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1.
Plant Biol (Stuttg) ; 18(1): 15-25, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25678071

RESUMO

Relationships among floral biology, floral micromorphology and pollinator behaviour in bird-pollinated orchids are important issues to understand the evolution of the huge flower diversity within Orchidaceae. We aimed to investigate floral mechanisms underlying the interaction with pollinators in two hummingbird-pollinated orchids occurring in the Atlantic forest. We assessed floral biology, nectar traits, nectary and column micromorphologies, breeding systems and pollinators. In both species, nectar is secreted by lip calli through spaces between the medial lamellar surfaces of epidermal cells. Such a form of floral nectar secretion has not been previously described. Both species present functional protandry and are self-compatible yet pollinator-dependent. Fruit set in hand-pollination experiments was more than twice that under natural conditions, evidencing pollen limitation. The absence of fruit set in interspecific crosses suggests the existence of post-pollination barriers between these sympatric co-flowering species. In Elleanthus brasiliensis, fruits resulting from cross-pollination and natural conditions were heavier than those resulting from self-pollination, suggesting advantages to cross-pollination. Hummingbirds pollinated both species, which share at least one pollinator species. Species differences in floral morphologies led to distinct pollination mechanisms. In E. brasiliensis, attachment of pollinarium to the hummingbird bill occurs through a lever apparatus formed by an appendage in the column, another novelty to our knowledge of orchid pollination. In E. crinipes, pollinarium attachment occurs by simple contact with the bill during insertion into the flower tube, which fits tightly around it. The novelties described here illustrate the overlooked richness in ecology and morphophysiology in Orchidaceae.


Assuntos
Aves/fisiologia , Orchidaceae/fisiologia , Polinização/fisiologia , Adaptação Biológica , Animais , Biota , Brasil , Flores/anatomia & histologia , Flores/fisiologia , Frutas/fisiologia , Néctar de Plantas/química , Néctar de Plantas/fisiologia , Pólen/fisiologia , Especificidade da Espécie , Simpatria
2.
Braz J Med Biol Res ; 35(7): 837-42, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12131925

RESUMO

The Horne-Ostberg questionnaire partly covers some factors that may be important determinants of peak time and characterize patterns of behavior. We conducted a study for the evaluation of self-reported behavioral states (hunger sensation, availability for study, physical exercise, solving daily problems, and time preferences) as expressions of underlying cyclic activity. Three hundred and eighteen community subjects without history of medical, psychiatric, or sleep disorders were evaluated in a cross-sectional design. A self-report about daily highest level of activity was used to categorize individuals into morning, evening, and indifferently active. Time-related behavioral states were evaluated with 23 visual analog questions. The responses to most analogic questions were significantly different between morning and evening active subjects. Logistic regression analysis identified a group of behaviors more strongly associated with the self-reported activity pattern (common wake up time, highest subjective fatigue, as well as wake up, bedtime, exercise and study preferences). These findings suggested that the patterns of activity presented by normal adults were related to specific common behavioral characteristics that may contribute to peak time.


Assuntos
Nível de Alerta , Ritmo Circadiano/fisiologia , Adolescente , Adulto , Análise de Variância , Relógios Biológicos , Estudos Transversais , Exercício Físico/fisiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Sono , Inquéritos e Questionários
3.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;35(7): 837-842, July 2002. tab
Artigo em Inglês | LILACS | ID: lil-316737

RESUMO

The Horne-Östberg questionnaire partly covers some factors that may be important determinants of peak time and characterize patterns of behavior. We conducted a study for the evaluation of self-reported behavioral states (hunger sensation, availability for study, physical exercise, solving daily problems, and time preferences) as expressions of underlying cyclic activity. Three hundred and eighteen community subjects without history of medical, psychiatric, or sleep disorders were evaluated in a cross-sectional design. A self-report about daily highest level of activity was used to categorize individuals into morning, evening, and indifferently active. Time-related behavioral states were evaluated with 23 visual analog questions. The responses to most analogic questions were significantly different between morning and evening active subjects. Logistic regression analysis identified a group of behaviors more strongly associated with the self-reported activity pattern (common wake up time, highest subjective fatigue, as well as wake up, bedtime, exercise and study preferences). These findings suggested that the patterns of activity presented by normal adults were related to specific common behavioral characteristics that may contribute to peak time


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Nível de Alerta , Ritmo Circadiano , Análise de Variância , Relógios Biológicos , Estudos Transversais , Exercício Físico , Modelos Logísticos , Sono , Inquéritos e Questionários
4.
Arq Bras Cardiol ; 72(3): 363-86, 1999 Mar.
Artigo em Inglês, Português | MEDLINE | ID: mdl-10513047

RESUMO

Cardiopulmonary arrest is a medical emergency in which the lapse of time between event onset and the initiation of measures of basic and advanced support, as well as the correct care based on specific protocols for each clinical situation, constitute decisive factors for a successful therapy. Cardiopulmonary arrest care cannot be restricted to the hospital setting because of its fulminant nature. This necessitates the creation of new concepts, strategies and structures, such as the concept of life chain, cardiopulmonary resuscitation courses for professionals who work in emergency medical services, the automated external defibrillator, the implantable cardioverter-defibrillator, and mobile intensive care units, among others. New concepts, strategies and structures motivated by new advances have also modified the treatment and improved the results of cardiopulmonary resuscitation in the hospital setting. Among them, we can cite the concept of cerebral resuscitation, the application of the life chain, the creation of the universal life support algorithm, the adjust-ment of drug doses, new techniques--measure of the end-tidal carbon dioxide levels and of the coronary perfusion pressure--and new drugs under research.


Assuntos
Reanimação Cardiopulmonar/métodos , Humanos , Cuidados para Prolongar a Vida
5.
Arq. bras. cardiol ; Arq. bras. cardiol;69(6): 421-3, dez. 1997. ilus
Artigo em Português | LILACS | ID: lil-234376

RESUMO

Paciente com timoma e função sistólica normal do ventrículo esquerdo desenvolveu tamponamento cardíaco, revertido por pericardiocentese. Após quatro dias, foi submetida à exérese do tumor e, em aproximandamente uma semana da drenagem, apresentou disfunção sistólica aguda e grave do ventrículo esquerdo, que melhorou com terapia venosa, normalizando o quadro em três dias.


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Derrame Pericárdico/patologia , Disfunção Ventricular Esquerda/complicações , Drenagem , Cuidados Pós-Operatórios , Respiração Artificial
6.
Arq Bras Cardiol ; 69(6): 421-3, 1997 Dec.
Artigo em Português | MEDLINE | ID: mdl-9609015

RESUMO

A patient with a thymoma and initially normal ventricular systolic function developed cardiac tamponade, which was relieved by pericardiocentesis. After four days, the tumor was removed and, one week after the relief of tamponade, she developed severe left ventricular systolic dysfunction, that recovered in three days with venous therapy.


Assuntos
Tamponamento Cardíaco/etiologia , Drenagem/efeitos adversos , Sístole , Disfunção Ventricular Esquerda/etiologia , Doença Aguda , Idoso , Neoplasias da Mama/complicações , Feminino , Humanos , Timoma/complicações , Neoplasias do Timo/complicações
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