Six hundred Boston doctors, medical students, and health workers joined forces yesterday to urge an end to the Vietnam war.

At a news conference in the Sheraton Plaza, spokesmen for the group said the doctors and students plan to stand on Boston street-corners and ask 185,000 passersby to sign postcards which will be mailed to the White House.

The postcards read: "Mr. Nixon: Forty thousand Americans are dead, and how many Vietnamese? Yet we spend $100 million a day killing even more. Bring our men and dollars back home so we can fight the real enemies-disease and human misery. Get us out within six months."

Astronomical

Dr. Henry Bakst, dean of the Boston University School of Medicine, said, "the cost of war has risen to astronomical heights and has reached a point at which expenditures for this purpose have begun to interfere seriously with health research and training programs."

Dr. John F. Enders, Nobel Laureate and University Professor, Emeritus at Harvard, said, "It is time to change our attitude and to try to get out quickly."

The doctors announced that some medical groups will march from hospitals Wednesday to join the afternoon rally at the Boston Common. Some doctors and students who cannot leave their work Wednesday will wear arm bands saying "Peace." A few hospitals will hold "peace vigils," showing documentary films on Vietnam.

A forum on "Vietnam and Health" will be presented at 8 p. m. today, in the Simmons College auditorium. Robert H. Ebert, dean of the Harvard Medical School, will be the moderator. Participants will include Dr. John H. Knowles '47, general director of Massachusetts General Hospital.