645 resultados para racial identity


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The Richieri-Costa-Pereira syndrome is a rare autosomal recessive disorder characterized by short stature, Robin sequence, cleft mandible, pre/postaxial anomalies and clubfoot. of 15 families reported with this disorder 14 are from Brazil suggesting a founder effect. We studied 15 families using identity-by-descent as a hypothesis to attempt gene localization We have examined through linkage analysis 497 polymorphicmarkers and also performed direct sequencing of exons for 10 candidate genes selected on the basis of their expression in the developing mandible and limb. No evidence for allele sharing at any locus tested or mutations in candidate genes was found. Additional higher resolution mapping, new families and other candidate genes might improve future chances of gene identification. (C) 2003 Wiley-Liss, Inc.

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Com o objetivo de avaliar a variabilidade genética e as relações de afinidade entre dezenove populações de oito raças de milho (Zea mays L.) - as comerciais antigas Cateto Sulino, Cateto Sulino Grosso, Cateto Nortista e Canario de Ocho, e as raças indígenas Moroti, Lenha, Entrelaçado e Caingang - analisaram-se os seguintes sistemas enzimáticos: glutamato oxalacetato transaminase (GOT), esterase (EST) e malato desidrogenase (MDH). Observou-se maior semelhança entre as raças pertencentes a um mesmo grupo, mas as populações analisadas não se agruparam de acordo com as raças, classificadas anteriormente segundo caracteres morfológicos. Os sistemas enzimáticos utilizados não permitiram a caracterização individual de cada uma das raças analisadas. As indígenas apresentaram maior variabilidade do que as comerciais antigas quanto ao número de alelos por loco e à porcentagem de locos polimórficos.

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The identification of the lebranche mullet in the western south Atlantic has long been problematical. In most recent works either Mugil liza Valenciennes and M. platanus Gunther, 1880 or M. liza and M. cephalus Linnaeus, 1758 were recognized from the region and more rarely the occurrence of only one species has been proposed but without sufficient morphological, biochemical or molecular data to allow the designation of the taxonomically appropriate name. Analysis of meristic and morphometric data taken from samples collected from Venezuela to Argentina, clearly indicates that there is only one species of lebranche mullet in the Caribbean Sea region and the Atlantic coast of South America and that Mugil liza is the appropriate name. The comparison of the combined data from all the samples of M. liza with the data taken from one sample of M. cephalus that originated in the Mediterranean, the possible locality from which type specimens were collected (Eschmeyer and Fricke, 2009), revealed significant differences indicating that they are different species. It is also suggested that individuals from the western north Atlantic identified as M. cephalus might represent a population of M. liza in this region.

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Recent field work in Atlantic Rain Forest patches in the southern region of the State of Bahia, Brazil, resulted in the discovery of some populations of an unidentified species of the Scinax catharinae group. An extensive literature review, along with the examination of specimens and distribution patterns of all known species of this group, showed that Hyla strigilata Spix, 1824, a long confused species with lost type material, is an available name for the specimens from Bahia. In order to clarify the taxonomic problems surrounding this taxon, the nomenclatural history of Hyla strigilata is reviewed and a neotype is designated, described, and figured. The association of this name to extant populations from southern Bahia and its consequent stabilization is considered important since it is the type species of the genus Ololygon, a name available for the clade of Scinax catharinae. Data on habits, habitat, and geographic distribution are also presented.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Knowledge of structural and physiological differences among the prostatic lobes (PL) is the basis for development of experimental studies in traditional laboratory rodents. Although Mongolian gerbil reproductive organs have been increasingly investigated, its prostate structure is far from being properly known, and investigations of this organ focused on the ventral lobe (VL). Thus, the present study provides a thorough morphological description of prostatic complex in the male adult gerbil on the basis of topographic, histological, and ultrastructural analysis and ductal branching. Like other rodents, four pairs of PL were observed. However, in contrast to the rat and mouse, the VL is the least voluminous component and the dorsolateral lobe (DLL) is the most prominent and spatially isolated from remaining PL. The occurrence of a dorsal lobe (DL), hidden between bladder and insertion of seminal vesicles, has not been mentioned in previous reports with Mongolian gerbil. Collagenase digestion followed by microdissection revealed that, except for DL, which has a tubularacinar organization, all PL exhibit tubular organization and variable ductal branching. Distinct histological and ultrastructural features such as secretory epithelium, aspect of luminal secretion and stromal organization are reported for each PL and are confirmed by morphometric and stereological methods. Histological sections showed at least three intralobar segments in VL and DL. Ultrastructural analysis evidenced that, although luminal epithelial cells of PL share typical features of exocrine secretory cells, there are striking lobe phenotypical variations. Both merocrine and apocrine pathways are observed in variable rates in all PL, with the predominance of the former in the DLL and the latter in the CG. The morphological observations presented herein point to distinct structural identities for each PL, which probably reflects,specific functional compromise of seminal fluid secretion. These data also point to the gerbil as a good model for investigations concerning the regulation of prostate development and homeostasis, mainly with regard to the dorsal and dorsolateral PL.

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The feather mite Pterodectes ralliculae Atyeo and Gaud, 1977 (Proctophyllodidae: Pterodectinae) is the only proctophyllodid known from rallids (Gruiformes, Rallidae). Based on re-examination of the type material, this mite species is redescribed and transferred to the genus Montesauria Oudemans, 1905, Montesauria ralliculae (Atyeo and Gaud, 1977) comb. nov. This redescription brings details of structures missed in the original description: in both sexes, vertical setae ve are present, setae mG on genu II, gT on tibia II and wa on tarsi I and II are present; in males, the rudimentary epimeral sclerites rEpIIa are present and the female is illustrated for the first time. The transfer of P. ralliculae to Montesauria was also supported by the preliminary phylogenetic hypothesis recently proposed for the subfamily Pterodectinae.

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In a covariant gauge we implicitly assume that the Green's function propagates information from one point of the space-time to another, so that the Green's function is responsible for the dynamics of the relativistic particle. In the light front form one would naively expect, that this feature would be preserved. In this manner, the fermionic field propagator can be split into a propagating piece and a non-propagating (contact) term. Since the latter (contact) one does not propagate information; and therefore, supposedly can be discarded with no harm to the field dynamics we wanted to know what would be the impact of dropping it off. To do that, we investigated its role in the Ward identity in the light front. Here we use the terminology Ward identity to identify the limiting case of photon's zero momentum transfer in the vertex from the more general Ward-Takahashi identity with nonzero momentum transfer.

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Objectives: the purpose of this study was to evaluate the correlation between central incisor form and face form in 4 racial groups and to investigate if there was agreement among experts in categorizing the central incisor forms. Method and Materials: A total of 160 subjects (40 whites, 40 mulattos, 40 blacks, and 40 Asians) ranging from 18 to 33 years of age were selected. Digital photographic records were made, 1 full-face and 1 intraoral view of the maxillary right central incisor. The outline tracings of the tooth and face images were obtained using Adobe Photoshop 5.0 software. The outline tracings were printed in distinct transparencies, and 3 prosthodontists determined if there was correspondence between the tooth and the face forms by superimposition of the transparencies. If there was disagreement among the prosthodontists' evaluations, the prevalent decision was considered. The experts also classified the central incisor forms into square, ovoid, tapering, or combination at 2 different sessions. At the first session, no instructions were given. At the second session, the prosthodontists were instructed to follow Williams' method of classification. Results: A correspondence between tooth and face forms was found in 23.75% of all cases. Agreement on the tooth form classifications among the prosthodontists occurred in 30.62% of all cases at the first session and 24.37% at the second session. Conclusion: There is not a highly defined correlation between central incisor form and face form in any racial group studied. In addition, the experts were not in fair agreement in categorizing tooth forms.

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OBJECTIVES: This paper was meant to analyse distribution of HbS carriers in Brazil, comprising its regional prevalence and the relationship with racial settlement and age groups. MATERIAL AND METHODS: 67,667 blood samples from 48 Brazilian towns were analysed from 1976 to 1988. Such samples were classified as Caucasoid and Negroid. The diagnosis was defined by means of qualitative electrophoresis in alkaline and acid pH, quantification of haemoglobin fractions, cytological studies and some cases were confirmed after examination of the parents. RESULTS: The study of those 67,667 samples allowed us to detect 1,492 HbS carriers (2.2%). That frequency is higher among Negroids (5.16%) than among Caucasoids (1.22%): Z = 22.1397 (Zcritical; 0.05 = 1.9600). Taking the HbS carrier distribution into consideration, we noticed that it is relatively homogeneous among Negroids and higher than 5% in 9 out of the 16 areas involved in the study. By classifying the age group of the areas in the general sample and by comparing the proportions, we found out that there are significant differences (chi 2 = 50.88; chi 2 critical; 0.05; 5 gl = 11.070). CONCLUSIONS: Sickle-cell anaemia diseases play an important role among the pathologies found in several countries, including Brazil. This paper shows that the carriers prevalence varies in the several areas under study and is higher among Negroids in almost all of them. The decreasing frequency occurring from North to South in the general samples and among Caucasoids may be assigned to the contribution of the Negroes in the interracial crossing, particularly in the Northeast.

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The correspondence between morphometric and isozymic geographic variation patterns of Africanized honey bees in Brazil was analyzed. Morphometric data consisted of mean vectors of 19 wing traits measured in 42 local populations distributed throughout the country. Isozymic data refer to allelic frequencies of malate dehydrogenase (MDH), and were obtained from Lobo and Krieger. The two data sets were analyzed through canonical trend surface, principal components and spatial autocorrelation analyses, and showed north-south dines, demonstrating that Africanized honey bees in southern and southeastern Brazil are more similar to European honey bees than those found in northern and northeastern regions. Also, the morphometric variation is within the limits established by the racial admixture model, considering the expected values of Africanized honey bee fore wing length (WL) in southern and northeastern regions of Brazil, estimated by combining average values of WL in the three main subspecies involved in the Africanization process (Apis mellifera scutellata, A. m. ligustica and A. m. mellifera) with racial admixture coefficients.

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Purpose: To determine whether intercommissural width is a reliable guide for the selection of maxillary denture teeth width. Materials and Methods: Casts were made of 160 subjects from 4 different racial groups. Locations of intercommissural width landmarks (the corners of the mouth) were made on the subjects and transferred to the casts. The distances between the corners of the mouth and the distal of the canines were measured on the casts and compared. Results: A weak correlation was found between the distal of the canines and the distance between the corners of the mouth in the 4 racial groups. Conclusion: The use of the corners of the mouth for the selection of artificial teeth is generally inaccurate.

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Purpose: Selecting artificial teeth for edentulous patients is difficult when pre-extraction records are not available. Various guidelines have been suggested for determining the width of the maxillary anterior denture teeth. This study was undertaken to evaluate the use of the nasal width as a guide for the selection of proper width maxillary anterior denture teeth in four racial groups of the Brazilian population. Materials and Methods: One hundred and sixty subjects (40 Whites, 40 Mulattos, 40 Blacks, and 40 Asians) were selected. Using a sliding caliper, the nasal width and the intercanine distance were measured. The Pearson product-moment correlation coefficient was used to determine the relationship between the above measurements. A prediction was made of the percentage of subjects of the White, Mulatto, Black, and Asian populations in which the selection error due to the clinical application of the method of the nasal width would be within 0 to 2 mm, within 2 to 4 mm, and greater than 4 mm. Results: The four racial groups showed a weak correlation between the intercanine distance and the nasal width. In 39.7% of the White, 55.7% of the Mulatto, 81.9% of the Black, and 48.2% of the Asian populations, errors greater than 4 mm would be present with the use of the nasal width. Conclusions: The correlation found between the intercanine distance and the nasal width was not high enough to be used as a predictive factor. The relationship between natural tooth width and artificial tooth width as predicted by the nasal width showed that the nasal width method is not accurate for all the studied groups. Copyright © 2006 by The American College of Prosthodontists.