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Axonal transport of metallic salts (nickel or cobalt chloride) has been widely used for the anatomical mapping of neural pathways. We show here that when nickel is introduced into GABAergic neurons it completely eliminates GABA immunolabelling. We have used this property to determine the axonal projections of GABAergic neurons in the stomatogastric system of Crustacea. For example, following nickel backfills from either cut axons or from terminals, GABA immunostaining labels only those GABA-immunoreactive neurons which had not been retrogradely labelled with nickel and hence did not project in the cut nerve or to the neuropile uptake site. By comparing such immunolabelled preparations with those not pretreated with nickel the projection patterns of all the GABA immunoreactive neurons in a given system can be revealed. This effect of nickel appears to be selective for GABA immunostaining, insofar as it does not interfere with the immunodetection of either the peptide proctolin or a FMRFamide-like peptide. This method may prove to be a useful tool for analyzing GABAergic neuronal pathways in the nervous systems of invertebrates.  相似文献   
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Prevention Science - Screening is an essential prevention practice for a number of health conditions. However, screening coverage remains generally low. Studies that investigate determinants of...  相似文献   
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Neutrophil Gelatinase Associated Lipocalin (NGAL) is one of the most promising biomarkers for acute kidney injury (AKI). Although urinary NGAL is intuitively more appropriate to apprehend renal injury, clinical data have accumulated on the potential interest of NGAL measured indifferently in serum or urine. Diagnostic performance of NGAL greatly varies across studies according to different factors such as the type of patients (pediatric versus adult) and the clinical situations (surgery versus intensive care). Overall, NGAL is presented as a useful tool to diagnose and predict AKI outcome but several issues (the absence of a unique pertinent threshold value, the incomplete analytical validation of its measurement and, its apparent limited clinical added value as compared to traditional AKI markers) remain to be addressed in order to definitely recommend its use in clinical practice.  相似文献   
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The aim was to develop and validate an instrument to track online problem poker gamblers with player account‐based gambling data (PABGD). We emailed an invitation to all active poker gamblers on the online gambling service provider Winamax. The 14,261 participants completed the Problem Gambling Severity Index (PGSI). PGSI served as a gold standard to track problem gamblers (i.e., PGSI ≥ 5). We used a stepwise logistic regression to build a predictive model of problem gambling with PABGD, and validated it. Of the sample 18% was composed of online poker problem gamblers. The risk factors of problem gambling included in the predictive model were being male, compulsive, younger than 28 years, making a total deposit > 0 euros, having a mean loss per gambling session > 1.7 euros, losing a total of > 45 euros in the last 30 days, having a total stake > 298 euros, having > 60 gambling sessions in the last 30 days, and multi‐tabling. The tracking instrument had a sensitivity of 80%, and a specificity of 50%. The quality of the instrument was good. This study illustrates the feasibility of a method to develop and validate instruments to track online problem gamblers with PABGD only. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Background  Femoral shaft fractures occur very frequently in children, and their prognosis usually is good. Nonoperative treatment is the gold standard for children under 6 years because of the excellent bony union and the remodelling qualities. Purpose  The aim of this study was to compare two orthopaedic therapeutic methods: skin traction versus immediate reduction. Materials and methods  The study involved 35 children, divided into two groups: in group 1, treatment consisted of skin traction for 21 days followed by hip spica casting; in group 2, an immediate reduction with early hip spica casting was performed. The ranges of motion, the delay before weight bearing, the hospitalisation duration and the required amount of painkillers were recorded. We compared initial shortening, axial, sagittal and rotational alignment, and femoral length discrepancy. We calculated the injured femoral diaphysal overgrowth and correlated it to the fracture type and location and to the initial shortening. Economical variables were also studied. Results  The mean overgrowth was 8.9 mm in group 1 and 8.5 mm in group 2. Three years after the trauma, length discrepancy was 4 mm in group 1 and 1 mm in group 2. Hip spica casting leads to significant reductions in weight-bearing delay, hospitalisation duration and pain. The cost of treatment with skin traction was four times higher (24,472 euros) than that of immediate reduction (6,384 euros). Discussion  Our results are in accordance with the literature. The femoral overgrowth was proportional to the initial shortening. Masculine gender, an oblique fracture and injury of the lower third of the femur were associated with the greatest femoral overgrowth. During the first year of follow-up, the femoral length discrepancy hardly varied after immediate reduction (4 mm), whereas the overgrowth reached 6 mm after skin traction. Overall, immediate hip spica casting leads to significant reductions in weight-bearing delay, hospitalisation duration, complications and costs, while having similar clinical results as traction.  相似文献   
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Pathogenic complex genomic rearrangements are being increasingly characterized at the nucleotide level, providing unprecedented opportunities to evaluate the complexities of mutational mechanisms. Here, we report the molecular characterization of a complex duplication–triplication rearrangement involving exons 45–60 of the DMD gene. Inverted repeats facilitated this complex rearrangement, which shares common genomic organization with the recently described duplication‐inverted triplication–duplication (DUP–TRP/INV‐DUP) events; specifically, a 690‐kb region comprising DMD exons from 45 to 60 was duplicated in tandem, and another 46‐kb segment containing exon 51 was inserted inversely in between them. Taking into consideration (1) the presence of a predicted PRDM9 binding site in the near vicinity of the junction involving two inverted L1 elements and (2) the inherent properties of X–Y chromosome recombination during male meiosis, we proposed an alternative two‐step model for the generation of this X‐linked DMD DUP–TRP/INV‐DUP event.  相似文献   
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