• 2012年职称英语测验综合类专项演习:浏览辨别
  • 发布时间:2020-05-19 01:01 | 作者:admin | 来源:原创 | 浏览:1200 次
  •   2012年4月7日的职称英语测验一天一天邻近,广阔考生要抓紧时间温习了,小编为大年夜家整顿了职称英语专项演习,祝大年夜家测验顺利过关。

      Dangers await babies with altitude 高海拔的婴儿有风险

      Women who live in the world's highest communities tend to give birth to under-weight babies, a new study suggests. These babies may grow into adults with a high risk of heart disease and strokes.

      Research has hinted that newborns in mountain communities are lighter than average. But it wasn't clear whether this is due to reduced oxygen levels at high altitude or because their mothers are under-nourished — many people who live at high altitudes are relatively poor compared with those living lower down.

      To find out more, Dino Giussani and his team at Cambridge University studied the records of 400 births in Bolivia during 1976 and 1998. The babies were born in both rich and poor areas of two cities: La Paz and Santa Cruz. L Paz is the highest city in the world, at 3.65 kilometers above sea level, while Santa Cruz is much lower, at 0.44 kilometers.

      Sure enough, Giussani found that the average birthweight of babies in La Paz was significantly lower than in Santa Cruz. This was true in both high and low-income families. Even babies born to poor families in Santa Cruz were heavier on average than babies born to wealthy families in lofty La Paz. "We were very surprised by this result," says Giussani.

      The results suggest that babies born at high altitude are deprived of oxygen before birth. "This may trigger the release or suppression of hormones that regulate growth of the unborn child," says Giussani.

      His team also found that high-altitude babies tended to have relatively larger heads compared with their bodies. This is probably because a fetus starved of oxygen will send oxygenated blood to the brain in preference to rest of the body.

      Giussani wants to find out if such babies have a higher risk of disease in later life. People born in La Paz might be prone to heart trouble in adulthood, for example. Low birthweight is a risk factor for coronary heart disease. And newborns with a high ratio of head size to body weight are often predisposed to high blood pressure and strokes in later life.

      译文:

      一个新的研究标明住活着界高海拔地区的女人平日生下体重缺少的婴儿。这些婴儿在长大年夜成人后得心脏病和中风的风险很大年夜。

      研究暗示在山区出身的更生儿低于平均体重。然则还不清晰这是因为在高海拔的中央氧气缺少,照样因为他们的母亲没有取得足够的营养——很多住在高海拔中央的人相对都比住在低处的人穷。

      为了了解更多的状况,剑桥大年夜学的迪诺·吉萨尼和他的团队研究了1997年到1998年玻利维亚的400个更生儿的记录。这些婴儿出身于两个城市的富有和贫困地区:拉帕兹和散塔克鲁兹。拉帕兹是世界上最高的城市,海拔3.65千米,而散塔克鲁兹低很多,海拔440米。

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