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Background

The optimal noninvasive test (NIT) for patients with diabetes and stable symptoms of coronary artery disease (CAD) is unknown.

Objectives

The purpose of this study was to assess whether a diagnostic strategy based on coronary computed tomographic angiography (CTA) is superior to functional stress testing in reducing adverse cardiovascular (CV) outcomes (CV death or myocardial infarction [MI]) among symptomatic patients with diabetes.

Methods

PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) was a randomized trial evaluating an initial strategy of CTA versus functional testing in stable outpatients with symptoms suggestive of CAD. The study compared CV outcomes in patients with diabetes (n = 1,908 [21%]) and without diabetes (n = 7,058 [79%]) based on their randomization to CTA or functional testing.

Results

Patients with diabetes (vs. without) were similar in age (median 61 years vs. 60 years) and sex (female 54% vs. 52%) but had a greater burden of CV comorbidities. Patients with diabetes who underwent CTA had a lower risk of CV death/MI compared with functional stress testing (CTA: 1.1% [10 of 936] vs. stress testing: 2.6% [25 of 972]; adjusted hazard ratio: 0.38; 95% confidence interval: 0.18 to 0.79; p = 0.01). There was no significant difference in nondiabetic patients (CTA: 1.4% [50 of 3,564] vs. stress testing: 1.3% [45 of 3,494]; adjusted hazard ratio: 1.03; 95% confidence interval: 0.69 to 1.54; p = 0.887; interaction term for diabetes p value = 0.02).

Conclusions

In diabetic patients presenting with stable chest pain, a CTA strategy resulted in fewer adverse CV outcomes than a functional testing strategy. CTA may be considered as the initial diagnostic strategy in this subgroup. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550)  相似文献   
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颅颈畸形手术涉及复杂的解剖变异,手术风险高,操作难度大,传统的教学方式受制于抽象的讲解,学习者很难对颅颈畸形解剖,手术方案及过程有直观的认识。本研究将CTA三维重建导航和术中外视镜操作技术引入颅颈畸形手术教学实践中,术前通过CTA三维重建在导航仪软件上了解颅颈畸形变异情况,规划手术方案。术中采用外视镜操作,所有学生戴上3D眼镜观看手术。将无法直观显示的、抽象的解剖结构以三维立体图像对学生进行展示。使传统被动抽象的教学方式变成直观形象生动的学习方式。增强了神经外科临床专业研究生对颅颈畸形手术解剖认识,提高了手术操作的积极性,缩短了培养时间。  相似文献   
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The 15th Society of Cardiovascular Computed Tomography (SCCT) annual scientific meeting (ASM) welcomed 770 digital attendees from 44 countries, over 2 days, with a program that included 30 sessions across three simultaneously streaming channels, 10 exhibitors and a diverse range of scientific abstracts. In addition, #SCCT2020 generated >5900 tweets from nearly 700 engaged social media participants resulting in an estimated 38 million digital impressions and becoming #1 trending medical meeting in social media in the world during the meeting time period. This article summarizes the many themes and topics of presentation and discussion in this meeting, and the many technical advances that are likely to impact future clinical practice in cardiovascular computed tomography.  相似文献   
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目的 基于四维计算机X线断层扫描(Computed tomography,CT)血管成像(Dynamic four-dimensional CTA,4D-CTA)测量,计算颅内动脉瘤心动周期内膨胀率,探讨颅内动脉瘤破裂与膨胀率的相关性。方法 回顾性分析2018年5月-2020年5月就诊于哈尔滨医科大学附属第四医院微创神经外科一病区64例(其中未破裂动脉瘤24个,破裂动脉瘤40个)患者的完整资料; 所有患者均行4D-CTA扫描并重建图像; 依据动脉瘤破裂与否,患者分为未破裂组、破裂组; 将1个心动周期的图像数据分成20个阶段,判断动脉瘤是否存在异常搏动点; 同时记录和量化每个阶段动脉瘤的形态特征,计算其体积变化率(膨胀率); 分析动脉瘤破裂相关的危险因素。结果 未破裂组中男女患者比例差异不大; 破裂组女性患者则占70%,女性患者比例显著高于男性; 破裂组吸烟史的比例明显高于未破裂组; 破裂组瘤高(4.63±1.56)mm,瘤宽(4.72±3.68)mm,瘤颈宽(3.86±1.69)mm均大于未破裂组; 破裂组异常搏动点有29个(占72.5%)、膨胀率(14.56±6.25)%; 未破裂组异常搏动点13个(占54.2%)、膨胀率(10.21±3.26)%; 2组有明显差异(P<0.05)。此外,多因素Logistic回归分析显示动脉瘤破裂与吸烟史、纵横比、异常搏动点、膨胀率有关(P<0.05)。ROC分析中纵横比临界值为1.145(P=0.002),灵敏度为77.5%,特异性为58.3%; 存在异常搏动点与否的阈值为0.5(P=0.032),灵敏度为72.5%、特异性为45.8%; 膨胀率的临界值为9.775%(P=0.001),灵敏度为85.0%、特异性为54.2%。结论 借助4D-CTA能观察心动周期内颅内动脉瘤动态变化; 本研究成功量化了动脉瘤膨胀率,颅内动脉瘤破裂与膨胀率有关; 当膨胀率>9.775%,或纵横比>1.145,或存在异常搏动点时动脉瘤破裂风险将进一步增加。  相似文献   
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Background and purpose

Carotid webs are intraluminal filling defects at the carotid bulb which are considered rare, though possibly underappreciated entities with recent studies demonstrating a likely casual association with ischemic stroke. The purpose of the study is to describe our recent experience with clinical and imaging manifestations of carotid webs.

Materials and methods

A retrospective review of CTA neck studies in all adult patients presenting to our institution during the 19-month study interval was performed to determine the presence of carotid webs. Subsequent chart review of these patients with webs was performed to assess their clinical history and to obtain demographic detail.

Results

A total of 14 patients were identified with carotid webs in the study population. The mean age of patients with webs was 42.1?years (range: 28–54), consisting mostly of African Americans (86%) and females (64%). Ten (71%) of web patients had a history of ischemic stroke, each ipsilateral to the side of web, and at least four of these patients had recurrent ischemic stroke.

Conclusion

We provide one of the largest sample sizes of webs gathered in a single study. Given its association with ischemic stroke, carotid webs should be assessed for in all patients presenting with ischemic stroke, especially younger African Americans.  相似文献   
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BackgroundWhen patients with Fontan circulation require a computed tomographic pulmonary angiogram (CTPA), there are significant challenges in achieving adequate contrast opacification due to the altered anatomical connections. This study used Time Resolved Angiography with Interleaved Stochastic Trajectories (TWIST) Magnetic Resonance Angiography (MRA) to examine contrast circulation in a cohort of patients with Fontan circulation who were having routine MRI follow up to inform the contrast timing of any subsequent CT.MethodsThis is a single centre, cross-sectional, observational, retrospective study. The time to peak (TTP) signal intensity from the MRA was recorded using regions of interest on the aorta, pulmonary arteries, cavae and Fontan conduit. Patients were grouped by ejection fraction, global longitudinal strain, indexed stroke volume and cardiac index to examine if these cardiac performance parameters affected the mean TTP. Statistical analysis was performed to find the mean TTP for each of the vessels, which was consequently compared between the different cardiac performance parameters.Results35 patients were included in the study. Mean TTP contrast enhancement was 31s in the thoracic aorta, 46s in the right pulmonary artery, 41s in the left pulmonary artery and 55s in the Fontan conduit. Cardiac performance shows no statistically significant relationship to the peak contrast enhancement whether measured by ejection fraction, global longitudinal strain, stroke volume index or cardiac index.ConclusionThe mean optimal timing for a single-phase examination of the Fontan circulation, following an upper limb injection, was 55 s following start of contrast injection irrespective of cardiac performance. In TWIST MRA, the IV bolus is 4–5 s duration. A longer bolus is required for CTA, around 20s, suggesting an additional delay will be required. We propose that an optimal single phase CTPA to be protocolled at 70 s following the start of contrast injection, assuming adequate iodinated contrast dose.  相似文献   
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