VATICAN CITY (AP) - Pope John Paul II told a group of doctors Saturday that resorting to extreme measures to try to keep alive the terminally ill at all costs does not respect the patient.

John Paul was addressing participants from a scientific congress on gastroenterology, a branch of medicine studying diseases of the stomach and the intestines.

The pontiff has familiarity with specialists from that field. Ten years ago, the pope had surgery to remove a bowel tumor his doctors said was close to turning cancerous.

While encouraging scientists to pursue research for new treatments, John Paul told his audience, "Certainly one cannot forget that man is a limited and mortal being."

"It's thus necessary to approach the ill with that healthy realism which avoids generating in those who suffer the illusion of medicine's omnipotence," the pontiff said. "There are limits which can not be humanly overcome."

Telling the doctors that caring for patients "must take into the account not only the body but also the spirit," John Paul said it was "presumptuous" to count just on scientific technique.

"And, in this perspective, extreme measures at all costs, even with the best intentions, would be, in the end, not only useless, but not fully respectful of the patient who has reached the terminal stage," the pontiff said.

John Paul, 81, who suffers from several ailments, has often shown much empathy with the ill.

His activities have been largely hampered by symptoms of Parkinson's disease, including a hand tremor and frequently slurred speech, and persistent knee pain led to the cancellation of several public appearances recently.

John Paul praised gastroenterologists' efforts to encourage good health through their recommendations of healthy daily habits and preventative, periodic medical examinations.

An editorial Saturday in the Vatican's newspaper, L'Osservatore Romano, said euthanasia "is not a human right proclaimed in the charters of states or in the declarations of international organizations. It is, in a proper and realistic sense, a crime, a crime against life."

John Paul has frequently spoken out against euthanasia. The latest denunciation came a day after a British judge ruled that a paralyzed woman who wants doctors to remove the ventilator keeping her alive has a right to die.

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