题干

据调查,患有流感的人在讲话、咳嗽、打喷嚏时,会从鼻咽部喷出大量的含有流感病毒的飞沫悬浮于空气中,而周围抵抗能力不强的人吸入了这种带有病毒的空气以后,病毒进入呼吸道,就可能引起流行感冒。据此材料回答下列问题:

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同类题1

阅读理解。阅读下列四篇短文,从每小题后所给的A、B、C、D四个选项中,选出最佳选项。

    The Colonel(上校) asked Ashenden a good many questions and then suggested that he had particular qualifications for the Secret Service. Ashenden knew several European languages and the fact that he was a writer provided excellent cover: on the pretext(借口) that he was writing a book he could, without attracting attention, visit any neutral country.

    It was while they were discussing this point that the Colonel said, "You know you might get material that would be very useful to you in your work. I'll tell you an incident that occurred only recently. Very dramatic. A foreign government minister went down to a Mediterranean resort to recover from a cold and he had some very important documents with him that he kept in a dispatch case(公文箱). A day or two after he arrived, he picked up a beautiful blonde at some restaurant or other, and he got very friendly with her . He took her back to his hotel, and when he came to himself in the morning, the lady and the dispatch-case had disappeared. They had one or two drinks up in his room and his theory is that when his back was turned the woman slipped a drug in his glass.

    "Do you mean to say that happened the other day?" said Ashenden.

    "The week before last ."

    "Impossible," cried Ashenden. "Why! We've been putting that incident on the stage for sixty years, we've written it in a thousand novels. Do you mean to say that life has only just caught up with us?"

    "Well, I can guarantee the truth of the story." said the Colonel, "And believe me, the government has been put to no end of trouble by the loss of the documents."

    "Well sir, if you can't do better than that in the Secret Service," sighed Ashenden, " I'm afraid that as a source of inspiration to the writer of fiction, it's washout(失败)."

同类题2

研究人员用同种小鼠进行了某项实验,实验设计和结果如表所示,请据表分析回答:

组别

除每天喂养相同的饲料外,进行如下处理

在第11天测量并计算每组小鼠肝脏脂肪的平均含量(mmol•L1

连续11天每天喂下列试剂

同时第8天至第11天每天腹腔注射下列物质

甲组

等体积生理盐水

等体积生理盐水

0.49

乙组

等体积生理盐水

0.025mmol四环素

6.51

丙组

中药制剂(0.05g)

0.025mmol四环素

4.74

丁组

中药制剂(0.10g)

0.025mmol四环素

4.52

戊组

中药制剂(0.15g)

0.025mmol四环素

4.10

(1)若要观察小鼠皮下脂肪细胞中的脂肪颗粒,可用____ 染液染色后加以判断.

(2)请拟定实验题目____ 

(3)现有健康的体重相近、发育状况相同的雌雄小鼠各100只,按上表的实验设计,应如何对这些小鼠进行分组?____ .表中所示的实验,自变量有____ .

(4)甲组和乙组对照可说明____ .上表实验结果可初步说明该中药制剂能对小鼠起什么作用?____ .

(5)研究人员认为,还需要观察中药制剂单独使用时对小鼠肝脏脂肪含量的影响.请完善实验步骤:

①步骤一:按上表所示的实验设计的要求增加3组小鼠,并编号.

②步骤二:这3组小鼠除每天喂养相同的饲料外,还需分别喂0.05g、0.10g、0.15g的中药制剂共11天.同时在第8至11天注射____ ,并保持其它条件适宜且相同.

③步骤三:测量并统计实验结果,将得到的实验结果与上表的____ 组的结果进行对照,然后得出结论.