title: Comparison of sampling methods for the analysis of methane in expired air.
mesh_terms: D000293:Adolescent; D000328:Adult; D001944:Breath Tests / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008697:Methane / Q000032:analysis* / Q000378:metabolism; D008875:Middle Aged; D013048:Specimen Handling / Q000379:methods*
chemical_list: D008697:Methane