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Reduced glutathione (GSH) has been demonstrated in benign and malignant human breast lesions using a newly developed histofluorescence technique. GSH was present in every lesion and in each case was localised to the epithelium. A semi-quantitative assessment revealed a moderate amount of GSH in normal epithelium and fibroadenoma and a high level in apocrine metaplasia, epitheliosis and intraduct carcinoma. Invasive ductal carcinoma contained a variable amount of GSH. Correlation between fluorescence intensity and histological grade of ductal carcinomas was almost statistically significant but a relationship to oestrogen receptor status was not detected. The rapid assessment of GSH in breast cancer may aid in the selection of optimum chemotherapeutic regimens.  相似文献   
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Background Dendritic cells (DC) mediate inflammation in rodent models of allergic airway disease, but the role played by human respiratory‐tract DC (hRTDC) in atopic asthma remains poorly defined. Recent data suggest that CD1 antigen presentation by hRTDC may contribute to asthma pathogenesis. Objective To investigate the influence of hRTDC on the balance between atopy and allergic asthma in human subjects and to determine whether CD1 expression by hRTDC is modulated during asthmatic inflammation. Methods Sputum cells were induced from steroid‐naïve, allergen‐challenged and allergen‐naïve subjects (atopic asthmatics, atopic non‐asthmatics and non‐atopic controls). hRTDC were identified using monoclonal antibody labelling and analysis by flow cytometry. Results hRTDC stained HLA‐DR+ (negative for markers of other cell lineages) were predominantly myeloid and comprised ∼0.5% of viable sputum cells. Sputum cells were potent stimulators of allogeneic CD4+ naïve T cells and enrichment/depletion experiments correlated stimulatory potency with DC numbers. Sputum contained cells that exhibited typical dendritic morphology when analysed by electron microscopy. Myeloid hRTDC were endocytically active, but uptake of FITC‐dextran was enhanced in cells from asthmatics (P<0.001). Despite their increased endocytic capacity, asthmatic myeloid hRTDC appeared mature and expressed increased levels of maturation markers (P<0.05–P<0.001), CD1c, CD1d and langerin (P<0.05). CD1c expression by asthmatic myeloid hRTDC was enhanced upon in vivo allergen challenge (three to ninefold within 24 h; P<0.05). CD11cCD123high hRTDC were only detected in asthmatic sputum and were increased in number following allergen challenge. Conclusion Despite limited cell numbers, it proved possible to analyse human RTDC in induced sputum, providing evidence that increased antigen uptake and enhanced CD1 presentation by activated hRTDC may contribute to allergic airway disease. CD1 presentation by hRTDC in atopic asthma may therefore constitute a novel target for future intervention strategies.  相似文献   
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Biochemical and molecular biological studies of osteoblastic cell function and hormonal regulation are frequently confounded by the inherent cellular heterogeneity and phenotypic instability of existing in vitro and in vivo model systems. A new technique (derived from Western blotting or antibody-based detection of protein molecules bound to nitrocellulose paper) is described for identification of individual cells which synthesize osteoblast-specific gene products (bone Gla-protein, type I collagen, and alkaline phosphatase) or produce cAMP in response to parathyroid hormone (PTH) or isoproterenol. Dispersed primary neonatal rat calvariae or osteogenic sarcoma cells were “plated” on Immobilon-P (a hydrophobic transfer membrane with very high protein-binding capacity) for 30 minutes to several hours, followed by agonist treatment, formalin fixation, hematoxylin staining, and immunostaining with a battery of antibodies specific for osteoblastic products. Individual cells and their secretory zones were visualized by light microscopy and counted. Treatment with PTH with or without isoproterenol resulted in increases in the percentages of osteoblastic cells elaborating cAMP, as well as the intensity of immunostaining, but had no effects on MCF-7 cells, a nonosteoblastic breast carcinoma control line. The percentage of cells within each primary osteoblastic cell population isolated or rat osteogenic sarcoma cell clone (G2 or C12) that elaborated bone-specific proteins or that generated cAMP in response to PTH varied with time and the individual cellular preparation, reconfirming the cellular heterogeneity of these systems. This method, in conjunction with techniques such as in vitro hybridization, should prove useful in characterizing discrete osteoblastic bone cell subpopulations and in clarifying mechanisms of hormonal regulation by local and systemic agents.  相似文献   
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Reducing the incidence and severity of post ERCP pancreatitis.   总被引:5,自引:0,他引:5  
Acute pancreatitis remains the commonest complication of ERCP (endoscopic retrograde cholangiopancreatography) with published incidence rates that have changed little over 30 years despite significant advances in endoscope and ERCP accessory technology and the introduction of structured ERCP training. Technique related risk factors for post ERCP pancreatitis have been recognised for many years and have been recently refined via large prospective audits. These studies have also revealed the importance of patient related factors and highlighted the high incidence of post ERCP pancreatitis in women being investigated for acalculus biliary pain or idiopathic recurrent acute pancreatitis. Sphincter of Oddi hypertension is often found to be present in this group of patients. Methods of preventing post ERCP pancreatitis have been sought for many years and numerous drugs have been tried using a variety of regimes with heterogeneous groups of patients. At present pancreatic duct stenting looks to be the most efficacious prophylactic method but is not for the beginner endoscopist. It is possible, however, by using a simple strategy to minimise the incidence of post ERCP pancreatitis and modulate its severity.  相似文献   
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This study evaluated the effectiveness of early orthodontic treatment with the Twin-block appliance for the developing Class II Division 1 malocclusion. This multicenter trial was carried out in the United Kingdom. A total of 174 children, aged 8 to 10 years old, with Class II Division 1 malocclusion were randomly allocated to receive treatment with a Twin-block appliance or to an untreated, control group. Data were collected at the start of the study and 15 months later. Results showed that early treatment with Twin-block appliances resulted in reduction of overjet, correction of molar relationships, and reduction in severity of malocclusion. Most of this correction was due to dentoalveolar change, but some was due to favorable skeletal change. Early treatment with the Twin-block appliance is effective in reducing overjet and severity of malocclusion. The small change in the skeletal relationship might not be considered clinically significant.  相似文献   
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