title: Problems in standardization of digitalis-like substance assays by means of competitive immunological methods.
mesh_terms: D001798:Blood Proteins / Q000032:analysis*; D002298:Cardenolides; D004077:Digoxin; D006801:Humans; D007118:Immunoassay; D011786:Quality Control; D012503:Saponins
chemical_list: D001798:Blood Proteins; D002298:Cardenolides; D012503:Saponins; C034504:digoxin-like factors; D004077:Digoxin