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AIMS: Primary amyloidosis (AL) is a systemic disease; however, there is limited information regarding the presence and character of vascular abnormalities. METHODS AND RESULTS: Validated ultrasound techniques were used to prospectively determine carotid artery intimal-medial thickness (IMT) and brachial artery flow-mediated dilatation (FMD) in 59 consecutive AL patients and 17 age-similar, healthy, asymptomatic volunteers (CON). Carotid IMT was increased in AL when compared with CON (0.07 +/- 0.02 vs. 0.04 +/- 0.01 mm, P < 0.01). Similarly, brachial artery FMD was significantly lower in AL when compared with CON subjects (3 +/- 7 vs. 12 +/- 8%, P < 0.01). Multivariable analysis revealed that AL was associated with larger IMT and lower FMD after controlling for several confounding variables. However, within AL cases, there was not a significant association of cardiac vs. non-cardiac involvement with IMT or FMD (P = 0.1 and 0.2, respectively). CONCLUSION: AL is associated with abnormal vascular morphology and endothelial dysfunction. Vascular abnormalities do not appear to be related to echocardiographic evidence of cardiac involvement.  相似文献   
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OBJECTIVES: The objective of this study was to examine the relationship between Chlamydia pneumoniae seropositivity and aortic atherosclerotic plaques in the general population. BACKGROUND: Seroepidemiologic studies suggest that C pneumoniae infection plays a role in the pathogenesis of atherosclerosis. METHODS: Transesophageal echocardiography was performed in 385 subjects (median age 66 years, range 51 to 101 years; 53% men), a sample of the Olmsted County (Minnesota) population. The association between C pneumoniae immunoglobulin (Ig) G antibody titers and aortic atherosclerotic plaques was examined. RESULTS: Chlamydia pneumoniae IgG antibodies (titers >or=1:16) were detected in 287 subjects (74.5%): low titers (1:16 to 1:32) in 58 (15.1%), intermediate titers (1:64 to 1:128) in 144 (37.4%), and high titers (>or=1:256) in 85 subjects (22.1%). Antibody titers were not associated with the presence of aortic plaques after adjustment for age, gender, and smoking status (p = 0.64). Compared with titers <1:16, the adjusted odds ratios for aortic plaques were 1.46 (95% confidence interval [CI] 0.63 to 3.42) for low titers, 1.32 (95% CI 0.68 to 2.55) for intermediate titers, and 0.94 (95% CI 0.42 to 2.07) for high titers. Among the subgroup with plaques, antibody titers were not associated with the presence of plaques >or=4 mm thick (p = 0.99), plaques >or=6 mm (p = 0.49), or mobile debris (p = 0.71), after adjustment for age and smoking. CONCLUSIONS: Chlamydia pneumoniae IgG antibody titers are not associated with the presence or severity of aortic atherosclerosis in the general population. These observations do not support a role for C pneumoniae infection in the initiation or progression of atherosclerosis.  相似文献   
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OBJECTIVES: The study determined, in a population-based setting, whether dilatation of the thoracic aorta is an atherosclerosis-related process. BACKGROUND: The role of atherosclerosis in thoracic aortic dilatation and aneurysm formation is poorly defined. METHODS: The dimensions of the thoracic aorta were measured with transesophageal echocardiography in 373 subjects participating in a population-based study (median age 66 years; 52% men). The associations between clinical and laboratory atherosclerosis risk factors, aortic atherosclerotic plaques, and aortic dimensions were examined. RESULTS: Age, male gender, and body surface area (BSA) jointly accounted for 41%, 31%, 38%, and 47% of the variability in diameters of the sinuses of Valsalva, ascending aorta, aortic arch, and descending aorta, respectively. Adjusting for age, gender, and BSA: 1) smoking was associated with a greater aortic arch diameter, and diastolic blood pressure and diabetes were each associated with a greater descending aorta diameter (p < 0.05); 2) atherosclerotic plaques in the descending aorta were associated with a greater descending aorta diameter (0.18 +/- 0.08-mm increase in diameter per 1-mm increase in plaque thickness; p = 0.02); and 3) minor negative associations were noted between atherosclerotic plaques and risk factors for atherosclerosis and the dimensions of the proximal thoracic aorta. Notably, atherosclerosis risk factors and plaque variables each accounted for <2% of the variability in aortic dimensions, adjusting for age, gender, and BSA. CONCLUSIONS: Age, gender, and BSA are major determinants of thoracic aortic dimensions. Atherosclerosis risk factors and aortic atherosclerotic plaques are weakly associated with distal aortic dilatation, suggesting that atherosclerosis plays a minor role in aortic dilatation in the population.  相似文献   
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The purpose of this study was to investigate whether low cerebral blood flow (CBF) is associated with subsequent development of white matter hyperintensities (WMH). Patients were included from a longitudinal magnetic resonance (MR) imaging study of minor stroke/transient ischemic attack patients. Images were co-registered and new WMH at 18 months were identified by comparing follow-up imaging with baseline fluid-attenuated inversion recovery (FLAIR). Regions-of-interest (ROIs) were placed on FLAIR images in one of three categories: (1) WMH seen at both baseline and follow-up imaging, (2) new WMH seen only on follow-up imaging, and (3) regions of normal-appearing white matter at both time points. Registered CBF maps at baseline were used to measure CBF in the ROIs. A multivariable model was developed using mixed-effects logistic regression to determine the effect of baseline CBF on the development on new WMH. Forty patients were included. Mean age was 61±11 years, 30% were female. Low baseline CBF, female sex, and presence of diabetes were independently associated with the presence of new WMH on follow-up imaging. The odds of having new WMH on follow-up imaging reduces by 0.61 (95% confidence interval=0.57 to 0.65) for each 1 mL/100 g per minute increase in baseline CBF. We conclude that regions of white matter with low CBF develop new WMH on follow-up imaging.  相似文献   
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Mitral annular velocities are reportedly useful in diagnosing constrictive pericarditis (CP); however, their exact efficacy in larger clinical settings remains unevaluated. This study reexamined the role of longitudinal tissue Doppler imaging in diagnosing CP in clinical practice. Tissue velocity imaging (GE Vingmed System Five) was performed in 122 subjects (87 referred with clinically suspected CP and 35 age- and sex-matched controls). Of the 87 subjects with suspected CP, 45 (51.7%) had CP confirmed at surgery, 11 (12.6%) had restrictive heart disease, 20 (23.0%) had right heart failure due to cor pulmonale, and the other 11 (12.6%) had old pericardial effusions and no hemodynamic evidence of constriction on follow-up echocardiography. Of the 45 patients with CP, mitral early diastolic (Ea) annular velocities from septal and lateral regions were normal (>/=8 cm/s) in 40 (88.9%) and decreased (<8 cm/s) in 1 or both regions in 5 (3 with left ventricular systolic dysfunction, 2 with extensive mitral annular calcification). Of 11 patients with restrictive cardiomyopathy, 8 (72.7%) had reduced Ea (<8 cm/s) and 3 showed normal Ea velocity in 1 or both corners of the mitral annulus. All except 2 patients with right-sided heart failure from cor pulmonale and those with previous pericardial effusion had normal Ea velocities. A normal Ea velocity improved recognition of CP, particularly in the presence of nondiagnostic 2-dimensional or transmitral flow-Doppler imaging. The overall sensitivity and specificity for diagnosing CP using tissue Doppler incrementally with M-mode, 2-dimensional, and transmitral flow Doppler were 88.8% and 94.8%, respectively. Mitral annular velocities help with diagnosis and differentiation of CP in most cases, except in the presence of extensive annular calcification, left ventricular systolic dysfunction, or segmental nonuniformity in myocardial velocities.  相似文献   
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