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Ewy GA 《Journal of insurance medicine (New York, N.Y.)》2004,36(4):292-297
Diastolic dysfunction of the heart is characterized by normal left ventricular contractility and normal ejection fraction, however ventricular relaxation is impaired. In systolic dysfunction, ventricular contractility and ejection fraction are reduced, in addition to impaired relaxation. The prevalence of diastolic dysfunction is increased in the elderly, especially those who have had inadequately treated hypertension. Both diastolic and systolic dysfunction may result in similar clinical signs and symptoms. Therefore, echocardiography is needed to make the distinction. Left atrial (LA) enlargement, assessed by left atrial volume indexed to body surface area, appears to be the best measure to assess diastolic function. LA enlargement is likely when indexed LA volume is > or = 34-40 mL/m2. B-type natriuretic protein appears to be useful for the diagnosis, assessment and prognosis of heart failure, but it does not distinguish between the two types of dysfunctions. Several drug treatments that have effects on the mechanism of diastolic dysfunction are under investigation. 相似文献
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Vonderheid S Pohl J Schafer P Forrest K Poole M Barkauskas V Mackey TA 《Nursing economic$》2004,22(3):124-34, 107
Financial performance measures are essential to improve the fiscal management of academic nurse-managed centers (ANMCs). Measures are compared among six ANMCs in a consortium and against an external, self-sustainable, profitable ANMC and national data for family practice physicians. Performance measures help identify a center's strengths and weaknesses facilitating the development of strategies aimed at a variety of targets (business practices related to revenue and costs) to improve financial viability. Using a variety of financial performance measures to inform decision making will aid ANMCs in keeping their doors open for business. 相似文献
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A. N. Rae 《Journal of Agricultural Economics》1970,21(1):133-140
This paper discusses the determination of profit-maximising behaviour under conditions of imperfect competition in product and/or factor markets. After stating a quadratic programming model which restricts product demand and factor supply functions to a linear form, an empirical application to a New Zealand nursery firm is discussed. It is concluded that such quadratic programming models should have an important role to play in horticultural management 相似文献
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International assistance agencies have turned increasingly to integrated rural development policies in an attempt to ameliorate the inequitable distribution of economic growth plaguing Third World nations since World War II. This paper reviews the functionally and spatially integrated investment strategies of the World Bank, USAID and the United Nations, outlines their objectives, perceptions of the problem, basic assumptions and programmes, and evaluates them in terms of potential difficulties for implementation. Those factors crucial to making integrated development policies operational — knowledge of human ecosystems in rural areas, analytical ability, operational procedures, arrangements for local participation, subsistence systems indicators and administrative capacity of local and national governments — are discussed and assessed. 相似文献