简述通行与不通行管沟的选择标准。

患者，52岁，近半年来常于劳累后感疲乏，伴劳力性呼吸困难和发作性心前区闷痛，休息后稍好转。外院诊断为“心律失常第二度Ⅱ型房室传导阻滞”，治疗情况不详。半天前，患者在超市购物时突然发生晕厥，伴抽搐，查体：心率30次／分，血压85／55mmHg。急诊以“晕厥待查”收入院。

第二度Ⅱ型房室传导阻滞心电图的特点是（）。

A.P–R间期大于0.02秒，无QRS波群脱落

B.P–R间期逐渐延长，直至QRS波群脱落

C.P–R间期固定且正常，有间断性的QRS波群脱落

D.P–R间期固定且延长，有间断性的QRS波群脱落

E.P–R间期固定，可正常亦可延长，有间断性的QRS波群脱落

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One day Mr. Kerry was walking along the Strand in London, killing time, when his eye was caught by an enormous picture displayed upon the wall of a house. It represented a human figure covered with long, dark hair, with huge nails upon his hands and a most fearful expression. On coming nearer, he heard a man call out 'Walk in, ladies and gentlemen, the most wonderful curiosity ever exhibited-only five pence-the wild man from Africa-he eats raw food, and many other pleasing and surprising performances. Mr. Kerry paid his money and was admitted. At first the crowd prevented his seeing anything, for the place was full of suffocation(窒息), and the noise was awful. At last, Mr. Kerry obtained, by dint of squeezing and pushing, a place in the front, when to his horror, he saw a figure that was far worse than the portrait outside.

It was a man, nearly naked, covered with long, shaggy hair, that grew even over his nose and cheekbones. He sprang about, sometimes his feet, sometimes on all-fours, but always uttering the most fearful yells, and glaring upon the crowd in a manner that was really dangerous. Mr. Kerry did not feel exactly happy at the whole proceeding, and began heartily to wish himself outside. Suddenly, thc savage gave a more frantic scream than before and seized a morsel(小块) of raw beef which a keeper extended to him on a long fork. This he tore to pieces eagerly, and devoured in the most voracious(贪婪的) manner, amid great clapping of hands and other evidence of satisfaction from the audience: 'I'll go now', thought Mr. Kerry, 'for who knows whether, in his hungry moods, he might not fancy finishing his dinner with me.' Just at this instant, some sounds struck his ear that surprised him. He listened more attentively and, to his amazement, found that amid the most fearful cries and wild yells, the savage was talking Irish. Now, Mr. Kerry had never heard of an African Irishman so he listened very closely, and, by degrees, not only thc words were known to him, but the very voice was familiar, so turning to the savage he addressed him in Irish, at the same time fixing him with a severe look.

'Who are you?' said Mr. Kerry.

'Billy McCabe, sir.'

'And what do you mean by playing your tricks here, instead of earning your living like an honest man?'

'Well,' said Billy, 'I'm earning the rent to pay you. One must do many strange things to pay the kind of rent you charge.'

1. Mr. Kerry was walking along the Strand because _____

A .he had nothing else to do.

B. he was late for an appointment.

C. he was looking for something to do.

D. he was reluctant to go home.

2. Inside the house, at first, Mr. Kerry____

A.    was nearly suffocated.

B.    could see nothing.

C. was pushed about.

D .couldn't hear anything

3. The wild man gave the impression of being dangerous by_______

A.    the way he moved    B.      the way he dressed

C.    the looks he gave     D.     the cries he made

4.    Mr Kerry decided to leave the house because _______

A.    he felt extremely frightened         B.     he was worried what might happen

C.    he didn’t wish to eat with the savage  D.    he feared he might have a heart attack

5. The wild man surprised Mr Kerry by speaking Irish since____

A. he was on show in London       B. he was a primitive savage.

C. he previously spoke nonsense     D. he was thought to be African.

儿童孤独症是______的一种类型，起病于______，主要表现为不同程度的______、______、______和行为方式刻板。

有三朵红头花和两朵蓝头花。将五朵花中的三朵花分别戴在A、B、C三个女孩的头上。这三个女孩中，每个人都只能看见其他两个女孩子头上所戴的头花，但看不见自己头上的花朵，并且也不知道剩余的两朵头花的颜色。

问A：“你戴的是什么颜色的头花？”

A说：“不知道。”

问B：“你戴的是什么颜色的头花？”

B想过一会之后，也说：“不知道。”

最后问C，C回答说：“我知道我戴的头花是什么颜色了。”

当然，C是在听了A、B的回答之后而作出推断的。试问：C戴的是什么颜色的头花？

对于采用近后备原则进行双重化配置的保护装置，每套保护装置应由不同的电源供电，并分别设有专用的直流熔断器或自动开关。