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问题 单项选择题

与醋硝香豆素同用可降低其抗凝作用的药物是

A．阿司匹林

B．苯妥英钠

C．四环素

D．氯贝丁酯

E．氯霉素

答案

参考答案：B

解析：苯妥英钠为肝药酶诱导剂，能加速醋硝香豆素代谢从而降低其抗凝作用。

问答题

下列是木炭在氧气里燃烧的实验作图试回答下列问题：

（1）指出图中a、b仪器的名称，a是______，b是______．

（2）C图中，木炭在氧气中燃烧时发生的现象是______和______，燃烧停止后，取出坩埚钳，往集气瓶里加少量澄清石灰水，振荡．发生的现象是______

（3）B图中，用坩埚钳夹取一小块木炭在火焰的______部分迅速烧红．C图中盛装的氧气瓶口盖上玻璃片的目的是______

（4）写出C、D表示的操作中发生的化学反应方程式．C图中______．D图中______．
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单项选择题

(二)

Artificial flowers are used for scientific as well as for decorative purposes. They are made from a variety of materials, such as wax and glass, so skillfully that they can scarcely be distinguished from natural flowers. In making such models, painstaking and artistry are called for, as well as thorough knowledge of plant structure. The collection of glass flowers in the Botanical Museum of Harvard University is the most famous in North America and is widely known throughout the scientific world. In all, there are several thousand models in colored glass, the work of two artist-naturalists, Leopold Blaschka and his son Rudolph.

The intention was to have the collection represent at least one member of each flower family native to the United States. Although it was never completed. It contains more than seven hundred species representing 164 families of flowering plants, a group of fruits showing the effect of fungus diseases, and thousands of flower parts and magnified details. Every detail of these is accurately reproduced in color and structure. The models are kept in locked cases as they are too valuable and fragile for classroom use.

Which of the following statements is true of the flowers at Harvard University（）

A．They form a completed collection.

B．They have a marvelous fragrance.

C．They are loaned to schools for classroom use.

D．They use authentic representations.
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