鸡血藤的性状特征() A.扁圆柱形 B.表面光滑 C.质坚硬 D.断面皮部有树脂状分

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问题:

鸡血藤的性状特征()

A.扁圆柱形

B.表面光滑

C.质坚硬

D.断面皮部有树脂状分泌物,可见3~8个偏心性半圆环纹

E.髓部偏向一侧

考点:中药学(医学高级)中药鉴定学中药鉴定学题库
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若|a|=4,|b|=2,且|a+b|=a+b,那么a-b的值只能是(  )

A.2

B.-2

C.6

D.2或6

题型:多项选择题

黄体功能不足的表现是 ()

A.月经周期缩短,月经频发,经前诊刮子宫内膜为分泌反应不良

B.月经周期缩短,月经频发,经前诊刮子宫内膜呈增生期变化

C.月经周期正常,经期延长,月经第5天诊刮子宫内膜呈混合型变化

D.月经周期正常,经期延长,月经第5天子宫内膜呈蜕膜样改变

E.月经周期正常,经血量,经前诊刮子宫内膜呈分泌型变化

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阅读理解

     Going to outer space is a little like going camping.You have to carry with you all the food and

equipment you need for your trip, so your food can't be too heavy or hard to prepare.Plus, there are

no refrigerators to keep food cold and fresh.

     Food with all the water dried out is lightweight and doesn't spoil.So, many space foods are dried

on Earth and stored in special packets.Some, such as dried pears, taste good right out of the packet.

But to eat the turkey in this outerspace Thanksgiving dinner, an astronaut must add water and heat the

packets.

     On Earth, gravity is the force that keeps your feet on the ground and your sandwich on your plate.

But there's no gravity in space.To keep food from floating away, astronauts on the Space Shuttle attach

the packets to a special tray.The tray can be fixed to a wall or to the astronaut's lap.To prepare their

food, astronauts use liquid forms of salt and pepper.The liquid sticks to the food better.Regular salt

and pepper would float away, maybe up an astronaut's nose.Achoo!

     Liquids float right out of cups and glasses, though.So astronauts drink everything from a small bag

with a straw(饮料吸管) that can be closed.Astronauts say that most space foods taste pretty good.

Some, such as apples and pudding are the same as the foods you eat on Earth.

      Astronauts eat tortillas(玉米粉圆饼) instead of bread because they make fewer crumbs(碎屑).

Floating crumbs could get stuck in equipment or an astronaut's eye.

     Your body uses food in space the same way it does on Earth.Your body must get rid of waste in

space too.

     During take off and landing, astronauts can't leave their seats to go to the bathroom.They wear

diapers(尿布) under their spacesuits instead.

     The Space Shuttle has a bathroom the size of a small closet.The toilet has bars that keep astronauts

from floating away.

      A strong flow of air is used instead of water to flush waste down the toilet.Back on Earth it's flushed

away-or sometimes studied by scientists.

1. Why do astronauts use liquid forms of salt and pepper to prepare food?

A. Liquid doesn't spoil.

B. Liquid is convenient to use in space.

C. Liquid is lightweight.

D. Astronauts are in great need of water.

2. What do astronauts think of space foods?

A. Most of them taste pleasant.

B. They are mostly fruits.

C. Most of them are cold.

D. They contain little meat.

3. Why don't astronauts eat bread?

A. Bread tastes bad.

B. Tiny pieces may float.

C. Bread weights heavy.

D. Bread is rather hard to prepare.

4. We can infer from the passage that astronauts ______.

A. drink from cups and glasses

B. always wear diapers in space

C. can move freely during landing

D. must pay attention to the crumbs in space

题型:多项选择题

论述发电机进相运行能力受哪些因素限制?

题型:多项选择题

属于钠通道阻滞药的抗心律失常药物是

A.普萘洛尔

B.维拉帕米

C.胺碘酮

D.普罗帕酮

E.异丙肾上腺素

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