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Eduardo Suárez-Castaneda Lorenzo Pezzoli Miguel Elas Rafael Baltrons Elner Osmin Crespin-Elías Oscar A. Rivera Pleitez María Isabel Quintanilla de Campos M. Carolina Danovaro-Holliday 《Vaccine》2014
While assessing immunization programmes, not only vaccination coverage is important, but also timely receipt of vaccines. We estimated both vaccination coverage and timeliness, as well as reasons for non-vaccination, and identified predictors of delayed or missed vaccination, for vaccines of the first two years of age, in El Salvador. 相似文献
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Avila-Akerberg O Chacron MJ 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,210(3-4):353-371
Many neurons display significant patterning in their spike trains (e.g. oscillations, bursting), and there is accumulating evidence that information is contained in these patterns. In many cases, this patterning is caused by intrinsic mechanisms rather than external signals. In this review, we focus on spiking activity that displays nonrenewal statistics (i.e. memory that persists from one firing to the next). Such statistics are seen in both peripheral and central neurons and appear to be ubiquitous in the CNS. We review the principal mechanisms that can give rise to nonrenewal spike train statistics. These are separated into intrinsic mechanisms such as relative refractoriness and network mechanisms such as coupling with delayed inhibitory feedback. Next, we focus on the functional roles for nonrenewal spike train statistics. These can either increase or decrease information transmission. We also focus on how such statistics can give rise to an optimal integration timescale at which spike train variability is minimal and how this might be exploited by sensory systems to maximize the detection of weak signals. We finish by pointing out some interesting future directions for research in this area. In particular, we explore the interesting possibility that synaptic dynamics might be matched with the nonrenewal spiking statistics of presynaptic spike trains in order to further improve information transmission. 相似文献
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Francisco Sendra-Portero Oscar E. Torales-Chaparro Miguel J. Ruiz-Gómez 《European journal of radiology》2012
The purpose of this study was to assess student's performance in the interpretation of images before and after training in radiology, by comparing two groups, 6th-year and 3rd-year students, from two different medical curricula. Students participated in an anonymous evaluation consisting of the interpretation of 12 radiological images accompanied with the salient history and clinical data by answering 60 open-ended questions about technique, anatomy, semiology, and clinics. The number of correct, incorrect and blank responses of each group was used to compare pre- and post-training results. Unpaired two-sample t-test was used to evaluate differences between groups. A significant increase in correct responses was found in both groups after training. The comparison between both groups did not show differences for incorrect answers of the whole test and correct answers about anatomy in the pre-training evaluation. The percentage of correct answers to the median question improved from 15.5% to 53.3% for 6th-year students and from 8.3% to 41.1% for 3rd-year students. The post-training evaluation showed a significant increase of correct answers of 6th-year students with respect to 3rd-year students (mean ± standard deviation 53.6 ± 31.3% and 38.7 ± 29.9% respectively), mainly due to differences in technical and clinical questions. This study provides objective and quantitative evidence of pre- and post-training student skills in image interpretation. The similarities found in the previous level of knowledge and skills of both groups emphasizes the suitable change of the first-time training in radiology, from the 6th to the 3rd year course in medical curricula. 相似文献
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Additive impact of pre‐liver transplant metabolic factors on survival post‐liver transplant 下载免费PDF全文
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Treatment of Rheumatoid Arthritis With Anti–Tumor Necrosis Factor or Tocilizumab Therapy as First Biologic Agent in a Global Comparative Observational Study 下载免费PDF全文