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1.
Plant Biol (Stuttg) ; 21(6): 1016-1023, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31237057

RESUMO

The presence of glandular appendages in the anthers is a rare condition in angiosperms. In Leguminosae it occurs in species of the Mimosoid clade and in early-branching clades of papilionoids such as Dipterygeae. In Dipterygeae such appendages surprisingly exhibit a secretory cavity instead of secretory emergences as is the case for the Mimosoid clade. Thus, the objective of this study was to elucidate the function of anther glands in Dipteryx alata and Pterodon pubescens, species in the Dipterygeae clade that exhibit a pollen release mechanism that is intermediate between the explosive and valvular types. Flower buds and flowers were processed for surface, anatomical, histochemical and ultrastructural analyses. Anther glands consist of a cavity secreting sticky substances (oleoresins and polysaccharides) that play a key role during the flower's lifespan by aggregating pollen grains and attaching them to the floral visitor's body. Other floral features that are important for understanding the pollen release mechanism that is intermediate between the valvular and the explosive types are: (i) keel petals intertwined with tector trichomes; (ii) glandular appendages in the abaxial and lateral sepals and in petals composed of secretory ducts; and (iii) a continuous secretion process of the anther glands followed by an asynchronous dehiscence of anthers. The well-adapted papilionoid flag blossom with anther glands and keel petals intertwined with trichomes provided the foundation for a successful canalisation toward a pollen release mechanism intermediate between the explosive and valvular types inside early-branching papilionoids.


Assuntos
Fabaceae/fisiologia , Flores/fisiologia , Polinização/fisiologia , Dipteryx/metabolismo , Dipteryx/fisiologia , Fabaceae/metabolismo , Flores/metabolismo , Extratos Vegetais/metabolismo , Polissacarídeos/metabolismo
2.
Rev Panam Salud Publica ; 9(5): 315-9, 2001 May.
Artigo em Português | MEDLINE | ID: mdl-11476021

RESUMO

OBJECTIVE: To describe the reference values for lead in blood in an urban population in the city of Londrina, in the state of Paraná, Brazil. MATERIALS AND METHODS: The reference population was composed of 520 adult volunteers who were assessed from November 1994 to December 1996. Exclusion criteria were: occupational exposure to lead, exposure through personal habits or practices, smoking more than 10 cigarettes per day, and living near industrial plants or other places that use lead in their production processes. Also excluded were individuals with abnormal clinical or laboratory results or with chronic diseases or cardiovascular disorders. Lead blood levels were determined using air-acetylene flame atomic absorption spectrophotometry. The detectable limit was 1.23 micrograms/dL. After the analyses of lead in blood, the following values were determined: minimum value, first quartile, median, third quartile, and maximum value; geometric mean; 95% confidence interval; experimental interval; and reference value. RESULTS: The reference values for lead in blood ranged from 1.20 micrograms/dL to 13.72 micrograms/dL. The geometric mean was 5.5 micrograms/dL. CONCLUSIONS: In general, the values found in this study are lower than those that have been reported for other countries. Additional data should be gathered from Brazilian populations living in more-industrialized areas.


Assuntos
Chumbo/sangue , Adulto , Brasil , Feminino , Humanos , Masculino , Valores de Referência , População Urbana
3.
Rev Saude Publica ; 31(2): 144-8, 1997 04.
Artigo em Português | MEDLINE | ID: mdl-9497561

RESUMO

INTRODUCTION: The lead reference values for blood used in Brazil come from studies conducted in other countries, where socioeconomic, clinical, nutritional and occupational conditions are significantly different. In order to guarantee an accurate biomonitoring of the population which is occupationally exposed to lead, a major health concern of the studied community, reference values for individuals who are not occupationally exposed and who live in the southern region of the city were established. MATERIAL AND METHOD: The sample was composed of 206 subjects of at least 15 years of age. Various strategies were employed to assure good-quality sampling. Subjects who presented values outside clinical or laboratory norms were excluded, as well as those whose specific activities might interfere with the results. RESULTS: Lead reference values for blood were found to be from 2.40 to 16.6 micrograms.dL-1, obtained by the interval x +/- 2s (where x is the mean and s is the standard deviation form observed values) and the median was 7.9 micrograms.dL-1.


Assuntos
Chumbo/sangue , População Urbana , Adolescente , Adulto , Brasil , Feminino , Humanos , Masculino , Valores de Referência
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