Oxygen, an important pharmacologic agent.
D001784:Blood Gas Analysis; D049669:History, 16th Century; D049670:History, 17th Century; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D010102:Oxygen Inhalation Therapy / Q000266:history* / Q000295:instrumentation