2020托福听力练习：高脂饮食因肠道细菌致肥胖（下载）-新东方网

国际教育

□□

托福听力

2020托福听力练习：高脂饮食因肠道细菌致肥胖（下载）

2020-07-07 16:41

　　新东方网为大家带来2020托福听力练习：高脂饮食因肠道细菌致肥胖（下载），希望对大家有所帮助!更多内容请随时关注新东方网!

　　Think it's your inability to resist cheesecake that's making it tough to fit into your skinny jeans? Well, your bacteria may share some of the blame. Because a new study in mice shows that the response of intestinal microbes to a high-fat diet ends up triggering the release of a hormone that makes mammals feel hungry, causing them to eat even more. The finding is served up in the journal Nature.

　　Previous work has shown that the types of bacteria in the gut in diabetic or obese individuals are different from the bacteria in healthy people. But does this bacterial makeup contribute to these disorders? Or is it just a side effect?

　　To unravel this mystery, researchers put mice on a high-fat diet. The animals experienced a buildup of a chemical called acetate, particularly in the large intestine.

　　That location points to gut bacteria, which can produce acetate, as a possible culprit. So the researchers wiped out the microbes using antibiotics or a simple saline wash. And acetate levels plummeted.

　　Okay, so the gut bacteria in fat-fed mice make acetate. What does acetate do? Well, it gets the involuntary part of the nervous system, the parasympathetic nervous system, to put out the call to produce more insulin. Unfortunately, in this case, acetate also gets the parasympathetic nervous system to stimulate production of a hunger hormone called ghrelin. And the more fats an animal consumes, the more acetate it makes — which means the more ghrelin it produces and, of course, the more it eats. And bacteria make the whole sequence happen.

　　The researchers are now investigating whether the same biochemical events happen in humans. If they do, it's possible that obtaining a better assortments of gut bacteria could help us control our weight. Of course, the best way to get those good bacteria is from a fecal transplant — in which bacteria-rich feces come out of one person and into you. The very thought of which could help curb your appetite.

翻译见下页

　　设想一下，你很难穿上紧身牛仔裤是因为你无法抗拒奶酪蛋糕吗?其实，你体内的细菌可能要承担部分责任。一项在小鼠身上进行的新研究表明，肠道细菌对高脂饮食的反应会最终引发荷尔蒙的释放，使哺乳动物感到饥饿、吃得更多。该项发现刊登在《自然》杂志上。

　　此前的研究表明，糖尿病患者或肥胖群体肠道中的细菌类型与健康人的不同。但是这种细菌组成会导致这些疾病吗?还是只是一种副作用?

　　为了解开这个谜团，研究人员让小鼠食用高脂饮食。因此，醋酸酯这种化学物质在这些动物的大肠内积累起来。

　　该位置指向肠道细菌，这种细菌能产生醋酸酯，是潜在的罪魁祸首。因此，研究人员用抗生素或简单的生理盐水来消灭微生物。这同时也使醋酸酯浓度下降。

　　食用高脂饮食的小鼠，其体内肠道细菌可以产生醋酸酯。醋酸酯的作用是什么?它可以使神经系统、副交感神经系统中的无意识部分发出信号，产生更多的胰岛素。不幸的是，在这种情况下，醋酸酯也会使副交感神经系统刺激饥饿激素的产生。同时，脂肪消耗的越多，体内产生的醋酸酯就越多，这意味着体内产生的饥饿激素越多，当然就吃的越多。而且细菌会使这一整个序列发生。

　　研究人员正在研究相同的生物化学反应是否会在人类身上发生。假如人类也会这样，那么对肠道细菌更好的分类也许可以帮助我们控制体重。当然，摄取这些有益细菌的最佳方式是通过粪便移植，即某人含有大量细菌的排泄物进入到你的体内。想到这里可能会有助于抑制你的食欲。

　　重点讲解：

　　1. end up 最终;结果;到头来;

　　例句：If you speak too slowly, you might end up sounding unnatural.

　　但如果说得太慢，就有可能导致发音不自然。

　　2. be different from 与……不同;

　　例句：My style of writing is very different from yours.

　　我写作的风格和你很不同。

　　3. contribute to 促成;促使;是导致…的原因之一;

　　例句：Exercise contributes to better health.

　　锻炼能促成更强健的体魄。

　　4. wipe out 摧毁;毁灭;使灭绝;