title: [Relatively difficult clinical electrocardiograms].
mesh_terms: D000787:Angina Pectoris / Q000175:diagnosis; D003864:Depression, Chemical; D004071:Digitalis Glycosides / Q000494:pharmacology; D004562:Electrocardiography; D006321:Heart / Q000187:drug effects; D006327:Heart Block / Q000175:diagnosis; D006801:Humans; D009203:Myocardial Infarction / Q000175:diagnosis
chemical_list: D004071:Digitalis Glycosides