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Spira Elana Greenfield; Bracken Stacey Storch; Fischel Janet E. 《Canadian Metallurgical Quarterly》2005,41(1):225
This study investigated the role of early literacy and behavioral skills in predicting the improvement of children who have experienced reading difficulties in 1st grade. The progress of 146 low-income children whose reading scores in 1st grade were below the 30th percentile was examined to determine (a) how the poorest readers in 1st grade progressed in reading achievement through 4th grade and (b) which emergent literacy and behavioral skills measured in kindergarten predicted differential 4th grade outcomes. Results indicated that the divergence between children who improved and those who did not was established by the end of 2nd grade. Further, individual linguistic skills and behavioral attributes measured in kindergarten contributed substantively to this difference. Implications for intervention timing and educational policy are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Multifocal electroretinograms were recorded from twelve subjects on three separate days using the Visual Evoked Response Imaging System (VERIS). The subjects were 18-40 years-of-age. Each recording session was separated by an interval of between one and 16 weeks. Four electrode types were compared: the JET contact lens electrode, the gold foil electrode, the DTL thread electrode and the carbon fibre (c-glide) electrode. The b-wave amplitude density (nV/sq.deg) recorded with each electrode was measured. The mean amplitude density recorded at each session for each subject and each electrode was calculated and compared. There were no significant differences in amplitude density for the ERGs recorded with each type of electrode over the three days. The coefficient of variation for each electrode and each subject was then calculated using the results for the three days. The coefficients of variation for each electrode showed significant differences (One-way ANOVA: F = 4.51, d.f. = 3.44, P < 0.008). The c-glide electrode results had the highest variability and post hoc tests showed that its coefficient of variation was significantly different from those of the JET and gold foil electrodes but not from that of the DTL thread electrode. 相似文献
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M Fainzilber A Hasson R Oren AL Burlingame D Gordon ME Spira E Zlotkin 《Canadian Metallurgical Quarterly》1994,33(32):9523-9529
Two mollusc-specific neurotoxic peptides from the venom of the molluscivorous snail Conus pennaceus are described. These new toxins block acetylcholine receptors (AChR) of cultured Aplysia neurons. Bath application of 0.5-1 microM toxin induces 5-10-mV membrane depolarization, which recovers to the control level within 1-3 min in the presence of the toxin. This response is blocked by 1 mM hexamethonium. Concomitantly with the transient depolarization, the toxins block approximately 90% of the depolarizing responses evoked by brief iontophoretic application of acetylcholine. The pharmacology and amino acid sequences of the toxins (alpha PnIA, GCCSLPPCAANNPDYC-NH2; alpha PnIB, GCCSLPPCALSNPDYC-NH2) enable their classification as novel alpha-conotoxins. The sequences differ from those of previously described alpha-conotoxins in a number of features, the most striking of which is the presence of a single negatively charged residue in the C-terminal loop. This loop contains a positively charged residue in piscivorous venom alpha-conotoxins. In contrast to other alpha-conotoxins, which are selective for vertebrate skeletal muscle nicotinic ACh receptors, these Conus pennaceus toxins block neuronal ACh receptors in molluscs. As such they are new probes which can be used to define subtypes of ACh receptors, and they should be useful tools in the study of structure-function relationships in ACh receptors. 相似文献
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Fish-odor syndrome is due to a rare metabolic defect in which there is massive excretion of the volatile tertiary amine, trimethylamine (TMA) in the urine. The typical fish-like odor of TMA also appears on the breath or in the sweat of affected individuals. In normal man TMA is oxidized to its odorless N-oxide derivative. TMA is of dietary origin, formed by intestinal bacterial degradation of the choline in egg yolk, liver, soybeans, etc., or by reduction of TMA-oxide present in high concentrations in marine fish. 2 sisters with the tentative diagnosis of trimethylaminuria are presented. 相似文献
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"Pseudo-obstruction of the colon" refers to a condition in which physical and radiological findings identical to those associated with mechanical obstruction of the large bowel are found but in which no organic cause for the colonic distention is present. These cases may involve progressive proximal large bowel dilatation to the point of cecal perforation or necrosis. We have collected eight cases of our own which will be presented. The various etiologic factors reported in the literature will be discussed and analyzed and we will offer an anatomicophysiologic explanation of a possible mechanism, based on sympathetic-parasympathetic neurostimulatory imbalance. 相似文献
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