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81.
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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This paper discusses the consequences in rural India of a certain rational household decision function on the number of children born in the family when birth control opportunities are available. Households are assumed to choose whether or not to practice birth control after each child is born on the basis of maximising expected utility as a function of the consumption per head and the number of members in the family. Uncertainty arises on account of the different evaluation of children of different sexes. The model is then used to predict how completed family size would change if a government agency paid bonuses for smaller families. 相似文献
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This study examines revenue sharing in sports leagues where franchises engage in multiple types of investments. Previous literature typically treats revenues and investments as homogeneous, but we add to the literature by differentiating between investment types and revenue sources. This is important because investment in talent leads to winning, which is a zero-sum game for the league and therefore owners have an incentive to limit talent investment. However, other investments, such as stadiums, are not a zero-sum game, and therefore the implications of revenue sharing are different for the league. We provide sufficient conditions under which it is more efficient to share media revenue compared to stadium revenue. We conclude by providing applications of this model. 相似文献
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This paper examines whether the cross sectional variation in Australian share prices is partially explained by measures of firm size and ownership characteristics in a manner that is consistent with firms behaving in accordance with Merton's (1987) model of capital market equilibrium with incomplete information. Based on a sample of firms whose shares were traded on the ASX during 1995, we show that firms largely owned by less wealthy shareholders tend to have low stock prices, although this relation is not linear. In addition, larger, better–known, firms tend to have higher stock prices. These findings are consistent with prior evidence from US markets, and suggest the existence of a shareholder clientele effect in Australia that is related to the share price of the underlying firm. 相似文献