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The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005, in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a priority area for studies on this zoonosis. Given this, the present study provides data on this phenomenon in an urban context, in order to assess the possible circulation of the classic rabies virus (RABV) among bat species in Capanema, a town in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and dry seasons. Samples of brain tissue and blood were collected for virological and serological survey, respectively. None of the 153 brain tissue samples analyzed tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum samples analyzed were seropositive. Artibeus planirostris was the most common species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31 52.60%). Statistically, equal proportions of seropositive results were obtained in the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95% CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested positive for infection, the high proportion of seropositive specimens indicates that RABV may be widespread in this urban area.  相似文献   
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OBJECTIVE: To survey nurses around the world about current practices for peritoneal dialysis (PD) home training programs. DESIGN: Random sampling of nurses to complete a written survey from the International Society for Peritoneal Dialysis Nursing Liaison Committee. Settings: United States, Canada, South America (Brazil, Columbia), The Netherlands, Hong Kong. METHODS: Surveys and responses were sent by fax whenever possible, or by regular mail, or hand carried, or conducted by telephone. Results were stratified by geographic areas as well as by cumulative responses and were expressed as medians with ranges. Kruskal-Wallis was used to evaluate differences in responses. Associations between variables were tested with Pearson correlation. Univariate regression analysis was used to evaluate the impact of variables on peritonitis rates. Variables with p < 0.10 were included in a multivariate analysis. RESULTS: A total of 317 nurses responded: 88 in the United States, 46 in Canada, 58 in South America, 58 in Hong Kong, and 67 in The Netherlands. This represented 37% of all surveys distributed. Respondents had a median of 12 years' experience in nephrology (range 1-35 years), but only 31% had a formal background in adult education. Nearly half received their guidance to patient training from a nurse colleague, 11% were guided by a corporate colleague, and 8% were simply self-taught. Clinics responding had a median of 30 PD patients (range 1-400) and reported they trained a median of 8 patients per year (range 0-86). Reported peritonitis rates were a median 0.46 per year or 1 episode every 26 months. Peritonitis rates, however, were not known by 53% of respondents. Total training time per patient had a very wide range of hours, from 6 to 96. There was no correlation between training time and peritonitis rates among the study respondents (p = 0.38), nor with any other variables. CONCLUSIONS: There is wide variation in practices for PD patient training programs within countries and around the world. Training time did not appear to be related to peritonitis rates. Randomized trials of training practices are needed to determine which approaches produce the best outcomes for patients.  相似文献   
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OBJECTIVE: Gelastic seizures are a frequent and well established manifestation of the epilepsy associated with hypothalamic hamartomas. The scalp EEG recordings very seldom demonstrate clear spike activity and the information about the ictal epilepsy dynamics is limited. In this work, we try to isolate epileptic rhythms in gelastic seizures and study their generators. METHODS: We extracted rhythmic activity from EEG scalp recordings of gelastic seizures using decomposition in independent components (ICA) in three patients, two with hypothalamic hamartomas and one with no hypothalamic lesion. Time analysis of these rhythms and inverse source analysis was done to recover their foci of origin and temporal dynamics. RESULTS: In the two patients with hypothalamic hamartomas consistent ictal delta (2-3 Hz) rhythms were present, with subcortical generators in both and a superficial one in a single patient. The latter pattern was observed in the patient with no hypothalamic hamartoma visible in MRI. The deep generators activated earlier than the superficial ones, suggesting a consistent sub-cortical origin of the rhythmical activity. CONCLUSIONS: Our data is compatible with early and brief epileptic generators in deep sub-cortical regions and more superficial ones activating later. SIGNIFICANCE: Gelastic seizures express rhythms on scalp EEG compatible with epileptic activity originating in sub-cortical generators and secondarily involving cortical ones.  相似文献   
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The aim of the project was to assess the effectiveness and safety of weekly epoetin-beta (EB) in patients with gastrointestinal cancer (GIC) subjected to concomitant chemoradiotherapy (CCTRT).  相似文献   
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Hypoxia is related to poor prognosis because it is associated to chemo-and radioresistance. During recent years the evolution of imaging methods like PET/CT and MRI has meant the appearance of new perspectives with direct implications in radiation therapy. We discuss previous experiences in staging, planning and in the follow-up process with these techniques for measuring tumour hypoxia.  相似文献   
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One of the important steps on the road to becoming expert in a motor skill occurs when the individual can perform the movements in a seemingly effortless and automatic fashion. The authors review two lines of investigations, namely, fMRI and mathematically guided studies of the dynamics of skill acquisition, that suggest that this road to automatic involves two steps: (1) an increasing reliance on the self-regulatory aspects of the motor task, and (2) a minimization of the role of mechanisms based on intentionally directed corrective movements. The interplay between these two mechanisms implies that, at a given skill level, performance decreases whenever intention intervenes. The observation that psychological factors may be as important as mechanical repetition for the development of expertise has important implications for the design of neurorehabilitative strategies.  相似文献   
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