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

Once again, I was in a new school. So was a girl in my class named Paris. That's where the similarities ended.

I was tall and she was small. My thick, black hair had been recently cut short. Her natural blonde hair flowed to her waist and looked great. I was awkward and shy. She wasn't. I couldn't stand her. I considered her my enemy. She liked me. She wanted to be friends.

One day, she invited me over and I said yes — I was too shocked to answer any other way. No one had invited me over to play. But this girl who wore the latest fashions wanted me to go home with her after school.

I got very surprised when she led me into an apartment building. She lived on the fourth floor in a two-room place with her mother, her stepfather, her two brothers and her sister.

When we got to the room she shared with her sister, she took out a big case of Barbies — which was my next surprise. I would have thought she'd outgrown them. I had never played with them. But we sat on the floor of a walk-in closet, laughing as we made up crazy stories about the Barbies. That's when we found out that we both wanted to be writers when we were older and we both had wild imaginations.

We had a great day that afternoon. Our jaws ached from smiling so much. She showed me her wardrobe, which had mostly come from a designer clothing store down the block. The woman who owned it used her as a model sometimes for her newspaper ads and gave her clothes in exchange.

Paris had the whole neighborhood charmed. The bookstore owners lent her fashion magazines, the movie theater gave her free passes and the pizza place let her have free slices. Soon I was included in her magic world. We slept over at each other's houses, spent every free moment together. My dark hair grew out and I learned to love being tall.

Paris, my first real friend since childhood, taught me an amazing and very surprising thing about making friends: that your worst enemy can turn out to be your best friend.

1.The writer and Paris were similar in that      .

A. they were both new students

B. both of them were friendly

C. both of them were tall

D. they were both the youngest in class

2.In the article the writer described Paris as a girl who was      .

A. awkward and shy  B. fashionable and proud

C. quiet and lonely  D. friendly and lovely

3.What did the writer learn from Paris?

A. How to make best use of her neighborhood.

B. How to dress and look fashionable.

C. How to become a good writer

D. How to make friends.

4.From the article, we can see that through her friendship with Paris, the writer      .

A. found she and Paris had more similarities than differences

B. was able to fit in at her new school with Paris’ help

C. was not so awkward or shy as before

D. learned more about fashion herself

 

That year , in the local school, there was a new math teacher, as well as some new pupils. One of the new kids was the stupidest child anyone had ever seen. It made no difference how quickly or how slowly they tried explaining numbers to him; he would always end up saying something enormously stupid. Like two plus two was five, seven times three was twenty-seven, or a triangle had thirty corners……

Before this boy arrived, math lessons had been the most boring of all. Now they were great fun. Encouraged by the new teacher, the children would listen to the pieces of nonsense spouted by the new kid, and they would have to correct his mistakes.

Whenever the new teacher asked questions, the stupid kid would stand up but made the wrong answers, the other students all wanted to be the first to find his mistakes, and then think up the most original ways to explain them. To do this they used all kinds of stuff : sweets, playing cards, oranges, paper planes, etc. It didn’t seem like any of this bothered the new kid.

However, Little Lewis was sure that it was bound to make him feel sad inside. Lewis was sure he would see him crying. So, one day, he decided to follow the new kid home after school. On leaving school, the new kid walked a few minutes to a local park, and there he waited for a while, until someone came along to meet him……

It was the new teacher!

The teacher gave the new kid a hug, and off they went, hand in hand. Following from a distance, Lewis could hear they were talking about math.

1.The math lessons became interesting again because of the new teacher’s ___________.

A. creativity    B. imagination    C. responsibility     D. curiosity

2.The passage implies that the stupidest child____________________________.

A. was in great need of math teacher’s help after class

B. knew much more about math than other classmates

C. had no much gift for math and was slow to learn it

D. disliked both the new math teacher and his lessons

3.According to the passage, Lewis followed the stupidest in order to ______________.

A. learn about where he lived           B. find out if he felt upset

C. say something to comfort him         D. make friends with him

4. What does the underlined word “this” in the third paragraph refer to ?

   A. To find the stupidest kid’s mistakes.

   B. To think up the most original ways to explain.

   C. To use all kinds of stuff.

   D. To follow him home after school.

 

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