title: Levodopa therapy effects on natural history of Parkinsonism.
mesh_terms: D000328:Adult; D000368:Aged; D004295:Dihydroxyphenylalanine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D005069:Evaluation Studies as Topic; D006801:Humans; D008134:Long-Term Care; D008875:Middle Aged; D009460:Neurologic Examination; D010300:Parkinson Disease / Q000188:drug therapy*; D010919:Placebos; D014202:Tremor
chemical_list: D010919:Placebos; D004295:Dihydroxyphenylalanine