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571.
The Y chromosome gene SRY plays an important role in normal male sexual development and is thought to be the testis-determining
factor. We describe a familial nonsense mutation in SRY, shared by two XY sisters with complete gonadal dysgenesis and, in
a mosaic manner, by their father. This mutation, consisting of a C to T transition in position 1 of codon 97 of SRY, results
in a truncated peptide with an incomplete DNA-binding domain. The mutation is also present in the father of the two cases,
but a portion of wild-type SRY also remains. Our data suggest that the father suffered a postzygotic mutation early in development,
but that he retained a remnant of functional SRY protein that accounts for his normal development.
Received: 18 September 1995 / Revised: 21 November 1995 相似文献
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Rafaella Fortini Queiroz Grenfell Watson Martins Martin Enk áureo Almeida Liliane Siqueira Vanessa Silva-Moraes Edward Oliveira Nídia Francisca de Figueiredo Carneiro Paulo Marcos Zech Coelho 《Memórias do Instituto Oswaldo Cruz》2013,108(3):328-334
Schistosomiasis diagnosis is based on the detection of eggs in the faeces, which is laborious and lacks sensitivity, especially for patients with a low parasite burden. Immunological assays for specific antibody detection are available, but they usually demonstrate low sensitivity and/or specificity. In this study, two simple immunological assays were evaluated for the detection of soluble Schistosoma mansoni adult worm preparation (SWAP) and egg-specific IgGs. These studies have not yet been evaluated for patients with low parasite burdens. Residents of an endemic area in Brazil donated sera and faecal samples for our study. The patients were initially diagnosed by a rigorous Kato-Katz analysis of 18 thick smears from four different stool samples. The ELISA-SWAP was successful for human diagnosis with 90% sensitivity and specificity, confirming the Kato-Katz diagnosis with nearly perfect agreement, as seen by the Kappa index (0.85). Although the ELISA-soluble S. mansoni egg antigen was 85% sensitive, it exhibited low specificity (80%; Kappa index: 0.75) and was more susceptible to cross-reactivity. We believe that immunological assays should be used in conjunction with Kato-Katz analysis as a supplementary tool for the diagnosis of schistosomiasis for patients with low infection burdens, which are usually hard to detect. 相似文献
574.
Jurgen Huybrechts Elke Clynen Arnold De Loof Liliane Schoofs 《Physiological Entomology》2003,28(1):46-53
Abstract. A simple, single-step aqueous extraction method has been developed to study the neuropeptide content of small neuroendocrine organs. Perifusion of these tissues with deionized water causes osmotic bursting of the cells and release of their content into the surrounding fluid. The neuropeptides are immediately retained from the perifusion fluid using disposable C18 cartridges. After one separation step and mass spectrometry, it was possible to identify a large number of known neuropeptides from the corpora cardiaca of Locusta migratoria (L). Also present in the extract were a number of neuropeptide fragments and two incompletely processed peptides. Using this method, a 959Da peptide present in the corpora cardiaca was sequenced de novo . The full sequence, deduced using Collision Induced Dissociation Tandem Mass Spectrometry (CID MS/MS), is Ser-Pro-Leu-Asp-Ala-His-His-Leu-Ala. This nonapeptide is predicted from the gene encoding the ion transport peptide precursor and from the gene encoding the ion transport-like peptide precursor. In both cases, this nonapeptide, which was named ion transport peptide-copeptide, is flanked by the signal sequence at the N -terminus and a dibasic cleavage site (Lys-Arg) at the C -terminus. This structural feature is common to many physiologically important locust preproneuropeptides and indicates that this copeptide might have a physiological function, but this is not yet known. 相似文献
575.
Dominique Bladier Liliane Gattegno Françoise Fabia Gérard Perret Pierre Cornillot 《Carbohydrate research》1980,83(2):371-376
The contents of fucose, mannose, galactose, glucose, 2-acetamido-2-deoxy-d-glucose and -d-galactose, and sialic acid, when the results were expressed as nmol per mg of membrane dry-weights, were found to be significantly lower in the membranes of old erythrocytes than in the membranes of young ones. No significant difference was found between young and old membranes when the compositions were expressed as residues per one hundred carbohydrate residues, suggesting that a homogeneous decrease of the carbohydrate moieties may occur during aging in vivo. 相似文献
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