题目内容
Simply by analyzing a drop of blood, a doctor will be able to diagnose a birth defect or even cancer when it is in the early stage; using new technology, a material lighter but much stronger than steel can be produced.
These may sound like dreams at present. But the dreams may soon come true as research findings in laboratories are being turned into products more rapidly in the new century, according to experts participating in the fourth Asia-Pacific Economic Cooperation (APEC) Technomart, a technology exhibition and trade fair in Suzhou.
"Most people think nano-technology(纳米技术)is too far-fetched to be real. But in fact nano-technology has been applied in a wide range of fields, such as medicine. It is coming into our daily life," said Cheng Jiachong from a Hong Kong-based nano-technology firm.
Nano-technology based on the nanometer, the unit of which is a billionth of a meter, enables scientists to have new concepts of disease diagnosis and treatment on a molecular(分子)and atomic scale, Cheng said.
By using nanometer particles, a doctor can separate the fetus cells(胚胎细胞)from the blood of a pregnant woman to see if the development of the fetus is normal. This method is also being used in the early diagnosis of cancer and heart disease, he said.
One of the most significant impacts of nano-technology is at the bio-inorganic materials interface, according to Greg Tegart, executive advisor of the APEC Center for Technology Foresight.
"By combining enzymes(酶)and silicon chips we can produce biosensors. These could be implanted in humans or animals to monitor health and to deliver corrective doses(剂量)of drugs," he told the participants a technology forum during the exhibition.
"Nano-technology could affect the production of nearly every man-made object, from automobiles, tires and computer circuits(电路), to advanced medicines and tissue replacement, and lead to the invention of objects yet to be imagined," said David Minns, a special advisor to the National Research Council of Canada.
It has been shown that carbon nano-tubes are ten times as strong as steel, with one sixth of the weight, and nano-scale systems have the potential to make supersonic transport cost- effective and to increase computer efficiency by millions of times, he said.
The experts agreed that the APEC technology exhibition and trade fair provided many chances for exchanges of innovative ideas and products.
【小题1】Realization of the dreams mentioned in the first paragraph will mainly base on ________.
A.APEC | B.Chinese scientist |
C.the APEC Center for Technology Foresight | D.Nano-technology |
A.meter | B.meter | C.meter | D.meter |
A.Nano-technology could only be used to invent new objects. |
B.Nano-technology could be widely used to produce or invent objects. |
C.Nano-technology is a money-consuming technology. |
D.Nano-technology can not be used to improve the service of Internet. |
A.stronger and lighter | B.lighter but as strong |
C.stronger but as light | D.poor in quality |
【小题1】D
【小题1】A
【小题1】B
【小题1】A
解析
Like distance runners on a measured course,all of us will move through time in a roughly predictable pattern.
In the first stage of our lives,we develop and grow, reaching toward the top of physical vitality(活力).
After we grow up,however, the body begins a process of gradually wearing out.
A new awareness of physical fitness may help lengthen our years of health and vitality,yet nothing we do will work to stop the unavoidable force of aging.
Most of the changes of aging take place deep inside the body.The lungs become less able to take in oxygen.Powerful muscles gradually lose their strength.The heart loses power and pumps less blood.Bones grow easier to break.
Finally, we meet a stress,a stress that is greater than our physical resistance.Often,it is only a minor accident or chance infection(a disease caused by virus),but this time,it brings life to an end.
In 1932,a classic experiment nearly doubled the lifetime of rats,simply by cutting back the calories in their diet The reason for the effect was then unknown.
Today, at the University of California at Berkley, Dr.Paul Seagle has also greatly lengthened the normal lifetime of rats.The result was achieved through a special protein limited diet,which had a great effect on the chemistry of the brain.Seagle showed that within the brain,specific chemicals control many of the signals that influence aging.By changing that chemical balance,the clock of aging can be reset.
For the first time, the mystery of why we age is being seriously challenged.Scientists in many fields are now making striking and far-reaching discoveries.
An average lifetime lasts 75 years,yet in each of us lies a potential for a longer life.If we could keep the vitality and resistance to disease that we have at age twenty, we would live for 800 years.
1.What does the underlined word “it” refer to?
A.Physical vitality. |
B.Stress. |
C.Aging. |
D.Physical resistance. |
2.Which of the following is not a change of aging?
A.People gradually lose their muscle strength. |
B.Bones tend to break more easily. |
C.The heart loses power and pumps less blood. |
D.The lungs become unable to take in oxygen. |
3.The author believes the following except that .
A.human's life pattern is predictable |
B.physical fitness can't stop the force of aging |
C.human's lifetime will last longer than 75 years |
D.all of the changes of aging take place deep inside the body |
4.How did Dr.Paul Seagle lengthen the lifetime of rats in his experiment?
A.By keeping their physical fitness. |
B.By cutting the calories in their diet. |
C.By resetting their clock of aging. |
D.By limiting the protein in their diet. |
5.What is probably the best title for the article?
A.Two Great Experiments |
B.The Mystery of Human Life |
C.The Breakthrough in the Study of Aging |
D.Ways to lengthen Human Life |
Most British telephone cards are just plain green, but card collecting is becoming a popular hobby in Britain and collectors even have their own magazine, International Telephone Cards. One reason for their interest is that cards from around the world come in a wide variety of different and often very attractive designs. There are 100, 000 different cards in Japan alone, and there you can put your own design onto a blank card simply by using a photograph or a business card.
The first telephone cards, produced in 1976, were Italian. Five years later the first British card appeared, and now you can buy cards in more than a hundred countries. People usually start collecting cards because they are attractive, small and light , and they do not need much space. It is also a cheap hobby for beginners, although for some people it becomes a serious business. In Paris, for example, there is a market where you can buy only telephone cards, and some French cards cost up to 4, 000 pounds. The first Japanese card has a value of about 28, 000 pounds. Most people only see cards with prices like these in their collectors magazine.
1.The text is mainly about ________ .
A.the history of phone cards |
B.phone card collecting as a hobby |
C.reason for phone card collecting |
D.the great variety of phone cards |
2.When did people in Britain begin to use phone cards?
A.In 1971. |
B.In 1975. |
C.In 1976. |
D.In 1981. |
3.The main reason for most people to collect phone cards is that ________ .
A.they find the cards beautiful and easy to keep |
B.they like to have something from different countries |
C.they want to make money with cards |
D.they think the cards are convenient to use |
4.The writer mentions a market in Paris in order to show that ________
A.card collecting is popular among young people |
B.French and Japanese cards are the most valuable |
C.people can make money out of card collecting |
D.card collectors magazines are very useful |