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问题 选择题

茶多酚(Tea Polyphenols)是茶叶中多酚类物质的总称。茶多酚中的活性物质没食子儿茶素(EGC)具解毒和抗辐射作用，能有效地阻止放射性物质侵入骨髓，其结构如下图所示。

关于EGC的下列叙述中正确的是：                                    

A．分子中所有的原子共面

B．1 mol EGC与4 mol NaOH恰好完全反应

C．遇Fe发生显色反应

D．易发生氧化反应和取代反应，相对较难发生加成反应

答案

答案：D

题目分析：A．分子中存在—CH2—结构，键角为109°28′，故所有的原子不可能共面，说法错误；B．1 mol EGC含3mol的酚羟基，应与3 mol NaOH恰好完全反应，故不正确；C．酚遇Fe3+发生显色反应，说法不正确；D．酚类物质易发生氧化反应和取代反应，但苯环相对较难发生加成反应，说法正确。

完形填空

阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空，并将答案填写相应位置上。

The most influential book in my life

The Story of My Life by Helen Keller is the most influential book in my life. It __1__ (fill) with courage, struggle and faith throughout. Helen Keller was once in deep despair in her __2__ (child), but finally she decided to overcome her physical defects and live happily. Furthermore, she showed great patience, ___3___ (do) well in her long and hard learning period.

I have learned, above all, three lessons from her story. First, she taught me that often the road to success is to face hardships ___4____ (brave). Maybe you are born under an ill star yet you can stand a better chance ___5___ others. It is therefore important that you screw up your courage ____6____courage is needed. Second, the impairment of part of her senses did not prevent ___7___ from learning. On the contrary, she ___8___ (make) continual efforts to go deeper into the realm of knowledge her fortitude had thus helped her overcome many handicaps. ___9___, she advised that we should make the most of our sense-organs as if we ___10___ (lose) them soon because this way we would observe the world more carefully than ever before.
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多项选择题

患者男性，78岁，因“胸闷、憋气6个月余，加重伴咳黄痰4日”来诊。查体：血压130/80mmHg（1mmHg=0.133kPa），脉搏90次/分，双肺呼吸音粗，右下肺可闻及湿啰音，心率90次/分，律齐，未闻及杂音，双下肢轻度水肿。

应考虑的诊断是（）

A.冠心病心力衰竭

B.急性心肌梗死

C.肺源性心脏病

D.肺栓塞

E.慢性阻塞性肺疾病

F.支气管扩张

G.肺癌
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