The distal and narrowest portion of the SMALL INTESTINE, between the JEJUNUM and the ILEOCECAL VALVE of the LARGE INTESTINE.
D012007
Rectum
The distal segment of the LARGE INTESTINE, between the SIGMOID COLON and the ANAL CANAL.
Rectums
D003093
Colitis, Ulcerative
Inflammation of the COLON that is predominantly confined to the MUCOSA. Its major symptoms include DIARRHEA, rectal BLEEDING, the passage of MUCUS, and ABDOMINAL PAIN.