21.   She underwent surgery to remove a ureter and kidney as a result of the cancer and currently is receiving chemotherapy.

22.   Stressors can also be negative events, like dealing with an irate boss, getting stuck in traffic, or undergoing surgery.

23.   The cyclist underwent emergency surgery yesterday after a collision with a car.

24.   The President will undergo minor surgery today to remove a small growth from his finger.

25.   The procedure, Incidentally, can and has been performed on patients undergoing brain surgery.

26.   The swop did not come to light until Arlena, who suffered from a congenital heart defect, had to undergo surgery.

27.   The teenager underwent emergency surgery after a bullet pierced her lung.

28.   There are risks if you choose to undergo surgery.

29.   This view is strengthened by the fact that direct stimulation of the brain can produce sensory impressions in patients undergoing brain surgery.