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一、综述六十年代初,美国曾提出《阿波罗登月飞船》计划,经过约十年的努力,把人送上了月球。七十年代初,又制订了《航天飞机》计划。目前,航天飞机也曾三次成功地进行了轨道试飞。但是,下一步美国空间计划的重点将转移到哪个方面呢?下面简单谈谈这 相似文献
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Artificial gravity: a possible countermeasure for post-flight orthostatic intolerance 总被引:1,自引:0,他引:1
Moore ST Diedrich A Biaggioni I Kaufmann H Raphan T Cohen B 《Acta Astronautica》2005,56(9-12):867-876
Four payload crewmembers were exposed to sustained linear acceleration in a centrifuge during the Neurolab (STS-90) flight. In contrast to previous studies, otolith–ocular reflexes were preserved during and after flight. This raised the possibility that artificial gravity may have acted as a countermeasure to the deconditioning of otolith–ocular reflexes. None of the astronauts who were centrifuged had orthostatic intolerance when tested with head-up passive tilt after flight. Thus, centrifugation may also have helped maintain post-flight hemodynamic responses to orthostasis by preserving the gain of the otolith–sympathetic reflex. A comparison with two fellow Neurolab orbiter crewmembers not exposed to artificial gravity provided some support for this hypothesis. One of the two had hemodynamic changes in response to post-flight tilt similar to orthostatically intolerant subjects from previous missions. More data is necessary to evaluate this hypothesis, but if it were proven correct, in-flight short-radius centrifugation may help counteract orthostatic intolerance after space flight. 相似文献
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Investigations of Mir, Space Shuttle, Skylab and Apollo missions report extensive colonisation of the spacecraft by bacteria and fungi, which can lead to degradative effects on spacecraft equipment and devastating effects on space-grown crops. More than 80% of terrestrial greenhouse epidemics are due to the fungal genera Phytophthora, Pythium and Fusarium, which have been found in life support system test-beds. The advent of recombinant antibody technologies, including ribosome display and phage display, has made it possible to develop antibodies against virtually any toxin or organism and allows for maturation of antibodies by in vitro molecular evolution. These antibodies may play an important role in an integrated pest management regime for life support systems. Efficacy of existing fungal countermeasures could be increased by chemical linkage to antibodies, which target the site of action of the biocide or trap the pathogen in a biofilter. Novel recombinant antibody-biocide fusions can be expressed in situ by plants or symbiotic microbes to create direct disease resistance. 相似文献
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