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1.
J Learn Disabil ; 51(1): 55-72, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-27895238

RESUMEN

To evaluate the relative efficacy of two reading programs with and without adjunctive stimulant medication for children with attention-deficit/hyperactivity disorder and comorbid reading disorder (ADHD+RD). Sixty-five children (7-11 years in age) were assigned randomly to one of three intensive remedial academic programs (phonologically or strategy-based reading instruction, or general academic strategy and social skills training) in combination with either immediate-release methylphenidate or placebo. Multiple-blind procedures were used for medication/placebo, given twice daily. Children received 35 hours of instruction in 10 weeks, taught by a trained teacher in a separate school classroom, in small matched groups of 2 to 3. Children's behavior and reading abilities were assessed before and after intervention. Stimulant medication produced expected beneficial effects on hyperactive/impulsive behavioral symptoms (reported by classroom teachers) but none on reading. Children receiving a reading program showed greater gains than controls on multiple standardized measures of reading and related skills (regardless of medication status). Small sample sizes precluded interpretation of possible potentiating effects of stimulant medication on reading skills taught in particular reading programs. Intensive reading instruction, regardless of treatment with stimulant medication, may be efficacious in improving reading problems in children with ADHD+RD and warrants further investigation in a large-scale study.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/terapia , Estimulantes del Sistema Nervioso Central/farmacología , Dislexia/terapia , Metilfenidato/farmacología , Evaluación de Resultado en la Atención de Salud , Educación Compensatoria/métodos , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Trastorno por Déficit de Atención con Hiperactividad/epidemiología , Estimulantes del Sistema Nervioso Central/administración & dosificación , Niño , Terapia Combinada , Comorbilidad , Dislexia/epidemiología , Femenino , Humanos , Masculino , Metilfenidato/administración & dosificación , Prueba de Estudio Conceptual
3.
J Learn Disabil ; 41(4): 333-52, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18560021

RESUMEN

This article explores whether struggling readers from different primary language backgrounds differ in response to phonologically based remediation. Following random assignment to one of three reading interventions or to a special education reading control program, reading and reading-related outcomes of 166 struggling readers were assessed before, during, and following 105 intervention hours. Struggling readers met criteria for reading disability, were below average in oral language and verbal skills, and varied in English as a first language (EFL) versus English-language learner (ELL) status. The research-based interventions proved superior to the special education control on both reading outcomes and rate of growth. No differences were revealed for children of EFL or ELL status in intervention outcomes or growth during intervention. Oral language abilities at entry were highly predictive of final outcomes and of reading growth during intervention, with greater language impairment being associated with greater growth.


Asunto(s)
Dislexia/epidemiología , Dislexia/terapia , Trastornos del Lenguaje/epidemiología , Lenguaje , Multilingüismo , Femenino , Humanos , Masculino , Memoria a Corto Plazo , Fonética , Vocabulario
4.
Mol Phylogenet Evol ; 42(2): 287-97, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16876442

RESUMEN

We infer the phylogenetic relationships of finescale shiners of the genus Lythrurus, a group of 11 species of freshwater minnows widely distributed in eastern North America, using DNA sequences from the ND2 (1047 bp), ATPase8 and 6 (823 bp), and ND3 (421 bp) mitochondrial protein-coding genes. The topologies resulting from maximum parsimony, Bayesian, and maximum likelihood tree building methods are broadly congruent, with two distinct clades within the genus: the L. umbratilis clade (L. umbratilis + L. lirus + (L. fasciolaris + (L. ardens, L. matutinus))) and the L. bellus clade (L. fumeus + L. snelsoni + (L. roseipinnis + (L. atrapiculus + (L. bellus, L. algenotus)))). Support is weak at the base of several clades, but strongly supported nodes differ significantly from prior investigations. In particular, our results confirm and extend earlier studies recovering two clades within Lythrurus corresponding to groups with largely "northern" and "southern" geographic distributions. Several species in this genus are listed in the United States as threatened or of special concern due to habitat degradation or limited geographic ranges. In this study, populations assigned to L. roseipinnis show significant genetic divergence suggesting that there is greater genetic diversity within this species than its current taxonomy reflects. A full accounting of the biodiversity of the genus awaits further study.


Asunto(s)
Cyprinidae/genética , Genes Mitocondriales/genética , Filogenia , Animales , Cyprinidae/clasificación , ADN Mitocondrial/química , ADN Mitocondrial/genética , Evolución Molecular , Variación Genética , Datos de Secuencia Molecular , América del Norte , Análisis de Secuencia de ADN
5.
J Acoust Soc Am ; 119(2): 1143-55, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16521775

RESUMEN

Gap detection thresholds for speech and analogous nonspeech stimuli were determined in younger and older adults with clinically normal hearing in the speech range. Gap detection thresholds were larger for older than for younger listeners in all conditions, with the size of the age difference increasing with stimulus complexity. For both ages, gap detection thresholds were far smaller when the markers before and after the gap were the same (spectrally symmetrical) compared to when they were different (spectrally asymmetrical) for both speech and nonspeech stimuli. Moreover, gap detection thresholds were smaller for nonspeech than for speech stimuli when the markers were spectrally symmetrical but the opposite was observed when the markers were spectrally asymmetrical. This pattern of results may reflect the benefit of activating well-learned gap-dependent phonemic contrasts. The stimulus-dependent age effects were interpreted as reflecting the differential effects of age-dependent losses in temporal processing ability on within- and between-channel gap detection.


Asunto(s)
Envejecimiento/fisiología , Discriminación de la Altura Tonal/fisiología , Acústica del Lenguaje , Percepción del Habla/fisiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Umbral Diferencial/fisiología , Femenino , Humanos , Masculino , Espectrografía del Sonido , Factores de Tiempo
6.
Wilehm Roux Arch Dev Biol ; 186(1): 65-70, 1979 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28305312

RESUMEN

Collagen fibrils with a main period banding of 610 Å and 220 Å in width were observed in the blastocoel of 72-h embryos of the sea urchin,Strongylocentrotus purpuratus. Non-striated fibrils of 50 Å diameter were also observed. The collagen is seen in highest concentration in the vicinity of mesenchyme cells which are richly endowed with endoplasmic reticulum and secretory vesicles. A role for collagen in cell attachment, orientation and spicule formation is discussed.

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