Five cloned pigs,whose organs are much less likely to be rejected(排斥) by a patient,have been born in the U.S.

More than 62,000 people in the U.S. alone are waiting to ____ donated hearts,lungs and so on.The number of human donors falls far short of ____.Pig organs are of a(n) ____ size to human organs,and some scientists hope they might be used to help meet the ____.But previous attempts to transplant pig tissue into humans have ____.

The five pigs ____ a gene that adds a sugar to the surface of pig cells.The sugar would ____ immune(免疫的) rejection of the tissue.“This advance provides a near?time ____ for overcoming the problem that there is not enough human organs for transplants,”says an expert.“This is the ____ gene for overcoming the ____ stage of rejection.”

____,scientists warn that much more work is necessary ____ organs from copies of the pigs could be transplanted into humans.Human genes will need to be added,to ____ rejection of the organ in the long term.There are also ____ that pig viruses could infect patients.

Cloning techniques were ____ to the production of the pigs.Genes can only be knocked out(去除) in a single cell.Cloning of these single cells then allowed the ____ of a whole animal in which the gene was knocked out in every cell.But the PPL researchers have ____ in knocking out only one copy of the gene.The team will now attempt to knock out both copies of the gene.

The team will also ____ tests to investigate whether a virus from the pigs could infect human cells.“Although a lot of the work is very ____,we’re still very far off being able to grow an organ,” says Julia,who is working on this project and quite ____ to creating similar knock?out pigs with researchers at the University of Missouri.

1.A.exchange? B.check

C.possess? D.receive

2.A.discussion? B.demand

C.doubt? D.distance

3.A.beneficial? B.identical

C.similar? D.certain

4.A.shortage? B.condition

C.satisfaction? D.argument

5.A.continued? B.failed

C.finished? D.paused

6.A.lack? B.include

C.make? D.change

7.A.leave? B.cause

C.block? D.destroy

8.A.supply? B.ambition

C.contribution? D.solution

9.A.only B.rare

C.key? D.safe

10.A.last? B.whole

C.next? D.early

11.A.However? B.Therefore

C.Besides? D.Finally

12.A.because? B.before

C.if? D.after

13.A.prevent B.ignore

C.judge? D.weaken

14.A.regrets? B.emotions

C.concerns? D.interests

15.A.simple? B.vital

C.unusual? D.basic

16.A.collection? B.application

C.reception? D.creation

17.A.delighted? B.succeeded

C.joined? D.believed

18.A.conduct? B.plan

C.design? D.study

19.A.perfect? B.strange

C.exciting? D.disappointing

20.A.opposed? B.used

C.devoted? D.suited

 

His name is James,but people call him Rocky.The name fits.He’s big,over six feet tall,and he’s tough when he needs to? be.James “Rocky” Robinson lives and works in New York City’s Bedford?Stuyvesant district,one of the poorest and most dangerous neighborhoods in the United States.Yet it is here in Bed?Stuy that he is saving lives and reviving a community.

In 1966,when Rocky was twenty?six years old,his seven?year?old niece was struck by a car on the street of Bed?Stuy.Had someone at the scene known first aid or CPR,she might have lived.But by the time she reached a hospital,she was dead.

His niece’s unnecessary death was one reason why Rocky became a paramedic (护理人员).Working for the Emergency Medical Service of New York City,he realized that more than half the city’s emergency calls came from high?crime areas.According to Rocky,residents of crime?plagued minority neighborhoods like Bed?Stuy sometimes had to wait as long as 26 minutes after calling 911 for an ambulance while calls in richer white communities were answered in_a_fraction_of_the_time.

Rocky decided to find out more about the problem.His research showed that the richer communities had organized their own ambulance corps (特殊部队) to improve city services because the city was overwhelmed with calls.“If that’s the key to success,”he told his friend and EMT (Emergency Medical Technician) colleague,Joe Perez,“we’ll start our own corps in Bed?Stuy!”

In 1988,Rocky had no idea that he and Joe would be attempting to establish the first minority?run ambulance service in the country,or just how creative he would have to be to overcome the difficulty.The pair’s first challenge was to find a location for the headquarters.They took over an abandoned building that was commonly used by drug dealers.Because there was no electricity or running water (except for the leaks in the roof),the two men worked during daylight hours.They used a two?way radio to receive emergency calls.

Although they could make do with their new headquarters,Rocky and Joe still lacked the most important component of an ambulance service:an ambulance.An old Chevrolet (雪佛兰) got them to the scenes of accidents,fires,shootings,and stabbings.But the car didn’t always start.At times,they were forced to strap (用带捆绑) their trauma kits and oxygen tanks to their backs and run on foot to the emergencies.Everyone laughed,except the victims who were still alive when? Rocky and Joe arrived.

1.The author believes the name “Rocky” fits James because________.

A.he is a tall and tough man

B.he is tall and does something big

C.he is living in a tough community

D.he leads a tough community

2.James’ seven?year?old niece would have been saved if________.

A.she had been sent to a better hospital

B.she had got first aid and arrived in hospital earlier

C.James had been at the spot

D.emergency calls had been available in the area

3.The underlined phrase in Paragraph 3 means________.

A.in a short time

B.over a long time

C.in the near future

D.from time to time

4.We can infer from Paragraph 4 that________.

A.ambulance corps were only allowed in rich white communities

B.James found white communities made more emergency calls

C.city services were not enough to meet people’s need

D.it was easy to establish the minority?run ambulance service

 

Plastic is one of the most important technological discoveries of the 20th century.However,it may soon be replaced.The new development—liquid wood—can replace plastics in all branches of modern industries.

Plastic as a material enjoys the biggest demand in the modern world,but it does have a number of drawbacks.First and foremost,plastic isn’t recyclable.Secondly,it contains toxins (毒物) helping develop cancerous diseases.Finally,it’s made of oil and oil reserves aren’t endless.

The? liquid wood technology is likely to replace plastic and provide mankind with new materials for many years ahead.Norbert Eisenfreich,a senior researcher at? the Faunhofer Institute for Chemical Technology (ICT) in Germany,said that arboform,the new material,is made of lignin (木质素),which can be obtained from soft tissues of wood.Once mixed with several other materials,it turns into solid and non?toxic alternative for plastics.

ICT team leader Emilia Regina Inone?Kauffmann said the wood?working industry separates wood into three basic components,including lignin.Lignin isn’t used for the production of paper.Specialists of ICT mixed lignin with several natural materials and thus invented the material which could be melted and molded (铸型).

When solid,arboform looks like plastic and possesses the qualities of polished wood.It can be used for the production of any items.Arboform is already used for the production of car parts which require extra strength.In addition,liquid wood can be recycled repeatedly.The material preserved all of its qualities even if it’s reprocessed ten times.

However,the new invention doesn’t enjoy an extensive use due to the high content of sulphur (硫) in it.German researchers are sure to reduce the amount of sulphur by 90 percent very soon to make arboform usable for home needs.

1.According to the passage,plastic________.

A.plays a big role in the modern world

B.helps to protect our environment in some way

C.has been replaced by the newly discovered material

D.helps us to reduce the use of petrol

2.What’s the advantage of arboform over plastics?

A.It is easily made from natural oil.

B.It is more widely used in household.

C.It is recyclable and friendly to the environment.

D.It contains no poisonous materials.

3.It can be concluded that German researchers will focus their future work firstly on________.

A.the material’s extensive use

B.the content of sulphur in arboform

C.the production cost of arboform

D.the qualities of liquid wood

4.The main purpose of the passage is to________.

A.advertise the new material—arboform

B.introduce liquid wood which will replace plastic

C.advertise new products made of arboform

D.show readers how to produce arboform

 

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