"60 MINUTES" LISTINGS FOR SUNDAY APRIL 20, 2008

AMBUSH IN AFGHANISTAN - U.S. Army Special Forces say they were shocked by the disciplined military tactics used by hundreds of Taliban fighters who ambushed them near Kandahar, Afghanistan, in their first account of the unreported battle. Lara Logan reports. Tom Anderson, Jenny Dubin and Max McClellan are the producers.

THE BYPASS EFFECT - An operation performed primarily to reduce weight in the obese has some startlingly positive side effects on type 2 diabetes, sleep apnea, high blood pressure, coronary artery disease and even cancer. Lesley Stahl reports. Shachar Bar-On is the producer.

THE LOST LEONARDO - The Leonardo DaVinci masterpiece, The Battle of Anghiari, is thought to be lost forever, but an art detective thinks he has solved the mystery of the missing mural. Morley Safer reports. David Browning is the producer.