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Delayed contrast enhancement after injection of a gadolinium-chelate (Gd-chelate) is a reference imaging method to detect myocardial tissue changes. Its localization within the thickness of the myocardial wall allows differentiating various pathological processes such as myocardial infarction (MI), inflammatory myocarditis, and cardiomyopathies. The aim of the study was first to characterize benign myocarditis using quantitative delayed-enhancement imaging and then to investigate whether the measure of the extracellular volume fraction (ECV) can be used to discriminate between MI and myocarditis.In 6 patients with acute benign myocarditis (32.2 ± 13.8 year-old, subepicardial late gadolinium enhancement [LGE]) and 18 patients with MI (52.3 ± 10.9 year-old, subendocardial/transmural LGE), myocardial T1 was determined using the Modified Look-Locker Imaging (MOLLI) sequence at 3 Tesla before and after Gd-chelate injection. T1 values were compared in LGE and normal regions of the myocardium. The myocardial T1 values were normalized to the T1 of blood, and the ECV was calculated from T1 values of myocardium and blood pre- and post-Gd injection.In both myocarditis and MI, the T1 was lower in LGE regions than in normal regions of the left ventricle. T1 of LGE areas was significantly higher in myocarditis than in MI (446.8 ± 45.8 vs 360.5 ± 66.9 ms, P = 0.003) and ECV was lower in myocarditis than in MI (34.5 ± 3.3 vs 53.8 ± 13.0 %, P = 0.004).Both inflammatory process and chronic fibrosis induce LGE (subepicardial in myocarditis and subendocardial in MI). The present study demonstrates that the determination of T1 and ECV is able to differentiate the 2 histological patterns.Further investigation will indicate whether the severity of ECV changes might help refine the predictive risk of LGE in myocarditis.  相似文献   
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An analysis of the effects of natural (vitamin A) and synthetic retinoids on experimental carcinogenesis of the urinary bladder indicates that inhibitory activity is carcinogen‐ or carcinogen‐class‐specific. These findings suggest that there may be more than one pathway for the neo‐differentiation of urothelial cells to frank carcinoma and that these pathways may be related to both carcinogen class and dietary vitamin A status.  相似文献   
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L. Rosow, J.X. Jiang, T. Deuel, M. Lechpammer, A.A. Zamani, D.A. Milner, R. Folkerth, F.M. Marty, S. Kesari. Cerebral phaeohyphomycosis caused by Bipolaris spicifera after heart transplantation.
Transpl Infect Dis 2011: 13: 419–423. All rights reserved Abstract: Phaeohyphomycosis is an increasingly recognized cause of brain abscess in both immunocompetent and immunocompromised hosts. We report a case of cerebral phaeohyphomycosis in a 55‐year‐old male heart transplant recipient caused by Bipolaris spicifera. We review the literature regarding the pathogenesis, epidemiology, diagnosis, and management of infections with dematiaceous fungi.  相似文献   
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A 10% random sample of 3543 cases litigated in the United States’ civil and criminal courts were analysed using logistic regression to develop a model that can predict case outcomes for litigants with schizophrenia. Most predictors are related to case characteristics and not to the litigants’ antecedents, behaviours or medication issues. Only the psychologist as an expert witness was found to be related to case outcome, but the concern is expressed that inadequate weight is given to expert testimony. Other significant findings include being represented by counsel, atypical medication and malingering.  相似文献   
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To distinguish between different models of vesicular release in brain synapses, it is necessary to know the number of vesicles of transmitter that can be released immediately at individual synapses by a high-calcium stimulus, the readily releasable pool (RRP). We used direct stimulation by calcium uncaging at identified, single-site inhibitory synapses to investigate the statistics of vesicular release and the size of the RRP. Vesicular release, detected as quantal responses in the postsynaptic neuron, showed an unexpected stochastic variation in the number of quanta from stimulus to stimulus at high intracellular calcium, with a mean of 1.9 per stimulus and a maximum of three or four. The results provide direct measurement of the RRP at single synaptic sites. They are consistent with models in which release proceeds from a small number of vesicle docking sites with an average occupancy around 0.7.  相似文献   
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Vascularized composite tissue allotransplantation is a viable treatment option for injuries and defects that involve multiple layers of functional tissue. In the past 15 yr, more than 150 vascularized composite allotransplantation (VCA) surgeries have been reported for various anatomic locations including – but not limited to – trachea, larynx, abdominal wall, face, and upper and lower extremities. VCA can achieve a level of esthetic and functional restoration that is currently unattainable using conventional reconstructive techniques. Although the risks of lifelong immunosuppression continue to be an important factor when evaluating the benefits of VCA, reported short‐ and long‐term outcomes have been excellent, thus far. Acute rejections are common in the early post‐operative period, and immunosuppression‐related side effects have been manageable. A multidisciplinary approach to the management of VCA has proven successful. Reports of long‐term graft losses have been rare, while several factors may play a role in the pathophysiology of chronic graft deterioration in VCA. Alternative approaches to immunosuppression such as cellular therapies and immunomodulation hold promise, although their role is so far not defined. Experimental protocols for VCA are currently being explored. Moving forward, it will be exciting to see whether VCA‐specific aspects of allorecognition and immune responses will be able to help facilitate tolerance induction.  相似文献   
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