听力原文
Sleeping tight could be bad for your kidneys
Good news for restless sleepers －－researchers at the University of California tell us that kidney stones could be caused by sleeping too long in one position．Over ７５percent of people with recurrent kidney stones who always slept on one side got stones on that side of the body．This led the researchers to suggest that if the person stays in one position，the blood flow can become sluggish1) and stones（made from substances including calcium2） and magnesium3)）may then form．
参考译文
睡姿不变对肾有害
对睡眠中不太安稳的人来说，这是个好消息：加利福尼亚大学的研究者告诉我们，长时间保持一个睡姿可能会导致肾结石。７５％以上患有复发性肾结石且睡姿总是保持一个方向的人，极易在被身体压迫的那一侧产生结石。研究人员对此的解释是，如果你总是保持一个姿势，血流将不畅通，进而可能会导致结石（由钙和镁等物质组成）产生。
NOTE 注释：
sluggish [5slQ^iF] adj. 行动迟缓的
calcium [5kAlsiEm] n. [化]钙(元素符号Ca)
magnesium [mA^5ni:zjEm] n. [化]镁
