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  3. Athletes who cheat by injecting themselves with stored supplies of their own blood might soon be caught out. A revealing trail o

Athletes who cheat by injecting themselves with stored supplies of their own blood might soon be caught out. A revealing trail o

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问题     Athletes who cheat by injecting themselves with stored supplies of their own blood might soon be caught out. A revealing trail of debris could give the game away.
    Most "blood dopers" cheat by injecting themselves with the blood-boosting hormone erythropoietin(EPO), but there have been tests to detect EPO since 2000. Another way to dope blood is to periodically extract some of your own, store it and re-inject it before competitions. Some professional cyclists are alleged to have done this as part of a doping scandal that emerged in Spain in 2006, called Operacion Puerto. At least one cyclist is still fighting to clear his name.
    Re-injecting stored blood boosts the oxygen supply to muscles. The practice has so far eluded detection but now there might be a way catch out the cheats.
    During storage, red blood cells start to fall apart, generating debris such as the fragments of cell membranes(a cell membrane is the outside envelop of a living cell). Olaf Schumacher of the University of Freiburg in Germany and his colleagues have shown that when stored blood is re-injected, the recipient’s white blood cells prepare to get rid of this sudden tide of debris. They say that these changes on blood cell ’debris’ could betray sportsmen and make cheats detectable. "It’s like someone dumping rubbish in your blood," he says. "When all the rubbish comes at once, there’s lots of activity."
    Schumacher’s team took blood from six non-athletes, stored it for 35 days then re-infused it, taking further blood samples three and four days afterwards. When they analyzed the white blood cells in these samples, genes needed for identifying and disposing of ailing and damaged cells were much more active than usual.
    The gene changes led to the appearance of new proteins on the surface of the white blood cells which could potentially be picked up by antibodies, Schumacher says. He also suggests that antibodies could be created to detect the changes to the surface of red blood cells as well. Schumacher couldn’t say whether such tests would be ready in time for the 2012 Olympics in London. David Cowan, director of the UK Drug Control Centre at King’s College London, says: "The paper is promising, but more work is needed to establish a test that meets the rigorous standards required by sport so as not to falsely accuse an athlete." Schumacher says that one key goal is to make sure these changes only occur due to doping, rather than illness, for example.
Which kind of "blood dopers" is least likely to be detected in the past?
选项 A、People who inject themselves with EPO.
B、People who extract and re-inject some of their own blood.
C、People who took part in cycling competition in Spain in 2006.
D、People who are careful enough to avoid detection.
答案B
解析 事实细节题，考查是非细节。第三段第二句讲到，长久以来，这种做法(re-injecting stored blood)一直无法被检查出来，B项符合文意。
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