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1.
Planta ; 212(5-6): 684-91, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11346941

RESUMEN

A study was made of cambial activity, the localization of storage starch around the cambium, and the localization and occurrence of microtubules in cambial cells from dormancy to reactivation in locally heated (22-26 degrees C) stems of the evergreen conifer Abies sachalinensis. Heating induced localized reactivation of the cambium in the heated portions of the stem. Erect ray cambial cells resumed cell division 1 d prior to the reactivation of fusiform cambial cells and procumbent ray cambial cells. The re-initiation of the division of fusiform cambial cells occurred first on the phloem side. During the heat treatment, the amount of storage starch decreased in procumbent ray cambial cells and in the phloem parenchyma adjacent to the cambium but increased in fusiform cambial cells. Preprophase bands of microtubules, spindle microtubules and phragmoplast microtubules were observed both in erect ray cambial cells and in procumbent ray cambial cells. By contrast, no evidence of the presence of such preprophase bands of microtubules was detected in fusiform cambial cells. The results suggest that the localized heating of stems of evergreen conifers might provide a useful experimental model system for studies of the dynamics of cambial reactivation in intact trees.


Asunto(s)
Cycadopsida/fisiología , Meristema/fisiología , Cycadopsida/citología , Calor , Meristema/citología , Microtúbulos/fisiología , Microtúbulos/ultraestructura , Mitosis/fisiología , Modelos Biológicos , Orgánulos/metabolismo , Almidón/metabolismo , Árboles/citología , Árboles/fisiología , Tiempo (Meteorología)
2.
Percept Mot Skills ; 93(3): 785-96, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11806602

RESUMEN

Heart-rate variability in four normal and 30 mentally retarded children was investigated during nocturnal sleep. In four normal and 25 mentally retarded subjects, a high frequency component defined as spectral activity between 0.15 and 0.5 Hz was found in the compressed spectral array of the power spectra. A periodic change was seen in the high frequency component which corresponded precisely to the sleep cycle. However, four children with mental retardation did not show normally expected changes in the high frequency components specific to the sleep stages: a quantity of the high frequency component in only one sleep cycle (n=2; 6 mo. and 3 yr., 8 mo.), a decreased quantity and discontinuity of the high frequency component in only the second sleep cycle (n=1; 1 yr., 2 mo.), and no high frequency component in any sleep cycle (n=1; 3 mo.) These findings suggest that some mentally retarded children have an abnormal parasympathetic nervous activity.


Asunto(s)
Nivel de Alerta/fisiología , Frecuencia Cardíaca/fisiología , Discapacidad Intelectual/fisiopatología , Polisomnografía , Fases del Sueño/fisiología , Adolescente , Corteza Cerebral/fisiopatología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Sistema Nervioso Parasimpático/fisiopatología , Valores de Referencia , Sueño REM/fisiología
3.
Percept Mot Skills ; 84(3 Pt 1): 967-75, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9172211

RESUMEN

During passive and active listening tasks baseline respiratory sinus arrhythmia and heart-rate responses were studied of 18 children with Attention-Deficit Hyperactivity Disorder (ADHD) and 49 healthy school children. The experimental procedure included baseline recording (no task), a passive listening task, instructions, and both simple and discriminative active-listening tasks. ADHD subjects showed less respiratory sinus arrhythmia than normal children but were similarly responsive to tone stimuli.


Asunto(s)
Arritmia Sinusal/fisiopatología , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Atención/fisiología , Frecuencia Cardíaca/fisiología , Percepción de la Altura Tonal/fisiología , Estimulación Acústica , Arritmia Sinusal/diagnóstico , Arritmia Sinusal/psicología , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Trastorno por Déficit de Atención con Hiperactividad/psicología , Sistema Nervioso Autónomo/fisiopatología , Niño , Femenino , Humanos , Masculino , Psicoacústica , Valores de Referencia
4.
Percept Mot Skills ; 79(1 Pt 2): 403-10, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7808875

RESUMEN

Age differences in characteristics of the attention process of electrodermal activity during passive and active listening tasks were studied with 43 nursery and 49 primary school children and 38 university students. The procedure included baseline recording, a passive listening task, instruction, and an active listening task. Significant differences in skin conductance response (SCR) were found among the three age groups. The SCR became smaller for the groups of increasing ages only for the active listening task. As the trials progressed, there was a trend in the three age groups for decreasing SCR amplitude during the passive listening task.


Asunto(s)
Nivel de Alerta , Atención , Desarrollo Infantil , Respuesta Galvánica de la Piel , Percepción de la Altura Tonal , Adolescente , Adulto , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Masculino , Desempeño Psicomotor , Psicofísica
5.
Percept Mot Skills ; 78(2): 571-8, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8022683

RESUMEN

Various physical training programs have been devised to achieve greater physical fitness for handicapped children who otherwise exercise insufficiently. Such training may also facilitate socializing and play at school. Running exercises were conducted with 4 handicapped preschoolers and 3 age-matched normal preschoolers for 3 30-min. sessions per week for 11 weeks. Measures were seconds taken to run 25 meters and ratings of play behavior. Analysis showed that children who reluctantly joined the exercise made little progress in running. The quality of movement and play activities in nursery school and interactive behavior improved significantly for participants who also improved in running.


Asunto(s)
Atención , Educación de las Personas con Discapacidad Intelectual , Discapacidad Intelectual/rehabilitación , Juego e Implementos de Juego , Carrera/psicología , Preescolar , Femenino , Humanos , Discapacidad Intelectual/psicología , Masculino , Aptitud Física/psicología , Conducta Social
6.
Percept Mot Skills ; 77(1): 331-8, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8367260

RESUMEN

Electrodermal activity during passive and active listening tasks of 18 children with Attention-Deficit Hyperactivity Disorder (ADHD) and 49 healthy school children was studied. The procedure included baseline recording, a passive listening task, instructions, and both simple and discriminative active-listening tasks. ADHD subjects tended to exhibit lower arousal as indicated by the decrease in amplitude of the skin conductance response. Present findings confirm classical observation that ADHD children have shorter attention spans.


Asunto(s)
Estimulación Acústica , Trastorno por Déficit de Atención con Hiperactividad/psicología , Respuesta Galvánica de la Piel/fisiología , Adolescente , Trastorno por Déficit de Atención con Hiperactividad/complicaciones , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico , Percepción Auditiva/fisiología , Niño , Trastornos de la Conducta Infantil/complicaciones , Trastornos de la Conducta Infantil/diagnóstico , Femenino , Humanos , Masculino , Escalas de Valoración Psiquiátrica
7.
Cancer Lett ; 71(1-3): 57-60, 1993 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-8364900

RESUMEN

In order to discover the role in the promotion process of 5-lipoxygenase (5-LO), a key enzyme in the arachidonate cascade, the antipromoting effects of the 5-LO inhibiting 3-nitro-2,4,6-trihydroxybenzamide (NTB) derivatives were studied in a two-stage transformation assay system using BALB 3T3 cells. All compounds inhibited TPA-promoted transformation in a dose-dependent manner. Most of them achieved a 70-80% inhibition. Good correlations were observed between the inhibition of TPA-promoted transformation and that of 5-LO. These results indicate that 5-LO plays an important role in the promotion stage of the transformation of BALB 3T3 cells.


Asunto(s)
Transformación Celular Neoplásica , Ácidos Hidroxámicos/farmacología , Inhibidores de la Lipooxigenasa , Células 3T3/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Metilcolantreno , Ratones , Acetato de Tetradecanoilforbol
8.
Cancer Lett ; 68(1): 1-5, 1993 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8380755

RESUMEN

The inhibitory effects of two series of 3-nitrophloroglucinecarboxylic acid derivatives, 3-nitro-2,4,6-trihydroxythiobenzamides (II) and 3-nitro-phloroglucinecarboxylates (III), on Epstein-Barr virus early antigen (EBV-EA) induction were examined using Raji cells. Some of them strongly inhibited the induction, N-nonyl and O-decyl derivatives being the most potent inhibitors among the thioamides and esters, respectively. These results suggest the possibility that these two 3-nitrophloroglucinecarboxylic acid derivatives may be listed as novel inhibitors of tumor promotion.


Asunto(s)
Antígenos Virales/efectos de los fármacos , Herpesvirus Humano 4/efectos de los fármacos , Floroglucinol/análogos & derivados , Antígenos Virales/biosíntesis , Herpesvirus Humano 4/inmunología , Floroglucinol/farmacología , Relación Estructura-Actividad
9.
Percept Mot Skills ; 75(1): 35-43, 1992 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1528690

RESUMEN

During passive and active listening tasks electrodermal activity of 49 healthy school children was studied. The procedure included baseline recording, a passive listening task, instructions, and simple and discriminative active-listening tasks. On the passive task from Trials 1 to 10, habituation of the amplitude of the skin conductance response (SCR) occurred. Habituation of SCR amplitude did not occur during the active tasks. The children seemed to pay more attention during the active tasks than during the passive task, since the need to press the key is apt to require and may even increase general attention. As for temporal variables of SCR, the frequency of spontaneous SCRs showed a significant negative correlation with SCR latency and rise time. Reaction time exhibited a significant negative correlation with age. An increase in reaction time was found during the discriminative active-listening task over that for the simple active-listening task during the course of 10 trials. The younger children (6-8 yr.) seemed to require longer to pay attention than the older ones (10-12 yr.). Children seemed to pay more attention during the discriminative than during the simple active-listening task, since the need to press the key for discrimination should require and is likely to increase general attention.


Asunto(s)
Nivel de Alerta , Atención , Percepción Auditiva , Respuesta Galvánica de la Piel , Niño , Desarrollo Infantil , Femenino , Habituación Psicofisiológica , Humanos , Masculino , Desempeño Psicomotor
10.
Cancer Lett ; 59(2): 83-8, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1653108

RESUMEN

Inhibitory effects of a series of 3-nitro-2,4,6-trihydroxybenzamides on Epstein-Barr virus early antigen (EBV-EA) induction were examined using Raji cells. Some of the tested compounds showed highly inhibitory activity, the N-octyl amide derivative being the most active among them. These results suggest the possibility that 3-nitro-2,4,6-trihydroxybenzamides might be listed as novel inhibitors of tumor promotion.


Asunto(s)
Antígenos Virales/biosíntesis , Herpesvirus Humano 4/efectos de los fármacos , Floroglucinol/análogos & derivados , Herpesvirus Humano 4/inmunología , Floroglucinol/química , Floroglucinol/farmacología , Relación Estructura-Actividad
11.
Percept Mot Skills ; 72(3 Pt 2): 1115-24, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1961660

RESUMEN

Temporal variation of electrodermal activity during passive and active listening tasks of 43 healthy preschool children was studied. The procedure included the baseline recording, a passive listening task, instruction, and an active listening task. The frequency of spontaneous skin-conductance responses (SCRs) showed a significant negative correlation with SCR latency and rise time. Mean SCR amplitude, moreover, displayed a significant negative correlation with the SCR latency and rise time. Reaction time exhibited a significant negative correlation with age. A decrease in the SCR latency was noted during the active listening task below that for the passive listening task over 10 trials. The children seemed to pay more attention as SCR latency and rise time decreased, and the younger children seemed to pay attention later than the older ones. Children seemed to pay more attention during the active than during the passive listening tasks, since the need to press the key should require and perhaps increase general attention.


Asunto(s)
Atención/fisiología , Percepción Auditiva/fisiología , Respuesta Galvánica de la Piel/fisiología , Factores de Edad , Desarrollo Infantil , Preescolar , Habituación Psicofisiológica/fisiología , Humanos , Tiempo de Reacción/fisiología , Análisis y Desempeño de Tareas , Factores de Tiempo
12.
Percept Mot Skills ; 70(1): 207-15, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2326118

RESUMEN

Electrodermal activity during passive and active listening tasks of 43 healthy preschool children (aged 4 yr., 8 mo. to 6 yr., 5 mo.) was studied. The procedure included the following phases: baseline recording (3 min.), a passive listening task, instructions, and an active listening task. An increase in mean amplitude of skin conductance response (SCR) was found during the active listening task over the level for the passive listening task over 10 trials. On the passive listening task from Trial 1 to Trial 10, habituation of mean SCR amplitude occurred. The younger children, moreover, exhibited significantly greater habituation than the older children. Habituation of mean SCR amplitude did not occur during the active listening task. No significant difference was found in mean SCR amplitude during the active listening task for the two age groups. The children seemed to pay more attention during the active listening task than during the passive listening task. The younger children, moreover, are believed to have shorter attention spans.


Asunto(s)
Nivel de Alerta , Atención , Percepción de la Altura Tonal , Desempeño Psicomotor , Niño , Preescolar , Femenino , Respuesta Galvánica de la Piel , Humanos , Masculino
13.
Percept Mot Skills ; 70(1): 235-42, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2326123

RESUMEN

Electrodermal activity during passive and active listening tasks for 4 hyperactive (from 3 yr., 9 mo. to 6 yr., 2 mo.) and 43 healthy preschool children (from 4 yr., 8 mo. to 6 yr., 5 mo.) was studied. The procedure consisted of the following phases: baseline recordings (3 min.), a passive listening task, instructions, and an active listening task. The hyperactive subjects tended to exhibit lower levels of arousal, as indicated by the frequency of spontaneous responses, and more marked habituation with repeated stimuli. Also, they tended not to show the increased responsivity expected when attention is active rather than passive. Hyperactive preschool children, moreover, are believed to have shorter attention spans.


Asunto(s)
Nivel de Alerta , Trastorno por Déficit de Atención con Hiperactividad/psicología , Atención , Percepción del Habla , Niño , Preescolar , Femenino , Respuesta Galvánica de la Piel , Humanos , Masculino , Desempeño Psicomotor
14.
J Surg Res ; 45(3): 314-9, 1988 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3411955

RESUMEN

In the present study, reticuloendothelial system (RES) phagocytic function of rats with partial hepatectomy or experimentally induced liver cirrhosis was investigated by determining the phagocytic index, the opsonic index, and uptake rate in liver, spleen, and lung of a 51Cr-labeled endotoxin-injected rat. In both the partially hepatectomized and the cirrhotic rats, all three indicators varied markedly according to the elapsed period since liver injury. The changes in RES phagocytic function were classified into three different phases: compromised, compensatory, and enhanced. The compromised phase, consisting of a decrease in the phagocytic index, was observed during the first 24 hr after 67% hepatectomy and in advanced liver cirrhosis. This represented the failure of RES phagocytic function. The compensatory phase, in which the phagocytic index was maintained at nearly normal levels mainly by a compensatory enhancement in the opsonic index, was seen during the first to second postoperative day and in moderate liver cirrhosis. The enhanced phase, with a high phagocytic index, was observed from Day 4 to approximately Day 14 after surgery, and in the cases of mild liver damage. In the compromised and compensatory phases, the liver uptake rate was significantly decreased compared with the control. However, the uptake in the spleen and lung were markedly increased. In conclusion, the phagocytic function of the RES was significantly affected to a degree which changed with the extent of liver damage.


Asunto(s)
Hepatopatías/inmunología , Sistema Mononuclear Fagocítico/fisiopatología , Fagocitosis , Animales , Hepatectomía , Hígado/inmunología , Cirrosis Hepática Experimental/inmunología , Pulmón/inmunología , Masculino , Proteínas Opsoninas/análisis , Ratas , Ratas Endogámicas , Bazo/inmunología
15.
Artículo en Inglés | MEDLINE | ID: mdl-2439277

RESUMEN

Skin potential responses (SPRs) of 89 mentally retarded children were studied during their nocturnal sleep. Forty-three out of the 89 subjects showed more SPRs (type A) during NREM sleep than in REM sleep. The opposite was observed in 10 cases (type C), and 4 had evenly distributed SPRs during both sleep phases (type B). The remaining 32 subjects had mixed types AB (n = 19), AC (n = 6) or BC (n = 7). Types B and C (including the mixed type) were observed more frequently for subjects with low developmental quotient (DQ) and abnormal clinical EEGs than for those with high DQ and normal clinical EEGs. Since it has been well established that normal subjects of 3 months and over exhibit exclusively type A, SPRs may be used as an additional tool for the diagnostic assessment of mental retardation in early infancy.


Asunto(s)
Discapacidades del Desarrollo/complicaciones , Respuesta Galvánica de la Piel/fisiología , Discapacidad Intelectual/fisiopatología , Sueño/fisiología , Adolescente , Niño , Preescolar , Discapacidades del Desarrollo/fisiopatología , Electroencefalografía , Femenino , Humanos , Lactante , Discapacidad Intelectual/complicaciones , Masculino
16.
Electroencephalogr Clin Neurophysiol ; 66(6): 512-4, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2438116

RESUMEN

REM sleep latency observed in 61 mentally retarded infants (4-13 months of age) was studied throughout nocturnal sleep. Mentally retarded infants revealed a J distribution of short (less than 8 min) and long (more than 8 min) REM sleep latencies. This feature of distribution was similar to that obtained by other authors from normal infants under 3 months of age. REM sleep latency did not depend on the duration of prior wakefulness. Long REM sleep latencies were no more often preceded by long episodes of wakefulness than were short REM sleep latencies. No correlation was found between REM sleep latency and age, developmental quotient or daytime clinical EEG abnormalities.


Asunto(s)
Discapacidad Intelectual/fisiopatología , Sueño REM/fisiología , Envejecimiento/fisiología , Humanos , Lactante , Tiempo de Reacción/fisiología , Vigilia/fisiología
17.
Pediatr Neurosci ; 13(1): 9-12, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3684816

RESUMEN

The correlation between the delta and spindle components in compressed spectral array in 96 mentally retarded children (from 3 months to 12 years of age) was studied throughout nocturnal sleep. In 57 (59.4%, group A) of 96 subjects, periodic changes of delta and spindle rhythm powers were noted in sleep EEG. In 29 subjects (30.2% group B), delta but not spindle rhythm powers were found, and in the remaining 10 subjects (10.4%, group C) neither delta nor spindle rhythm powers were found throughout nocturnal sleep. A significant increase in abnormal clinical EEG was found in groups B and C as compared with group A. A significant decrease in the developmental quotient (DQ) was found in groups B and C as compared with group A. A significant decrease in DQ was also found in group C as compared with group B.


Asunto(s)
Electroencefalografía , Discapacidad Intelectual/fisiopatología , Sueño/fisiología , Niño , Desarrollo Infantil , Preescolar , Ritmo Delta , Femenino , Humanos , Lactante , Masculino
18.
Electroencephalogr Clin Neurophysiol ; 64(6): 493-500, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2430771

RESUMEN

The correlations between the delta and spindle components in compressed spectral array in 21 mentally retarded children with cerebral palsy (CP) (from 4 months to 5 years of age) and 32 reference mentally retarded children of no abnormality with the exception of psychomotor retardation (from 4 months to 12 years of age) were studied throughout nocturnal sleep. In 11 (52%) out of 21 CP cases and 27 (84%) out of 32 reference cases, periodic changes of delta and spindle rhythm powers were noted in sleep EEG (group A). In 5 (24%) other cases in CP and 5 (16%) reference cases delta but not spindle rhythm powers were found (group B), and in the remaining 5 (24%) CP cases neither delta nor spindle rhythm powers were found throughout nocturnal sleep (groups C). A significant decrease in the developmental quotient (DQ) was found in group C as compared with group A in both CP and reference cases. Moreover, a significant decrease in DQ was also found in group B as compared with group A of reference cases.


Asunto(s)
Parálisis Cerebral/fisiopatología , Electroencefalografía , Fases del Sueño/fisiología , Preescolar , Ritmo Delta , Femenino , Análisis de Fourier , Humanos , Lactante , Discapacidad Intelectual/fisiopatología , Masculino
19.
Clin Electroencephalogr ; 17(3): 152-7, 1986 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3742830

RESUMEN

The correlation between the delta and spindle components in compressed spectral array in 18 infants with congenital cerebral malformation (from 4 months to 4 years of age) was studied throughout nocturnal sleep. In 7 (39%, Group A) out of 18 subjects, periodic changes of delta and spindle rhythm powers were noted in the sleep EEG. In 5 subjects (28%, Group B), delta but not spindle rhythm powers were found, and in the remaining 6 subjects (33%, Group C) neither delta nor spindle rhythm powers were found throughout nocturnal sleep. A significant decrease in the developmental quotient was found in group C as compared with group A.


Asunto(s)
Encéfalo/anomalías , Electroencefalografía , Sueño/fisiología , Preescolar , Ritmo Delta , Femenino , Humanos , Lactante , Masculino
20.
Clin Electroencephalogr ; 17(2): 92-104, 1986 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3731502

RESUMEN

Sleep EEG patterns in 17 infants with cerebral malformations (4 months to 4 years of age) were studied throughout nocturnal sleep and the following results were obtained. Seven cases evidenced normal sleep/wakefulness EEG patterns that could be classified into 6 stages. Ten cases showed abnormal sleep EEG patterns as follows: absence of sleep spindles (n = 7) which included cases of absence of EEG patterns characteristic of wakefulness, NREM sleep and REM sleep (n = 5), no characteristic EEG patterns of stages 1-4 (n = 1) and stages W, 1, 2 and REM (n = 1) and the remaining cases with absence of spindles (n = 1), and spindles with an extremely low incidence (n = 2). Short sleep and long awaking times, and no delta rhythmicity during the night, were noted in 5 out of 17 subjects. A significant decrease of DQ was found in subjects with indistinguishable stages including stages W, 1, 2 and REM, as compared with those patients whose stages were all distinguishable.


Asunto(s)
Encéfalo/anomalías , Electroencefalografía , Sueño/fisiología , Agenesia del Cuerpo Calloso , Malformación de Arnold-Chiari/fisiopatología , Corteza Cerebral/anomalías , Preescolar , Femenino , Humanos , Hidranencefalia/fisiopatología , Lactante , Masculino , Microcefalia/fisiopatología , Fases del Sueño/fisiología
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