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1.
The value that willed body donors provide to medical education is priceless. Their precious gift helps to teach anatomy, spatial relationships between morphological structures, anatomical variation, and professionalism to medical students in a way that plastic models, podcasts, and lectures cannot. They are also an important resource for medical research and a wide variety of postgraduate training opportunities. While many body donation programs throughout the world are nonprofit organizations, there are body donation companies in the United States that sell donors for-profit. These “body brokers” have accumulated large profits from this business. It is incongruous that others would profit from such a priceless, freely donated gift. To prevent this incongruity, it is proposed that the international anatomical community develop a normative culture (a bioethos) for body donation programs. This would involve the conscious and systematic development of ethical principles for the day-to-day policies and practices of institutions that collect and use human bodies. With the development of this bioethos, a cultural shift in how donors are treated would occur and, over time, this would become the normal practice. These principles would become fundamental and foundational for the procurement and use of priceless human tissues.  相似文献   
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We analyse the evolution of the slope (critical speed) and the y-intercept (anaerobic distance capacity) of the linear distance-time relationship over a century of Olympic running performances. The distance-time relationship of each Olympic Games (1920-2004) was plotted using the performances in the 800-, 1500- and 5000-m track events. Values for critical speed and anaerobic distance capacity were determined by linear modelling. Mean performances for the 800, 1500 and 5000 m were 104.9 +/- 1.5 s (1.4%), 217.2 +/- 2.8 s (1.3%) and 808.9 +/- 18.4 s (2.3%), respectively. Critical speed improved during the first three-quarters of the twentieth century to reach a plateau in 1984. This is in accordance with the literature (Peronnet & Thibault, 1989) and suggests that "human aerobic endurance" has improved within the century (+13.4%) and tends to stabilize. Anaerobic distance capacity was highly variable over the century (coefficient of variation = 9.4%) and did not show a linear improvement over the years as has previously been suggested (Peronnet & Thibault, 1989). This could be due to an artefact in the application of the two-parameter model to only three Olympic performances. A limitation to the use of this linear mathematical model to fit physiological data may have been demonstrated.  相似文献   
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