Dr. Joseph E. Murray, the Nobel laureate who conducted the world's first successful organ transplant, died Monday at the Boston hospital where the pioneering surgery was performed. He was 93. On Dec. 23, 1954, in Operating Room 2 of the Peter Bent Brigham Hospital in Boston, Dr. Murray took the healthy kidney of Ronald Herrick and sutured it into the donor's dying identical twin, Richard. With that 5½-hour operation, Dr. Murray and his team saved a life, sparked an ethical debate that still echoes today, and opened medicine to a new frontier. Murray, who focused on plastic and reconstructive surgery for most of his career, was recognized with the Nobel Prize in Medicine in 1990.