【摘要】 目的　通过研究模拟失重情况下下肢顺应性的变化及双下肢静脉加压套带的影响 ,探讨模拟失重后立位耐力下降的机理和静脉加压套带防护作用的机理。　方法　 6名健康男性志愿者进行了两次 7d- 6°头低位卧床试验。第一次试验时 3名受试者卧床中使用双下肢加压充气套带 ,压力40 mm Hg,每天 8:0 0～ 2 0 :0 0使用 12 h;另 3名受试者不使用任何对抗措施。第二次试验时两组受试者互换。在卧床前和卧床第 7d进行的立位试验中测量了受试者右侧小腿截面积的变化 ;在卧床前、第6 d和起床后第 2 d应用静脉阻断法测量了在阻断压力分别为 2 0、30、5 0、70和 80 mm Hg时受试者右侧小腿截面积的变化。　结果　立位试验和静脉阻断法中较高阻断压力时 ,卧床后对照组下肢顺应性明显增加 (立位 10 min时 ,P<0 .0 5 ) ,而套带组有下降趋势。　结论　下肢顺应性的增加可能是模拟失重后立位耐力下降的原因之一 ;双下肢加压套带阻止头低位卧床后立位耐力的下降 ,部分是通过阻止下肢顺应性的增加而实现的更多还原

【Abstract】 Objective To explore the mechanism of the orthost atic intolerance after simulated microgravity and the mechanism of the preventiv e effects of thigh cuffs. Methods Six healthy male volunteers served as subjects. They underwent -6° head down tilt bed rest for 7 days twice . Thigh cuffs were used in 3 of the 6 subjects at the first time and in other 3 at the second time. Cuffs were put on at 8:00 and taken away at 20:00 every day during HDT with a pressure of 40 mm Hg. Standing test and venous occlusion metho d were used to measure the leg compliance of the subjects before and after the H DT. Results As compared with that before HDT, leg compliance i ncreased significantly after HDT in group without cuffs (standing test at 10 min , P<0.05). While in group with cuffs, it showed a tendency of lowering. Conclusion It is suggested that the increase of leg compliance con tributed partly to the orthostatic intolerance after HDT bedrest, while the prev entive effect of thigh cuffs on the occurrence of orthostatic intolerance after HDT bedrest is partly due to preventing the increase of leg compliance.更多还原