<正> “人生七十古来稀”的说法早已成为过去。《美国新闻与世界报导》在1995年6月12日的一篇文章中说,“An American woman who today reach-es age 50 free of cancer and heart disease can expect to see her 92nd birthday.The average man who is 65 today-an age now reached by more than 70percent of the U.S.population-can expect 10 live until 81”。人的生命周期(life cycle)已经发生了根本性的变化,用这位作者的话