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Enlarged perivascular spaces (EPVS), visible in brain MRI, are an important marker of small vessel disease and neuroinflammation. We systematically evaluated the literature up to June 2012 on possible methods for their computational assessment and analyzed confounds with lacunes and small white matter hyperintensities. We found six studies that assessed/identified EPVS computationally by seven different methods, and four studies that described techniques to automatically segment similar structures and are potentially suitable for EPVS segmentation. T2‐weighted MRI was the only sequence that identified all EPVS, but FLAIR and T1‐weighted images were useful in their differentiation. Inconsistency within the literature regarding their diameter and terminology, and overlap in shape, intensity, location, and size with lacunes, conspires against their differentiation and the accuracy and reproducibility of any computational segmentation technique. The most promising approach will need to combine various MR sequences and consider all these features for accurate EPVS determination. J. Magn. Reson. Imaging 2013;38:774–785. © 2013 Wiley Periodicals, Inc.  相似文献   
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ObjectiveTo evaluate the performance and quality of the 10 groups of training tasks envisaged in the portfolio training model undertaken by all residents of the Primary Care Teaching Unit in Murcia.DesignA cross-sectional study was conducted on the portfolios provided and completed by all residents in May 2011.ParticipantsAll residents who were in training at that time (131).MethodTen groups of training tasks were established from those recommended by the National Commission for the specialty. The performance of each one in each of the portfolios was evaluated, and the compliance for each training task was calculated. The quality of the performance of each of the tasks was given a score, 0 points (very poor) to 10 points (excellent).ResultsAs regards compliance, the tasks that were most performed were: filling in the Resident book correctly and using the resident skills guide, both with 99.24%, followed by reflection reports on the training visits. All tasks had a compliance rate higher than 67%. The mean percentage of compliance was 86.49%. All tasks obtained an average score greater than 7 (outstanding). The overall mean score was 7,8 points.ConclusionsThe level of perfomance of the tasks set out in the portfolio by the residents was very satisfying. It is necessary to continue working on improving the performance of the portfolio.  相似文献   
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The attentional and motivational significance of cardiac defense is examined in two studies. In Study 1, cardiac defense was evoked by an intense acoustic stimulus in the context of either a visual search or a memory search task using letters as stimuli. Results showed a potentiation of the long latency acceleration of cardiac defense in the visual search task. In Study 2, participants performed the same visual search task using pleasant, neutral, and unpleasant pictures as stimuli. Results showed a further potentiation of the long latency acceleration of cardiac defense when the visual search task was performed with unpleasant, compared to pleasant or neutral pictures. These results indicate that cardiac defense has both attentional and motivational contributions, where the attentional significance is related to increased sensory processing, whereas the motivational significance is associated with preparation for active defense.  相似文献   
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Background  

The prevalence of morbid obesity has seen an increase in developed countries over recent years. Bariatric surgery is almost the only effective strategy for treating super morbidly obese patients. The objective of the study was to evaluate the effects of bariatric surgery on the evolution of the main variables related to diabetes and obesity, especially insulin resistance, parameters of oxidative stress, and inflammatory markers in the early stage after surgery.  相似文献   
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Grupo de Estudio de la Sobrevida en la Insuficiencia Cardiaca en Argentina (GESICA) studied whether a standardized protocol for the initiation and titration of the β-blocker carvedilol in a multicenter, open-label program would optimize β-blocker use in heart failure (HF) patients. The program included: (1) the carvedilol initiation and titration period, and (2) long-term follow-up at 6 and 12 months. Of 1299 patients in the registry, 504 were excluded due to current therapy; of the remaining 795 eligible patients, 293 were excluded due to contraindications. Of the included patients with follow-up data (n = 316), 93.3% tolerated carvedilol initiation and 47.7% of the patients reached the target dose of 50 mg/day for a mean dose of 39 mg/day. Rates were comparable in the elderly (n = 83), of which 53% achieved a target dose for a mean dose of 43.08 mg/day. This protocol improved therapy rates and achieved target doses quickly (average of 4 visits). Concomitant medications did not have to be adjusted and there were low withdrawal rates (10%) and hospital admissions (7.2%) for HF. Patients were able to maintain carvedilol therapy at 6 and 12 months. These results indicate that a standardized titration protocol, as used in GESICA, for the initiation and titration of β-blockers is well tolerated and may improve β-blocker use in carefully selected heart failure patients.The study authors are members of the GESICA Steering Committee and Subcommittees  相似文献   
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