问题 问答题 简答题

简述分泌性中耳炎的发病机制。

答案

参考答案:

正常情况下咽鼓管通过其软骨段管腔的开闭调节中耳气压。咽鼓管功能不良时,外界空气不能进入中耳,中耳内原有的气体逐渐被粘膜吸收,腔内形成负压。引起中耳粘膜静脉扩张,淤血,毛细血管通透性增加,鼓室内出现漏出液。如负压不能得到解除,中耳粘膜可发生一系列病理变化,主要表现为上皮增厚,上皮细胞化生,鼓室前部低矮的假复层柱状上皮变为增厚的纤毛上皮,鼓室后部的扁平上皮变为假复层柱状上皮,杯状细胞增多,分泌增加,上皮下有病理性腺体样组织形成,固有层血管周围出现以淋巴细胞及浆细胞为主的圆形细胞浸润。疾病恢复期,腺体逐渐退化,分泌物减少,粘膜渐恢复正常。

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Have you ever had the strange feeling that you were being watched? You turned around and, sure enough, someone was looking right at you!

Parapsychologists (灵学家) say that humans have a natural ability to sense when someone is looking at them. To research whether such a “sixth sense” really exists, Robert Baker, a psychologist at the University of Kentucky, performed two experiments.

In the first one, Baker sat behind unknowing people in public places and stared at the backs of their heads for 5 to 15 minutes. The subjects were eating, drinking, reading, studying, watching TV, or working at a computer. Baker made sure that the people could not tell that he was sitting behind them during those periods. Later, when he questioned the subjects, almost all of them said they had no sense that someone was staring at them.

For the second experiment, Baker told the subjects that they would be stared at from time to time from behind a two way mirror in a laboratory setting. The people had to write down when they felt they were being stared at and when they weren’t. Baker found that the subjects were no better at telling when they were stared at and when they weren’t. and they were no better at telling when they were stared at than if they had just guessed.

Baker concludes that people do not have the ability to sense when they’re being stared at. If people doubt the outcome of his two experiments, said baker, “I suggest they repeat the experiments and see for themselves.”

小题1:The purpose of the two experiments is to                                 .

A.explain when people can have a sixth sense

B.show how people act while being watched in the lab

C.study whether humans can sense when they are stared at

D.prove why humans have a sixth sense小题2:In the first experiment, the subjects                             .

A.were not told that they would be stared at

B.lost their sense when they were stared at

C.were not sure when the would be stared at

D.were uncomfortable when they were stared at小题3:What can be learned from the passage?

A.People are born with a sixth sense.

B.The experiments support parapsychologists’ idea.

C.The subjects do not have a sixth sense in the experiments.

D.People have a sixth sense in public places.