title: Heavy smokers, smoking cessation, and clonidine.
mesh_terms: D000279:Administration, Cutaneous; D003000:Clonidine / Q000008:administration & dosage*; D006801:Humans; D009538:Nicotine; D012907:Smoking / Q000188:drug therapy*
chemical_list: D009538:Nicotine; D003000:Clonidine