早教吧作业答案频道 -->英语-->
阅读理解。Medicaldrugssometimescausemoredamagethantheycure.Onesolutiontothisproblemistoputthedrugsinsideacapsuleprotectingthemfromthebody-andthebodyfromthem-untiltheycanbereleasedatjusttheright
题目详情
阅读理解。
Medical drugs sometimes cause more damage than they cure. One solution to this problem is to
put the drugs inside a capsule protecting them from the body-and the body from them-until they
can be released at just the right spot. There are lots of ways to trigger (引发) this release including
changing temperature acidity and so on. But triggers can come with their own risks-burns for example.
Now researchers in California have designed what could be a harmless trigger to date: shining near-infrared light (NIR 近红外线) on the drug in the capsule.
The idea of using light to liberate the drug in the capsule isn't new. Researchers around the globe have
developed polymers (聚合物) and other materials that begin to break down when they
absorb either ultraviolet (UV 紫外线) or visible light. But tissues also readily absorb UV and
visible light which means the drug release can be triggered only near the skin where the light can
reach the capsule. NIR light largely passes through tissues so researchers have tried to use it as a
trigger. But few compounds (化合物) absorb NIR well and go through chemical changes.
That changed last year when Adah Almutairi a chemist at the University of California San
Diego reported that she and her colleagues had designed a polymer that breaks down when it
absorbs NIR light. Their polymer used a commercially available NIR-absorbing group called
o-nitrobenzyl (ONB). When they catch the light ONB groups fall off the polymer leading to its
breakdown. But ONB is only a so-so NIR absorber and it could be poisonous to cells when it
separates from the polymer.
So Almutairi and her colleagues reported creating a new material for capsules that's even better.This
one consists of a long chain of compounds called cresol groups linked in a polymer. Cresol contains
reactive(易反应的) components that make it highly unstable in its polymeric form a feature Almutairi
and her colleagues use to their advantage. After polymerizing the cresols they cap each reactive
component with a light-absorbing compound called Bhc. When the Bhcs absorb NIR light the reactive
groups are exposed and break the long polymer into two short chains. Shining additional light continues
this breakdown potentially releasing any drugs in the capsule. What's more Almutairi says Bhc is 10
times better at absorbing NIR than is ONB and is not poisonous to cells.
put the drugs inside a capsule protecting them from the body-and the body from them-until they
can be released at just the right spot. There are lots of ways to trigger (引发) this release including
changing temperature acidity and so on. But triggers can come with their own risks-burns for example.
Now researchers in California have designed what could be a harmless trigger to date: shining near-infrared light (NIR 近红外线) on the drug in the capsule.
The idea of using light to liberate the drug in the capsule isn't new. Researchers around the globe have
developed polymers (聚合物) and other materials that begin to break down when they
absorb either ultraviolet (UV 紫外线) or visible light. But tissues also readily absorb UV and
visible light which means the drug release can be triggered only near the skin where the light can
reach the capsule. NIR light largely passes through tissues so researchers have tried to use it as a
trigger. But few compounds (化合物) absorb NIR well and go through chemical changes.
That changed last year when Adah Almutairi a chemist at the University of California San
Diego reported that she and her colleagues had designed a polymer that breaks down when it
absorbs NIR light. Their polymer used a commercially available NIR-absorbing group called
o-nitrobenzyl (ONB). When they catch the light ONB groups fall off the polymer leading to its
breakdown. But ONB is only a so-so NIR absorber and it could be poisonous to cells when it
separates from the polymer.
So Almutairi and her colleagues reported creating a new material for capsules that's even better.This
one consists of a long chain of compounds called cresol groups linked in a polymer. Cresol contains
reactive(易反应的) components that make it highly unstable in its polymeric form a feature Almutairi
and her colleagues use to their advantage. After polymerizing the cresols they cap each reactive
component with a light-absorbing compound called Bhc. When the Bhcs absorb NIR light the reactive
groups are exposed and break the long polymer into two short chains. Shining additional light continues
this breakdown potentially releasing any drugs in the capsule. What's more Almutairi says Bhc is 10
times better at absorbing NIR than is ONB and is not poisonous to cells.
1. According to the passage which of the following could be the best trigger?
A. Temperature change.
B. NIR light.
C. Acidity change.
D. UV light.
B. NIR light.
C. Acidity change.
D. UV light.
2. Why is ONB unsatisfactory?
A. It breaks down when it absorbs NIR light.
B. It falls off the polymer and triggers drug release.
C. It has not come onto the market up till now.
D. It is not effective enough and could be poisonous.
B. It falls off the polymer and triggers drug release.
C. It has not come onto the market up till now.
D. It is not effective enough and could be poisonous.
3. Which word can be used to complete the following process of changes?
A. protected
B. formed
C. exposed
D. combined
B. formed
C. exposed
D. combined
▼优质解答
答案和解析
1-3: BDC
看了 阅读理解。Medicaldr...的网友还看了以下:
《树上的天使》阅读解答题, 2020-04-07 …
阅读《青年文摘》《满分阅读》之类的书对提高现代文阅读解题能力有帮助吗?阅读时脑子要思考什么? 2020-04-27 …
求阅读解答,急的!阅读《生命的消失》(作者:邢庆杰)1小说先写沙漠遇狼,再写参团探险的原因和遇风暴 2020-06-08 …
怎样做才能把英语的阅读理解和完型填空全都做对?有什么做阅理解和完形填空的方法么? 2020-06-13 …
阅读解答题:有些大数值问题可以通过用字母代替数转化成整式问题来解决,请先阅读下面的解题过程,再解答 2020-07-01 …
阅读解答(阅读是鄂教版五年级语文书里)四单元1、盘古()地站在那里,把天和地分开,又不知道经过了多 2020-07-06 …
解读个园阅读解读个园个园之名甚“个”.据扬州人讲,当年园主人为求园名,花了不少银子,才有了个园这名 2020-07-08 …
我考英语二,阅读要怎么复习我考的是英语二,现在在纠结,要不要认真研究英语一,有人说,英语一的阅读解 2020-07-26 …
阅读解答题对于形如x2+2ax+a2这样的二次三项式,可以用公式法将它分解成(x+a)2的形式.但 2020-07-31 …
解读个园阅读解读个园个园之名甚“个”。据扬州人讲,当年园主人为求园名,花了不少银子,才有了个园这名字 2020-12-08 …