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Journal of the Association for Research in Otolaryngology - Cochlear implant (CI) users show limited sensitivity to the temporal pitch conveyed by electric stimulation, contributing to impaired...  相似文献   
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The aim of this safety study in mice was to determine in vivo toxicity and biodistribution potential of a single and multiple doses of L-glutamic acid-g-p(HEMA) polymeric nanoparticles as a drug delivery system. The single dose did not cause any lethal effect, and its acute oral LD50 was >2.000 mg/kg body weight (bw). Multiple doses (25, 50, or 100 mg/kg bw) given over 28 days resulted in no significant differences in body and relative organ weights compared to control. These results are supported by biochemical and histological findings. Moreover, nanoparticle exposure did not result in statistically significant differences in micronucleus counts in bone marrow cells compared to control. Nanoparticle distribution was time-dependent, and they reached the organs and even bone marrow by hour 6, as established by ex vivo imaging with the IVIS® spectrum imaging system. In conclusion, L-glutamic acid-g-p(HEMA) polymeric nanoparticles appear biocompatible and have a potential use as a drug delivery system.KEY WORDS: biocompatibility, blood biochemistry, genotoxicity, histology, in vivo toxicity, micronucleus test, polymers  相似文献   
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Graefe's Archive for Clinical and Experimental Ophthalmology - Ferromagnetic foreign bodies (FFB) present during magnetic resonance imaging (MRI) explorations can lead to tissue injury due to...  相似文献   
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Breast Cancer Research and Treatment - The NSABP B-36 compared four cycles of doxorubicin and cyclophosphamide (AC) with six cycles of 5-fluorouracil, epirubicin, and cyclophosphamide (FEC-100) in...  相似文献   
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Glioblastoma is an aggressive and fast-growing brain tumor with poor prognosis. Predicting the expected survival of patients with glioblastoma is a key task for efficient treatment and surgery planning. Survival predictions could be enhanced by means of a radiomic system. However, these systems demand high numbers of multicontrast images, the acquisitions of which are time consuming, giving rise to patient discomfort and low healthcare system efficiency. Synthetic MRI could favor deployment of radiomic systems in the clinic by allowing practitioners not only to reduce acquisition time, but also to retrospectively complete databases or to replace artifacted images. In this work we analyze the replacement of an actually acquired MR weighted image by a synthesized version to predict survival of glioblastoma patients with a radiomic system. Each synthesized version was realistically generated from two acquired images with a deep learning synthetic MRI approach based on a convolutional neural network. Specifically, two weighted images were considered for the replacement one at a time, a T2w and a FLAIR, which were synthesized from the pairs T1w and FLAIR, and T1w and T2w, respectively. Furthermore, a radiomic system for survival prediction, which can classify patients into two groups (survival >480 days and 480 days), was built. Results show that the radiomic system fed with the synthesized image achieves similar performance compared with using the acquired one, and better performance than a model that does not include this image. Hence, our results confirm that synthetic MRI does add to glioblastoma survival prediction within a radiomics-based approach.  相似文献   
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The objective of the present study was to characterize socioeconomic inequalities in the patterns of professionally applied topical fluoride (PATF) in Mexican schoolchildren. A cross-sectional study was carried out on 3029 Mexican schoolchildren. A questionnaire was administered to caregivers to determine sociodemographic, socioeconomic, and behavioral variables. The dependent variable was prevalence of PATF, coded as 0?=?without PATF and 1?=?with PATF, at any point in life, and separately, in the previous year. Various indicators of socioeconomic position were included. Logistic regression was used in the final multivariate analysis. The prevalence of PATF any time in life was 33.8%, while in the previous year it was 11.4%. The variables associated (p?<?0.05) with PATF any time in life were child's older age (OR?=?1.12), older age when tooth brushing started (OR?=?1.57), higher brushing frequency (OR?=?1.60), having health insurance [public (OR?=?1.61) or private (OR?=?1.45)], if family owned a car (OR?=?1.29) and better socioeconomic position [parents' education, second (OR?=?1.48) and third (OR?=?1.75) tertile]. For PATF in the previous year, the variables associated were older age of mother (OR?=?1.03), older age when tooth brushing started (OR?=?1.99), higher brushing frequency (OR?=?1.68), having health insurance [public (OR?=?1.62)] and better socioeconomic position (parents' education, second (OR?=?1.57) and third (OR?=?1.97) tertile). This study suggests the existence of socioeconomic inequalities in PATF, manifested through socioeconomic position, access to health insurance and household having a car. Identifying and addressing PATF inequalities would improve oral health in the child population.

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Journal of Interventional Cardiac Electrophysiology - Delineate retrospectively and prospectively the incidence and characteristics of transient ST-segment elevation during transseptal puncture....  相似文献   
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