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61.
Ischaemia and reperfusion phases represent critical events during liver transplantation. The purpose of this study was to describe morphological alterations of both vascular and parenchymal compartments after ischaemia and reperfusion and to evaluate the possible relationship between morphometric parameters and biochemical/clinical data. Three needle biopsies were drawn from 20 patients who underwent orthotopic liver transplantation. The first biopsy was taken before flushing with preservation solution, and the second and the third to evaluate respectively the effects of cold ischaemia and of warm ischaemia/reperfusion. Biopsies were examined by an image analyser and morphometric parameters related to the liver parenchyma were evaluated. At the second biopsy we observed a decrease of the endothelium volume fraction while the same parameter referred to the sinusoidal lumen achieved a peak value. The hepatocytes showed a lower surface parenchymal/vascular sides ratio. This parameter was reversed at the end of the reperfusion phase; furthermore the third biopsy revealed endothelial swelling and a decreased volume fraction of the sinusoidal lumen. The results quantify the damage to the sinusoidal bed which, as already known, is one of the main targets of cold ischaemia; warm ischaemia and reperfusion accentuate endothelial damage. The end of transplantation is characterised by damage chiefly to parenchymal cells. Hepatocytes show a rearrangement of their surface sides, probably related to the alterations of the sinusoidal bed. In addition, the fluctuations of morphometric parameters during ischaemia/reperfusion correlate positively with biochemical data and clinical course of the patients.  相似文献   
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Background. Treatment of wrinkles has become an increasing problem for dermatologists. Hyaluronic acid is a component of the family of glycosaminoglycans (GAGS, substances known for their property of retaining water), that significantly decreases with aging and in wrinkles. A new technique that uses a specific pulsed electromagnetic field, electrorydesis, has been introduced in the treatment of wrinkles associated with aging. The treatment is based on the reported in vitro effects of specific electromagnetic fields on fibroblast cultures (e.g., an increase in DNA synthesis and in the production of collagen and presumably also of GAGS). Methods. The in vivo effects of the electromagnetic field on aged skin (3 subjects aged 50, 56 and 60 years), with particular focus on the ultrastructural modifications and GAGS amount before and after the treatment, were evaluated by electron microscope. Results. The ultrastructural study (tissue stained with al-cian blue) showed after treatment a significant increase (p < 0.005) of the electron-dense granules (corresponding to hyaluronic acid), located in collagen elastic fibers, and in the soluble matrix. This presumably leads to subsequent edema that was clinically evident after the treatment. Conclusions. These data suggest that the increased levels of GAGS and the subsequent edema of the dermis could explain at least in part the clinical changes observed after electrorydesis treatment (e.g., swelling and “disappearance” of the wrinkle).  相似文献   
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Background: Radiofrequency catheter ablation is a well-established approach to treating several types of cardiac arrhythmias. The aim of our study was to provide data on the diffusion of catheter ablation procedures in clinical practice through a meta-analysis of National Registries of electrophysiological procedures performed over a 5-year period, from 2000 to 2005.
Methods: We found only two national registries of catheter ablation procedures published in the journals indexed in PubMed: The Spanish Catheter Ablation Registry and the Portuguese National Registry on Cardiac Electrophysiology. In addition, we included in our analysis the data from the Italian Registry of Electrophysiological Procedures.
Results and Conclusions: This meta-analysis revealed a steady increase in the total number of catheter ablation procedures, particularly for the ablation of atrial flutter, of tachycardia due to double nodal pathways, and of the left atrial substrate in atrial fibrillation. However, the progress of catheter ablation and the impetus for additional research and development of new approaches and technologic advances requires further data on clinical indications, methodologic approach, complications, and long-term success rate in the real world.  相似文献   
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We present a case of a young boy who had an implantable cadrioverter defibrillator implanted for refractory syncope and cathecolaminergic polymorphic ventricular tachycardia (CPVT). The patient underwent an electrical storm with multiple shocks and serious compromise of quality of life and risk. The pharmacological options are discussed as well as the strategies of managing ventricular arrhythmias in CPVT. (PACE 2010; 33:e27–e31)  相似文献   
65.
A POSTOPERATIVE PROGNOSTIC NOMOGRAM FOR RENAL CELL CARCINOMA   总被引:8,自引:0,他引:8  
PURPOSE: Few published studies have combined prognostic factors to predict the likelihood of recurrence after surgery for renal cell carcinoma. We developed a nomogram for this purpose. MATERIALS AND METHODS: With Cox proportional hazards regression analysis, we modeled pathological data and disease followup for 601 patients with renal cell carcinoma who were treated with nephrectomy. Predictor variables were patient symptoms, including incidental, local or systemic, histology, including chromophobe, papillary or conventional, tumor size, and pathological stage. Treatment failure was recorded when there was either clinical evidence of disease recurrence or death from disease. Validation was performed with a statistical (bootstrapping) technique. RESULTS: Disease recurrence was noted in 66 of the 601 patients, and those in whom treatment was successful had a median and maximum followup of 40 and 123 months, respectively. The 5-year probability of freedom from failure for the patient cohort was 86% (95% confidence interval 82 to 89). With statistical validation, predictions by the nomogram appeared accurate and discriminating with an area under the receiver operating characteristic curve, that is a comparison of the predicted probability with the actual outcome of 0.74. CONCLUSIONS: A nomogram has been developed that can be used to predict the 5-year probability of treatment failure among patients with newly diagnosed renal cell carcinoma. The nomogram may be useful for patient counseling, clinical trial design and patient followup planning.  相似文献   
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The purpose of this study was to compare the effect of direct percutaneous transluminal coronary angioplasty (PTCA) and intravenous recombinant tissue plasminogen activator (rt-PA) on left ventricular remodeling in patients with acute myocardial infarction (AMI). To address this issue, patients with AMI randomly assigned to direct PTCA or intravenous rt-PA as part of a large multicenter study (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries [GUSTO] IIb Angioplasty Substudy) were evaluated with two-dimensional echocardiography at predischarge. An echocardiographic infarct size index and the end-diastolic and end-systolic left ventricular volumes were computed. Patients with an infarct size index equal to or higher than the mean value were considered to have a large infarction. Of 26 enrolled patients, 13 were assigned to PTCA (9 successfully reperfused: i.e., TIMI-3 flow after PTCA) and 13 to rt-PA (10 successfully reperfused: i.e., ST resolution after rt-PA). In patients considered successfully reperfused, end-systolic volumes tended to be lower in PTCA patients than in rt-PA patients (43 ± 17 cc vs 59 ± 21 cc, P = 0.09), although there were no differences in infarct size index (7.3 ± 2.8 vs 7.0 ± 2.8) and ejection fraction (52%± 10% vs 46%± 12%). End-systolic volume depended on infarct size index in the overall patient population (r = 0.60, P = 0.007) and in rt-PA patients (r = 0.80, P =0.005), while no correlation was found in PTCA patients. Considering patients with large AMIs, end-systolic volumes were higher in the four patients treated with rt-PA than in the four patients treated with direct PTCA (P < 0.01). Considering all the 26 enrolled patients, these differences were also present, but they did not reach statistical significance. In conclusion, our results suggest that, in patients with large AMIs, adequate reperfusion obtained by direct PTCA has a more marked effect in counteracting ventricular remodeling than that obtained by systemic rt-PA. This beneficial effect of direct PTCA, independent of any reduction in regional wall-motion abnormalities, should be taken into account when comparing the clinical value of direct PTCA with that of systemic thrornbolysis in the treatment of AMI.  相似文献   
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