born April 23, 1867, Silkeborg, Den.
died Jan. 30, 1928, Copenhagen
Danish pathologist.
He found that rats that had suffered stomach-tissue inflammation caused by the larvae of a worm infecting cockroaches the rats had eaten subsequently developed stomach tumours, and he induced tumours in mice and rats by feeding them infected cockroaches. His work, for which he received a 1926 Nobel Prize, supported the prevailing concept that cancer is caused by tissue irritation and led to production of chemical carcinogens for use in cancer research.