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891.
Magdy S. Aly Paola Dal Cin Herman Van Den Berghe Wim Van De Voorde Hein Van Poppel Filip Ameye Luc Baert 《Genes, chromosomes & cancer》1994,9(4):227-233
We combined conventional cytogenetic analysis and fluorescence in situ hybridization of short-term cultures of 28 samples from benign prostatic hyperplasia. Lou of the Y chromosome was the most common chromosome change, followed by trisomy 7. Trisomy 7, however, may be unrelated to the origin of benign prostate hyperplasia, in which the only and not very specific change seems to be the loss of the Y chromosome. Genes Chrom Cancer 9:227-233 (1594). © 1994 Wiley-Liss, Inc. 相似文献
892.
Noninvasive measurement of human forearm oxygen consumption by near infrared spectroscopy 总被引:5,自引:0,他引:5
Roberto A. De Blasi Mark Cope Clare Elwell Fauzia Safoue Marco Ferrari 《European journal of applied physiology》1993,67(1):20-25
Summary This study reported on the application of near infrared spectroscopy (NIRS) to noninvasive measurements of forearm brachio-radial muscle oxygen consumption (
O2) and recovery time (t
r) in untrained volunteers. Seven healthy subjects were submitted to four consecutive protocols involving measurements made at rest, the induction of an ischaemia, and during a maximal increase of metabolic demand achieved with and without vascular occlusion. Two isometric maximal voluntary contractions (MVC) of 30-s duration were executed with and without vascular occlusion and a 50% MVC lasting 125 s was also performed. The protocols were repeated on 2 different days. The results showed that, during vascular occlusion at rest, the time to 95% of the final haemoglobin (Hb) + myoglobin (Mb) desaturation value was independent of
O2. The MVC, performed during vascular occlusion, caused complete Hb + Mb desaturation in 15–20 s, which was not followed by any further desaturation when the second contraction was performed. No difference was found between
O2during MVC with and without vascular occlusion. A consistent difference was seen between
O2measured during occlusion at rest and
O2measured during MVC with and without occlusion. During prolonged exercise (125 s) Hb + Mb desaturation was maintained for the whole contraction period. The results of this study show that
O2can be measured noninvasively by NIRS. The
O2during MVC was very similar both in the presence and absence of blood flow limitation in most of the subjects tested. This would suggest that muscle
O2might be accurately evaluated dynamically without cuff occlusion. 相似文献
893.
Cytokeratin (CK) expression was investigated, by means of immunocytochemistry, in
the hamster thymic epithelium during ontogeny, as well as in primary cultures and
upon glucocorticoid hormone treatment in vivo. As compared to the distribution pattern
of distinct monoclonal antibody-defined cytokeratins in the normal adult thymus, CK
modulation was evidenced in the three situations studied. During thymus ontogeny,
both cytokeratins of simple lining epithelia, as CK8 and CK18, as well as the CK1/CK10
pair (typical marker of terminal stage of keratinization), were expressed since early
stages of thymus development. They were located in the central region of thymic lobules
preceding the cortical-medullary distinctions. This differed from what had been
previously shown for mouse thymus ontogeny, revealing that the interspecific diversity
in the distribution pattern of thymic cytokeratins occurred early in fetal life. A
modulation of CK expression was also detected when hamster thymic epithelial cells
(TEC) were led to grow in culture, with a down-regulation of CK19 contrasting with an
enhancement of CK18 expression. This diverged from the maintenance of the in situ
pattern when human TEC were cultured. Last, in vivo hydrocortisone treatment, known
to increase the numbers of KL1+ cells in the mouse thymus medulla, promoted a cortical
expression of the CK1/CK10 pair in the hamster thymus. Taken together, our findings
demonstrate a continuous plasticity of the thymic epithelium, at least regarding
cytokeratin expression, and enlarge the concept of interspecific diversity of intrathymic
CK distribution in conditions as morphogenesis, in vitro system, and responsiveness to
glucocorticoid hormone treatment. 相似文献
894.
Paola Dal Cin Chris De Wolf-Peeters Magdy S. Aly Georges Deneffe Walter Van Mieghem Herman Van Den Berghe 《Genes, chromosomes & cancer》1993,6(4):243-244
Cytogenetic analysis of a thymoma showed the presence of a ring chromosome 6 as the sole chromosome abnormality. © 1993 Wiley-Liss, Inc. 相似文献
895.
G T Thomson B Chiu D De Rubeis J Falk R D Inman 《Clinical immunology and immunopathology》1992,64(3):227-232
Following a foodborne outbreak of Salmonella dysentery in a group of 79 women and 4 men, 6 individuals were found to have reactive arthritis (ReA). None of the affected individuals had the classical genetic marker HLA B27 although 2 of the 6 had CREG antigens. IgA antibodies to the lipopolysaccharide of the causative organism, Salmonella heidelberg, were found to be elevated in those patients with active ReA compared to those with inactive ReA or those who had dysentery but did not develop ReA. The lymphocyte proliferative response to both PHA and the whole S. heidelberg organism was impaired in the patients with ReA (active or inactive) compared with the non-ReA patient controls. In this predominantly female outbreak of Salmonellosis, the development of ReA lacked an association with HLA class I antigens commonly recognized. 相似文献
896.
Lipid abnormalities in HIV-infected patients are not correlated with lopinavir plasma concentrations
897.
Filho OG Gordan AN Mello Rde A Neto CS Heinke T 《International journal of surgical pathology》2004,12(2):151-153
Hamartomas were first described by Albrecht in 1904, who defined them as tumor-like malformations in which there was abnormal blending of the normal components of an organ. The myoid hamartoma is a rare benign lesion of the breast and has an uncertain origin, possibly in the walls of the blood vessels, muscularis mammillae of the areolae, and mainly in myoepithelium. We report 3 cases of myoid hamartomas of the breast, with the clinical, radiologic, and histopathological findings, and review the literature. The 3 lesions showed normal breast ducts and lobules, entrapped by a muscular stroma and some foci of mature adipose tissue. The muscular origin of part of the stroma was confirmed by strong reactiveness with smooth-muscle actin. 相似文献
898.
Emergence of extended-spectrum-beta-lactamase (CTX-M-9)-producing multiresistant strains of Salmonella enterica serotype Virchow in poultry and humans in France 总被引:1,自引:0,他引:1 下载免费PDF全文
Weill FX Lailler R Praud K Kérouanton A Fabre L Brisabois A Grimont PA Cloeckaert A 《Journal of clinical microbiology》2004,42(12):5767-5773
During 2002 to 2003, eight Salmonella enterica serotype Virchow poultry and poultry product isolates from various sources (chicken farms, poultry slaughterhouse, or retail store) and one S. enterica rough strain isolated from human feces were found to produce extended-spectrum beta-lactamase CTX-M-9. Poultry and poultry product isolates were recovered from different locations in the southwest of France. The human rough isolate had sequences of flagellin genes (fliC and fljB) typical of serotype Virchow and ribotyping and pulsed-field gel electrophoresis (PFGE) patterns closely similar to those of serotype Virchow strains. PFGE confirmed the clonal relationship between the poultry isolates, while the human isolate displayed a pattern with 94% homology. The bla(CTX-M-9) gene was located on a conjugative plasmid and was shown to be linked to orf513. Plasmid profiling found a very similar EcoRI restriction pattern in six transconjugants studied, including transconjugants obtained from the human isolate. A single hatchery, supplying chicks to the six farms, was identified. Emergence of extended-spectrum beta-lactamase-producing S. enterica strains in food animals is a major concern, as such strains could disseminate on a large scale and lead to antibiotic therapy difficulties. 相似文献
899.
900.
Sensitive and viable identification of antigen-specific CD8+ T cells by a flow cytometric assay for degranulation 总被引:15,自引:0,他引:15
Betts MR Brenchley JM Price DA De Rosa SC Douek DC Roederer M Koup RA 《Journal of immunological methods》2003,281(1-2):65-78
Flow cytometric detection of antigen-specific CD8+ T cells has previously been limited to MHC-class I tetramer staining or intracellular cytokine production, neither of which measure the cytolytic potential of these cells. Here we present a novel technique to enumerate antigen-specific CD8+ T cells using a marker expressed on the cell surface following activation induced degranulation, a necessary precursor of cytolysis. This assay measures the exposure of CD107a and b, present in the membrane of cytotoxic granules, onto the cell surface as a result of degranulation. Acquisition of cell surface CD107a and b is associated with loss of intracellular perforin and is inhibited by colchicine, indicating that exposure of CD107a and b to the cell surface is dependent on degranulation. CD107a and b are expressed on the cell surface of CD8+ T cells following activation with cognate peptide, concordant with production of intracellular IFNgamma. Finally, CD107-expressing CD8+ T cells are shown to mediate cytolytic activity in an antigen-specific manner. Measurement of CD107a and b expression can also be combined with MHC-class I tetramer labeling and intracellular cytokine staining to provide a more complete assessment of the functionality of CD8+T cells expressing cognate T cell receptors (TCR). 相似文献