【英语时差8,16】红头发人的抗痛力-下（在线收听）

Professor Daniel Sessler from the Cleveland Clinic in the United States is one of the authors of the study. He says the research is a considerable scientific breakthrough. "Red hair is the first phenotype of anaesthetic requirement in humans. And what I mean by phenotype is an external characteristic. "So lets say you are walking down the street and you see someone who's a little older and a little younger - that tells you nothing about their anaesthetic requirement. You see a man and a woman - that tells you nothing about their anaesthetic requirement. But you see a redhead - aha! You know that person is going to require 20 percent more general anaesthesia." From my own personal experience I would say that there is some merit to this idea. I have found that I have had to ask dentists for extra anaesthetic in the middle of procedures. Some dentists argue that a greater sensitivity to pain might actually benefit redheads and drive them to see the dentist more quickly. In my own case I can attest that is definitely not true.