The hospitalized former shah of Iran, weakened by cancer and battling a typhoid infection, was placed in intensive care again today following an apparent deterioration in his condition.

A medical bulletin released by the specialists treating Mohammad Reza Pahlavi in Maadi Military Hospital said he was "under medical control."

Medical sources independent of the team of physicians treating him but familiar with his case said this was an indication his condition has become "more serious."

Other medical sources said the deposed shah underwent an emergency operation today to remove and replace a tube that was supposed to drain infection from his abdomen.

"Attending doctors faced a critical situation because his temperature continued to remain high and no fluids were coming through the tube," one of the sources said.

The doctors decided to take out the tube, clean it and insert it again. It was the 60-year-old former ruler's second operation in a week.

The shah underwent surgery last Monday for removal of the infection in the upper abdomen and chest cavity below the left lung.

Doctors had hoped it would bring down the shah's temperature, but it did not, so they decided to replace the tube in order to drain any pus that was left over since last Monday's surgery, the sources said.

One source called it a minor procedure, but the shah's condition was said to remain critical.

The official medical bulletin mentioned the shah's previous two operations in the same hospital but did not refer to any operation today.

The shah's spokesman and Egyptian officials said they had no knowledge of reported preparations for a burial place for the shah at a mausoleum next to Cairo's Al Rifiaie Mosque. The shah's father, shah Reza Pahlavi, was interred there temporarily during World War ii.

But there were noticeable signs of activity at the mosque. A back lawn neglected for years has been replanted and fenced with barricades. similar to those used by police for crowd control. The mausoleum wing of the mosque overlooks the lawn. An alley between the lawn and the mausoleum entrance has been covered with asphalt.