医学上称45至60岁这一年龄段的人为中年人。中年人犹如正午的大阳，是人生中最辉煌。最鼎盛的时期。然而，就是在事业、家庭、生活的风帆驶向成功彼岸之际，中年人的生理和心理却开始发生了不可忽视的变化，正如月盈月亏一样。尽管这一过程是缓慢的、无形的，在较长一段时间内 Medically 45 to 60 years old this age group of middle-aged people. Middle-aged like noon sun, is the most brilliant in life. The most prosperous period. However, just as the sails of the cause, family and life sail to the other side of the river, the physiology and psychology of middle-aged people begin to change in a negligible amount. Although this process is slow and invisible, over a longer period of time