生物节律是生命现象的基本特征之一。依照节律的周期长短可将之分为三种类型:( 1)近日节律(circadianrhythm ,或称昼夜节律,diurnalrhythm) ,节律周期接近2 4h ;( 2 )超日节律(ultradianrhythm) ,节律周期明显短于2 4h ,一般短于2 0h ,可为数小时、数分、甚至数秒;( 3)亚日节律 Biological rhythm is one of the basic characteristics of the phenomenon of life. According to the rhythm of the length of the cycle can be divided into three types: (1) recent circadian rhythm (circadianrhythm, or circadian rhythm, diurnal rhythm), the rhythm cycle close to 24h; (2) ultradianrhythm (ultradianrhythm), the rhythm cycle is significantly shorter In 24 hours, usually less than 20h, which can be hours, minutes, or even seconds; (3)