请输入或粘贴题目内容
搜题
拍照、语音搜题，请扫码下载APP
题目内容
（请给出正确答案）
How does the virus of a rabid animal infect man or other animals？
A．The virus is infected into their bodies.
B．The bite of the infected animals passes the virus presenting the saliva to others.
C．The virus has established in their central nervous systems for several years.
D．The virus infect them by some infectious diseases.
答案
更多“How does the virus of a rabid animal infect man or other animals？A．The virus is infected i”相关的问题
第1题
How does placebo work？
A．It fights the virus in human bodies.
B．It works through people's mental power.
C．It controls the hormones in human bodies.
D．It strengthens people's immune system.
第2题
—How much does a gold ring cost？ —It ______ the quality of the gold.
A．relies on
B．depends on
C．agrees on
D．comes on
第3题
听力原文：M: How much does this shirt cost？
W: Oh, they are on sale today. 30 dollars each or 50 dollars for two.
Q: How much does the man pay for two shirts？
(17)
A．30 dollars.
B．55 dollars.
C．60 dollars.
D．50 dollars.
第4题
How does the woman feel about the man's comment？
A．Pleased that the schedule was released on time
B．Annoyed that she is being asked to do pay money
C．Happy that an earlier problem has been corrected
D．Surprised that registration is so early in the year
第5题
How does the man feel about his new car？
A．We are not sure.
B．It's even worse than the old one.
C．It's much better than the old one.
第6题
听力原文：How often does your group meet？
(A) Okay, I'll see you at the meeting.
(B) Once a month.
(C) Upstairs at 3 o'clock.
(1)
A．
B．
C．
第7题
听力原文：W: How many classes do you have today？
M: Just one, from three to six.
Q: What does the man mean？
(18)
A．He will be in class all afternoon.
B．His class meets for three hours.
C．He has three classes in a row.
D．His class begins at one o' clock.
第8题
How much does Madam Li offer for the agent’s commission on these minimum quantities？
A．2% of the selling price of dyes.
B．2% of the price of all dyes.
C．2% of the revenues.
第9题
根据调查，一般企业改变自己的价格的频率如何？企业经理如何解释其价格的黏性？
According to surveys, how often does the typical firm change its prices？ How do firm managers explain the stickiness of their prices？
第10题
But what exactly is bird flu？ How is it different from the seasonal flu that people experience every year？ How does it threaten people？ What are governments doing to stop its spread？
Viruses and Influenza: An Overview
A virus particle--or virion--is a microscopic packet that contains genetic material wrapped in a layer of protein. Some viruses also have a lipid membrane(脂质膜)around the protein coat. Unlike bacteria, they cannot reproduce on their own--they have to invade host cells. This process destroys cells and makes people sick.
Viruses usually enter the bodies of animals and people through their mouths, mucus membranes or breaks in the skin. Then, they infect specific cells. For example, common cold viruses attack cells in the respiratory system. As they reproduce, they destroy their host cells, releasing copies of the virus to attack other cells. Some viruses are more stable than others, but in general they mutate frequently, sometimes making it difficult for doctors to treat them.
Influenza is a specific type of virus that attacks the respiratory system. It can cause fevers, sore throats and congestion. If it attacks muscle cells, it can also cause muscle aches.
There are three types of influenza virus--types A, B and C. Multiple subtypes exist within those types, and multiple strains(菌株)exist within each subtype. Like many viruses, influenza can mutate through antigenic drift(small changes that occur as it reproduces)or antigenic shift(major changes that create a new subtype of the virus).
Avian Flu
According to the United States Center for Disease Control and Prevention(CDC), birds carry every known subtype of influenza A. When scientists talk about avian flu, however, they usually mean varieties that exist mostly or entirely in birds--not in people. Most of the time, birds can't transmit the flu directly to people. They first infect pigs and other animals that can contract both human and avian flu strains. When the strains come into contact with one another, they create a new strain that infects humans.
Many wild birds carry avian flu in their intestines(肠)and shed the virus in their droppings, but they don't usually get sick from it. Domesticated birds, however, can get sick when they come into contact with contaminated(污染的)water, feed or soil. Birds spread the disease to each other through their saliva, respiratory secretions and droppings.
Avian flu is either low pathogenic(致病的)or high pathogenic. Low pathogenic strains cause very mild symptoms, like ruffled feathers and reduced egg production. High pathogenic strains, however, can be deadly--they often have a mortality rate approaching 100%. Birds that survive can continue to shed the virus in their droppings for ten days after recovering, which helps the virus continue to spread.
Avian Flu H5N1
In 1997, health officials in Hong Kong reported a virulent(致命的)strain of avian flu. For the first time, it appeared that the virus moved directly from birds to people instead of moving through a second species. The virus caused typical flu symptoms, and it also lead to eye infections, pneumonia and acute respiratory distress. Tests confirmed that this strain of the virus, influenza A H5N1, was completely new to humans.
Eighteen people infected with the virus were hospitalized, and six of them died. The Hong Kong government, alarmed at the potential thr
A．Y
B．N
C．NG
