题目内容
Dieting, according to an old joke, may not actually make you live longer, but it sure feels that way. Nevertheless, evidence has been accumulating since the 1930s that calorie restriction-reducing an animal's energy intake below its energy consumption—extends lifespan and delays the appearance of age-related diseases in rats, dogs, fish and monkeys. Such results have inspired thousands of people to put up with constant hunger in the hope of living longer, healthier lives. They have also led to a search for drugs that imitate the effects of calorie restriction without the pain of going on an actual diet.
A study, known as CALERIE (Comprehensive Assessment of Long-term Effects of Reducing Intake of Energy), was sponsored by America's National Institutes of Health. It took 48 men and women aged between 25 and 50 and assigned them randomly to either a control group or a calorie-restriction regime. Those in the second group were required to cut their calorie intake for six months to 75% of that needed to maintain their weight.
The CALERIE study is a landmark in the history of the field, because its subjects were either of normal weight or only slightly overweight. Previous projects have used individuals who were clinically obese(肥胖的), thus confusing the unquestionable benefits to health of reducing obesity with the possible advantages of calorie restriction to the otherwise healthy.
At a molecular level, CALERIE suggests these advantages are real. For example, those on restricted diets had showed drops in body temperature and blood-insulin(胰岛素) levels—both phenomena that have been seen in long-lived, calorie-restricted animals. Dr Rattan doubts whether calorie restriction will extend maximum human life expectancy. He argues that the concepts of ageing and longevity(长寿) must be separated. It may, indeed, be possible to reduce or eliminate particular age-related diseases, and that would increase average lifespan in the way that eliminating other diseases has done in the past. But this is not the same as slowing down aging itself, and thus increasing maximum lifespan. Longevity is a more complex trait than any individual disease, and, in his opinion, it will not be altered so easily.
Cynthia Kenyon, a researcher looking into anti-aging drugs, believes that some molecules are likely to be approved in the next five to ten years, for guarding against age-related diseases. People then will start taking them, and a huge natural experiment will get under way. If Dr Rattan is wrong, maximum lifespan as well as average lifespan will increase. If he is right, at least people will enjoy a healthier old age.
It can be inferred from the first paragraph that ______.
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A．Bamboo was the food of the Shinto gods.B．The Shinto gods lived inside the bamboo.C．T
听力原文：W: Good evening and welcome to our program. Today we'll talk about several interesting cultural artifacts that are a part of daily lives of the Japanese, and perhaps other Asian countries as well. We're very happy to have Ben Smith here.
M: Thank you.
W: Well, artifacts made of bamboo are very important in Japanese culture.
M: Yes. For hundreds and even thousands of years, the bamboo plant has played an important role in the lives of the Japanese, and at one time, it was believed that the Shinto gods could be found in the stem of the bamboo plant, and this is something that is portrayed in one of Japan's oldest tales, The Tale of the Bamboo Cutter.
W: That sounds interesting. Bamboo is a very versatile plant. It's light and flexible, but strong, and there are many varieties of it. They can be used to make various artifacts.
M: Yeah, and some of them are really exquisite.
W: Very happily, Mr. Smith has brought here several bamboo artifacts. So can you introduce them to us, Mr. Smith？
M: Sure. The first one is a chashaku. It is a ten spoon, and it is used for measuring powdered green tea during the tea ceremony.
W: That's fine. What about this？
M: Uh, it is a tea whisk. It is for mixing the powdered green tea in a small bowl until it becomes a foamy mixture.
W: Wow, it is so nice and I love it. Thank you for showing us these fine artifacts, Mr. Smith.
M: My pleasure
(23)
听力原文： Purse snatching is an increasing common crime. There are estimated 50 to 100 purse snatchings each month in the New York City subways. One of the favored techniques is to stand between two subway cars and, as the train starts pulling out of the station, reach out and pull free a woman's purse.
Recently, a crime analysis officer for the New York Police Department found that purse stealing in Manhattan's top restaurants was up 5 percent over the previous year. When a woman puts her purse on a vacant chair at a table or at her feet beside her chair, she is inviting a purse snatcher to take it. Purse snatchers often work in pairs. When a target in a restaurant is sighted, one of them will create some kind of disturbance to gain the victim's attention. While the woman is looking away from her table, the actual snatcher will lift the purse. A popular technique is for the thief, man or woman, to carry an umbrella with the curved handle down. The umbrella handle suddenly hooks the bag and in an instant it is on the thief's wrist or under the coat over his arm if he is a man, and on its way out of the restaurant. Police advise that women in restaurants keep their purses either on their laps or on the floor between their legs.
Other purse snatchers who operate in theaters are called "seat tippers", victimizing women who put their purses down on an adjacent empty seat. Yet others specialize in snatching purses from ladies' rooms. When a woman is in a toilet stall, her purse should never be placed on the floor or hung on the coat hook on the door.
(33)
听力原文： "High tech" and "state of the art" are two expressions that describe very modern technology. High tech is just a shorter way of saying high technology. And high technology describes any invention, system or device that uses the newest ideas or discoveries of science and engineering.
What is high tech？ A computer is high tech. So is a communications satellite. A modern manufacturing system is surely high tech.
High tech became a popular expression in the United States during the early 1980's. Because of improvements in technology, people could buy many new kinds of products in American stores, such as home computers, microwave ovens, etc.
"State of the art" is something that is as modem as possible. It is a product that is based on the very latest methods and technology. Something that is "state of the art" means the newest possible design or product of a business or industry. A state of the art television set, for example, uses the most modern electronic design and parts. It is the best that one can buy.
"State of the art" is not a new expression. Engineers have used it for years, to describe the best and most modem way of doing something.
Millions of Americans began to use the expression in the late 1970's. The reason was the computer revolution. Every computer company claimed that its computers were "state of the art".
Computer technology changed so fast that a state of the art computer today might be old tomorrow. The expression "state of the art" became as common and popular as computers themselves. Now all kinds of products are said to be "state of the art".
(30)
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