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當(dāng)前位置： 2022-2023學(xué)年北京五十五中高二（下）月考英語(yǔ)試卷（3月份）> 試題詳情

A group of researchers led by Patrick Yu-Wai-Man.an ophthalmologist （眼科醫(yī)師） at Cambridge University，investigated a new genetic therapy for a form of blindness.Officially，their study was a failure.But it was also a great success，for 29 of the 37 participants reported big improvements in their vision.
   The disease in question is Leber Hereditary Optic Neuropathy （LHON）（遺傳性視神經(jīng)病變） .A defective gene leads to sudden and rapid loss of sight，with many sufferers becoming legally blind within a year.It affects between one in 30，000 and one in 50，000 people.Men in their 20s and 30s are particularly at high risk.Since most cases are caused by a mutation （突變） in a single gene，LHON is a good candidate for gene therapy，a form of genetic engineering which aims to replace the defective gene with a working one.
   With that in mind.Dr Yu-Wai-Man and his colleagues loaded up a changed virus with a corrected copy of the gene and injected it into their patients' eyes.The researchers controlled the experiment by injecting only one of each patient's eyes--chosen at random--with the virus.The other eye was given a fake injection.Using two eyes in the same patient makes for a perfect control.
   The surprise came several months later.The researchers had hoped to see a big improvement in the treated eyes，compared with the untreated ones.They did not，for which the study failed in its primary objective.Instead，in more than three quarters of their patients，they saw significant improvements in both eyes.
   On the face of it，that was odd.Only one eye had received the treatment，after all.Follow-up studies in monkeys confirmed what the researchers had suspected.The virus，it seemed，had found a way to travel from one eye to the other，probably via the optic nerve.Tissues and fluids samples from monkeys given the same treatment as the human patients showed viral DNA in both eyes，not just one.
   Although it had a happy outcome in this case，the prospect of a gene-therapy virus travelling to places it is not intended to go to might worry regulators.Fortunately，the researchers found no trace of the virus elsewhere in the monkeys' bodies.And.though the study was technically a failure，its practical success means that an effective treatment for LHON may at last be in reach.

（1）LHON is chosen in this study because it

A．can be easily cured
B．a(chǎn)ffects young males mostly
C．is a common disease among people
D．results from a mutation in a single gene
（2）Why was the study a great success despite a failure officially？

A．Some participants suffered loss of sight
B．The vision of both eyes improved greatly
C．All the participants gave positive feedback
D．The virus didn't replace the damaged gene
（3）The experiment on monkeys is mentioned in order to

A．confirm the virus travels across eyes
B．prove the virus can affect other body parts
C．show the effect of the treatment on animals
D．highlight regulators' worry about gene-therapy
（4）Which is the best title for the passage？

A．The Future of Gene Therapy
B．The Blessing for Eye Patients
C．Gene Therapy：Eyeball to Eyeball
D．Virus Treatment：From Humans to Monkeys

【考點(diǎn)】健康；說(shuō)明文．

【答案】D；B；A；C

【解答】

【點(diǎn)評(píng)】

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發(fā)布：2024/7/11 8:0:9組卷：1引用：1難度：0.5

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發(fā)布：2024/9/6 7:0:8組卷：12引用：1難度：0.5
解析
2．    Soda and sports drinks are the largest single source of added sugars for Americans.They add an average of 145 calories a day to our diets.Most efforts to reduce drinking focus on soda.That is not enough.Juice is as bad.
    Americans drink a lot of juice.The average adult drinks 6.6 gallons per year.More than half of preschool-age children drink juice every day.These children drink about 10 ounces every day.That is more than twice the amount that is good for them.Fruit juice contains some nutrients（營(yíng)養(yǎng)物）.But it has tons of sugar.One 12-ounce glass of orange juice contains ten teaspoons of sugar.That is about what is in a can of Coke.
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    Government food programs for kids are also at fault.Children in these programs drink more fruit juice than they should.
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（1）What do most efforts to decrease drinking center on？

A．Coffee.
B．Juice.
C．Soda.
D．Tea.
（2）What can we say about fruit juice according to the text？

A．It is equal to fruit.
B．It contains much sugar.
C．It contains no nutrients.
D．It does no harm to health.
（3）Which of the following may the author agree with？

A．Drinking fruit juice can't replace the whole fruit.
B．Drinking fruit juice reduce the risk of diabetes.
C．100 percent juice can serve half day's nutrients.
D．Fortified orange juice can provide enough calcium.
（4）In which section may the text appear in a newspaper？

A．Travel.
B．Technology.
C．Environment.
D．Health.
發(fā)布：2024/8/6 8:0:9組卷：2引用：1難度：0.3
解析
3．    Many college students turn to ADHD（注意缺陷障礙）medicine during the exam week，which is regarded as "smart drugs" that will help their academic（學(xué)術(shù)的）performance.The thinking is that if the drugs help students with ADHD improve their focus，they should provide the same benefit for people who don't have the disorder.
    But a new study shows that drugs can actually damage brain function of healthy students who take the drug hoping to boost their intelligence. "It's not a smart drug which will suddenly improve their ability to understand information they read，" said Lisa Weyandt，a professor at the University of Rhode Island.
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    Worse，the ADHD drug actually harms students' memory.It's often misused because people pull all-nighters and they're tired，and they think it's going to keep them awake.Maybe it does，but it's certainly not going to help their academic work.The brain is still developing until the mid to late 20s.It's important to keep it healthy.There's also a chance that ADHD drugs could endanger a student's heart health.

（1）Why do some college students take ADHD drugs？

A．To improve their sleeping.
B．To get higher marks.
C．To make them feel relaxed.
D．To treat brain disorder.
（2）Which of the following is closest in meaning to the word "boost" in Paragraph2？

A．Analyze.
B．Affect.
C．Improve.
D．Understand.
（3）What effect did ADHD drugs have on the students？

A．They became more focused.
B．Their blood pressure was reduced.
C．Their reading fluency was greatly raised.
D．They could remember better and more quickly.
（4）What is the author's attitude towards the ADHD drug？

A．Indifferent.
B．Positive.
C．Doubtful.
D．Negative.
發(fā)布：2024/8/7 8:0:9組卷：1引用：1難度：0.5
解析

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