问题
多项选择题
下列关于SC描述，正确的有（）。
A.IgA缺陷者可合成SC
B.介导分泌型IgA的转运
C.辅助分泌型IgA与特异性抗原结合
D.能抵抗蛋白酶对分泌型IgA的降解作用
E.由粘膜上皮细胞合成
答案
参考答案：A, B, D, E
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下列关于SC描述，正确的有（）。
A.IgA缺陷者可合成SC
B.介导分泌型IgA的转运
C.辅助分泌型IgA与特异性抗原结合
D.能抵抗蛋白酶对分泌型IgA的降解作用
E.由粘膜上皮细胞合成
参考答案：A, B, D, E
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| Mr. Turner works in a middle school. As a good 1 , he is friendly to his students. And he is always strict 2 himself. He often tells his students to do their best to 3 the persons 4 trouble. One Saturday morning, Mr. Turner went to see his friend who was ill in hospital. As something was wrong 5 his car, he had to take a bus. After he got on the bus, he found a seat and sat down. But soon 6 people got on the bus and some had to stand. He looked 7 and saw a woman behind. He stood up and gave his seat to her. The woman said 8 and sat down. Her behaviour(举止)made Mr. Turner 9 . "It's necessary for her to be taught how 10 polite," he said to himself. Then he asked, "What did you say, Madam?" "I didn't say anything," answered the woman. "I thought you said THANK YOU." When the woman heard this, her face turned red slowly. | ||||
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