. 567–573, June 2012)  相似文献   
9.
Atrial fibrillation (AF) ablation has evolved to the treatment of choice for patients with drug-resistant and symptomatic AF. Pulmonary vein isolation at the ostial or antral level usually is sufficient for treatment of true paroxysmal AF. For persistent AF ablation, drivers and perpetuators outside of the pulmonary veins are responsible for AF maintenance and have to be targeted to achieve satisfying arrhythmia-free success rate. Both complex fractionated atrial electrogram (CFAE) ablation and linear ablation are added to pulmonary vein isolation for persistent AF ablation. Nevertheless, ablation failure and necessity of repeat ablations are still frequent, especially after persistent AF ablation. Pulmonary vein reconduction is the main reason for arrhythmia recurrence after paroxysmal and to a lesser extent after persistent AF ablation. Failure of persistent AF ablation mostly is a consequence of inadequate trigger ablation, substrate modification or incompletely ablated or reconducting linear lesions. In this review we will discuss these points responsible for AF recurrence after ablation and review current possibilities on how to overcome these limitations.  相似文献   
10.
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