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Tissue sections of 81 breast carcinomas and 19 benign breast tissues were immunostained with a monoclonal antibody to the bcl-2 gene product, a cytoplasmic protein that regulates apoptosis. The degree of immunoreactivity was then compared with clinicopathologic parameters and to immunostaining for mutated p53 gene product. Immunoreactivity for bcl-2 was present consistently in lymphocyte populations and in residual benign lobules. Apocrine metaplasia (n = 6) and lactating breast (n = 1) exhibited minimal bcl-2 expression, whereas duct hyperplasia (n = 10) showed staining of cells primarily at the periphery of the involved structure and adenosis (n = 7) displayed staining in a majority of cells. Neoplastic epithelial bcl-2 immunoreactivity was negative or minimally positive (staining in 1-5% of cells) in 42% of cases, heterogeneous (staining in 6-30% of cells) in 27% of cases, and diffuse (> 30% of cells) in 31% of cases. Immunostaining for bcl-2 correlated with the presence of estrogen receptor (bcl-2 negative, 16% estrogen receptor positive versus bcl-2 positive, 88% estrogen receptor-positive; P < 0.001), with differentiation (bcl-2 negative, 62% poorly differentiated versus bcl-2 positive, 8% poorly differentiated; P < 0.001) and with better disease-free survival (bcl-2 negative, 82% recurrence versus bcl-2 positive, 28% recurrence; P = 0.0001; 52-mo mean follow-up). Immunostaining for p53 in greater than 5% of tumor cells was observed in 39% of cases and was more frequent in bcl-2-negative tumors (18/35, 51%) as opposed to bcl-2-positive tumors (14/46, 30%); P = NS. Disease recurrence correlated with p53 staining, which was observed in 51% of tumors that relapsed versus only 22% of tumors that did not recur. We conclude that bcl-2 is expressed in benign breast tissues that retain proliferative capacity and partial differentiation. Moreover, in neoplastic breast tissue, it is better correlated with a differentiated, "hormonally responsive," prognostically favorable phenotype than with disabled p53 gene function.  相似文献   
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In this article we describe novel, water-based, crosslinkable fluorinated polymers that form coatings with excellent antigraffiti properties. The synthesis of the binders and the surface and bulk properties of their coatings are discussed. The surface properties of these coatings are characterized in terms of their surface-free energy, as calculated from static contact angle measurements. The distribution of the fluorine atoms throughout the coating is measured by X-ray photoelectron spectroscopy (XPS). The bulk properties are studied by determining the crosslink density through dynamic mechanical thermal analysis (DMTA), and the effect of the crosslinking conditions on the crosslink density and the antigraffiti properties is discussed. The results indicate that a combined action of surface and bulk properties gives these coatings their excellent antigraffiti properties. The applicability of these polymers as protective coatings for metal and concrete surfaces are demonstrated. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL  相似文献   
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A majority of performing arts organizations active in classical music, theatre, and contemporary dance rely on funding from “third parties” in order to organize productions in a recurrent manner. We adopt an entrepreneurial perspective to inform the debate on the economic sustainability of performing arts organizations: Is it a “deficit” in entrepreneurial orientation that condemns these organizations to financial dependence? Relying on a comparative case study design (n = 12), we distill a process model of performing arts entrepreneurship (PAE), which we compare with insights on innovative entrepreneurship. Our findings reveal that it is neither a lack of entrepreneurial dynamics nor the presence of opposing logics that creates dependence on multiple revenue streams. The introduction of a second revenue stream follows from adhering to artistic distinctiveness. Implications for practice and theory are elaborated.  相似文献   
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This paper explores through case studies the quality of water service delivery in four different water utilities in Kenya and Ghana. The research confirms that the utilities’ current performance indicators by themselves are insufficient to assess the access of users to good-quality water service delivery. The case studies show that low-income populations receive a poor quality of water service delivery. The paper concludes that benchmarking needs to be complemented with a more in-depth analysis of the water service delivery by water providers.  相似文献   
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Objectives: To compare health-related quality of life and depression between individuals with an inability to smell (anosmia) and a comparison group of individuals with a normal sense of smell. Methods: Ninety individuals from an anosmia organization (anosmia based on self-report) were compared to 89 individuals with a normal sense of smell. The SF-36 and Beck Depression Inventory-II-NL (BDI-II-NL) were administered, along with the Questionnaire for Olfactory Dysfunction (QOD) to assess the degree of problems in daily life related to the smell impairment. Results: Compared to the comparison group, scores in the anosmia group differed on: the QOD-subscale Life Quality (related to tasting and smelling: p p Social Functioning, Vitality, Mental Health and General Health (p’s p  相似文献   
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