the subgroup of patients with a duodenal ulcer who had healed on either treatment regimen had a symptomatic relapse significantly more frequently than those with prepyloric ulcer ( 64 % +/- 13 versus 34 % +/- 15 ; p less than 0.025 ) , but the estimated probabilities of relapse were unaffected ( p greater than 0.05 ) by the initial type of medication ( ranitidine group , 56 % +/- 15 ; antacid group , 51 % +/- 15 ) .
C0013295
duodenal ulcer
C0034665
ranitidine