title: Risus sardonicus and laughing gas--when nitrous oxide lost its innocence.
authors.affiliation: Department of Infectious Diseases, Blegdam Hospital, University of Copenhagen, Denmark.
authors.forename: H
authors.initials: H
authors.lastname: Sund Kristensen
authors.forename: P G
authors.initials: PG
authors.lastname: Berthelsen
mesh_terms: D000769:Anesthesia, Inhalation / Q000266:history*; D049671:History, 18th Century; D049672:History, 19th Century; D049673:History, 20th Century; D006801:Humans; D009609:Nitrous Oxide / Q000009:adverse effects / Q000266:history*
chemical_list: D009609:Nitrous Oxide