Natural history studies: their critical role.
Logemann
J A
JA
D000978:Antiparkinson Agents / Q000627:therapeutic use*; D003680:Deglutition Disorders / Q000209:etiology; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D010300:Parkinson Disease / Q000150:complications / Q000188:drug therapy*; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use*
D000978:Antiparkinson Agents; D007980:Levodopa; D010959:Tissue Plasminogen Activator