问题 单项选择题 A1/A2型题

下列对中枢兴奋药的特征叙述不正确的是()

A.反复用药很难避免惊厥的发生

B.比人工呼吸机维持呼吸更加安全有效

C.作用时间短,需反复用药方可长时间维持呼吸

D.选择性不高,安全范围狭窄

E.主要用于中枢抑制中毒或某些传染病所致中枢性呼吸衰竭

答案

参考答案:B

解析:中枢兴奋药的特征:1、选择性不高,安全范围小;2、兴奋呼吸中枢的剂量与致惊厥剂量之间的距离小;3、对深度中枢抑制的患者,需要反复用药才能长时间维持患者呼吸,因而很难避免惊厥的发生,所以除严格掌握剂量外,这类药物的应用宜限于短时就能纠正的呼吸衰竭患者。临床主要采用人工呼吸机维持呼吸,因为人工呼吸机远比呼吸兴奋药有效而且安全可靠,所以答案为B。

阅读理解

In the early hours of March 8, a Boeing 777 took off from Kuala Lumpur, Malaysia. Its destination was Beijing. But for unknown reasons, it never arrived there.

There were 239 people on the Malaysia Airlines flight, including 154 Chinese. As of March 13, 12 different countries, including Malaysia, China, Vietnam and the US, were searching for the plane.

The disappearance is an “aviation (航空) mystery”, Azharuddin Abdul Rahman, the head of Malaysia’s Civil Aviation Authority, said on March 10.There was no clear sign of a crash by March 13.

Between 1-2 hours after takeoff, the plane suddenly lost contact with people on the ground. The weather was clear, and the pilots didn’t make any calls . No evidence was found in the area where the flight last made contact. People are also talking about a possible hijacking (劫机).

International police agency Interpol confirmed on March 9 that at least two passengers on the flight had used stolen passports to get on board. “We are looking at all possibilities,” said Malaysian Transport Minister Hishamuddin Hussein. The incident is now being called simply a “plane disappearance”.

So, what are some possible causes of a plane disappearance? An AP story provided a summary.

1. A failure of the plane’s body or its engines. However, even if both engines stopped working, the plane could still glide (滑翔) for up to 20 minutes, giving pilots time to make an emergency call.

2. Bad weather. Planes are designed to fly through most severe storms. However, in June 2009, an Air France flight from Rio de Janeiro to Paris crashed during a bad storm over the Atlantic Ocean.

3. A bomb. Throughout history, several planes have been brought down by bombs.

4. An accidental shoot-down by some country’s military. In July 1988, the US Navy accidentally shot down an Iran Air flight. In September 1983, a Korean Air Lines flight was shot down by a Russian fighter jet.

No matter how unlikely a situation, it’s too early to determine what really happened to MH370. It could take months, if not years, to rule out any possibilities, say experts..

小题1:How many cities are mentioned in this passage?

A.Four cities.

B.five cities.

C.Six cities.

D.Seven cities.小题2:What could the underlined phrase “rule out” in the last paragraph mean?

A.cross out

B.get rid of

C.take out

D.take the place of小题3:What could be the best title of the passage?

A.An Air Crash

B.The Causes of the Disappearance

C.The Disappearance of MH 370

D.An Aviation Mystery

判断题