title: Simple and reliable gas-liquid chromatographic assay for underivatized theophylline in plasma using an organic-nitrogen specific detector.
mesh_terms: D001322:Autoanalysis; D001463:Barbiturates / Q000097:blood; D002849:Chromatography, Gas; D006801:Humans; D009584:Nitrogen; D013806:Theophylline / Q000097:blood*; D014970:Xanthines / Q000097:blood
chemical_list: D001463:Barbiturates; D014970:Xanthines; D013806:Theophylline; D009584:Nitrogen