1.   Indeed, there were fewer patients than expected taking NSAIDs, perhaps since intake had been reduced because of chronic duodenal ulcer disease.

2.   It is therefore concluded that this chronic ulcer is a model of imapred duodenal defence.

3.   The main, unsolved clinical problem is chronic duodenal ulcer.

4.   There is a new animal model that seems promisingly similar to chronic duodenal ulcer in man.

5.   No other model of chronic ulcer shows such morphological and behavioural similarity to the human duodenal ulcer.