972 resultados para B-6
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A blueprint produced by Westinghouse Electric & MFG. Co. in Pittsburgh, Pennsylvanna. The blueprint is dated 19 August 1903 and is stamped "OBSOLETE".
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Probar los efectos de la grabación de modelos en un laboratorio de CCTV (circuito cerrado de televisión) y en un aula real mediante CPTV (circuito portátil de televisión), así como de los modelos simbólicos (escrito) frente a los perceptuales. Para ello plantea 2 hipótesis a contrastar: 1) Los modelos de las categorías 4 y 6 del AIA de Amidon, Amidon y Rosenshine realizados en un laboratorio de CCTV dan unos resultados, en cuanto al grado de identificación y discriminación de los mismos conseguidos por alumnos profesores, superiores a los modelos de las mismas categorías realizados en un aula real por medio de CPTV, y ambos, CCTV y CPTV, son superiores a los modelos escritos. 2) La actitud de los profesores ante los modelos de esas categorías realizadas en un laboratorio por medio de CCTV es más positiva que su actitud ante los modelos de estas categorías realizados en un aula real por medio de CPTV. 117 alumnos profesores inscritos en los cursos del CAP, asignados aleatoriamente a los 6 grupos experimentales. Diseño experimental 2 x 3. Dos categorías: la número 4 en que el profesor formula preguntas, con 3 subcategorías, preguntas de hecho (h), convergentes (c) y divergentes (d) y la número 6 en que el profesor da direcciones con 2 subcategorías, direcciones cognitivas (c) y disciplinarias (d); 3 condiciones: laboratorio (l), aula (a) y escrito (e); en total 6 grupos experimentales. Variables dependientes: 1) El grado de identificación y discriminación de las subcategorías y, 2) Las actitudes de los alumnos profesores ante los modelos. Hojas-registro de subcategorías y escala de actitudes. Prueba de rango de Duncan. Medias y porcentajes. Se encontraron diferencias significativas entre el grupo 'l' y 'a' en la categoría número 4, también entre el grupo 'l' y las medias de 'e y a' de la subcategoría 4 'h', sin embargo, no aparecen diferencias significativas entre los 3 grupos para la subcategoría 4 'c'. En la categoría número 6 ha sido significativa la diferencia entre las medias de los grupos 'e y l', no siendo así entre los grupos 'l y e' y 'e y a'. En la subcategoría 6 'a' ha sido significativa la diferencia entre los grupos 'l' y los otros grupos. La diferencia entre los grupos 'l' y 'a' ha sido significativa, no siéndolo entre los grupos 'l y e' y 'e y a' dentro de la subcategoría 6 'd'. De los resultados anteriores se confirma la segunda pero no la primera hipótesis de la investigación, es decir, los profesores alumnos muestran una actitud más positiva hacia los modelos realizados por CCTV, mientras que los 3 modelos (l, a, e) son igual de eficaces para la identificación y discriminación de categorías.
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This study sought to investigate in vivo the vascular response at the proximal and distal edges of the second-generation ABSORB everolimus-eluting bioresorbable vascular scaffold (BVS).
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PhIP carcinogenesis is initiated by N(2)-hydroxylation, mediated by several cytochromes P450, including CYP1A1. However, the role of CYP1A1 in PhIP metabolic activation in vivo is unclear. In this study, Cyp1a1-null and wild-type (WT) mice were used to investigate the potential role of CYP1A1 in PhIP metabolic activation in vivo. PhIP N(2)-hydroxylation was actively catalyzed by lung homogenates of WT mice, at a rate of 14.9 +/- 5.0 pmol/min/g tissue, but < 1 pmol/min/g tissue in stomach and small intestine, and almost undetectable in mammary gland and colon. PhIP N(2)-hydroxylation catalyzed by lung homogenates of Cyp1a1-null mice was approximately 10-fold lower than that of WT mice. In contrast, PhIP N(2)-hydroxylation activity in lung homogenates of Cyp1a2-null versus WT mice was not decreased. Pretreatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) increased lung Cyp1a1 mRNA and lung homogenate PhIP N(2)-hydroxylase activity approximately 50-fold in WT mice, where the activity was substantially inhibited (70%) by monoclonal antibodies against CYP1A1. In vivo, 30 min after oral treatment with PhIP, PhIP levels in lung were similar to those in liver. After a single dose of 0.1 mg/kg [(14)C]PhIP, lung PhIP-DNA adduct levels in Cyp1a1-null mice, but not in Cyp1a2-null mice, were significantly lower (P=0.0028) than in WT mice. These results reveal that mouse lung has basal and inducible PhIP N(2)-hydroxylase activity predominantly catalyzed by CYP1A1. Because of the high inducibility of human CYP1A1, especially in cigarette smokers, the role of lung CYP1A1 in PhIP carcinogenesis should be considered.
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Although low-density lipoprotein (LDL) cholesterol is often normal in patients with type 2 diabetes mellitus, there is evidence for a reduced fractional catabolic rate and consequently an increased mean residence time (MRT), which can increase atherogenic risk. The dyslipidemia and insulin resistance of type 2 diabetes mellitus can be improved by aerobic exercise, but effects on LDL kinetics are unknown. The effect of 6-month supervised exercise on LDL apolipoprotein B kinetics was studied in a group of 17 patients with type 2 diabetes mellitus (mean age, 56.8 years; range, 38-68 years). Patients were randomized into a supervised group, who had a weekly training session, and an unsupervised group. LDL kinetics were measured with an infusion of 1-(13)C leucine at baseline in all groups and after 6 months of exercise in the patients. Eight body mass index-matched nondiabetic controls (mean age, 50.3 years; range, 40-67 years) were also studied at baseline only. At baseline, LDL MRT was significantly longer in the diabetic patients, whereas LDL production rate and fractional clearance rates were significantly lower than in controls. Percentage of glycated hemoglobin A(1c), body mass index, insulin sensitivity measured by the homeostasis model assessment, and very low-density lipoprotein triglyceride decreased (P < .02) in the supervised group, with no change in the unsupervised group. After 6 months, LDL cholesterol did not change in either the supervised or unsupervised group; but there was a significant change in LDL MRT between groups (P < .05) that correlated positively with very low-density lipoprotein triglyceride (r = 0.51, P < .04) and negatively with maximal oxygen uptake, a measure of fitness (r = -0.51, P = .035), in all patients. The LDL production and clearance rates did not change in either group. This study suggests that a supervised exercise program can reduce deleterious changes in LDL MRT.