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Socially amoral economic forces now drive health system change. The authors, assisted by a panel of experts on employers, health plans, providers, and consumers, discuss current drivers such as (1) employers' price-focused purchasing, without good quality/value measures; (2) health plans' growing successes and market clout; (3) providers declining prospects and fears about their future; and (4) consumers' worries about less choice. Future influences will include Medicare reforms, better information, and pro-consumer regulation of managed care, as well as rising social distress. The health system's future is now open for resolution in an evolving, imperfect market.  相似文献   
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The effect of a polyclonal antiserum and OMVU10, a monoclonal antibody reactive with Antigen B of Streptococcus sobrinus, on the interaction of polymorphonuclear leukocytes with S. sobrinus was studied, using chemiluminescence and bacterial killing assays. Increased stimulation of neutrophils as measured in the chemiluminescence assays was established when S. sobrinus was preincubated with polyclonal antiserum or when polyclonal antiserum was added to the reaction mixture. Higher counts were measured in comparison to preimmune serum. After 90 min, 52% of S. sobrinus preincubated with polyclonal antiserum was killed. Killing was also increased when polyclonal antiserum was added to the reaction mixture in comparison to the controls. No killing was found when bacteria were preincubated with OMVU10 or when OMVU10 was added to the reaction mixture in comparison to Clone 24, a control antibody.  相似文献   
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Models of the relations between contact with pets and better health are examined in an archival prospective study using data derived from the longitudinal study initiated by Terman in 1921 (current N?=?343 men, 300 women) . In survival analyses of documented longevity, playing with pets in 1977 (M age?=?67 years) was not associated with mortality risk through 1991 for the total sample nor for those who were unmarried or those who were less satisfied with their human relationships. Playing with pets was not associated with health-prone attributes or healthy behaviors such as personality, social ties, education, and smoking. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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Appendage formation in insects and vertebrates depends upon signals from both the anterior-posterior and dorsal-ventral (DV) axes. In Drosophila, wing formation is organized symmetrically around the DV boundary of the growing wing imaginal disc and requires interactions between dorsal and ventral cells. Compartmentalization of the wing disc, dorsal cell behavior, and the expression of two dorsally expressed putative signaling molecules, fringe (fng) and Serrate (Ser), are regulated by the apterous selector gene. Here, we demonstrate that fng and Ser have distinct roles in a novel cell recognition and signal induction process. fng serves as a boundary-determining molecule such that Ser is induced wherever cells expressing fng and cells not expressing fng are juxtaposed. Ser in turn triggers the expression of genes involved in wing growth and patterning on both sides of the DV boundary.  相似文献   
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