The Ronald Reagan U.C.L.A. Medical Center, one of the nation's most highly regarded academic hospitals, has earned a reputation as a place where doctors will go to virtually any length and expense to try to save a patient's life. Yet that ethos has made the medical center a prime target for critics in the Obama administration and elsewhere who talk about how much money the nation wastes on needless tests and futile procedures. They like to note that U.C.L.A. is perennially near the top of widely cited data, compiled by researchers at Dartmouth, ranking medical centers that spend the most on end-of-life care but seem to have no better results than hospitals spending much less.