1.   Normal mucosal biopsy specimens from three different locations of the upper gastrointestinal tract were taken during endoscopy from six dyspeptic patients without demonstrated pathology.

2.   Grossly normal appearing gastric biopsy specimens were taken from healthy volunteers.

3.   In the normal colonic biopsy specimens, two patients showed inappropriate staining with anti-B antibodies.

4.   The other five were histologically normal colonoscopic biopsy specimens taken from children investigated for abdominal pain.