【摘要】 观察了头低位-15°、90min卧床条件下头颈部血液循环的变化特点。被试者为14名健康男性青年（18～21岁）。用超声多普勒血流仪测量了被试者在水平卧位和头低位时的颈总动脉血流量血流速度和管径等。结果表明，头低位时颈动脉血流量的变化存在较大的个体差异。根据颈动脉血流量的变化特点将被试者分为适应组（9人）与不适应组（5人）。与水平卧位相比较，在头低位时适应组颈动脉血流速度明显减慢、颈动脉管径扩张、头颈部循环阻抗增加，从而使颈动脉血流量保持在水平卧位时对照值附近，说明通过自身调节头部血液循环达到一个新的平衡状态。而不适应组的颈动脉血流量较水平卧位时有较大增加。结果提示，通过观察头低位时的颈动脉血流速度、管径、流量以及循环阻抗的变化趋势，可以评价人体心血管系统对失重状态下体液从心脏以下区域向头部区域重新分布的适应能力。更多还原

【Abstract】 In order to investigate the response of carotid blood flow to weightlessness,the subjects(14 healthy youngmen,aged 18~21 years)underwent - 15° head-down tilt for 90 min with their com-mon carotid blood flow measured by QFM-SYSTEM 1000 Doppler Volume Meter. The results showedthat the changes of carotid blood flow during head-down tilt varied in different individuals and the sub-jects may be divided into adaptive (9 out of 14) and inadaptive (5 out of 14) groups accordingly. Inadaptive group, carotid blood flow velocity was reduced, vessel diameter expanded and head-neck circu-latory impedance increased, so that the carotid blood flow volume was not significantly increased incomparison with that during lying horizontally, while in inadaptive group carotid blood flow volume wassignificantly increased. The results suggested that carotid blood flow volume can be used as an indey forevaluating the adaptability of cardiovascular system to weightlessness.更多还原