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The common lanceheadBothrops jararacais widespread in the Atlantic Forest inBrazil. The species is known to show a marked sexual dimorphism pattern, with thefemale being larger than the male. However, most efforts in clarifying morphologicalvariation between the sexes are often focused on a single population. In this paper,we investigate how sexual dimorphism and ontogenetic trajectories vary among pop-ulations as well as the ontogenetic trajectories ofB. jararaca. We analyzed 211 spec-imens from a coastal and a highland population and measured 17 morphologicaltraits, including linear and meristic characteristics, and the analysis revealed a clearbut variable effect of sex and population. Females were larger than males in all eval-uated populations. Furthermore, females in the coastal population were generallysmaller than in the highland population but had significantly more scales. Widespreadspecies often experience differential environmental pressures even in terms of bioticand abiotic factors. We attribute the results found herein to specificities in prey avail-ability and climatic conditions which affect the ontogenetic pattern between the sexesand the populations, resulting in specific sexual dimorphism patterns.

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The sexual system of the symbiotic shrimp Thor amboinensis is described, along with observations on sex ratio and host-use pattern of different populations. We used a comprehensive approach to elucidate the previously unknown sexual system of this shrimp. Dissections, scanning electron microscopy, size-frequency distribution analysis, and laboratory observations demonstrated that T. amboinensis is a protandric hermaphrodite: shrimp first mature as males and change into females later in life. Thor amboinensis inhabited the large and structurally heterogeneous sea anemone Stichodactyla helianthus in large groups (up to 11 individuals) more frequently than expected by chance alone. Groups exhibited no particularly complex social structure and showed male-biased sex ratios more frequently than expected by chance alone. The adult sex ratio was male-biased in the four separate populations studied, one of them being thousands of kilometers apart from the others. This study supports predictions central to theories of resource monopolization and sex allocation. Dissections demonstrated that unusually large males were parasitized by an undescribed species of isopod (family Entoniscidae). Infestation rates were similarly low in both sexes (≈11%-12%). The available information suggests that T. amboinensis uses pure search promiscuity as a mating system. This hypothesis needs to be formally tested with mating behavior observations and field measurements on the movement pattern of both sexes of the species. Further detailed studies on the lifestyle and sexual system of all the species within this genus and the development of a molecular phylogeny are necessary to elucidate the evolutionary history of gender expression in the genus Thor.

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Se trata de un lactante de 16 meses de edad, desnutrido, que al ser internado presentaba rinofaringitis, palidez generalizada y edema. El motivo de consulta fue anorexia e irritabilidad. Durante la hospitalizacion presento tres crisis de anemia simultaneas con procesos infecciosos febriles del tracto respiratorio superior.En dichas oportunidades necesito transfusion de globulos rojos sedimentados. El tipo de anemia era normocitica hipocromica, con una reticulocitosis leve, hipersideremia y una medula osea con actividad eritropoyetica disminuida. Investigamos la causa y llegamos al diagnostico de anemia por deficit de la enzima glutation reductasa intra-eritrocitaria. Este deficit fue de caracter adquirido y secundario a la ingesta insuficiente de riboflavina. Las infecciones precipitaron las crisis de anemia. La terapia especifica con riboflavina resulto exitosa

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Se trata de un lactante de 16 meses de edad, desnutrido, que al ser internado presentaba rinofaringitis, palidez generalizada y edema. El motivo de consulta fue anorexia e irritabilidad. Durante la hospitalizacion presento tres crisis de anemia simultaneas con procesos infecciosos febriles del tracto respiratorio superior.En dichas oportunidades necesito transfusion de globulos rojos sedimentados. El tipo de anemia era normocitica hipocromica, con una reticulocitosis leve, hipersideremia y una medula osea con actividad eritropoyetica disminuida. Investigamos la causa y llegamos al diagnostico de anemia por deficit de la enzima glutation reductasa intra-eritrocitaria. Este deficit fue de caracter adquirido y secundario a la ingesta insuficiente de riboflavina. Las infecciones precipitaron las crisis de anemia. La terapia especifica con riboflavina resulto exitosa

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