第32题: [单项选择]具有过敏毒素作用的补体成分是 A. C1q B. C2a C. C3a D. C8 E. C9 参考答案:C 答案解析:[解析] C3a和C5a被称为过敏毒素,可与肥大细胞或嗜碱性粒细胞表面C3a R和C3Ar结合,触发靶细胞脱颗粒,释放组胺和其他血管介质,介导局部炎症反应。
第33题: [单项选择]
What are they talking about A. Weekend plan. B. Changes in the city. C. Going camping in the summer. D. Life in the summer. 参考答案:C 答案解析:[听力原文]
M: I enjoy camping out in the summer. A great change from city life, I think.
W: Yes, you s