体位改变和昼夜节律对大脑血流速度的影响

Effect of body Position Changes and Circadian Rhythm on Cerebral Blood Flow Velocity.

为研究头低位倾斜（ＨＤＴ）、直立位和昼夜节律对大脑血流速度的影响，采用经颅多普勒（ＴＣＤ）新技术在上述三种情况下对１２名青年健康男性的脑血流速度进行了观察。结果显示：－６°头低位倾斜１ｈ后大脑中动脉血流速度增加；直立位１５ｍｉｎ后大脑中动脉血流速度降低；在昼夜２４ｈ中，夜间睡眠时大脑中动脉血流速度较白天低；ＴＣＤ技术重复性好。

To study the effects of -6° head down tilt(HDT), upright posture and 24 h circadian rhythm on cerebral blood flow(CBF)velocity in humans,the CBF velocity was measured by use of transcranial Doppler technique in the middle cerebral artery (MCA) of 12 healthy male subjects. The results showed that the mean CBF velocity increased significantly during -6° HDT and decreased during upright posture,and CBF velocity was higher in day time than at night.