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511.
ND Wong RC Detrano G Diamond C Rezayat R Mahmoudi EC Chong W Tang G Puentes X Kang D Abrahamson 《Canadian Metallurgical Quarterly》1996,78(11):1220-1223
We evaluated the extent to which cardiovascular risk-reducing behaviors are initiated as a result of knowledge of newly detected coronary artery disease, based on test results from noninvasive electron beam computed tomography (EBCT). A total of 703 men and women, aged 28 to 84 years, asymptomatic and without prior coronary disease, who had a baseline EBCT coronary artery scan and basic medical history and risk factor information completed a follow-up survey questioning them about health behaviors undertaken since their scan. Baseline calcium scores were significantly higher in those who subsequently reported consulting with a physician, or reported new hospitalization, coronary revascularization, beginning aspirin usage, blood pressure medications, cholesterol-lowering therapy, decreasing dietary fat, losing weight, beginning vitamin E, and under more worry (all p <0.01). Other factors, including reducing time worked, obtaining life insurance, losing employment, increased work absenteeism, increasing exercise, or stopping smoking were not associated with coronary calcium. In logistic regression, after adjusting for age, gender, pre-existing high cholesterol, high blood pressure, cigarette smoking, and a positive family history of coronary disease, the natural log of total calcium score remained associated with new aspirin usage, new cholesterol medication, consulting with a physician, losing weight, decreasing dietary fat, new coronary revascularization (all p <0.01), but also new hospitalization (p <0.05) and increased worry (p <0.001). The results suggest that potentially important risk-reducing behaviors may be reinforced by the knowledge of a positive coronary artery scan, independent of preexisting coronary risk factor status. 相似文献
512.
MD Simms M Freundlich ES Battistelli ND Kaufman 《Canadian Metallurgical Quarterly》1999,78(1):166-183
As the 20th century draws to a close, fundamental changes in the organization, financing, and delivery of health care and welfare services, principally directed at poor families, are likely to result in an increased number of children entering out-of-home care. These children typically have significant physical, mental health, and developmental problems. Whether the quality of health care services they receive will improve as a result of health care reform efforts and new approaches to service delivery remains to be seen. This article addresses some of the major changes wrought by welfare and health care reform and describes the essential features of a health care system that can meet the special needs of children in care. 相似文献
513.
We have found that modification of rat PC12 cells with pertussis toxin resulted in an approximately 50% inhibition of a protein phosphatase 2A-like phosphatase. Protein phosphatase 2A (PP2A) is a major cellular serine/threonine-specific protein phosphatase. Treatment of extracts from pertussis toxin-modified PC12 cells with either immobilized alkaline phosphatase or Ca2+ reversed this inhibition. Reactivation of the PP2A-like phosphatase in Ca2+ appears to result from the dephosphorylation of a protein by the Ca2+/calmodulin-dependent protein phosphatase calcineurin. The PP2A-like phosphatase in extracts from pertussis toxin-modified PC12 cells eluted from a Mono Q column at a higher ionic strength than did the PP2A-like phosphatase in extracts from control cells. After incubation in Ca2+, the PP2A-like phosphatase in extracts from pertussis toxin-modified cells eluted from a Mono Q column at the same ionic strength as did the PP2A-like phosphatase in extracts from control cells. These results indicate that the effect of pertussis toxin on this PP2A-like activity results from the phosphorylation of either one of the subunits of the PP2A-like phosphatase or a protein that when phosphorylated binds to and inhibits this phosphatase. Pertussis toxin modification did not result in the phosphorylation of the catalytic subunit of PP2A. Because phosphorylation regulates the activities of many enzymes and cell surface receptors, a pertussis toxin-induced decrease in PP2A activity could alter signaling pathways and other cellular processes in which G proteins are not directly involved. 相似文献