2019年翻译资格考试初级笔译模拟题：减肥药

　　科学家们已经研制出了一种减肥药，它能有效地抑制食欲，导致体重显著下降而无任何明显的不良反应。该药能干扰脑中的食欲控制系统，并阻止脂肪组织的积聚。服药的试验用小鼠减少的体重高达其体重的三分之一。在给小鼠服用被叫作C75的减肥药之后20分钟内，这些小鼠失去了进食的兴趣，仅满足于其正常进食量的10%生存。更重要的是，该药似乎能阻止代谢率的严重下降。代谢率的下降通常会引起疲劳乃至昏睡，这是以处于饥饿状态的饮食来维持生命时所出现的典型现象。实验结果显示，服用该药的小鼠于喂给相同数量食物的小鼠相比，其体重下降了45%以上，但后者则变得比较懒怠，即以减少活动量的方法来为“脂肪酸合酶”的一种酶结合在一起。这种酶参与了把过量的食物摄取转化成脂肪储存起来的过程。对这种酶的抑制导致在肝脏中产生一种化学物质，该物质是预示脂肪沉积的先兆，被认为会对脑产生一种的作用，从而抑制食欲。在正常情况下，当动物节制饮食时，一种被称为神经肽Y的激素就在脑的食欲控制中心急剧增加，从而刺激食欲。然而，当给动物服用了C75时，该激素就下降，使其失去对食物的兴趣。

　　参考译文

　　Scientists have developed a slimming drug that successfully suppresses appetite and results in a dramatic loss of weight without any apparent ill effects. The drug interferes with appetite control and prevents the build-up of fatty tissue. Laboratory mice given the drug lost up to a third of their total body weight. Within 20 minutes of being given the drug, called C75, the mice lost interest in eating and survived apparently content on just 10 percent of the food they would normally eat. More importantly, the drug appears to prevent a serious decline in metabolic rate—causing tiredness and lethargy—which is typically associated with living on a starvation diet. As a result, mice taking the drug lost 45 percent more weight than mice fed the same amount of food, which compensate for the lack of food by becoming more sluggish. The scientists believe that C75, which they produced synthetically in the laboratory, binds to an enzyme called fatty acid synthase, which is involved in storing excess food in take as fat. Inhibiting the enzyme caused a build-up of a chemical in the liver which acts as a precursor to fat deposition. This precursor is thought to have an indirect effect on the brain, causing appetite suppression. Normally, when animals fast, a hormone called neuropeptide Y increases sharply in the appetite-control centers of the brain, stimulating the desire for food. However, when animals are given C75, levels of this hormone fall, leading to a loss of interest in food.