Leach M O, Bell C M, Thomas B J, Dabek J T, James H M, Chettle D R, Fremlin J H
Phys Med Biol. 1978 Mar;23(2):282-90. doi: 10.1088/0031-9155/23/2/006.
A study has been made of the effect that different methods of breath collection have on the measurement of calcium in vivo by the 40Ca(n,alpha) 37Ar method. The effect of open and rebreathing breath collection methods has been examined by using intravenous injections of 133Xe. This study has indicated that comparison of calcium measurements between individuals and between centres is likely to be accurate only if breath is collected on 'open circuit'.
一项关于不同呼气收集方法对通过40Ca（n，α）37Ar方法进行体内钙测量的影响的研究已经展开。通过静脉注射133Xe来检验开放式和再呼吸式呼气收集方法的影响。这项研究表明，只有在“开路”状态下收集呼气，个体之间以及不同中心之间的钙测量结果比较才可能是准确的。
