问题 单项选择题 B型题

与肥大细胞相似,可释放组胺等活性物质参与超敏反应的是()。

A.中性粒细胞

B.淋巴细胞

C.单核细胞

D.嗜酸性粒细胞

E.嗜碱性粒细胞

答案

参考答案:E

解析:1.嗜碱性粒细胞胞质中含有大小不等的嗜碱性颗粒,这些颗粒中含有丰富的组胺、肝素等活性物质,可参与超敏反应。2.嗜酸性粒细胞有微弱的吞噬作用,但基本上无杀菌能力,它的主要作用是抑制嗜碱性粒细胞和肥大细胞合成与释放其活性物质,吞噬其释出颗粒,并分泌组胺酶来破坏组胺,从而起到限制超敏反应的作用。

阅读理解

Something roared like thunder. The earth shook a little and we heard the rat-a-tat-tat of gunfire. ‘‘Father!” Hassan cried. We sprung to our feet and raced out of the living room.

“Father! What’s that sound?” Hassan screamed, his hands outstretched toward Ali. Ali wrapped his arms around us. A white light flashed and lit the sky in silver. It flashed again and was followed by rapid sharp sounds of gunfire.

“They’re hunting ducks, ” Ali said in a hoarse voice. “They hunt ducks at night, you know. Don't be afraid.”

A siren(汽笛)went off in the distance. Somewhere glass broke and someone shouted. I heard people on the street, woken up from sleep. Hassan was crying. Ali pulled him close and held him with tenderness.

We stayed huddled (蜷缩)that way until the early hours of the morning. The shootings and explosions had lasted less than an hour, but they had frightened us badly, because none of us had ever heard gunshots in the streets. They were foreign sounds to us then. The generations of Afghan children whose ears would know nothing but the sounds of the bombs and gunfire were not yet born. Huddled together in the dining room and waiting for the sun to rise, none of us had any idea that a way of life had ended. The end came when Russian tanks were rolling into the very same streets where Hassan and I played, bringing the death of the Afghanistan I knew and marking the start of a still ongoing era of bloodletting.

Just before the sunrise, Baba’s car pulled into the driveway. His door slammed shut and his running footsteps pounded the stairs. Then he appeared in the doorway and I saw something on his face. Something I didn’t recognize right away because I’d never seen it before: fear. “Amir! Hassan!” He cried as he ran to us, opening his arms wide. “They blocked all the roads and the telephone didn’t work. I was so worried!”

We let him wrap us in his arms and, for a brief moment, I was glad about whatever had happened that night.

小题1:Who is the author of this passage?

A.Amir.

B.Ali.

C.Baba.

D.Hassan.小题2:By saying “They’re hunting ducks”, Ali _______.

A.told the children the truth

B.played a joke on the children

C.tried to calm the children

D.cheered the children up小题3:We can infer from the passage that  _______.

A.there were thunderstorms that night

B.Afghan children were used to the war

C.people on the street shouted and broke the windows

D.that night was the end of people's peaceful life小题4:From the last sentence of the passage, we know _______.

A.Baba's arms gave the author temporary comfort and joy

B.there was a chance that a world in peace was to come

C.what happened that night seemed nothing to the author

D.the author was glad to see his father come home safe

问答题 简答题