听力原文:F: Tom, do you know why Britain is separated form. the continent?
M: No. But I guess millions of years ago Britain was also a part of the Continent?
F: You are right. Nearly 10,000 years ago, at the end of the Ice Age, a great flood washed over a wide, low plain, and created the English Channel. From then on, the island of Britain was isolated from the rest of Europe.
N: I know there have been many people who have wanted to swim across the Channel, and some of them have succeeded.
F: What's more, quite a lot of people have thought of building a channel tunnel since the 18th century, but no one thought this dream would come true. Now, however, the channel tunnel, the longest underwater passage on the earth, has been built.
M: When was it built?
F: A British team started to drill southeast from Dover and a French team started to drill northwest from Sangatte in 1987. The two teams met under the channel in December 1990, and they celebrated the completion of the 23-mile shaft.
M: Was it opened to the public immediately?
F: No. The tunnel was opened to the public in 1993 and now it is able to carry up to 30 million passengers a year.
M: How long will it take to cross the Channel on the trains?
F: 26 minutes. In the past, people had to spend hours on the ferry in rough seas. So the tunnel is welcomed most warmly by all those who care for the future of Europe.
M: Yes. I think it serves to strengthen Britain's links with the continent and especially with France. It will further strengthen the exchange between peoples and thus lead to better understanding.
F: Surely it will.
How did the English Channel come into being?
A.Because of a flood 10,000 years ago.
B.Because of an earthquake 10,000 years ago.
C.Because of a flood 100,000 years ago.
D.Because of an earthquake 100,000 years ago.
第1题
A.白介素-12诱导Th0细胞向Th1方向分化
B.白介素-23促使Th17的增殖
C.白介素-12和白介素-23均含有白介素-12p40亚基
D.白介素-23趋化炎症初期中性粒细胞至反应部位
E.白介素-12激活自然杀伤细胞,使其产生干扰素-γ
第4题
A.转化生长因子-β1对Treg和Th17的分化都起到重要作用
B.白介素-2与转化生长因子-β1联合作用促进Treg分化,抑制Th17
C.白介素-6与转化生长因子-β1联合作用抑制Treg,促进Th17分化
D.白介素-2能激活STAT3,直接调节Foxp3基因,是Treg发育的关键分子
E.白介素-21和白介素-23均能激活STAT5,是Th17分化和发育必需的信号传导与转录激活因子
第5题
A.转化生长因子-1对Treg和Th17的分化都起到重要作用
B.白介素-2与转化生长因子-1联合作用促进Treg分化,抑制Th17
C.白介素-6与转化生长因子-1联合作用抑制Treg,促进Th17分化
D.白介素-2能激活STAT3,直接调节Foxp3基因,是Treg发育的关键分子
E.白介素-21和白介素-23均能激活STAT5,是Th17分化和发育必需的信号传导与转录激活因子
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