Rats that eat high levels of a natural sugar known as fructose（果糖） seem to age faster than other rats--and the same could be true for people who eat too much sweet junk food, Israeli researchers said Monday.
　　Fructose, found naturally in honey and fruit, is used widely in foods ranging from soft drinks to yogurt（酸奶）. But while its sweet taste is popular, the sugar could cause wrinkles and health problems, the researchers said. Dr. Moshe Werman and Boaz Levi of the Technion-Israel Institute of Technology fed large amounts of fructose to laboratory rats. Writing in the Journal of Nutrition, they said the fructose-fed rats showed changes in the collagen（膠原蛋白）of their skin and bones.
　　Collagen, a fibrous protein found in connective tissue, bone and cartilage, basically holds the body together. The loss of collagen is what causes loose skin and deep wrinkles in older people.
　　The process affected, Werman's team said, is known as "cross linking". "Too much cross-linking reduces flexibility(彈性) and makes the skin stiff and rigid, and these are the conditions that encourage wrinkled skin," Werman said in a statement. He said the same could be true of people, although this has not been shown. "Americans are eating more and more processed foods, such as carbonated drinks, baked goods, canned fruits, jams and dairy products that contain fructose，than Asian people," Werman said. Other studies have shown that high fructose intake can affect how the body handles glucose and increases insulin resistance——which can both be important measures of the tendency toward diabetes(糖尿病).　　

The rats Werman worked with were fed much more than the average adult person might eat in a day, which is standard in such experiments. The rats were fed 12.5 grams of fructose per kg (2.2 pounds) of weight every day for a year. To compare, a person weighing 154 pounds (70kg) who drinks a quart (liter) of cola consumes about 60 grams of fructose, or 0.8 grams per kg of body weight.

60.If people eat too much fructose, they may have the following signs EXCEPT________.

A. loose skin     B. deep wrinkles     C. a sweet tooth      D. aging faster

61.According to the passage, diabetes is diagnosed (診斷) mainly by measuring________.

  A. the amount of fructose eaten         B. the loss of collagen

  C. the cross linking                  D. glucose and insulin resistance

62. What can we infer from the passage? ________

A. Americans are easier to have diabetes than Asians.

  B. Diabetes can only be controlled, not cured.

  C. People eating too much fructose must have health problems.

  D. It’s abnormal to feed more fructose to the rats than an adult in the experiment.

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科目：高中英語 來源： 題型：閱讀理解

A chemical important of brain development may play a role in explaining why some people are genetically (由基因決定地) likely to suffer from anxiety and could lead to new treatments, U．S. researchers said.

They said highly anxious rats which were kept had very low levels of a brain chemical called fibroblast growth factor 2 or FGF2, compared with rats that were more relaxed. But when they improved the anxious rats' living conditions—giving them new toys to explore and a bigger cage to live in—levels of this brain chemical increased and they became less anxious.

“The levels of this brain chemical increased in response to the experiences that the rats were exposed to. It also decreased their anxiety.”Javier Perez of the University o f Michigan said in a telephone interview. “It made them behave the same way as the rats that were relaxed，”he said.

In a former study of people who were severely depressed before they died, the team found the gene that makes FGF2 was producing very low levels of the growth factor, which is known primarily for organizing the brain during development and repairing it after injury.

Perez thinks the brain chemical may be a marker for genetic vulnerability (脆弱性) to anxiety and depression. But it can also respond to changes in the environment in a positive way, possibly by preserving new brain cells.

While both the calm and anxious rats produced the same number of new brain cells, these cells were less likely to survive in the high－anxiety rats, the team found. Giving the rats better living conditions or injecting them with FGF2 helped improve cell survival.

“This discovery may pave the way for new, more specific treatments for anxiety that will not be based on sedation(藥物鎮(zhèn)靜), but will instead fight the real cause of the disease，” Dr. Pier Vincenzo Piazza from France said in a statement.

6. We know from the passage that with the levels of FGF2 decreasing, the rats will ________.

A. die of anxiety soon          B. suffer from a headache

C. become more relaxed        D. become more anxious

7. What's the better way to increase the levels of FGF2?

A. Introducing more companions to the anxious rats.

B. Improving the living conditions of the anxious rats.

C. Injecting the anxious rats with some special medicine.

D. Giving the anxious rats more time to relax.

8. The underlined word “it” in Paragraph 4 refers to ________.

A. the team                 B. the gene

C. the growth factor          D. the brain

9. What's the main influence of the new discovery?

A. Doctors won't use any medicine to cure anxiety.

B. Doctors may treat anxiety more efficiently.

C. Doctors will find the real cause of anxiety.

D. Doctors may find new medicine for anxiety.

10. Which of the following would be the most suitable title for the passage?

A. Anxious rats and relaxed rats

B. Anxiety—a serious mental disease

C. Scientific research into the brain is important

D. Brain chemical may play key role in anxiety

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科目：高中英語 來源：2013-2014學(xué)年浙江省高三上學(xué)期期末考試英語試卷（解析版） 題型：閱讀理解

American researchers found females are the more talkative sex because of a special “l(fā)anguage protein(蛋白質(zhì))” in the brain.

??? The study, conducted by neuroscientists (神經(jīng)學(xué)家)and psychologist from the University of Maryland, concluded that women talked more because they had more of the Foxp2 protein. The research, published in the Journal of Neuroscience, found that higher levels were found among humans that were women but in rats that were males. Their findings came after it was previously claimed that ladies speak about 20,000 words a day – over 13,000 more than men. “This study is one of the first to report a sex difference in the expression of a language-associated protein in humans or animals,” said Prof Margaret McCarthy, who led the study. In their study, the researchers attempted to determine what might make male rats more vocal than their female friends.

They separated four-day-old rats from their mothers and then counted the number of times they cried out in the “ultrasonic range”, the frequencies higher than humans can hear, over five minutes. While both sexes called out hundreds of cries, the males called out twice as often, they found. But when the pups were returned to their mother’s cage, she fussed over her sons first. Tests conducted on the parts of the brain known to be associated with vocalcalls showed the male pups have up to twice as much Foxp2 protein as the females. The researchers then increased the production in the brains of female pups and reduced it in males. This led to the female rats crying out more often and their mothers showing more interest to them. In contrast, males became less “talkative”.

??? The researchers then tested samples from ten children, aged between three and five, which showed that females had up to 30 per cent more of the Foxp2 protein than males, in a brain area key to language in humans.

??? “Based on our observations, we assume higher levels of Foxp2 in girls and higher levels of Foxp2 in male rats is an indication that Foxp2 protein levels are associated with the more communicative sex,” said Prof McCarthy. “Our results imply Foxp2 as a component of the neurobiological basis of sex differences in vocal communication in mammals. “

1.From the second paragraph, we can learn that ________.

A. women always speak more words than men

B. men and male rats have low levels of language protein

C. women and male rats have similar levels of Foxp2

D. McCarthy isn’t the first to find females more talkative

2.The underlined phrase “fussed over” in the third paragraph probably means______.

A. paid attention to????????????? ????????????? B. related to????????????? ????????????? C. put pressure on????????????? ????????????? D. counted on

3.The researchers carried out the experiments on rats in order to _______.

A. test which part of the brain is key to language in rats and humans

B. prove the levels of Foxp2 protein in humans and rats are different

C. determine the reason why female rats are more talkative than male rats

D. discover the association between Foxp2 protein and vocal communication

4.Which of the following can be the best title for the passage ?

A. Tests on humans and rats ????????????? ??? ????????????? ?????????????

B. Why women are the talkative sex

C. Sex differences in Foxp2 protein????????????? ????????????? ?????????????

D. Foxp2 protein determines oral ability

 

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科目：高中英語 來源：2016屆上海市高一上學(xué)期第一次月考英語試卷（解析版） 題型：閱讀理解

The scientists observed that the more junk food the rats ate, the more they wanted to eat – a behavior very similar to that of rats addicted(上了癮的) to heroin, a dangerous drug. Johnson said the experiment shows that the brain chemistry of obesity(肥胖) and drug addiction may be quite similar.

In their experiment, Johnson and his team studied the “pleasure center” of rats’ brains. The pleasure center is a complicated network of nerve cells. If the animal exercises or eats, the cells reward the animal by releasing chemicals into the body that make it feel good. And when the body feels good, the animal – or person – will want to do the behavior again.

For the experiment, Johnson fed foods like cheesecake to one group of rats. Food like this is high in calories and fat. Another group of rats got a regular diet. The rats that ate junk food started to eat more and more.

“They’re taking in twice the amount of calories as the control rats,” says Paul Kenny, one of Johnson’s colleagues.

Kenny and Johnson wanted to know what was going on in the brains of these rats. They first designed a way to deliver a small electrical charge to the rats’ brains. This electrical charge would stimulate the pleasure centers to release pleasure-causing chemicals. The rats could control how much stimulation – and how much pleasure – they received by running on a wheel. The more the rat ran, the more pleasure it received.

The rats that had been eating junk food started running more and more. This behavior suggested that the junk-food-eating rats needed more brain stimulation to feel good compared with rats on a normal diet. In other words, their pleasure centers were becoming less sensitive and the junk food didn’t make them feel good unless they ate more and more.

Experiments like this one could help scientists understand how chemicals in the brain contribute to obesity. With that information, they may be able to help people avoid obesity in the first place.

 

(Note: Answer the questions or complete the statements in NO MORE THAN TEN WORDS.)

 

1. The scientists suggested it was actually ___________________ that made the rats feel good.

2. How did the scientist know what was happening in the brains of the junk-food-eating rats?

3.What was the purpose of the experiment mentioned in the article?

 

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科目：高中英語 來源：2013-2014學(xué)年浙江省高三上學(xué)期期中考試英語試卷（解析版） 題型：閱讀理解

American researchers found females are the more talkative sex because of a special “l(fā)anguage protein(蛋白質(zhì))” in the brain.

    The study, conducted by neuroscientists （神經(jīng)學(xué)家）and psychologist from the University of Maryland, concluded that women talked more because they had more of the Foxp2 protein. The research, published in the Journal of Neuroscience, found that higher levels were found among humans that were women but in rats that were males. Their findings came after it was previously claimed that ladies speak about 20,000 words a day – over 13,000 more than men. “This study is one of the first to report a sex difference in the expression of a language-associated protein in humans or animals,” said Prof Margaret McCarthy, who led the study. In their study, the researchers attempted to determine what might make male rats more vocal than their female friends. 

They separated four-day-old rats from their mothers and then counted the number of times they cried out in the “ultrasonic range”, the frequencies higher than humans can hear, over five minutes. While both sexes called out hundreds of cries, the males called out twice as often, they found. But when the pups were returned to their mother’s cage, she fussed over her sons first. Tests conducted on the parts of the brain known to be associated with vocalcalls showed the male pups have up to twice as much Foxp2 protein as the females. The researchers then increased the production in the brains of female pups and reduced it in males. This led to the female rats crying out more often and their mothers showing more interest to them. In contrast, males became less “talkative”.

The researchers then tested samples from ten children, aged between three and five, which showed that females had up to 30 per cent more of the Foxp2 protein than males, in a brain area key to language in humans.

“Based on our observations, we assume higher levels of Foxp2 in girls and higher levels of Foxp2 in male rats is an indication that Foxp2 protein levels are associated with the more communicative sex,” said Prof McCarthy.

“Our results imply Foxp2 as a component of the neurobiological basis of sex differences in vocal communication in mammals. ”

1.From the second paragraph, we can learn that ________.

A．women always speak more words than men

B．men and male rats have low levels of language protein

C．women and male rats have similar levels of Foxp2

D．McCarthy isn’t the first to find females more talkative

2.The underlined phrase “fussed over” in the third paragraph probably means______.

A．paid attention to B．related to    C．put pressure on  D．counted on

3.The researchers carried out the experiments on rats in order to _______.

A．test which part of the brain is key to language in rats and humans

B．prove the levels of Foxp2 protein in humans and rats are different

C．determine the reason why female rats are more talkative than male rats

D．discover the association between Foxp2protein and vocal communication

4.Which of the following can be the best title for the passage ?

A．Tests on humans and rats

B．Why women are the talkative sex

C．Sex differences in Foxp2 protein

D．Foxp2 protein determines oral ability

 

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科目：高中英語 來源：2012-2013學(xué)年江蘇省鹽城市高三第二次模擬（3月）考試英語試卷（解析版） 題型：閱讀理解

American researchers found females are the more talkative sex because of a special “l(fā)anguage protein(蛋白質(zhì))” in the brain.

The study, conducted by neuroscientists （神經(jīng)學(xué)家）and psychologist from the University of Maryland, concluded that women talked more because they had more of the Foxp2 protein. The research, published in the Journal of Neuroscience, found that higher levels were found among humans that were women but in rats that were males. Their findings came after it was previously claimed that ladies speak about 20,000 words a day – over 13,000 more than men. "This study is one of the first to report a sex difference in the expression of a language-associated protein in humans or animals,” said Prof Margaret McCarthy, who led the study. In their study, the researchers attempted to determine what might make male rats more vocal than their female friends.

They separated four-day-old rats from their mothers and then counted the number of times they cried out in the “ultrasonic range”, the frequencies higher than humans can hear, over five minutes. While both sexes called out hundreds of cries, the males called out twice as often, they found. But when the pups were returned to their mother’s cage, she fussed over her sons first. Tests conducted on the parts of the brain known to be associated with vocalcalls showed the male pups have up to twice as much Foxp2 protein as the females. The researchers then increased the production in the brains of female pups and reduced it in males. This led to the female rats crying out more often and their mothers showing more interest to them. In contrast, males became less “talkative”.

The researchers then tested samples from ten children, aged between three and five, which showed that females had up to 30 per cent more of the Foxp2 protein than males, in a brain area key to language in humans.

“Based on our observations, we assume higher levels of Foxp2 in girls and higher levels of Foxp2 in male rats is an indication that Foxp2 protein levels are associated with the more communicative sex,” said Prof McCarthy.

"Our results imply Foxp2 as a component of the neurobiological basis of sex differences in vocal communication in mammals."

1.From the second paragraph, we can learn that ________.

A．women always speak more words than men

B．men and male rats have low levels of language protein

C．women and male rats have similar levels of Foxp2

D．McCarthy isn’t the first to find females more talkative

2.The underlined phrase “fussed over” in the third paragraph probably means______.

A．paid attention to    B．related to         C．put pressure on     D．counted on

3.The researchers carried out the experiments on rats in order to _______.

A．test which part of the brain is key to language in rats and humans

B．prove the levels of Foxp2 protein in humans and rats are different

C．determine the reason why female rats are more talkative than male rats

D．discover the association between Foxp2protein and vocal communication

4.Which of the following can be the best title for the passage ?

A．Tests on humans and rats                 B．Why women are the talkative sex

C．Sex differences in Foxp2 protein            D．Foxp2 protein determines oral ability

 

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