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91.
A case of a Borrmann type 2 advanced gastric cancer with endocrine differentiation is described. Histologically, the cancer was either composed of cells arranged in a tubular pattern or formed solid nests of various sizes. The tubular pattern was composed of a moderately differentiated tubular adenocarcinoma. The histology showed partial carcinoid tumor-like features. Cancer cells inside solid nests had a signet-ring cell-like appearance. Periodic-acid Schiff (PAS) staining was positive in the cytoplasm of a few of the cells found in the tubular pattern and in the mucus in some lumens and on the apical surface of cells in some lumens, but PAS did not stain cancer cells in the solid nests. Neither cancer cells nor mucus in the lumens were stained with alcian blue. All cancer cells were strongly positive for Grimelius silver stain, and most of the cancer cells stained positively for chromogranin A. Electron microscopic examination showed electron dense neuroendocrine granules in the cytoplasm of cancer cells. Cancer cells were stained positively for pancytokeratin, cytokeratin 8/18 and carcinoembryonic antigen. Muc 1 mucin glycoprotein staining was positive along the cell surfaces of cancer cells, but Muc 2, 5AC and 6 stainings were negative, although Muc 3 stained positively in the cytoplasm of a few cancer cells. The present case is a gastric tubular adenocarcinoma with Muc 1-positive, neutral- and acid mucin-negative signet-ring cell-like cells, which is associated with neuroendocrine differentiation.  相似文献   
92.
BACKGROUND: Japanese cedar pollen (JCP) sensitization and Japanese cedar pollinosis (JCPS) appear to be increasingly prevalent in younger children. The present study investigated factors affecting JCP sensitization and JCPS development in school children. METHODS: In May or June each year from 1994 to 2006, 275-510 children were assessed for serum JCP-IgE and house dust mite (HDM)-IgE levels, and surveyed regarding rhinoconjunctival symptoms. RESULTS: Strong JCP sensitization (IgE > or = 17.5 U(A)/ml) was associated with age (odds ratio (OR) = 2.65), the amount of dispersed pollen in the observed year (OR = 2.03) and in the year following birth (OR = 1.51), the month of birth (OR = 2.18), and the recent birth cohort (OR = 1.96). Symptoms were negatively correlated with the recent birth cohort (OR = 0.69) after adjusting for JCP-IgE levels. Strong HDM sensitization was associated with gender (OR = 0.65 for girls) and the recent birth cohort (OR = 1.76). CONCLUSIONS: JCP sensitization appeared to be associated with the recent birth cohort and to increases in dispersed pollen just after birth and in the observed season. Although the recent birth cohort was more easily sensitized, they were not more likely to develop symptoms. In contrast to JCP sensitization, strong HDM sensitization appeared to develop prior to commencement of primary school and was more likely to affect boys.  相似文献   
93.
Predictors for typical asthma onset from cough variant asthma.   总被引:6,自引:0,他引:6  
Cough variant asthma is recognized to be a precursor of asthma or preasthmatic state because nearly 30% patients with cough variant asthma develop typical asthma within several years. However, predictors for risk of typical asthma onset from cough variant asthma are unknown. Forty-one patients with cough variant asthma (median age 50 years, 13 men and 28 women), who had undertaken spirometry, bronchial reversibility test, methacholine provocation test, measurements of peripheral blood eosinophil count, serum total IgE, and specific IgE to common allergens, and induced sputum eosinophil count at presentation, were followed up with special emphasis on typical asthma onset during 1 year or more (median 4 years, range 1-12.4). Long-term inhaled corticosteroids (ICS) were taken in 27 patients. Univariate and multivariate logistic analyses were performed to determine the predictors for typical asthma onset. Asthma onset was recognized in 7 patients. Bronchial hyperresponsiveness, peripheral blood eosinophil count, and no use of ICS were significant predictors for the typical asthma onset by univariate analysis. However, only bronchial hyperresponsiveness was the significant predictor when multivariate analysis was used (adjusted OR 0.028, 95% CI 0.001-0.783, p = 0.0355). Bronchial hyperresponsiveness may be the most important predictor for risk of typical asthma onset from cough variant asthma.  相似文献   
94.
Epithelial-mesenchymal transformation is a critical developmental process reiterated in multiple organs throughout embryogenesis. Formation of endocardial cushions, primordia of valves and septa, is a classic example of epithelial-mesenchymal transformation. Several gene mutations are known to affect cardiac valve formation. Sox9 is activated when endocardial endothelial cells undergo mesenchymal transformation and migrate into an extracellular matrix, called cardiac jelly, to form endocardial cushions. In Sox9-null mutants, endocardial cushions are markedly hypoplastic. In these mutants, Nfatc1 is ectopically expressed and no longer restricted to endothelial cells. Further, Sox9-deficient endocardial mesenchymal cells fail to express ErbB3, which is required for endocardial cushion cell differentiation and proliferation. Our results reveal a succession of molecular steps in the pathway of endocardial cushion development. We propose that loss of Sox9 inhibits epithelial-mesenchymal transformation after delamination and initial migration, but before definitive mesenchymal transformation.  相似文献   
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