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  3. Helicobacter pylori is one of humanity’s oldest and closest companions, and yet it took scientists more than a century to recogn

Helicobacter pylori is one of humanity’s oldest and closest companions, and yet it took scientists more than a century to recogn

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问题     Helicobacter pylori is one of humanity’s oldest and closest companions, and yet it took scientists more than a century to recognize it. As early as 1875, German anatomists found spiral bacteria colonizing the mucus layer of the human stomach, but because the organisms could not be grown in a pure culture, the results were ignored and then forgotten. It was not until 1982 that Australian doctors Barry J. Marshall and J. Robin Warren isolated the bacteria, allowing investigations of H. pylori’s role in the stomach to begin in earnest. Over the next decade, researchers discovered that people carrying the organisms had an increasing risk of developing peptic ulcers-breaks in the lining of the stomach or duodenum and that H. pylori could also trigger the onset of the most common form of stomach cancer.
    Just as scientists were learning the importance of H. pylori, however, they discovered that the bacteria are losing their foothold in the human digestive tract. Whereas nearly all adults in the developing countries would still carry the organism, its prevalence is much lower in developed countries such as the U S. Epidemiologists believe that H. pylori has been disappearing from developed nations for the past 100 years thanks to improved hygiene, which blocks the transmission of the bacteria, and to the widespread use of antibiotics. As H. pylori has retreated, the rates of peptic ulcers and stomach cancer have dropped. But at the same time, diseases of the esophagus—including acid reflux disease and a particularly deadly type of esophageal cancer—have increased dramatically, and a wide body of evidence indicates that the rise of these illnesses is also related to the disappearance of H. pylori.
Which of the following would most probably follow the last sentence of this passage?
选项 A、Furthermore, the disappearance of H. pylori may be a sentinel indicating the possibility of other microbial extinctions as well.
B、The possibility that this bacterium may actually protect people against disease of the esophagus has significant implications.
C、However, there has been an unexpected rise in the incidence of a new class of diseases involving the esophagus.
D、The rise of these diseases has occurred just as H. pylori has been disappearing, and it is tempting to associate the two phenomena.
答案B
解析 根据第二段的最后一句话可知，一些食道疾病与幽门螺旋菌存在相关性，因而接下来自然会想到幽门螺旋菌可能会防止产生食道疾病。即选项B“这种细菌实际上可能会保护人们免于食道疾病，这有着重要的意义”是最有可能的后续语，故正确答案为B。
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