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131.
Sinusoidal hemangioma, characterized by interconnecting thin-walled vascular spaces, may present papillae/pseudo-papillae and zones that resemble intravascular papillary endothelial hyperplasia (IPEH). Our objectives are to explore the existence of zones in IPEH with sinusoidal hemangioma characteristics, the mechanism of papillary and septa formation in sinusoidal hemangioma and the comparison of this mechanism with that in IPEH. For these purposes, specimens of 4 cases of each entity were selected and studied by serial histologic sections and by immunochemistry and immunofluorescence procedures. The results showed a) zones with characteristics of sinusoidal hemangioma in IPEH cases, b) presence in both entities of papillae with a cover formed by a monolayer of CD34+ and CD31+ endothelial cells (ECs) and a core formed by either type I collagen and αSMA+ cells (presenting a pericyte/smooth muscle cell aspect) or thrombotic components, and c) a similar piecemeal angiogenic mechanism in papillary formation, including sprouting of intimal ECs toward the vessel wall itself or intravascular thrombi, formation of vascular loops that encircle and separate vessel wall or thrombus components, and parietal or thrombotic papillae development. The major differences between both entities were the number, arrangement and substrate of papillae: myriad, densely grouped, parietal and thrombotic papillae in IPEH, and a linear arrangement of predominant parietal papillae in sinusoidal hemangioma, originating septa (segmentation). In conclusion, sinusoidal hemangioma and IPEH are interrelated processes, which share morphologic findings and a piecemeal angiogenic mechanism, combining sprouting and intussusceptive angiogenesis, and leading to papillary formation and vessel segmentation.  相似文献   
132.
Event-related desynchronization/synchronization (ERD/ERS) of alpha and beta electroencephalographic (EEG) rhythms was investigated in normal subjects and mild Alzheimer Disease patients (AD), performing unilateral right finger movements (about 10 s intermovement interval). Electroencephalographic data were sampled based on 10-20 system electrode montage. Surface Laplacian estimate of the potential reduced the head-volume conductor effects and annulled electrode reference variations. Results showed that EEG reactivity (i.e., ERD/ERS) of modeled contralateral rolandic cortex and motor performance were preserved in mild to moderate AD. In contrast, modeled activity (i.e., ERD/ERS) of frontolateral, centromedial, and ipsilateral rolandic areas was abnormal. Furthermore, interrelatedness of cortical response and movement timing was abnormal in AD patients. These results would support the working hypothesis that mild to moderate AD is a global brain network disease, including processing of sensorimotor information (despite no overt movement disorder). Further investigations will ascertain the clinical relevance of these results.  相似文献   
133.
Summary. We studied the correlation between density-dependence parameters (ΔHe, volume of isoflow) and age, body build, spirography and forced expiratory flows in 69 healthy non-smokers (16 females) aged 18 to 51 years. Density dependence variables showed no significant differences between young (less than 35 years) males and females. Volume of isoflow per cent of forced vital capacity (Viso V?% FVC) was poorly significantly related to age (r=+ 0·25 P < 0·05) and weight (r =+ 0·27 P <0·05). Significant correlations were found between density dependence at low lung volume and the FEV1/VC ratio (r = 0·31, P= 0·01 for ΔHe 25%; r=-0.40, P < 0·001 for Viso V?% FVC) or the forced expiratory flows with air (Viso 0% FVC vs. FEF 25% r=-0.42, P<0·001). These correlations were closer in females as compared to males. Volume of isoflow was well related to ΔHe 25%r= 0·64, P<0·001), but the relationship with ΔHe 50% was weaker (r=-0·38; P< 0·01).  相似文献   
134.
Quadricuspid aortic valves are rare congenital anomalies, usually diagnosed in adult patients affected by severe aortic regurgitation. We have now encountered three such valves in children undergoing transthoracic echocardiography. All children were asymptomatic. The first child possessed a valve with two larger leaflets, and smaller leaflets of equal size. In the second child, 3 leaflets were of equal size, with 1 small accessory leaflet. The third child had a valve with four leaflets of approximately equal size. In one child, the aortic valve was functioning normally, and came to attention because of mitral valvar prolapse causing mild regurgitation. In the remaining two children, central mild aortic regurgitation was detected using colour flow analysis, and associated dilation of the aortic root was revealed by measurements of the cross-sectional images.  相似文献   
135.
BACKGROUND: A recognized drawback of ST-elevation acute myocardial infarction (STEMI) after fibrinolysis is persistent coronary occlusion or a less than TIMI 3 flow. The present study describes the results of systematic pre-discharge coronary angiography and revascularization, whenever indicated, following fibrinolytic therapy for STEMI. METHODS: Consecutive patients admitted with the diagnosis of STEMI between April 1, 2000 and April 30, 2002 were included in the study. Patients with contraindications to thrombolytic therapy and/or patients not eligible for angiography were excluded. All patients received "accelerated" treatment with alteplase and had a coronary angiography at least 24 hours later, in order to perform, if anatomically feasible, angioplasty with stenting. Angioplasty of non-infarct-related coronary arteries was allowed. The mortality, reinfarction and new revascularization rates were evaluated during index hospitalization and up to 30 days and 6 months. RESULTS: Eighty patients underwent cardiac catheterization at a median of 6.5 days following admission; in 86.3% of cases a patent infarct-related artery was found; in 71% of patients a coronary angioplasty was performed, with stenting in 88% of cases. Procedure-related complications were infrequent. No deaths occurred during hospitalization and at 30 days; at 6 months the mortality rate was 1.3%. In-hospital reinfarction occurred in 3.8% of patients, in 4% at 30 days and in 5.3% at 6 months. The rate of any new revascularization was 2.6% at 30 days and 11% at 6 months. CONCLUSIONS: Although obtained in a small observational study, our data, unlike those from previous studies, suggest that an invasive strategy after fibrinolysis in STEMI is safe and associated with low mortality and morbidity rates in the short and medium-terms.  相似文献   
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OBJECTIVES: High levels of plasma high sensitivity C-reactive protein (CRP), sensitive to therapy with statins, have been described in hypercholesterolaemia. In vitro evidence shows that CRP activates the complement system, which, in turn, leads to an increased expression of ICAM-1. Our objectives were to verify whether primary hypercholesterolaemia (PHC) is associated with an upregulation of the inflammatory/immune response, and whether this is sensitive to atorvastatin. METHODS AND RESULTS: We examined the levels of sICAM-1, C3, C4 complement fractions in 48 patients with PHC, with (CAD group) or without (No-CAD group) coronary artery disease (CAD) in comparison with a group of 48 healthy controls. The two patient groups were studied before and after atorvastatin therapy. Both hypercholesterolaemic groups showed higher mean values of sICAM-1, C3 and C4 (P < 0.0001) when compared with the controls. The two groups of patients responded differently to atorvastatin therapy. After 3 months, the C3 levels normalized in both groups of patients (P < 0.02 compared with basal values); C4 was greatly reduced only in the CAD group (P < 0.01). After 12 months of therapy, in CAD group C3 mean levels were still significantly lower than baseline values (P < 0.01); a further decrease in the C4 values (P < 0.05 with respect to levels after 3 months of therapy) and also a substantial reduction in sICAM-1 values (P < 0.001 with respect to basal values) were observed. CONCLUSIONS: High plasma values of C3 and C4 in PHC cluster with high values of sICAM-1, distinguish subjects with CAD and could be used to monitor the anti-inflammatory effect of statin therapy in these patients.  相似文献   
140.
IntroductionHypertensive heart disease is manifested by structural and functional adaptations of the myocardium that lead to heart failure, mainly diastolic, especially in women older than 65 years.ObjectivesThe ejection fraction of the left ventricle, which is considered an image of systolic function, represents instead an indicator less closely related to the complex ventricular remodeling, responsible for the variety of clinical aspects of hypertensive heart disease. Above all, it seems to be incorrect that the boundary between function “preserved” or “not preserved” is reflected only in the value of the ejection fraction of 50%. Anatomical and functional considerations of the structure of the ventricles and of the way in which they contract and release, suggest a need to reconsider the excessive value that is currently ascribed to this parameter.ConclusionsModern echocardiography with tissue Doppler and speckle tracking, may provide the means to objectively evaluate and quantify this new point of view.  相似文献   
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