题目内容
In 1957 a doctor in Singapore noticed that hospitals were treating an unusual number of influenzalike cases. Influenza is sometimes called "flu" or a "bad cold". He took samples from the throats of patients and in his hospital was able to find the virus of this influenza.
There are three main types of influenza virus. The most important of these are types A and B, each of them having several sub-groups. With the instruments at the hospital the doctor recognized that the outbreak was due to a virus group A, but he didn't know the sub-group. He reported the outbreak to the World Health Organization in Geneva. WHO published the important news alongside reports of a similar outbreak in Hong Kong, where about 15%～20% of the population had become ill.
As soon as the London doctors received the package of throat samples, they began the standard tests. They found that by reproducing itself at very high speed, the virus had multiplied more than a million times within two days. Continuing their careful tests, the doctors checked the effect of drugs used against all the known sub-groups of type A virus. None of them gave any protection. This then, was something new; a new influenza virus against which the people of the world had no ready help whatsoever.
Having isolated the virus they were working with, the doctors now conducted tests on some specially selected animals, which contracted influenza in the same way as human beings did. In a short time the usual sign of the disease disappeared. Theses experiments revealed that the new virus spread easily, but that it was not a killer. Scientists, like the general public, called it simply "Asian" flu.
The influenza discovered by a doctor in Singapore is caused by ______.
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M: Well, I made a mistake about the room number anti stayed in room 415 for an hour waiting.
Q: What can we learn about Jerry？
(19)
SECTION C NEWS BROADCAST
Directions: In this section, you will hear several news items. Listen to them carefully and then answer the questions that follow.
听力原文： The world bank has put a loan of $215 million to help reconstruction of China's telecommunications system. The project will support Beijing's reform. effort in telecommunications and help increase its long-distance and local telephone capacity. Peter Right, the bank's telecommunications project engineer said China has shown dramatic and unprecedented growth in telecommunications, which, if it continues, will make this sector a case.
The number of long-distance calls in China grew by 42.2% from 1992 to 1997. But there are still some 1.6million people yet to receive it. The Chinese government has embarked on a program to expand and improve telecommunications with planned investment of about $250 million between now and 2004.
What peculiar problem is the telecommunications industry currently facing？
Sleepwalking is a disorder characterized by walking or other activities a person engaged in while【C1】______ still asleep. It is especially【C2】______ among children. Each night there are several【C3】______ of non-REM and REM sleep. Sleepwalking most often occurs during deep, non-REM sleep early in the night. It can also occur during REM sleep near morning.
The cause of sleepwalking in children is usually unknown【C4】______ may be related to fatigue, 【C5】______ sleep loss, or anxiety. Sleepwalking in adults can be associated with mental disorders, reactions to drugs and alcohol, or disease such as seizures: In the elderly, sleepwalking may be a 【C6】______ of an organic brain syndrome(综合病症) or REM behavior. disorders.
The sleepwalking activity may include simply sitting 【C7】______ and appearing to be awake【C8】______ actually being asleep, getting up and walking around, or【C9】______ activities such as【C10】______ furniture, going to the bathroom, dressing and undressing, and similar activities. Some people even drive a car while actually asleep. The【C11】______ can be very brief or can last for 30 minutes or longer.
One common misconception is that a sleepwalker should not be awaken. It is not dangerous to awaken a sleepwalker,【C12】______ the person may be【C13】______ or disoriented for a short time on awakening. Another misconception is that a person cannot be【C14】______ when sleepwalking. Actually, injuries caused by such things as tripping and loss of balance are common for sleepwalkers. Sleepwalking affects【C15】______ 1% to 17% of children and is more frequently seen in boys. The【C16】______ of sleepwalking decreases with age.
What causes sleepwalking is not known. Sleepwalking【C17】______ no serious health threat to those who experience it, although the risk of injury is a 【C18】______ of concern. Currently, there is nonspecific medical evidence that suggests that there may be psychiatric issues involved in sleepwalking and it is not【C19】______ or treated as a mental illness. Future research may【C20】______ the development of a medical-legal definition of sleepwalking.
【C1】
A．Family relations.B．Social problems.C．Family planning.D．Personal matters.
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