A migraine(偏头痛)can cause disabling pain.People may not feel back to normal for hours or even days.Migraines are most common among young adults and middle-aged people.In the United States, about eighteen percent of women and six percent of men report having migraines.

People who suffer from migraines can find that different “triggers”(诱因)in different people may get a headache started.Stress can act as a trigger.So can chocolate in some people.Many migraine sufferers say hot weather and low barometric pressure(大气压)can act as triggers.But researchers say they did not have much scientific evidence of that — until now.

In a new study, a team examined the medical records of seven thousand hospital patients.The patients had visited the emergency room at Beth Israel Deaconess Medical Center in Boston, Massachusetts, because of a headache.More than two thousand of them had been found to have a migraine.

The team then compared those records to weather conditions in the twenty-four hours before the hospital visits.For every increase of five degrees centigrade in air temperature, the patients had a seven and one-half percent higher risk of migraine.Decreases in barometric pressure two to three days before the visit also appeared to trigger headaches.

The researchers found no evidence that air pollution influenced headaches.But they could not rule out the possibility of a smaller effect.

A separate study has found that age, gender and where a person has extra body fat may affect the risk of migraine.It found that overweight people between the ages of twenty and fifty-five may have a higher risk.On average, those who were larger around the middle were more likely to have migraines than those of the same age with smaller waistlines.

The study involved twenty-two thousand people.It was led by Lee Peterlin.She says early results suggest that losing weight in the stomach area may help younger people who experience migraines, especially women.

1.From the first paragraph, we can infer a migraine can      .

A.make people unable to walk

B.prevent people acting normally

C.cause people to leave home for days

D.get people to suffer from mental disorder

4.The underlined word “that” in Paragraph 2 refers to      .

A.chocolate acting as a trigger

B.stress acting as a trigger

C.hot weather and low barometric pressure acting as triggers 

D.high air pressure acting as a trigger

3.According to the passage, headaches are influenced least by      .

A.body weight        B.barometric pressure

C.air temperature      D.air pollution

4.In the opinion of Lee Peterlin, a person who has a migraine should      .

A.avoid gathering fat in the stomach area   

B.eat more sweet food every day

C.stay warm in good weather        

D.keep away from noisy places

5.Which of the following is TRUE according to the passage?

A.Overweight people may have a lower risk of migraines.

B.Weather is linked to migraines.

C.Migraines are a headache for many people

D.Women suffer fewer migraine than man do

 

A few years after World II finished, Scientists spoke with great eagerness about the use of nuclear(核) as source of energy. Within twenty years, they said, nuclear would take the place of coal, gas and oil as a source of power at home and in industry. This promise has never been carried out and there are serious doubts that it ever will be. Nuclear power plants are used to produce energy in some wealthier countries, but the cost is high.

Although safety measures have been taken, radiation leaks(辐射泄漏) have taken place and workers have been killed or affected. The problem of getting rid of the nuclear waste has proved most difficult. There is a limit to the mount of waste materials which can be buried in the ground or poured in the seabed. These methods may also cause more problems. Waste materials polluted by radiation may remain dangerous for 200 years or more.

It has no surprise that scientists have turned to the sun and the sea as sources of power. The sun shines day after day almost wastefully, providing us with energy far beyond all our earth.

1. The underlined word”source”means_______?

A. place from which something comes.

B. making use of

C. power plant.

D. a form.

2. Nuclear waste must be dealt with carefully, because______.

A. It still gives off energy      B. It’s much more expensive than coal, gas and oil.     C. It’s harmful to people’s health.  D. It can burn easily.

3. Which of the following statements is true?

A. It’s impossible to get rid of nuclear waste

B. Most of the nuclear water can be stored safely.  

C. Not all nuclear waste can be got rid of.

D. Nuclear waste can be replaced and reused easily.

4. The writer starts the last paragraph with “It has no surprise----”in order to_____.

A. tell us the danger of nuclear power.    

B. show there is plenty of sunshine.

C. Show that the energy of the sun can be made better use of       

D. tell us why scientists lost interest in nuclear power.

 

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