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问题 填空题

下图是培育表达人乳铁蛋白的乳腺生物反应器的技术路线。图中tetR表示四环素抗性基因，ampR表示氨苄青霉素抗性基因，BamHⅠ、HindⅢ、SmaⅠ直线所示为三种限制酶的酶切位点。 据图回答：

过程①可采用的操作方法是（）（填字母代号）。 A．农杆菌转化 B．大肠杆菌转化 C．显微注射 D．细胞融合

答案

参考答案：C

单项选择题 A3/A4型题

男性，56岁。患慢性骨髓炎8个月，血红蛋白70g／L，白细胞、血小板正常。血清铁6.21μmol／L，铁蛋白206μg/L，骨髓增生活跃，细胞外铁（+++）。

实验室检查符合该病特点的是（）

A.血清铁下降，总铁结合力上升

B.血清铁下降，转铁蛋白饱和度下降

C.贫血程度多为重度

D.多呈大细胞低色素贫血

E.骨髓外铁减少
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单项选择题

Aspirin is one of the safest and most effective drugs invented by man. The most popular medicine in the world today, it is an effective pain reliever. Its bad effects are relatively mild. It is also cheap.For millions of people suffering from arthritis, it is the only thing that works. Aspirin, in short, is truly the 20th-century wonder drug. It is also the second largest suicide drug and is the leading cause of poisoning among children. It has side effects that, although relatively mild, are largely unrecognized among users.Although aspirin was first sold by a German company in 1899, it has been around much longer than that. Hippocrates, in ancient Greece, understood the medical value of tree barks and leaves which today are known to contain a chemical found in aspirin. During the 19th century, there was a great deal of experimentation in Europe with this chemical, and it led to the introduction of aspirin. By 1915, aspirin tablets were available in the United States.A small quantity of aspirin relieves pain and inflammation. It also reduces fever by affecting some of the body’’s reactions. Aspirin is very irritating to the stomach lining. The best way is to chew the tablets before swallowing them with water, but few people can stand the bitter taste. Some people suggest crushing the tablets in milk or orange juice.

According to this passage, ________may NOT be the right way to take aspirin.

A．chewing the tablets

B．swallowing the tablets

C．crushing them in milk

D．putting them in dishes
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