title: Cimetidine, ranitidine, and the heart rate.
mesh_terms: D002927:Cimetidine / Q000494:pharmacology*; D002986:Clinical Trials as Topic; D004311:Double-Blind Method; D004562:Electrocardiography; D005663:Furans / Q000494:pharmacology*; D006146:Guanidines / Q000494:pharmacology*; D006339:Heart Rate / Q000187:drug effects*; D006801:Humans; D008875:Middle Aged; D011897:Random Allocation; D011899:Ranitidine
chemical_list: D005663:Furans; D006146:Guanidines; D002927:Cimetidine; D011899:Ranitidine