问题 单项选择题

脉搏血氧饱和度仪的原理和使用,下述哪项不恰当()。

A.仪器包括光电感受器、微处理机和显示器三部分

B.基本原理是血红蛋白吸收光线的能力与其含氧浓度的相关性

C.如严重低氧,当氧饱和度低于70%时,其测定数据可能不准确

D.因肢体活动发生接触不良时也可能有误读

E.不论氧分压多高,SpO2均能反映PaO2的变化

答案

参考答案:E

阅读理解

Most rain forests lie close to the equator(赤道),where the climate is often mild and there are long hours of sunshine.The warmth of the land heats the air above,causing it to rise and tiny drops of water to fall as rain.The rainfall can reach at least 98 inches a year.This wet,warm world with plenty of sunlight is perfect for plants to grow,so the trees grow fast with green leaves all the year round.The trees themselves also have an effect on the climate.They gather water from the soil and pass it out into the air through their leaves.The wet air then forms clouds,which hang over the treetops like smoke.These clouds protect the forest from the daytime heat and night-time cold of nearby deserts,keeping temperatures fit for plant growth.

Rain forests slightly farther away from the equator remain just as warm,but they have a dry season of three months or more when little rain falls.Tree leaves fall during this dry season and new leaves grow when the wet season or monsoon(雨季) begins.Thus these areas are known as the “monsoon forest”.

Another type of rain forest grows on tropical mountains.It is often called the “cloud forest” because clouds often hang over the trees like fog.

The rain forest is the ideal place for the growth of many different trees.Most of them depend on animals to eat their fruits and spread their seeds.When the fruits are eaten,the seeds inside them go undamaged through animals’ stomachs and are passed out in their droppings.The seeds lying on the forest floor then grow into new trees.

小题1:The climate of the rain forests near the equator is _______.

A.mild,wet and windy

B.hot,rainy and foggy

C.hot,wet and cloudy

D.warm,wet and sunny小题2:We can learn from the passage that _______.

A.tree leaves are green all the time in the monsoon forest

B.there is a dry season in the cloud forest on tropical mountains

C.clouds help the plants in the rain forest near the deserts to grow

D.the formation of climate in the rain forest has little to do with the trees小题3:According to the passage,_______ play the most important role in the spreading of seeds.

A.animals

B.droppings

C.fruits

D.winds小题4:This passage is most likely to be found in _______.

A.a travel guide

B.a story book

C.a technical report

D.a geography book

名词解释