问题 单项选择题

关于阿尔茨海默病(AD)的病因学、发病机制,以下错误的是()

A.AD患者脑部乙酰胆碱明显缺乏,乙酰胆碱酯酶和胆碱乙酰转移酶活性降低

B.AD患者脑中某些神经递质的含量一般减少,如去甲NE、5-HT、谷氨酸等

C.AD患者发病与遗传因素有关,有家族史者其患病率比普通人群高

D.载脂蛋白E4(APOE4)基因是老年型AD的重要危险基因

E.80%左右的AD患者为家族性常染色体显性遗传(FAD.的患者

答案

参考答案:E

阅读理解

根据短文内容,判断下列句子正(T)误(F)。

      We use the Internet every day, but do you know the history of the Internet?

      Many people were surprised when they found that the Internet was set up in the 1960s. At that time,

computers were large and expensive. Computers didn't work well. If one computer in network Broken down,

then the whole network stopped. So a new network system had to be set up. It should be good enough to be

used by many different computers. If one part of the network was not working information could be send

through another part. In this way the computer network system would keep on working all the time.

    At first, the Internet was only used by the government, but in the early 1970s universities, hospitals and

banks were allowed to use it, too. However, computers were still very expensive and the Internet was

difficult to use. By the start of the 1990s, computers became cheaper and easier to use. Scientists had also

developed software (软件) that made "surfing the Internet" more convenient. 

    Now it is easy to get online and it is said that millions of people use the Internet every day. Computers

are becoming much cheaper and smaller. The invention of the laptop makes people be able to use computers

everywhere. Sending e-mail is more and more popular among students and other young people. The Internet

has now become a very important part of people's life.

( )1. The Internet was set up about more than sixty years ago.                       

( )2. In computers were expensive and not convenient enough to use at the beginning. 

( )3. In the early 1970s only the government used the network.                       

( )4. Sending e-mail is more and more popular among old people.                      

( )5. Now the Internet is connected with people's life.                              

单项选择题 A型题