英语听力精选进阶版 7169

Background：科学家们最近在研究新一代的抗生素。这种抗生素将会使用一种在地球上存活了2亿多年的动物 – 青蛙。科学家们将从青蛙体内自身的抵抗系统里提炼出一种天然抗生素。

Frogs protect themselves by secreting¹ chemicals that kill germs on their skin. So the theory is that some of these chemicals could be used as antibiotics².

To find out, researchers in the United Arab Emirates asked colleagues across the world to swab any frogs they found and send them their secretions³. They received samples from more than six thousand different species and identified more than a hundred germ-killing chemicals.

Because they've not been used to combat human diseases before, it's hoped that they might be able to kill bacteria that had become drug-resistant.

One problem though is that many of these newly-identified chemicals are toxic⁴. So the next step will be to adapt them to make them benign⁵ to patients but lethal⁶ to bacteria.

The researchers point out that their work highlights the importance of preserving frog diversity. They say that many species whose skin might contain potentially valuable medicinal substances may become extinct soon because of a loss of habitat and water pollution.

Glossary⁷ 词汇表

to secrete⁸ something（指动物或植物器官)分泌 

germs 细菌 

antibiotics 抗生素 

to swab something （医学检验）涂片 

sample 采样 

species 物种 

to combat something 与…斗争 

drug-resistant 抗药的，耐药的 

toxic 有毒的 

benign 有益的，良性的 

bacteria （复数）细菌 

to highlight something 强调，突出 

to preserve something 保护 

diversity 多样性 

extinct 灭绝 

habitat 栖息处

Questions and Answers

How might frogs be useful to human medicine? 

Scientists think the chemicals that frogs use on their skin could be used to create new medicines.

What is the advantage of developing new antibiotics? 

They might be used against diseases that can overcome existing drugs.

Are these frog chemicals safe for humans? 

No, many of these chemicals are toxic and they need to be adapted to make them safe or benign.

True or false: The researchers say that it is important for there be a wide range of frog species. 

True, that is what is meant by "frog diversity".

1 secreting   

v.（尤指动物或植物器官）分泌( secrete的现在分词 )；隐匿，隐藏

参考例句：

• It is also an endocrine gland secreting at least two important hormones. 它也是一种内分泌腺，至少分泌二种重要的激素。 来自辞典例句
• And some calcite-secreting organisms also add magnesium to the mix. 有些分泌方解石的生物，会在分泌物中加入镁。 来自互联网

2 antibiotics   

n.（用作复数）抗生素；（用作单数）抗生物质的研究；抗生素，抗菌素( antibiotic的名词复数 )

参考例句：

• the discovery of antibiotics in the 20th century 20世纪抗生素的发现
• The doctor gave me a prescription for antibiotics. 医生给我开了抗生素。

3 secretions   

n.分泌（物）( secretion的名词复数 )

参考例句：

• Lysozyme is an enzyme found in egg white, tears, and other secretions. 溶菌酶是存在于卵白、泪和其他分泌物中的一种酶。 来自辞典例句
• Chest percussion and vibration are used with postural drainage to help dislodge secretions. 在做体位引流时要敲击和振动胸部帮助分泌物松动排出。 来自辞典例句

4 toxic   

adj.有毒的，因中毒引起的

参考例句：

• The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
• There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。

5 benign   

adj.善良的，慈祥的；良性的，无危险的

参考例句：

• The benign weather brought North America a bumper crop.温和的气候给北美带来大丰收。
• Martha is a benign old lady.玛莎是个仁慈的老妇人。

6 lethal   

adj.致死的；毁灭性的

参考例句：

• A hammer can be a lethal weapon.铁锤可以是致命的武器。
• She took a lethal amount of poison and died.她服了致命剂量的毒药死了。

7 glossary   

n.注释词表；术语汇编

参考例句：

• The text is supplemented by an adequate glossary.正文附有一个详细的词汇表。
• For convenience,we have also provided a glossary in an appendix.为了方便，我们在附录中也提供了术语表。

8 secrete   

vt.分泌；隐匿，使隐秘

参考例句：

• The pores of your body secrete sweat.身上的毛孔分泌汗液。
• Squirrels secrete a supply of nuts for winter.松鼠为准备过冬而藏坚果。