全文获取类型
收费全文 | 16761篇 |
免费 | 1521篇 |
国内免费 | 404篇 |
专业分类
耳鼻咽喉 | 31篇 |
儿科学 | 220篇 |
妇产科学 | 87篇 |
基础医学 | 627篇 |
口腔科学 | 22篇 |
临床医学 | 3597篇 |
内科学 | 8747篇 |
皮肤病学 | 51篇 |
神经病学 | 590篇 |
特种医学 | 294篇 |
外科学 | 889篇 |
综合类 | 1795篇 |
预防医学 | 246篇 |
眼科学 | 37篇 |
药学 | 1102篇 |
7篇 | |
中国医学 | 173篇 |
肿瘤学 | 171篇 |
出版年
2024年 | 30篇 |
2023年 | 405篇 |
2022年 | 482篇 |
2021年 | 851篇 |
2020年 | 839篇 |
2019年 | 867篇 |
2018年 | 713篇 |
2017年 | 583篇 |
2016年 | 564篇 |
2015年 | 557篇 |
2014年 | 1084篇 |
2013年 | 1124篇 |
2012年 | 778篇 |
2011年 | 796篇 |
2010年 | 655篇 |
2009年 | 693篇 |
2008年 | 750篇 |
2007年 | 740篇 |
2006年 | 605篇 |
2005年 | 628篇 |
2004年 | 537篇 |
2003年 | 588篇 |
2002年 | 433篇 |
2001年 | 403篇 |
2000年 | 336篇 |
1999年 | 297篇 |
1998年 | 300篇 |
1997年 | 242篇 |
1996年 | 210篇 |
1995年 | 182篇 |
1994年 | 152篇 |
1993年 | 161篇 |
1992年 | 156篇 |
1991年 | 128篇 |
1990年 | 143篇 |
1989年 | 107篇 |
1988年 | 105篇 |
1987年 | 78篇 |
1986年 | 64篇 |
1985年 | 62篇 |
1984年 | 50篇 |
1983年 | 46篇 |
1982年 | 37篇 |
1981年 | 22篇 |
1980年 | 28篇 |
1979年 | 22篇 |
1978年 | 22篇 |
1977年 | 15篇 |
1976年 | 6篇 |
1972年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
《The Journal of thoracic and cardiovascular surgery》2023,165(1):94-103.e24
ObjectiveNew-onset postoperative atrial fibrillation (POAF) after cardiac surgery is common, with rates up to 60%. POAF has been associated with early and late stroke, but its association with other cardiovascular outcomes is less known. The objective was to perform a meta-analysis of the studies reporting the association of POAF with perioperative and long-term outcomes in patients with cardiac surgery.MethodsWe performed a systematic review and a meta-analysis of studies that presented outcomes for cardiac surgery on the basis of the presence or absence of POAF. MEDLINE, EMBASE, and the Cochrane Library were assessed; 57 studies (246,340 patients) were selected. Perioperative mortality was the primary outcome. Inverse variance method and random model were performed. Leave-one-out analysis, subgroup analyses, and metaregression were conducted.ResultsPOAF was associated with perioperative mortality (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.58-2.33), perioperative stroke (OR, 2.17; 95% CI, 1.90-2.49), perioperative myocardial infarction (OR, 1.28; 95% CI, 1.06-1.54), perioperative acute renal failure (OR, 2.74; 95% CI, 2.42-3.11), hospital (standardized mean difference, 0.80; 95% CI, 0.53-1.07) and intensive care unit stay (standardized mean difference, 0.55; 95% CI, 0.24-0.86), long-term mortality (incidence rate ratio [IRR], 1.54; 95% CI, 1.40-1.69), long-term stroke (IRR, 1.33; 95% CI, 1.21-1.46), and longstanding persistent atrial fibrillation (IRR, 4.73; 95% CI, 3.36-6.66).ConclusionsThe results suggest that POAF after cardiac surgery is associated with an increased occurrence of most short- and long-term cardiovascular adverse events. However, the causality of this association remains to be established. 相似文献
3.
Jeffrey J. Silbiger 《Echocardiography (Mount Kisco, N.Y.)》2019,36(5):954-957
Secondary tricuspid regurgitation (TR) caused by right ventricular enlargement in the setting of left heart disease/pulmonary hypertension has been well described. In contrast, that associated with right atrial enlargement—atrial functional TR (AF‐TR)—remains largely underappreciated. AF‐TR most often occurs in the setting of lone atrial fibrillation, although it is also seen in its absence (idiopathic AF‐TR). Several recent studies have found that the prevalence, hemodynamic significance, and prognosis of AF‐TR are not inconsequential, suggesting increased physician awareness of this novel clinical entity is warranted. This article discusses the pathogenesis, echocardiographic findings, and treatment of this underappreciated cause of secondary TR. 相似文献
4.
5.
6.
Sharada Sivaram Kalavakolanu 《Journal of the Saudi Heart Association》2015,27(3):206-209
We report a case of a young male presenting as Restrictive cardiomyopathy, refractory heart failure and syncope due to typical right atrial flutter complicating hypertrophic cardiomyopathy.Successful catheter ablation of the flutter promptly ameliorated the congestive failure with resolution of restrictive physiology. 相似文献
7.
Evaluation of Adult versus Pediatric Transesophageal Echocardiography Probe Efficiency for Guiding Septal Puncture during Atrial Fibrillation Ablation 下载免费PDF全文
8.
Provocation of Atrial Fibrillation Triggers During Ablation: Does the Use of General Anesthesia Affect Inducibility? 下载免费PDF全文
9.
《Journal of Cardiovascular Computed Tomography》2020,14(4):363-369
BackgroundData on left ventricular (LV) deformation imaging using CT angiography (CTA) are scarce and the feasibility of atrial deformation analysis by CT has not been addressed. We aimed to compare 2D echocardiographic and CT derived LV and left atrial (LA) global longitudinal strain (GLS) obtained by using a novel feature tracking algorithm in patients following transcatheter aortic valve implantation.MethodsTwenty-eight patients were included who underwent retrospectively-gated 256-slice CTA and speckle-tracking echocardiography (STE) on the same day. CT datasets in 10% increments were reconstructed throughout the cardiac cycle. LV GLS and LA global peak reservoir strain (LA GS) was measured.ResultsMedian absolute values for LV GLS were 19.9 [14.8–22.4] vs. 19.9 [16.8–24.7], as measured by CT vs STE, respectively (p = 0.017). We found good inter-modality correlation for LV GLS (ρ = 0.78, p < 0.05) with a mean bias of −1.6. Regarding atrial measurements, the median LA GS was 19.0 [13.5–27.3] for CT vs. 28.0 [17.5–32.6] for STE (p < 0.001) with a mean bias of −5.6 between CT and STE and a correlation coefficient of ρ = 0.87, p < 0.001. CT measurements were highly reproducible: intra-observer intra-class correlation coefficient was 0.96 for LV GLS and 0.95 for LA GS.ConclusionWe detected good correlation between CTA and echocardiography-based LV and LA longitudinal strain parameters. CTA provides accurate strain measurements with high reproducibility. Feature tracking-based deformation analysis could provide a clinically important addition to CT examinations by complementing anatomical information with functional data. 相似文献
10.
魏丽娟 《中国医疗器械信息》2020,(5):65-66
目的:应用经食管实时三维超声心动图(RT-3D-TEE)技术,探讨房性心律失常对二尖瓣结构和功能的影响.方法:选取2018年6月~2019年6月本院收治的房性心律失常拟行射频消融的患者49例纳入观察组,另外选取21例正常窦性心律者作为对照组,所有患者均行经胸超声心电图(TTE)和经食管实时三维超声心动图(RT-3D-TEE)检查,将两组患者的瓣环投影面积(A2D)、瓣环周长(C3D)、瓣环高度(H)、瓣环前后径(DAP)、瓣环前外侧至后内侧直径(DAIPm)、左室射血分数(LVEF)、左心房前后径(Lad)等参数进行比较,并分别计算对合面积和对合指数,之后采取二项Logistic回归分析或逐步线性回归对各参数及临床因素与对合指数的相关性进行分析.结果:两组患者在LVEF和对合面积方面的比较无明显差异(P>0.05),在A2D、C3D、H、DA、PDAIPm、Lad方面的比较,房性心律失常组患者明显高于正常窦性心律组患者(P<0.05),且观察组患者的对合指数明显降低(P<0.05).将49例观察组患者以不同心律失常类型分为持续性房颤、阵发性房颤、房扑、混合型房性心律失常4个亚组,采用单因素方差分析,发现在LVEF、C3D、Lad、对合指数方面的比较,各亚组间无明显差异(P>0.05).采用二项Logistic回归分析发现,女性是导致对合指数低的危险因素,另外对合指数较低、房性心律失常是导致二尖瓣返流的重要因素.结论:房性心律失常对患者二尖瓣的A2D、C3D、H、DA、PDAIPm、Lad等都会造成较大影响,从而降低对合指数,影响二尖瓣的正常功能,导致二尖瓣返流的发生. 相似文献