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121.
Long-term durability of open abdominal aortic aneurysm repair   总被引:10,自引:0,他引:10  
OBJECTIVE: In multiple comparisons of open vs endovascular (EVAR) repair of abdominal aortic aneurysms, the prior assumption that open repair produced superior durability has been challenged by advocates of EVAR. Although focus on EVAR reintervention has been intense, few contemporary studies document late outcomes after open repair; this was the goal of this study. METHODS: From January 1994 to December 1998 (chosen to ensure a minimum 5-year follow-up), 540 patients underwent elective open repair. Surveillance imaging (computed tomographic and magnetic resonance imaging scans) was obtained for 152 (57%) of the 269 patients who remained alive at a mean follow-up of 87 months. Study end points included freedom from graft-related interventions and aneurysm-related and overall survival (Kaplan-Meier test); factors predictive of these end points were determined by multivariate analysis. RESULTS: The mean age at operation was 73 years. A total of 76% of patients were male; 11% had renal insufficiency (creatinine > or =1.5 mg/dL), and 13% had chronic obstructive pulmonary disease. The aortic cross-clamp position was suprarenal in 135 (25%) patients, and 284 (53%) of patients had bifurcated grafts placed. Operative mortality (30 days) was 3%, and the median length of hospital stay was 7 days. Postoperative complications occurred in 68 (13%) patients. Predictors of postoperative complications included a history of myocardial infarction (hazard ratio [HR], 2.0; P = .01) and renal insufficiency (HR, 2.5; P = .02). The mean follow-up for all patients was 87 months. Actuarial survival was 70.7% +/- 2% and 44.3% +/- 2.4% at 5 and 10 years, respectively. Negative predictors of long-term survival included advanced age (HR, 1.1; P < .001), history of myocardial infarction (HR, 1.37; P = .02), and renal insufficiency (HR, 1.5; P = .04). Freedom from graft-related reintervention was 98.2% +/- 0.8% and 94.3% +/- 3.4% at 5 and 10 years, respectively. There were 13 late graft-related complications in 11 (2%) patients (mean follow-up, 7.2 years). Findings included seven anastomotic pseudoaneurysms (five were repaired), four graft limb occlusions, and two graft infections. Aneurysms were identified in noncontiguous arterial segments in 68 (45%) of 152 patients, most of which involved the iliac arteries and required no treatment because of small size. Late aortic aneurysms proximal to the repair were identified in 24% of patients, and 29 (19%) patients had multiple late synchronous aneurysms. CONCLUSIONS: Open repair remains a safe and durable option for the management of abdominal aortic aneurysms, with an excellent associated 10-year survival in patients who undergo operation at 75 years of age or younger. In addition, the freedom from graft-related reintervention is superior to that of EVAR. Finally, continued surveillance after open repair is appropriate and should be directed toward the detection of other aneurysms.  相似文献   
122.
Cardiovascular computed tomography (CCT) is a well-validated non-invasive imaging tool with an ever-expanding array of applications beyond the assessment of coronary artery disease. These include the evaluation of structural heart diseases, congenital heart diseases, peri-procedural electrophysiology applications, and the functional evaluation of ischemia. This breadth requires a robust and diverse training curriculum to ensure graduates of CCT training programs meet minimum competency standards for independent CCT interpretation. This statement from the Society of Cardiovascular Computed Tomography aims to supplement existing societal training guidelines by providing a curriculum and competency framework to inform the development of a comprehensive, integrated training experience for cardiology and radiology trainees in CCT.  相似文献   
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Background

We sought to evaluate the effect of application of the revised 2010 Task Force Criteria (TFC) on the prevalence of major and minor Cardiovascular Magnetic Resonance (CMR) criteria for Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) versus application of the original 1994 TFC. We also assessed the utility of MRI to identify alternative diagnoses for patients referred for ARVC evaluation.

Methods

968 consecutive patients referred to our institution for CMR with clinical suspicion of ARVC from 1995 to 2010, were evaluated for the presence of major and minor CMR criteria per the 1994 and 2010 ARVC TFC. CMR criteria included right ventricle (RV) dilatation, reduced RV ejection fraction, RV aneurysm, or regional RV wall motion abnormalities. When quantitative measures of RV size and function were not available, and in whom abnormal size or function was reported, a repeat quantitative analysis by 2 qualified CMR physicians in consensus.

Results

Of 968 patients, 220 (22.7%) fulfilled either a major or a minor 1994 TFC, and 25 (2.6%) fulfilled any of the 2010 TFC criterion. Among patients meeting any 1994 criteria, only 25 (11.4%) met at least one 2010 criterion. All patients who fulfilled a 2010 criteria also satisfied at least one 1994 criterion. Per the 2010 TFC, 21 (2.2%) patients met major criteria and 4 (0.4%) patients fulfilled at least one minor criterion. Eight patients meeting 1994 minor criteria were reclassified as satisfying 2010 major criteria, while 4 patients fulfilling 1994 major criteria were reclassified to only minor or no criteria under the 2010 TFC.Eighty-nine (9.2%) patients had alternative cardiac diagnoses, including 43 (4.4%) with clinically significant potential ARVC mimics. These included cardiac sarcoidosis, RV volume overload conditions, and other cardiomyopathies.

Conclusions

Application of the 2010 TFC resulted in reduction of total patients meeting any diagnostic CMR criteria for ARVC from 22.7% to 2.6% versus the 1994 TFC. CMR identified alternative cardiac diagnoses in 9.2% of patients, and 4.4% of the diagnoses were potential mimics of ARVC.  相似文献   
125.
Recent technologic advances in cardiac magnetic resonance (MR) imaging have resulted in images with high spatial and temporal resolution and excellent myocardial tissue characterization. Cardiac MR is a valuable imaging technique for detection and assessment of the morphology and functional characteristics of the nonischemic cardiomyopathy. It has gained acceptance as a standalone imaging modality that can provide further information beyond the capabilities of traditional modalities such as echocardiography and angiography. Black-blood fast spin-echo MR images allow morphologic assessment of the heart with high spatial resolution, while T2-weighted MR images can depict acute myocardial edema. Contrast material-enhanced images can depict and be used to quantify myocardial edema, infiltration, and fibrosis. This review presents recommended cardiac MR protocols for and the spectrum of imaging appearances of the nonischemic cardiomyopathies.  相似文献   
126.
PurposeWe aimed to assess the temporal change in radiation doses from coronary computed tomography angiography (CCTA) during a 6-year period. High CCTA radiation doses have been reduced by multiple technologies that, if used appropriately, can decrease exposures significantly.MethodsA total of 1277 examinations performed from 2005 to 2010 were included. Univariate and multivariable regression analysis of patient- and scan-related variables was performed with estimated radiation dose as the main outcome measure.ResultsMedian doses decreased by 74.8% (P < .001), from 13.1 millisieverts (mSv) (interquartile range 9.3-14.7) in period 1 to 3.3 mSv (1.8-6.7) in period 4. Factors associated with greatest dose reductions (P < .001) were all most frequently applied in period 4: axial-sequential acquisition (univariate: ?8.0 mSv [?9.7 to ?7.9]), high-pitch helical acquisition (univariate: ?8.8 mSv [?9.3 to ?7.9]), reduced tube voltage (100 vs 120 kV) (univariate: ?6.4 mSv [?7.4 to ?5.4]), and use of automatic exposure control (univariate: ?5.3 mSv [?6.2 to ?4.4]).ConclusionsCCTA radiation doses were reduced 74.8% through increasing use of dose-saving measures and evolving scanner technology.  相似文献   
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128.
Adult congenital heart disease patients present a unique challenge to the cardiac imager. Patients may present with both acute and chronic manifestations of their complex congenital heart disease and also require surveillance for sequelae of their medical and surgical interventions. Multimodality imaging is often required to clarify their anatomy and physiology. Radiation dose is of particular concern in these patients with lifelong imaging needs for their chronic disease. The second‐generation dual‐source scanner is a recently available advanced clinical cardiac computed tomography (CT) scanner. It offers a combination of the high‐spatial resolution of modern CT, the high‐temporal resolution of dual‐source technology, and the wide z‐axis coverage of modern cone‐beam geometry CT scanners. These advances in technology allow novel protocols that markedly reduce scan time, significantly reduce radiation exposure, and expand the physiologic imaging capabilities of cardiac CT. We present a case series of complicated adult congenital heart disease patients imaged by the second‐generation dual‐source CT scanner with extremely low‐radiation doses and excellent image quality.  相似文献   
129.
With the increasing use of coronary computed tomography angiography (CCTA) as a noninvasive tool to evaluate for coronary artery disease, physicians who request, perform, or interpret these studies should be aware of the associated potential risks of ionizing radiation. This article provides an overview of radiation issues in CT, the risks of diagnostic-level ionizing radiation, and strategies that can be adopted to minimize exposure to radiation of patients undergoing CCTA.  相似文献   
130.
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