题目内容
In 1971, a study of 700 children, ages 2 to 14, used a special blood pressure recorder which minimizes observer error and allows for standardization of blood pressure readings. Before then, it had been well established that the blood pressure of adults aggregates familially, that is, the similarities between the blood pressure of an individual and his siblings are generally too great to be explained by chance. The 1971 study showed that familial clustering was measurable in children as well, suggesting that factors responsible for essential hypertension are acquired in childhood. Additional epidemiological studies demonstrated a clear tendency for the children to retain the same blood pressure patterns, relative to their peers, four years later. Thus, a child with blood pressure higher or lower than the norm would tend to remain higher or lower with increasing age.
Meanwhile, other investigators uncovered a complex of physiologic roles-including blood pressure-for a vasoactive (作用于血管的) system called the kallikrein-kinin (血管舒缓酶-激酞原 ) system. Kallikreins are enzymes in the kidney and blood plasma which act on precursors (先兆) called kininogens to produce vasoactive peptides(酞)called kinins. Several different kinins are produced, at least three of which are powerful blood vessel dilators. Apparently, the kallikrein-kinin system normally tends to offset the elevations in arterial pressure that result from the secretion of salt-conserving hormones such as aldosterone(醛固酮) on the one hand and from activation of the sympathetic nervous system (which tends to constrict blood vessels) on the other hand.
It is also known that urinary kallikrein excretion is abnormally low in subjects with essential hypertension. Levels of urinary kallikrein in children are inversely related to the diastolic blood pressures of both children and their mothers. Children with the lowest kallikrein levels are found in the families with the highest blood pressure. In addition, black children tend to show somewhat lower urinary kallikrein levels than white children, and blacks are more likely to have high blood pressure. There is a great deal to be learned about the biochemistry and physiologic roles of the kallikrein-kinin system. But there is the possibility that essential hypertension will prove to have biochemical precursors.
The author is primarily concerned with ______.
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听力原文： During the Orange Revolution, Viktor Yushchenko's name echoed across Kiev's Independence Square as hundreds of thousands of Ukrainians reversed a fraudulent presidential election and put Mr. Yushchenko in office. But after just nine months, the President's Chief of Staff resigned, after leveling corruption charges against the highest levels of the new administration. The ensuing crisis has disenchanted many in Ukraine.
Expressing disappointment with politicians, however, is something ordinary Ukrainians did not have freedom to do in the past. For centuries, Ukrainian political rivalries were hidden from the public or led to bloody social upheavals. According to Ukrainian historian Orest Subtelny of York University in Toronto, Canada, the current crisis is unusual in Ukraine's history, but not in the history of democracies.
According to the news, the ordinary Ukrainians ______ to express their disappointment with politicians.
What is the message delivered by the IRA in a statement at the end of July？
SECTION B INTERVIEW
Directions: In this section you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. Questions 1 to 5 are based on an interview. At the end of the interview you will be given 10 seconds to answer each of the following five questions.
Now listen to the interview.
听力原文： (I — Interviewer; B — Mrs. Bruce)
I: I'm going to talk to you now about the suffragette movement. Were you yourself ever a suffragette, Mrs. Bruce？
B: No, I did not approve of suffragettes. I did not want to have the vote. I felt the man of the house should be in charge of that section. And the woman, of course, to look after the home and the children, to be a good wife and mother. I think that voting was unnecessary, because politics was quite far from us women at that time. But I'm not going to say now, that perhaps it has had its advantages.
I: How common was your attitude at the time that the suffragettes were being militant？
B: Oh, I was very much against them. I didn't understand why they out to be so aggressive at some time. I'd be highly insulted if anybody called me a suffragette. I remember walking with my governess down Downing Street just past Number 10 and they chained themselves to the railings. Of course, I had a good laugh but I thought it wasn't going to be me.
I: Were they a popular movement in their day？
B: Well, with a certain number of course. And they tried very hard and eventually they got the vote, er through their efforts, so I suppose their efforts were good in quite a lot of ways, which I wasn't able to see in the past. Er, I think women in Parliament — there aren't many, but those who've been there have done a lot of good. As a matter of fact, to some extent, we are benefiting today from what they've achieved.
I: So you think in the long term...
B: In the long term, no harm was done. As long as their demonstrations were peaceful.
I: Do you think it would matter very much if women didn't, hadn't achieved the vote, if they hadn't got the vote at all and still didn't have it？
B: I don't think it would've made a great deal of difference, no, but there are certain things they've done — those that have been Members of Parliament — that have been very useful in helping women in their jobs, in other vocations. I think it's good that it happened. But I wish it happened a little bit more peacefully, perhaps. There might have been more changes in women's life if so.
I: What sort of things can you remember？ What other sorts of demonstrations do you remember？
B: Marching, they were marching everywhere. But of course those were much more peaceful days; nobody interfered with their marches. There were a few boos here and there and a lot of clapping. Everyone was very excited. Yes.
I: Did you, did you actually, know any suffragettes yourself？
B: Well, my friends, my close friends, were not suffragettes but I had one or two friends, not very close friends that were. And we used to have great arguments and I used to say I didn't want the vote, I don't want to vote.
I: How did they react to that？
B: They didn't like that. They said I ought to join the movement, and told me a lot of examples, but I said, no I don't want to vote.
I: But, and yet you've done so many exciting things. You've done so many things that in your day, were probably the exclusive preserve of the man.
B: Well, yes. But voting didn't make any difference because that's a political thing, voting, I never, I don't care about women entering into politics particularly. Ah, no harm's been done with the few that have entered the House of Commons but, in fact, some have done a great deal of good. But that's quite different to beating men at their own job. Now that's nothing to do with votes. Now, for instance, I always got a great thrill on the race track at Brooklands, if I could beat, well, Sir Henry Seagrave, for instance, in a race, I never did beat him but
设有关系S(SNO,SNAME,SEX) ,C(CNO,CNAME) ,SC(SNO,CNO) 。其中SNO为学号，SNAME为学生姓名，SEX为性别，CNO为课程号，CNAME为课程名。要查询选修“计算机”课的全体女学生姓名的SQL语句是SELECT sname FROM S,SC,C WHERE子句。这里WHERE子句的内容是
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