I<br >The First of<br >July<br >First knife."<br > It was slapped into my hand.<br > I pressed the io-cm scalpel lightly into the stub-<br >bly skin just above the pubic bone and drew it smoothly across<br >t~e prominent bulge in the patient s groin. The bright blood<br >boiled up along the line of incision. Bill DeLeo， my resident，<br >d~bed it awa~<br > I continued cutting to expose the protruding bowel. As I<br >suspected， we had a real problem. Instead of being pink and<br >glistening， the bowel was black and dead.<br > "Gangrene，" Bill said. "We ll have to do a resection."<br > "I m afraid so." The mask muffled my words， but it couldn t<br >hide the apprehension in my voice. It meant at least another<br >hour on the table， an hour that might easily kill this patient.<br > His name was John M.， a seventy-four-year-old black man<br >who had arrived in the Emergency Room several hours be-<br >fore， complaining of abdominal pains. He was feverish and in<br >great agony. His groin was swollen and tender; his abdomen<br >distended. I listened for bowel sounds， but all I heard was an<br >ominous silence.<br > There was little doubt about the diagnosis: he had a bowel<br >blockage of some kind. The problem was to determine if I<br ><br >