| 摘要 |
<p>The present invention relates to an assay for evaluating alveolar exchange of oxygen. A 13C-labeled substrate, such as13C-sodium bicarbonate is administered to a subject by oral or iv intake, and exhaled 13CO2 is measured. The 13CO2 in expired breath can be collected at various time points following administration of the substrate and measured in ? per mil with a mass analyzer or photometer, such as an IR spectrometer. This process can be used as a diagnostic test for the indication of, treatment and/or evaluation of the severity of respiratory tract diseases or infections.</p> |
