An aspiring missionary doctor, who was voted by medical school classmates as the epitome of a good physician, was killed Saturday at Christus St. Joseph Hospital when an elevator malfunctioned, decapitating him, authorities said. Hitoshi Nikaidoh, 35, of Dallas, a surgical resident at the hospital at 1919 La Branch, was stepping onto a second-floor elevator in the main building around 9:30 a.m. when the doors closed, pinning his shoulders, said Harold Jordan, an investigator with the Harris County Medical Examiner's Office. The elevator car then moved upward, severing the doctor's head, Jordan said. "It is an unexpected and tragic loss,"...