Lewellen T K, Nelp W B, Murano R, Palmer H E, Hinn G M
Phys Med Biol. 1979 Jan;24(1):124-35. doi: 10.1088/0031-9155/24/1/010.
A technique to measure total body calcium using the 40Ca(n, alpha)37 Ar reaction has been developed. The technique is based on collecting 37Ar exhaled in the breath following a 10 mrad uniform total body irradiation by 14 MeV neutrons. The 37Ar in the exhaled breath is extracted by selective absorption and its radioactivity is measured inside a low-background proportional detector. The facilities developed include an activation facility providing a +/-2.7% activation uniformity, a closed circuit rebreathing and gas collection system, and a gas purification and counting system. The technique provides a precision of +/-2.4% as determined by repetitive measurements of human volunteers and has an accuracy for determination of total body calcium in grams of +/-5%.
已开发出一种利用40Ca(n,α)37Ar反应测量全身钙含量的技术。该技术基于在14兆电子伏特中子对全身进行10毫拉德均匀照射后，收集呼出气体中的37Ar。呼出气体中的37Ar通过选择性吸收提取，其放射性在低本底正比探测器内测量。所开发的设备包括一个提供±2.7%活化均匀性的活化设备、一个闭路再呼吸和气体收集系统以及一个气体净化和计数系统。经对人体志愿者的重复测量确定，该技术的精度为±2.4%，以克为单位测定全身钙含量的准确度为±5%。
