摘要
失重生理效应的层次特征魏金河（北京航天医学工程研究所１０００９４）人类长期生存在地球表面，适应于地球的引力作用。一旦进入空间飞行的失重状态，人体的生理系统就不可避免地发生一系列适应性变化。由于重力作用的普遍性，失重的生理效应必然涉及从分子、细胞到整体...
The effects of
weightlessness on physiological system were categorizedinto threc types :(1) induced by
sensory information changes (Type 1);(2 ) caused bybody fluid-shift(Type 2 );(3 ) direct
mechanical effects(Type 3 ). Type 1 effects areresponses at the level of whole body , which
involves mainly the changes of sensorimotorperformance especially the spatial orientation
control , among whiCh the most serious ef-fect is the occurence of space motion sickness. The
essential process of Type 1 responses isremodeling of the sensorimotor matching mode ,
which is called as the Central Remodel-ing. Type 2 responses are at the system level which
mainly include the systems related in-ternal environmental homeostasis. Establishing new
steady state is the important charac-teristics of Type 2 responses. Type 3 effects are at the
tissue or cell level, such as boneand fnuscle , of which the prominent feature is the long lasted
deteriorative changes whileweightlessness exists.Incidentally , the durations of adaptation
process for the three types of effects are ap-parently different : days for Type 1, weeks for Type
2 and months for Type 3. There-fore,it is hypothesized that the higher the level at which the
effect of weightlessness oc-curs , the shorter the duration of adaptation process. There are key
points in the proposedtheory : The higher level system possesses stronger regulation ability
and is less dependentupon the performance change of it’s subsystem or elements; The
speed of remodeling isfast for software and slow for hardware.Interestingly , asymmetrical
phenomena are common for all the three types of ef-fects : the durations are shorter for
readaptation to 1-G than adaptation to weightlessness,but more obvious for lower level effects.
To explain these asymmetrical phenomena,memory effects are proposed to exist at cellular or
molecular levels. The possible directeffects of weightlessness on cells or macro- molecles are
challenging the life scientists withmany opportunities
出处
《航天医学与医学工程》
CAS
CSCD
1994年第2期134-139,共6页
Space Medicine & Medical Engineering
关键词
失重
生理效应
层次特征
physiological effects of
weightlessness , central remodeling , system analy-sis ,adaptation and readaptation
