4 results match your criteria: "National Aeronautics and Space Administration Lyndon B. Johnson Space Center[Affiliation]"
FASEB J
September 2017
Human Health and Performance Directorate, National Aeronautics and Space Administration Lyndon B. Johnson Space Center, Houston, Texas, USA
During and after missions on the International Space Station, some astronauts experience ophthalmic changes, including choroidal folds, optic disc edema, cotton-wool spots, globe flattening, and refraction changes. Astronauts with ophthalmic issues had significantly higher plasma concentrations of metabolites that are associated with the 1-carbon metabolic pathway than those without ophthalmic issues. We hypothesized that genetic differences might explain the metabolite differences.
View Article and Find Full Text PDFBone
March 2008
Human Adaptation and Countermeasures Division, National Aeronautics and Space Administration Lyndon B. Johnson Space Center, Houston, TX 77058, USA.
Bone loss associated with disuse during bed rest (BR), an analog of space flight, can be attenuated by exercise. In previous studies, the efficacy of either aerobic or resistive exercise countermeasures has been examined separately. We hypothesized that a regimen of combined resistive and aerobic exercise during BR would prevent bone resorption and promote bone formation.
View Article and Find Full Text PDFMil Med
January 2000
Medical Operations Branch, National Aeronautics and Space Administration/Lyndon B. Johnson Space Center, Houston TX, USA.
In high-performance aircraft, the need for total environmental awareness coupled with high-g loading (often with abrupt onset) creates a predilection for cervical spine injury while the pilot is performing routine movements within the cockpit. In this study, the prevalence and severity of cervical spine injury are assessed via a modified cross-sectional survey of pilots of multiple aircraft types (T-38 and F-14, F-16, and F/A-18 fighters). Ninety-five surveys were administered, with 58 full responses.
View Article and Find Full Text PDFAm J Physiol
July 1999
Nutritional Biochemistry Laboratory, Life Sciences Research Laboratories, National Aeronautics and Space Administration Lyndon B. Johnson Space Center, Houston, TX 77058, USA.
The loss of bone during spaceflight is considered a physiological obstacle for the exploration of other planets. This report of calcium metabolism before, during, and after long-duration spaceflight extends results from Skylab missions in the 1970s. Biochemical and endocrine indexes of calcium and bone metabolism were measured together with calcium absorption, excretion, and bone turnover using stable isotopes.
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