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        1. 閱讀理解

            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(引發(fā))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,近紅外線)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 cither ultraviolet(UV,紫外線)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(易反應(yīng)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.

          (2)

          Why in 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.

          (3)

          Which word can be used to complete the following process of changes?

          [  ]

          A.

          Protected

          B.

          formed

          C.

          exposed

          D.

          combined

          答案:1.B;2.D;3.C;
          解析:

          (1)

          細節(jié)理解題.根據(jù)第一段“Now, researchers in California have designed what could be a harmless trigger to date:shining near-infrared light on the drug in the capsule.”可知,應(yīng)選B項.

          (2)

          推理判斷題.根據(jù)第三段中“…ONB groups fall off the polymer, leading to its breakdown”和“…and it could be poisonous to cells…”可知,應(yīng)選D項.

          (3)

            試題解析:細節(jié)理解題.根據(jù)最后一段中“When the Bhcs absorb NIR light, the reactive groups are exposed…”可知此處用exposed,即C項正確.

            長難句解析:

            1.Researchers around the globe have developed polymers(聚合物)and other materials that begin to break down when they absorb cither ultraviolet(UV,紫外線)or visible light.

            本句是polymers(聚合物)and other materials的定語從句,when 引導(dǎo)的時間狀語從句.

            2.This one consists of a long chain of compounds called cresol groups linked in a polymer.Cresol contains reactive(易反應(yīng)的)components that make it highly unstable in its polymeric form, a feature

            本句是called動詞過去分詞做后置定語,修飾a long chain of compounds.后面是reactive(易反應(yīng)的)components的定語從句

            考點:日常生活類-說明文

            文章大意:本文圍繞“怎樣使用膠囊,讓我們生病吃藥更加安全、而且療效好”這個主題展開研究,來展開話題的.


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          科目:高中英語 來源:2010年普通高等學(xué)校招生全國統(tǒng)一考試、英語(湖南卷) 題型:050

          閱讀理解

            When Mary Moore began her high school in 1951, her mother told her,"Be sure and take a typing course so when this show business thing doesn't work out, you'll have something to rely on."Mary responded in typical teenage fashion.From that moment on, "the very last thing I ever thought about doing was taking a typing course,"she recalls.

            The show business thing worked out, of course.In her career, Mary won many awards.Only recently, when she began to write Growing Up Again, did she regret ignoring her morn," I don't know how to use a computer," she admits.

            Unlike her 1995 autobiography, After All, her second book is less about life as an

          award-winning actress and more about living with diabetes(糖尿病).All the money from the book is intended for the Juvenile Diabetes Research Foundation(JDRF), an organization she serves as international chairman."I felt there was a need for a book like this," she says."I didn't want to lecture, but I wanted other diabetics to know that things get better when we're self-controlled and do our part in managing the disease."

            But she hasn't always practiced what she teaches.In her book, she describes that awful day, almost 40 years ago, when she received two pieces of life-changing news.First, she had lost the baby she was carrying, and second, tests showed that she had diabetes.In a childlike act, she left the hospital and treated herself to a box of doughnuts(甜甜圈).Years would pass before she realized she had to grow up-again-and take control of her diabetes, not let it control her.Only then did she kick her three-pack-a-day cigarette habit, overcome her addiction to alcohol, and begin to follow a balanced diet.

            Although her disease has affected her eyesight and forced her to the sidelines of the dance floor, she refuses to fall into self-pity."Everybody on earth can ask, 'why me?' about something or other," she insists."It doesn't do any good.No one is immune(免疫的)to heartache, pain, and disappointments.Sometimes we can make things better by helping others.I've come to realize the importance of that as I've grown up this second time.I want to speak out and be as helpful as I can be."

          (1)

          Why did Mary feel regretful?

          [  ]

          A.

          She didn't achieve her ambition.

          B.

          She didn't take care of her mother.

          C.

          She didn't complete her high school.

          D.

          She didn't follow her mother's advice.

          (2)

          We can know that before 1995 Mary ________

          [  ]

          A.

          had two books published

          B.

          received many career awards

          C.

          knew how to use a computer

          D.

          supported the JDRF by writing

          (3)

          Mary's second book Growing Up Again is mainly about her ________

          [  ]

          A.

          living with diabetes

          B.

          successful show business

          C.

          service for an organization

          D.

          remembrance of her mother

          (4)

          When Mary received the life-changing news, she ________.

          [  ]

          A.

          lost control of herself

          B.

          began a balanced diet

          C.

          Med to get a treatment

          D.

          behaved in an adult way

          (5)

          What can we know from the last paragraph?

          [  ]

          A.

          Mary feels pity for herself.

          B.

          Mary has recovered from her disease.

          C.

          Mary wants to help others as much as possible.

          D.

          Mary determines to go back to the dance floor.

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