H substance - a precursor of A and B tissue isoantigens.
D000017:ABO Blood-Group System / Q000032:analysis / Q000096:biosynthesis*; D004386:Duodenum / Q000276:immunology; D006383:Hemadsorption Inhibition Tests; D006801:Humans; D010179:Pancreas / Q000276:immunology
D000017:ABO Blood-Group System