Ultradian Rhythms
Mostrando 1-12 de 12 artigos, teses e dissertações.
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1. Ontogênese do ritmo de consumo de oxigênio em operárias de Melipona quadrifasciata (Hymenoptera; Meliponini): a influência da luz / Ontogenesis of respiratory rhythms in Melipona quadrifasciata workers: the influence of light
As operárias de Melipona quadrifasciata exercem diferentes funções na colônia, segundo sua faixa etária. No interior da colônia, os indivíduos mais jovens, nutrizes, ficam localizados na região mais interna e aproximam-se progressivamente das regiões periféricas à medida que envelhecem. Os indivíduos mais velhos, forrageiras, saem da colônia dia
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/04/2012
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2. Estudo da ontogênese dos ritmos biológicos em neonatos humanos e ratos. / Study of the ontogenesis of biological rhythms in newborns humans and rats.
Fatores ambientais podem modificar o desenvolvimento dos ritmos biológicos em neonatos, como já demonstrado em ratos. Neste contexto insere-se o estudo de recém-nascidos pré-termo mantidos em unidades de cuidado neonatal. Descrevemos neste trabalho a evolução da ritmicidade no ciclo vigília/sono, atividade/repouso, temperatura do punho e alimentação
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 04/08/2011
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3. COMPORTAMENTO DE PEQUENOS FELINOS NEOTROPICAIS EM CATIVEIRO
The lack of information concerning the small neotropical felids can be related to their predominant nocturnal activity, use of dense vegetation and hunting that threats natural populations. Therefore, research with captive animals may supply essential information for the development of effective conservation plans and strategies. The aim of this work was to
Publicado em: 2008
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4. Ontogenesis of respiratory rhythms in Melipona quadrifasciata adult workers (Hymenoptera, Apidae, Meliponini). / Variações ontogenéticas nos parâmetros do ritmo respiratório de operárias de Melipona quadrifasciata (Hymenoptera, Apidae, Meliponini).
The eusocial organization promotes a behavioural development of adult worker-bees, based on an age-related division of labour. Workers switch from tasks inside the hive to foraging and undergo a progressive transition from controlled environment of the hive to a diurnal exposure to the environment outside the hive. The coordination of queen and workers act
Publicado em: 2006
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5. Genes that control a temperature-compensated ultradian clock in Caenorhabditis elegans.
Substantial progress has been made in understanding the genetic basis of temperature-compensated circadian clocks. Ultradian rhythms, with a period shorter than 24 h, are at least as widespread as circadian rhythms. We have initiated genetic analysis of defecation behavior, which is controlled by an ultradian clock in Caenorhabditis elegans. The defecation m
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6. Secretory patterns of growth hormone in dogs: circannual, circadian, and ultradian rhythms
The objective was to characterize the circannual, circadian, and ultradian secretory patterns of growth hormone (GH) in intact crossbred and purebred dogs. In all experiments, blood samples were collected with minimal stress by direct peripheral venipuncture and GH was measured in plasma by a homologous radioimmunoassay. For circannual studies, samples were
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7. Ultradian Growth in Prochlorococcus spp.
Species of the widespread marine prokaryote Prochlorococcus exhibited ultradian growth (faster than 1 division per day) both in situ and in culture, even though cell division is strictly phased to the light-dark cycle. Under optimal conditions a second DNA replication and cell division closely followed, but did not overlap with, the first division. The timin
American Society for Microbiology.
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8. In situ localization of the per clock protein during development of Drosophila melanogaster.
The per locus influences biological rhythms in Drosophila melanogaster. In this study, per transcripts and proteins were localized in situ in pupae and adults. Earlier genetic studies have demonstrated that per expression is required in the brain for circadian locomotor activity rhythms and in the thorax for ultradian rhythmicity of the Drosophila courtship
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9. Ultradian oscillations in somatostatin and growth hormone-releasing hormone mRNAs in the brains of adult male rats.
In the adult male rat, growth hormone (GH) secretion is characterized by an ultradian rhythm generated by the rhythmic interplay of the stimulatory effects of GH-releasing hormone (GHRH) and the inhibitory effects of somatostatin (Ss). Although considerable evidence indicates that GHRH and Ss are secreted in reciprocal 3- to 4-hr rhythms, the mechanism under
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10. An ion channel of the degenerin/epithelial sodium channel superfamily controls the defecation rhythm in Caenorhabditis elegans
Ultradian rhythms are widespread phenomena found in various biological organisms. A typical example is the defecation behavior of the nematode Caenorhabditis elegans, which repeats at about 45-sec intervals. To elucidate the mechanism, we studied flr-1 mutants, which show very short defecation cycle periods. The mutations also affect some food-related functi
The National Academy of Sciences.
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11. FLR-4, a Novel Serine/Threonine Protein Kinase, Regulates Defecation Rhythm in Caenorhabditis elegans
The defecation behavior of the nematode Caenorhabditis elegans is controlled by a 45-s ultradian rhythm. An essential component of the clock that regulates the rhythm is the inositol trisphosphate receptor in the intestine, but other components remain to be discovered. Here, we show that the flr-4 gene, whose mutants exhibit very short defecation cycle perio
The American Society for Cell Biology.
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12. Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man.
Studies in man have shown that the episodic release of growth hormone (GH) is infrequent and erratic, and unlike that in the rat does not appear to have discernible ultradian periodicities. However, these observations in nonfasted subjects may be invalid since mixed nutrients have unpredictable effects on GH release. Moreover, in the fed state basal GH level