摘要
目的 用单轴向离心机和下体正压模拟推拉动作 ,研究后倾座椅对推拉效应的影响。 方法 6名受试者在离心机上直座椅测基础耐力后 ,着 KH- 3抗荷服充气 30 0 m m Hg(1mm Hg=0 .133k Pa) 1m in,放气后立即转动离心机 ,测松弛 G耐力。然后将座椅后倾 45°重复。 结果 下体正压后 G耐力显著下降 (P<0 .0 1) ,采用后倾座椅后显著升高 (与对照相比 ,P<0 .0 1;与下体正压后相比 ,P<0 .0 5 )。后倾座椅在有和无预先下体正压的耐力之间有显著差别 ,预先有下体正压比无下体正压时显著低 (P<0 .0 1)。后倾座椅在预先有与无下体正压时提高的 G耐力分别为 0 .91± 0 .6 1和 1.17± 0 .30 ,差别无显著性意义 (P>0 .0 5 )。 结论 后倾座椅可以使推拉效应降低的 G耐力提高 ,但不能完全消除推拉效应。
Objective To explore the effect of reclined sitting position on push-pull effect simulated by human centrifuge run immediately after lower body positive pressure. Methods Six volunteers served as subjects. Their relax +G Z tolerance was measured sitting in a seat with upright seat back on the human centrifuge. After that they subjected to lower body positive pressure up to 300 mm Hg for 1 min, and +G Z tolerance was measured sitting in a seat with upright seat back on the human centrifuge immediately after the pressure was released. Then the seat back angle was adjusted to 45 degree, and the above procedure was repeated. Results As compared with the baseline +G Z tolerance in upright back seat, the G tolerance after LBPP decreased significantly (P< 0.01). When semi-reclined seat was used, +G Z tolerance without and with preceding LBPP was elevated by 1.17±0.30 and 0.91±0.61 G respectively, but the +G Z tolerance without preceding LBPP was still significantly higher than that with preceding LBPP (P<0.01). Conclusion Semi-reclined seat can elevate the lowered +G Z tolerance induced by push-pull effect and increase +G Z tolerance, however, the push-pull effect can't be eradicated by it.
出处
《中华航空航天医学杂志》
CSCD
2002年第1期8-10,共3页
Chinese Journal of Aerospace Medicine
关键词
加速度
后倾座椅
推拉效应
下体正压
Acceleration
Supine seat
Push-pull effect
Lower body positive pressure
