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Morphological study of the prostate gland in viscacha (Lagostomus maximus maximus) during periods of maximal and minimal reproductive activity 下载免费PDF全文
Maximiliano Chaves Claudia Aguilera‐Merlo Albana Cruceño Teresa Fogal Fabian Mohamed 《Anatomical record (Hoboken, N.J. : 2007)》2015,298(11):1919-1931
The viscacha (Lagostomus maximus maximus) is a rodent with photoperiod‐dependent seasonal reproduction. The aim of this work was to study the morphological variations of the prostate during periods of maximal (summer, long photoperiod) and minimal (winter, short photoperiod) reproductive activity. Prostates of adult male viscachas were studied by light and electron microscopy, immunohistochemistry for androgen receptor, and morphometric analysis. The prostate consisted of two regions: peripheral and central. The peripheral zone exhibited large adenomeres with a small number of folds and lined with a pseudostratified epithelium. The central zone had small adenomeres with pseudostratified epithelium and the mucosa showed numerous folds. The morphology of both zones showed variations during periods of maximal and minimal reproductive activity. The prostate weight, prostate‐somatic index, luminal diameter of adenomeres, epithelial height and major nuclear diameter decreased during the period of minimal reproductive activity. Principal cells showed variations in their shape, size and ultrastructural characteristics during the period of minimal reproductive activity in comparison with the active period. The androgen receptor expression in epithelial and fibromuscular stromal cells was different between the studied periods. Our results suggest a reduced secretory activity of viscacha prostate during the period of minimal reproductive activity. Thus, the morphological variations observed in both the central and peripheral zones of the viscacha prostate agree with the results previously obtained in the gonads of this rodent of photoperiod‐dependent reproduction. Additionally, the variations observed in the androgen receptors suggest a direct effect of the circulating testosterone on the gland. Anat Rec, 298:1919–1931, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Teaching Point: Subcutaneous nodules sparing the dermis and without extracutaneous involvement is a rare presentation of the diffuse large B-cell lymphoma. 相似文献
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Chaves Paula Resende Daher Mendonça Thays Santos de Oliveira Baldoni André Sanches Cristina dos Santos Thais Bueno Enes Pereira Mariana Linhares 《International journal of clinical pharmacy》2019,41(3):677-681
International Journal of Clinical Pharmacy - Background The effectiveness of pharmaceutical care has already been evidenced in several studies and scenarios; the lack of patient’s... 相似文献
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Mutations in the rpoB gene of rifampin-resistant Mycobacterium tuberculosis isolates in Spain and their rapid detection by PCR-enzyme-linked immunosorbent assay 总被引:1,自引:0,他引:1 下载免费PDF全文
Garcia L Alonso-Sanz M Rebollo MJ Tercero JC Chaves F 《Journal of clinical microbiology》2001,39(5):1813-1818
Genetic alterations in the rpoB gene were characterized in 50 rifampin-resistant (Rif(r)) clinical isolates of Mycobacterium tuberculosis complex from Spain. A rapid PCR-enzyme-linked immunosorbent assay (ELISA) technique for the identification of rpoB mutations was evaluated with isolates of the M. tuberculosis complex and clinical specimens from tuberculosis patients that were positive for acid-fast bacilli (AFB). Sequence analysis demonstrated 11 different rpoB mutations among the Rif(r) isolates in the study. The most frequent mutations were those associated with codon 531 (24 of 50; 48%) and codon 526 (11 of 50; 22%). Although the PCR-ELISA does not permit characterization of the specific Rif(r) allele within each strain, 10 of the 11 Rif(r) genotypes were correctly identified by this method. We used the PCR-ELISA to predict the rifampin susceptibility of M. tuberculosis complex organisms from 30 AFB-positive sputum specimens. For 28 samples, of which 9 contained Rif(r) organisms and 19 contained susceptible strains, results were concordant with those based on culture-based drug susceptibility testing and sequencing. Results from the remaining two samples could not be interpreted because of low bacillary load (microscopy score of 1+ for 1 to 9 microorganisms/100 fields). Our results suggest that the PCR-ELISA is an easy technique to implement and could be used as a rapid procedure for detecting rifampin resistance to complement conventional culture-based methods. 相似文献
48.
Sara Pereira Peter T. Katzmarzyk Thayse Natacha Gomes Michele Souza Raquel N. Chaves Fernanda K. dos Santos 《Annals of human biology》2017,44(4):316-324
Background: Somatotype is a complex trait influenced by different genetic and environmental factors as well as by other covariates whose effects are still unclear.Aims: To (1) estimate siblings’ resemblance in their general somatotype; (2) identify sib-pair (brother–brother (BB), sister–sister (SS), brother–sister (BS)) similarities in individual somatotype components; (3) examine the degree to which between and within variances differ among sib-ships; and (4) investigate the effects of physical activity (PA) and family socioeconomic status (SES) on these relationships.Subjects and methods: The sample comprises 1058 Portuguese siblings (538 females) aged 9–20 years. Somatotype was calculated using the Health-Carter method, while PA and SES information was obtained by questionnaire. Multi-level modelling was done in SuperMix software.Results: Older subjects showed the lowest values for endomorphy and mesomorphy, but the highest values for ectomorphy; and more physically active subjects showed the highest values for mesomorphy. In general, the familiality of somatotype was moderate (ρ?=?0.35). Same-sex siblings had the strongest resemblance (endomorphy: ρSS > ρBB > ρBS; mesomorphy: ρBB = ρSS > ρBS; ectomorphy: ρBB > ρSS > ρBS). For the ectomorphy and mesomorphy components, BS pairs showed the highest between sib-ship variance, but the lowest within sib-ship variance; while for endomorphy BS showed the lowest between and within sib-ship variances.Conclusions: These results highlight the significant familial effects on somatotype and the complexity of the role of familial resemblance in explaining variance in somatotypes. 相似文献
49.
P. Padilla J.M. Górriz J. Ramírez E.W. Lang R. Chaves F. Segovia M. López D. Salas-González I. Álvarez 《Neuroscience letters》2010
This letter presents a novel computer-aided diagnosis (CAD) technique for the early diagnosis of Alzheimer's disease (AD) based on non-negative matrix factorization (NMF) analysis applied to single photon emission computed tomography (SPECT) images. A baseline normalized SPECT database containing normalized data for both AD patients and healthy reference patients is selected for this study. The SPECT database is analyzed by applying the Fisher discriminant ratio (FDR) for feature selection and NMF for feature extraction of relevant components of each subject. The main goal of these preprocessing steps is to reduce the large dimensionality of the input data and to relieve the so called “curse of dimensionality” problem. The resulting NMF-transformed set of data, which contains a reduced number of features, is classified by means of a support vector machines based classification technique (SVM). The proposed NMF + SVM method yields up to 94% classification accuracy, with high sensitivity and specificity values (upper than 90%), becoming an accurate method for SPECT image classification. For the sake of completeness, comparison between another recently developed principal component analysis (PCA) plus SVM method and the proposed method is also provided, yielding results for the NMF + SVM approach that outperform the behavior of the reference PCA + SVM or conventional voxel-as-feature (VAF) plus SVM methods. 相似文献
50.
Raquel Nichele de Chaves Adam Baxter-Jones Daniel Santos Thayse Natacha Gomes Fernanda Karina dos Santos Michele Caroline de Souza 《Annals of human biology》2014,41(2):159-167
Aim: The purposes of this study were: (i) to identify familial resemblances in body fat, blood pressure (BP) and total physical activity (TPA); (ii) to estimate the magnitude of their genetic and environmental influences; and (iii) to investigate shared familial aggregation among these phenotypes.Subjects and methods: The sample comprised 260 nuclear families from Portugal. Body fat was assessed by bioelectrical impedance. BP was measured by an oscillometric device. TPA was estimated by the Baecke questionnaire. Familial correlation analyses were performed using Generalized Estimating Equations. Quantitative genetic modelling was used to estimate maximal heritability, genetic and environmental correlations.Results: Familial intra-trait correlations ranged from 0.15–0.38. Genetic and common environmental factors explained from 30%--44% of fat mass depots and BP and 24% of TPA. Genetic correlations were significant between BP and the fat mass traits (p?0.05). Environmental correlations were statistically significant between diastolic BP and total body fat, trunk fat and arm fat (p?0.05) and TPA and other phenotypes.Conclusions: The results suggest familial resemblance in the variation of body fat, BP and TPA, showing partial pleiotropic effects in the variation in body fat phenotypes and BP. TPA only shares common environmental influences with BP and body fat traits. 相似文献