国际空间站上的空间生命科学研究与进展

Space Life Science Researches Aboard International Space Station

第一批长期考查组进驻国际空间站(ISS)开始长期载人飞行活动,揭开了人类航天史上崭新的一页,迄今已成功完成14批长期考查组飞行任务。在航天飞行中,航天员受到微重力、辐射、昼夜节律变化、隔离等异常环境因素的影响。为保障航天员长期飞行的健康,在ISS上已开展或将要开展的空间生命科学研究共计59项。这些研究探讨了长期失重引起骨皮质下骨质丧失与恢复的速度,骨骼肌萎缩与功能降低的特点,脊髓兴奋性降低,以及免疫功能降低与病毒再度活化的关系。另外,亦观察了长期隔离导致航天员心理与行为的变化,昼夜快速转换对睡眠的影响,并发现长期辐射可能引起白内障与肿瘤,也可能导致生殖、神经系统的损害,甚至会诱发遗传性病变。同时在飞行过程中检验了药物、运动、营养与振动等对抗措施的有效性,并进一步观测这些对抗措施对不同系统的防护效果。这些研究结果为发展新一代、针对性更强的对抗措施奠定了坚实基础。

The launch of Expedition 1 to the International Space Station （ISS） opened a new era in the history of human space flight, so far fourteen Expeditions had been achieved. But the astronauts were exposed to abnormal environment such as microgravity, radiation, isolation, confinement, and misalignment of circadian rhythm during space flight. In order to reduce health risks incurred by living in space, the 59 projects have been or will be studied aboard ISS. Those researches has elucidated the rate of subregional bone loss and its recovery, characteristics of atrophy and reduced contraction function in antigravity skeletal muscle, decrease in spinal cord excitability, and relationship between reduced immune function and reactivation of some viruses. The psychological and behavior changes in a prolonged isolation and confinement condition, as well as the fast circadian rhythm inducing sleep disruption has been observed. It has been found exposure to radiation not only causing cataracts and cancers, but also damaging the reproductive organs and nervous system, and inducing genetic damage. The efficacy of countermeasures of medicine, nutrition and vibration have been validated aboard the ISS. The effective countermeasures on different systems were checked further. All of those studies and observations have made a solid foundation for developing novel countermeasures which will be more effective.