title: Multiwavelength analyses of derivative spectra: an application for the determination of urinary porphyrins.
mesh_terms: D000328:Adult; D001663:Bilirubin / Q000494:pharmacology; D002848:Chromatography, DEAE-Cellulose; D006454:Hemoglobins / Q000494:pharmacology; D006801:Humans; D011166:Porphyrins / Q000652:urine*; D013053:Spectrophotometry
chemical_list: D006454:Hemoglobins; D011166:Porphyrins; D001663:Bilirubin