A chemical important of brain development may play a role in explaining why some people are genetically (由基因决定地) 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(药物镇静), 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
6. 解析：选D。细节理解题。从第二段可知，随着fibroblast growth factor 2的减少，老鼠就会变得更加焦虑；如果FGF2增加的话，老鼠就会变得安静一些。故D项正确。
7. 解析：选B。细节理解题。从第二、六段的介绍可知，改善老鼠的生活环境可以使焦虑的老鼠变得安静一些，故B项正确。
8. 解析：选D。指代题。从第四段可知此处的it指代大脑，故答案为D。
9. 解析：选B。推理判断题。从最后一段中“This discovery may pave the way for new, more specific treatments for anxiety that will not be based on sedation, but will instead fight the real cause of the disease”可推知，这项实验为医生治疗焦虑症提供了更好更有效的办法，故选B项。
综合自测系列答案科目：高中英语 来源： 题型：阅读理解
Animals can move from place to place ,but plants cannot. When an animal is under attack ,it can run away or fight back .Plants certainly cannot run away ,and they lack teeth and claws .But plants can defend themselves by using both physical and chemical means.
Some plants have their own ways to keep animals away .For example ,the leaves of the holly plant have sharp spines（刺）that discourage grass-eating animals .Holly leaves on lower branches have more spines than leaves on upper branches .This is because the lower leaves are easier for most animals to reach.
Some plants ,such as the oak tree, have thick and hard leaves that are difficult for animals to eat .Some grasses may contain a sandy material ,eating such grasses wears down the animal’s teeth .
Many plants also have chemical defenses .Some plants produce chemicals that taste bitter or cause an unpleasant reaction. Some plants may fight against an attack by increasing the production of these chemicals .When a caterpillar（毛虫）bites a tobacco leaf ,the leaf produces a chemical messenger .This messenger sends to the roots the information to produce more nicotine .The higher levels of nicotine discourage the caterpillar.
Many plants depend on both physical and chemical defenses. A certain plant in China ,for instance, has prickly （多刺的）leaves, and each prickle contains poisonous venom（毒液）A single experience with this kind of plant will teach an animal to stay away from it in the future.
68．The holly plant has more spines on the lower leaves because most animals .
A．are not tall enough B．like the lower leaves only
C．are not clever enough D．can get the lower leaves easily
69．To defend themselves ,oak trees use .
A．chemical means B．physical means
C．bitter chemicals D．sandy materials
70．How does tobacco protect itself against an attack from a caterpillar?
A．Its leaves fight against the attack by physical means.
B．Its roots send a messenger to discourage the caterpillar.
C．Its roots increase the production of nicotine when it is attacked.
D．Its leaves produce poisonous sand to drive the caterpillar away.
71．What would be the best title for this passage?
A．Plants and Animals B．How Plants Defend Themselves
C．Attacks and Defenses D．How Animals Eat Plant Leaves
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科目：高中英语 来源：2013届辽宁省五校协作体高三上学期期初联考英语试卷（带解析） 题型：阅读理解
Since ancient times, people have known about its ability to reduce pain and high body temperature. More than 2000 years ago, the Greek doctor Hippocrates advised his patients to chew on the bark and leaves of the willow.
The tree contains a chemical called salicin（柳醇）. From salicin, researchers in the 1800s discovered how to make salicylic acid（酸）. And in 1897, a chemist named Felix Hoffmann at Friedrich Bayer and Company in Germany created acetyl salicylic acid. Later it became the active substance in a new medicine that Bayer called aspirin. The "a" came from acetyl. The "spir" came from the spirea plant, which also produces salicin. And the "in" Well, that is a common way to end medicine names.
In 1982, a British scientist shared the Nobel Prize in Medicine in part for discovering how aspirin works. Sir John Vane found that aspirin blocks the body from making natural substances called prostaglandins（前列腺素）.Prostaglandins have several effects on the body. Some cause pain and the expansion, or swelling（ 肿瘤; 膨胀）, of damaged tissue. Others protect the lining of the stomach and small intestine. Prostaglandins also make the heart, kidneys and blood vessels （血管）work well. But there is a problem. Aspirin works against all prostaglandins, good and bad. Scientists learned how aspirin interferes with an enzyme（酶）. One form of this enzyme makes the prostaglandin that causes pain and swelling. Another form of the enzyme creates a protective effect. So aspirin can reduce pain and swelling in damaged tissues. But it can also harm the inside of the stomach and small intestine（肠）.
【小题1】What sickness can the medicine from the willow deal with according to the passage?
| A．Cold | B．Toothache | C．Cancer | D．Skin disease |
| A．It results from pain. |
| B．It prevents the lining of the stomach and small intestine. |
| C．It causes blood vessels to work wrongly. |
| D．It is sometimes good but sometimes bad. |
| A．Aspirin can treat almost diseases. |
| B．Aspirin can create the protective enzyme. |
| C．Aspirin can harm the inside of the stomach and small intestine. |
| D．Aspirin can protect the inside of the stomach and small intestine. |
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科目：高中英语 来源：广东省广州市2010届高三下学期综合测试（二） 题型：阅读理解
Ⅲ 阅读 (共两节，满分40分）
第一节阅读理解(共15小题；每小题2分，满分30分)
阅读下列短文，从每题所给的A、B、C和D项中，选出最佳选项，并存答题卡上将该
项涂黑。
(A)
Increasingly over the last few years,we have become familiar with the range of small electronic devices or “smart” accessories (附件,饰品 ) . Pocket heart -rate monitors for joggers and electronic maps are just the first examples of many new products that promise to change our lives in all sorts of surprising ways.
As a scientist at New York University . Rosalind Picard tries out different smart accessories before they go on the market. One of these was the so-called " frown (皱眉)headband". Rosalind was shocked to realize just how often she frowned. Stuck in a traffic jam recently, Rosalind kept hearing the sounds of the tiny sensor inside the band worn around her forehead -each time she frowned in annoyance, the sensor gave out a signal.
Another computer scientist , Stevcn Feiner, is working on a pair of glasses that will do more than help you to see .Imagine you want to try a restaurant in a foreign city but you're not familiar with the dishes on the menu. If you are weanng a pair of Steven's glasses . all yau have to do is glance above the restauran’s doorway and your glasses will immediately become windows to the Tntemet, offering you full details of the meals served inside. The glasses could also be used to help people make speeches,give chefs access to the latest recipes and even provide doctors with
patient information while they carry out operations.
At the moment, Steven's invention looks more like a large ski mask than a pair of glasses.
It's a headset connected to a hand-held computer and a Global Positioning System ( GPS ) receiver, which tracks the wearer's position. But he says that these head-worn displays will eventually get smaller and lighter as technology improves.
And, of course, this new technology has a fashionable as well as a useful application. A chemical engineer named Roben Langer has invented a new microchip that, if put inside a ring,can give off different smells according to a person's mood. That, of course, may or may not appeal to you. And,in the end , it is shoppers . not scientiscs , who will determine which of these smart accessories will succeed as fashionable items and which are sure tO join history's long list of crazy inventions.
It is clear,however ,that as computers get smaller and cheapcr. Lhcy will pop up in all sorts
of easily-wearable accessories . even in the buttons on your coat. WhaCs morc, this is something that's going to happen a lot sooner than we all expect.
41. When Rosalind wore the headband, she was surprised a___________
A. how well the sensor worked B. how she was affected by traffic
C. how strong the signal was D. how uncomfortable it was
42. For people eating out , Steven’ s glasses can___________
A . give them a restaurant's location
B. let them see a restaurant's environment
C. inform them about a restaurant’s menu
D. tell them about a restaurant's quality
43. What is the current problem with Stevcn's glasses?
A. Limited function. B. Inconvenience.
C. High cost. D. Poor Internet access.
44. In general, what does the writer think about smart accessories?
A. They will soon be widely available.
B. Much more research is needed into them.
C. Only a few of them will appeal to shoppers.
D. Most of them are considered to be crazy inventions.
45. What's the writer's purpose in writing this passage?
A. To advertise some smart accessories.
B .To tell interesting stories about smart accessories.
C. To argue that smart accessories are fashionable.
D. To introduce the idea of smart accessories.
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科目：高中英语 来源：广东省深大附中2009-2010学年度高二第一学期期末联考 题型：阅读理解
Recently, a survey was done among 288,000 students, which shows that today’s traditional-age college freshmen are “more materialistic and less altruistic (利他主义的)” than at any time in the 19 years of the poll (民意调查).
Not surprisingly, in these hard times, the students’ major purpose “is to be financially well off. Developing a meaningful philosophy of life is less important than ever.” It follows then that today the most popular course is not literature or history but accounting.
Interest in teaching, social service and the “altruistic” fields is at a low. On the other hand, enrollment in business programs, engineering and computer science is way up.
That’s no surprise either. A friend of mine (a sales representative for a chemical company) was making twice the salary of her college instructors in her first year on the job---even before she completed her two-year associate degree.
Though it’s true that we all need a career, it is equally true that our civilization has accumulated an incredible amount of knowledge in fields far beyond our own and that it will be better for our understanding of these other contributions—either scientific or artistic.
Similarly, it is true that, in studying the diverse wisdom of others, we learn how to think. More importantly, perhaps, education teaches us to see the connections between things, as well as to see beyond our immediate needs.
Weekly we read of unions who went on strike for higher wages, only to drive their employer out of business. No company; No job. How shortsighted in the long run!
But the most important argument for a broad education is that in studying the accumulated wisdom of the ages, we improve our moral sense. I saw a cartoon recently which shows a group of businessmen looking puzzled as they sit around a conference table; one of them is talking on the intercom (对讲机) : “Miss Baxter,” he says, “could you please send in someone who can distinguish right from wrong?”
From the long-term point of view, that’s what education really ought to be about.
51. According to the result of the survey, college students _______________.
A. take developing a meaningful philosophy of life more seriously
B. have a wide range of knowledge in many aspects
C. pay more attention to the study of literature
D. have never been so materialistic as today
52. The students’ criteria (标准) for choosing their majors today are largely based on _________.
A. their own understanding of the courses
B. the financial goals they seek in life
C. the influence of their instructors
D. the vast potential for the future educational development
53. What does the fifth paragraph imply?
A. Knowledge in other fields has nothing to do with one’s career.
B. Business management should be included in educational programs
C. The importance of a broad education should not be ignored
D. A good understanding of the civilization will make students rich.
54. The author’s attitude to the effect of studying the diverse wisdom of others is ______________.
A. positive B. indifferent C. doubtful D. negative
55. The writer wrote the passage in order to indicate that ______________.
A. college students today are not a diligent generation
B. people engaged in technical jobs lead a more meaningful life
C. career seekers shouldn’t focus on immediate interests only
D. working experience outside college counts a lot to one’s future career
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科目：高中英语 来源：2015届湖北省高一上学期期中考试英语试卷（解析版） 题型：阅读理解
The deadly earthquake and tsunami (海啸) that struck Japan on March 11 damaged two nuclear power stations. Officials are now working to prevent dangerous radiation from poisoning the air in the area surrounding the Fukushima Daiichi plant. The Japanese government has ordered people living within 12 and a half miles of the plant to evacuate, and asked those living 12 and a half to 20 miles away to stay indoors.
Nuclear power plants create energy using a chemical reaction that produces large amounts of heat. Reactors(反应堆)in Japan have many long, thin rods, called fuel rods(棒), which must be kept cool.
If the reactor’s fuel rods aren’t cooled, the reaction can burn out of control. That’s what happened at the two Japanese plants after the quake caused a power failure and the cooling systems malfunctioned(发生故障). This overheating could cause radiation to escape and sicken many people.
Japan’s 54 nuclear reactors are built to withstand the many small or moderate earthquakes the country faces each year. But Friday’s earthquake was one of the most severe earthquakes ever recorded.
People exposed to unsafe levels of radiation have a higher than normal risk of getting cancer. The Japanese government has been distributing potassium iodide(碘化钾)pills to people in the surrounding areas to protect those who may have come in contact with radiation from the power plant. The pills flood the body with healthy potassium iodide. The potassium iodide works to crowd out “bad” iodine in the body that may have been poisoned by radiation.
On Tuesday morning, 750 workers left the Fukushima Daiichi plant. However, 50 workers stayed behind to use sweater to cool the fuel rods. These dedicated employees are risking their own lives to save many others.
On Thursday, officials used helicopters, fire trucks, and water cannons to spray water on the reactors to cool the fuel rods. But it’s not clear whether these efforts were successful. Officials are now working on a power line to restore electricity to the plant. They hope this will help restart the plant’s cooling system and stop the fuel rods from leaking radiation.
1.The underlined word “evacuate” in Paragraph 1 probably means .
|
A．help |
B．rest |
C．stop |
D．leave |
2.What can we learn from the text?
|
A．The local people are scared and ready to run away. |
|
B．The earthquake led to many deaths and caused damage to roads. |
|
C．The Japanese government has found a kind of pill that can treat cancer. |
|
D．The two stations were damaged because their cooling systems didn’t work. |
3.In the last paragraph, the author mainly states .
|
A．lack of help |
|
B．international aids |
|
C．the government’s efforts |
|
D．the result of the disaster |
4.This text is most probably taken from .
|
A．a research paper |
|
B．a newspaper report |
|
C．a class presentation |
|
D．a chemistry textbook |
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