【摘要】 为了研究+Gz重力作用下脑循环的改变,10名被试者在半径为6米的人体离心机上承受了+G_Z超重作用。实验记录了心电、上臂血压、心振动图和脑阻抗图。发现,随着超重值的增加,心率、心输出量、上臂血压和外周循环阻力逐渐增大,计算得到的头部眼水平的平均动脉血压逐渐下降,脑阻抗图波高和波形发生明显改变。并对重要的生理指标和脑循环调节机制进行了分析和讨论。结果表明,尽管机体内存在许多补偿机制,但在G值较高时,由于不能完全代偿血液静水压效应的影响,脑循环还是可能发生明显的改变。更多还原

【Abstract】 In studying the cerebral circulatory changes under +Gz stress, ten healthy young men(18-24 yrs.) were exposed to + Gz stress on a human centrifuge with six meter radius. EEG,upper arm blood pressure, vibrocar-diogram and rheoencephalogram were recorded.lt was found that heart rate,upper arm blood pressure,cardiac output and periphery circulatory resistance increased,and amplitude and shape of rheoencephalogram chan- ged with the increase of +Gz. Changes of some important physoijogical parameters and the regulatory mechanisms of cerebral circulation under +Gz stress were analyzed and discussed. Results showed that in spite of existance of the various compensatory mechanisms, impairment of the cerebral circulation still occurred due to the hydrostatic effect of the blood column at higher G levels.更多还原