Sleeping in on Saturday after a few weeks of too little shuteye may feel refresh

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Sleeping in on Saturday after a few

weeks of too little shuteye may feel refreshing, but it can give a false sense of security.
New research shows long-term sleep loss cannot be cured that easily. Scientists researched the effects of short- and long-term sleep loss and found that those who suffer long-term sleep loss may function normally soon after waking up, but experience steadily slow

er reaction times as the day goes by, even if they had tried to catch up the previous night.
The research has important safety significances in an increasingly busy society, not just for shift-workers but for the roughly one in six Americans who regularly get six hours or less of sleep a night.
“We know that staying awake 24 hours without sleep will affect

your performance to do all sorts of things, and this effect equals to drinking too much when driving,” said lead researcher Dr. Daniel Cohen of Boston’s Brigham and Women’s Hospital. But when those who suffer long-term sleep loss become all-nighters, “the harm is increased ten times,” Cohen said.
The National Institutes of Health says adults need seven hours to nine hours of sleep for good health. Regularly getting too little sleep increases the risk of health problems, including memory impairment and a weakened immune system. More immediately, too little sleep affects reaction times; sleepiness is to blame for car crashes and other accidents.
It has critically important complicated and unexpected results for anyone who works “crazy hours” and thinks they are performing fine with a few hours of w

eeknight sleep, said Harris, director at New York’s Montefiore Medical Center. “Don’t think you can just bank up your sleep on the weekend, because it doesn’t work that way,” he warned.
小题1:The text mainly advises people ______.

A．to sleep more time	B．to sleep in on Saturday
C．to sleep scientifically	D．to sleep little on weekend

小题2:People with long-term sleep loss ______.

A．are quicker in thinking	B．may feel refreshed soon after waking up
C．are surely energetic	D．can have a strong sense of security

小题3:What can we learn from the text?

A．Most of the Americans get six hours or less of sleep a night.

B．Staying up is worse for those who suffer long-term sleep loss.

C．Traffic accidents have little to do with sleepiness.

D．One in six Americans are all-nighters.

小题4:Which of the following is the immediate effect of long-term sleep loss?

A．Health problems	B．Immune system
C．Reaction times	D．Memory impairment

小题5:The underlined phrase “bank up” in the last paragraph most probably means ____.

A．pile up

B．pick up

C．add up

D．build up

答案

小题1:C
小题2:B
小题3:B
小题4:C
小题5:A

解析

略

举一反三

D
Everyone knows you must exercise regularly to keep good health. Indeed, staying physically fit is a big part of our culture. we consider（or rightly so）that healthy people are attractive people. Since most of us want to be attractive, there is no shortage of exercise clubs, training videos, magazines and books offering to help us stay physically fit.
Unfortunately, however, our culture doesn’t place the same emphasis on mental fitness. Although we tend to like men and women with strong, healthy-looking bodies, we don’t have the same degree of respect or attraction for smart, educated, mentally healthy people. This is a pity, because there are great rewards for people who have developed the ability to think well.
If your mind is well trained and flexible, you will be able to understand a great deal of what ha

ppens around you. And if you are also well educated --- that is, if you understand basic science, mathematics, music, art, literature, history and so on --- you will find it much easier to make good decisions throughout your life. Over the long run, this leads to a sense of control over your destiny and a much better life than otherwise.
People who are poorly educated or who don’t think well --- that is, people who are not mentally fit --- see things differently. Their world is controlled by mysterious, often malevolent（恶意的）forces. Such people live within a system they will never master, forced to follow rules they will never understand. Although it may not be obvious, most spend their lives being manipulated（控制）by others. They are told what to do, what to think, how to spend their money, and what they should and should not aspire（渴望）to in life.
In my opinion, if you want to live well, you must be able to use your mind well. For this reason, I want you to be able to concentrate, to solve problems, to understand complex ideas, and to think clearly and quickly. Such skills will make it easier for you to make informed decisions, understand current events, choose good friends, manage your money well, make wise lone-term decisions and appreciate music, art and literature.
The key to developing such skills is to enjoy learning, and to have the ability and motivation to teach yourself.
63. The writer of the passage feel disappointed that ____.
A. too little has been done to help people to keep physically fit
B. too much has been done to help people to keep physically fit
C. mentally healthy people are not as popular as physically healthy people
D. physically healthy people are not as popular as mentally healthy people
64. The underlined word “this” in the 3rd paragraph means ____.
A. the understanding of a great deal of what goes on around you
B. the understanding of basic science and mathematics
C. good t

raining in body and mind
D. being able to make good decisions in life
65. The writer of this passage thinks those who are not mentally fit ____.
A. live a poor and mysterious life   B. can’t control over their life
C. often do what others do        D. enjoy being fooled and ruled
66. The best title of the passage will most probably be ____.
A. Train Your Body                  B. Train Your Mind
C. Make Informed Decisions       D. Think Hard and Work Hard

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A study published Monday found that people who sleep less tend to be fat, and experts said it’s time to find out if more sleep will fight fatness.
“We’ve put so much emphasis on diet and exercise that we"ve failed to recognize the value of good sleep,” said Fred Turek, a physician at Northwestern University.
Monday’s study from Eastern Virginia Medical School in Norfolk covered 1,000 people and found that total sleep time decreased as body mass index - a measure of weight based on height - increased.
Men slept an average of 27 minutes less than women and overweight and fat patients slept less than patients with normal weights, it said. In general the fatter subjects slept about 1.8 hours a week less than those with normal weights.
“Americans experience insufficient sleep and fat bodies. Clinicians are aware of the burden of fatness on patients,” the study said.
“Our findings suggest that major extensions of sleep time may not be necessary, as an extra 20 minutes of sleep per night seems to be associated with a lower body mass index,” it added.
“We caution that this study does not establish a cause-and-effect relationship between restricted sleep and fatness (but) investigations indicating success in weight loss via extensions of sleep would help greatly to set up such a relationship.”
The study was published in the Archives of Internal Medicine along with an editorial by Turek and Northwestern colleague Joseph Bass commenting on it and related research.
In an interview, Turek said some studies have shown sleep causes declines in an appetite suppressing protein hormone, and increases in another hormone that causes a longing for food. In addition neuropathies（神经疗法）in the brain governing sleep and fatness appear to overlap（重叠）, he said.
Patness has been rising dramatically in developed countries and reached epidemic（流行病） levels in the United States, it added, leading to a variety of health problems.
66. What’s the passage mainly about?
A. People who sleep less tend to get fat.
B. Fat people need lots of sleep to lose weight.
C. Sleeping has nothing to do with fatness.
D. Fatness has been rising dramatically in developed countries.
67. According to the passage, which of the following is TRUE?
A. Lack of sleep causes declines in a desire limiting protein hormone.
B. Americans experience sufficient sleep and fat bodies.
C. The findings suggest that major extensions of sleep time may be necessary.
D. Fatness has been rising dramatically in America.
68. Which of the following is NOT close to the underlined word suppress?
A. limit          B. restrict       C. accept         D. control
69. According to the passage, which of the following people is the lowest possible one to get fatness?
A. Americans      B. Chinese        C. Japanese       D. English
70. We can conclude the attitude of the author is           according to the passage.
A. worried        B. uninterested   C. critical       D. optimistic

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The beet (甜菜) is a tasty root vegetable that does not require much work to grow. People think of beets as being always dark red，but they can also be pink，yellow or white. Beets are high in nutrients，and both the root and the tops can be eaten. The leaves make good salads when the plants are young，and the greens can be cooked when the plants are older. Beets grow best in full sun and in loose soil that is not too wet.
Remove stones from the soil while preparing the ground，and test it before adding fertilizer Beet seeds can be planted as soon as the soil can be worked at the start of the growing season. Planting them every two or three weeks will provide a continuous harvest into the fall. A beet seed is a fruit containing several seeds. Overcrowding the plants will mean that the roots cannot spread out and grow，so thin the beets by removing the smaller ones and using them as greens.
A specialist named Cindy Haynes says little or no fertilizer is needed in rich soils. Once the seeds are planted，however，she suggests covering the soil to protect it from the rain and during dry periods. She also suggests putting a fence around the plants to keep away rabbits and deer. She says the only work beets need once they have been thinned is weeding and， when the weather is dry，a weekly watering. For best results，beets should be picked when the roots are two and one-half centimeters around. Larger beets can be tough，and have to be cooked for a long time. Beets can be eaten in many ways.
60.What is the second paragraph mainly about?
A. How to test the soil.           B. How to plant beets
C. When to harvest beets.          D. When to plant beets.
61.Smaller beets are often removed in order to       .
A. give other beets space to grow    B. add more fertilizer to the soil
C. plant new seeds                D. use the green，young leaves in salads
62.What may the next part of the last paragraph be about?
A. When to pick beets.             B. How to eat beets.
C. The uses of beets.              D. The taste of larger beets.
63.The passage is most probably from a(n)     .
A. gardening book   B. education magazine   C. science report   D. entertainment magazine

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Peanut allergies (过敏) are among the most common and most dangerous of food allergies. A tiny exposure to peanuts can mean big trouble for a person with a peanut allergy—not just sneezing or coughing，but something as potentially deadly as narrowing of the airways.
But a recent study suggests that some children may be able to beat back their allergic reactions to peanuts by gradually introducing trace amounts of the nut into their diets. It"s too early to say for certain，so if you have a peanut allergy，do not try this at home. But the first results look promising.
Two teams of scientists have been experimenting on a group“of 29 children who are allergic to peanuts”At the beginning of the study，each kid received less than 1/1，000 of a peanut per day. (Imagine splitting a peanut into 1，000 parts!) Over the course of the study， the children gradually increased the amount of the peanut in their diets
Nine of the children have been receiving the treatment for two years，and five of those nine now appear to be free of their peanut allergies，and can eat peanuts with no problem. But the other four have not benefited so much from the therapy（治疗）.
The two teams of scientists are now doing a follow-up study on two groups of children with the allergy. Children in one group will receive the new therapy，while the others will not. Researchers hope this study will help them learn if the therapy truly does work.
Scientists don"t understand why some people get peanut allergies and others don"t，but are trying to find a way to help people with the allergy. Because of the severity of some peanut allergies，scientists want to know the answer as soon as possible. “This is very encouraging， but remember，it"s not something you try at home，”says one of the researchers.
68.According to the passage，the peanut allergy     .
A. can be deadly if only a small amount is used
B. causes a lot of trouble for many parents
C. allows people to eat only small amounts of peanuts
D. is considered the least common and dangerous food allergy
69.Scientists are trying to treat peanut allergies by     .
A. exposing children with the allergy to as many peanuts as possible
B. changing the eating habits of children with peanut allergies gradually
C. giving children Peanuts in slowly increasing amounts
D. exploring ways to resist the feelings caused by peanut allergies
70.The experiment shows that     .
A. people with peanut allergies can"t use small amounts of peanuts in their diets.
B. children are more easily cured than adults
C. all children can be cured of their peanut allergies if given more time of treatment
D. about 55-percent children with peanut allergies have been cured
71. Scientists are now doing a follow-up study in order to     .
A. explore why some people get the illness while others don’t
B. show whether peanut allergies can really be dangerous
C. check whether the therapy really works or not
D. explore whether the allergy can be cured without treatment

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When people lose legs after accidents or illnesses, emergency care and artificial limbs（假肢）often allow them to walk again. Newts （蝾螈） in the same situation, on the other hand, can grow limbs back on their own! Scientists have known for a long time that certain animals can re-grow limbs, but they haven’t quite figured out how these creatures do it.
Researchers have now come up with some new ideas. Their work may give people the ability to re-grow lost limbs. The researchers started with two simple experiments：when you cut a newt’s leg at the ankle, only the foot grows back；when you cut off a leg at the very end, the whole leg grows back. In both cases, the re-growth begins with stem cells. Stem cells can develop into nearly any type of cell in the body.
How do a newt’s stem cells know when to grow only a foot and when to re-grow a whole leg?
This question relates to another mystery. In newt’s, a cut-off leg will grow back only if the nerve bundle（神经束）in it also grows back , but if something prevents the nerve bundle from growing, the stem cells at the wound won’t re-grow a new leg.
In its study, a British team focused on a protein called n-AG. When the team prevented nerves in a limb from growing, but added the n-AG protein to stem cells in the limb, the limb still re-grew. That protein seems to guide limb re-growth. People have proteins that are similar to n-AG. Further research into these materials may someday help human limbs recover by themselves.
40. In the experiments, the researchers cut off a newt’s foot or leg to find out _____.
A. what stem cells were                    B. whether they would grow back
C. how long it would take to re-grow    D. how they would re-grow
41. A newt will re-grow its leg if _____.
A. its ankle was cut off but the nerve bundle was good
B. its leg was cut off and the nerve bundle stopped growing
C. its leg was cut off and the nerve bundle could grow back
D. its ankle and the nerve bundle were cut off
42. What do the underlined words “these materials” refer to?
A. Nerve bundles and proteins.         B. Proteins similar to n-AG.
C. Stem cells and proteins.              D. Stem cells and nerve bundles.
43. The first sentence of the passage _____.
A. acts as a lead–in                      B. shows where researchers got their new ideas
C. states the author’s opinion           D. describes the result of researchers’ studies

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