title: Letter: Duration of action of practolol.
mesh_terms: D005080:Exercise Test; D006207:Half-Life; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D009203:Myocardial Infarction / Q000517:prevention & control; D010919:Placebos; D011217:Practolol / Q000008:administration & dosage / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D010919:Placebos; D011217:Practolol