title: Pain: introduction.
mesh_terms: D003142:Communication; D049669:History, 16th Century; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D049690:History, Ancient; D049691:History, Medieval; D006801:Humans; D010146:Pain / Q000266:history / Q000503:physiopathology; D059408:Pain Management; D012106:Research; D012108:Research Personnel