A PIECE OF MY MIND, edited by Bruce B. Dan & Roxanne K. Young (Ballantine: $4.95). It's easy to see why the column "A Piece of My Mind" is the most widely read feature of the Journal of the American Medical Assn. These first-person accounts by doctors, nurses and patients reveal the pathos that underlies the seemingly sterile world of medicine. Doctors complain about the physically and emotionally exhausting demands of internship, recall the trauma of the first death they had to witness and reminisce about proud but impoverished patients who paid for their care with firewood or home-made apple strudel. Some of the more serious essays confront questions surrounding the right to die; how to deal with the birth of a severely deformed infant; the problems of providing humane care for AIDS patients. These subjects have provided material for countless movies and TV shows, but the immediacy of these accounts gives them new urgency.