Dr. John Hansen, Who Made Marrow Transplants Safer, Dies at 76

Dr. John A. Hansen, an immunologist whose pioneering research made bone marrow transplants safer and vastly expanded the pool of potential donors to patients with leukemia and other blood disorders, died on July 31 at his home in Mercer Island, Wash. He was 76. The cause was pancreatic cancer, his wife, Suzanne Hansen, said. As…