什么是丁基橡胶密封胶?
参考答案:以丁基橡胶为主要成份的非定形密封材料。
Living with a host family while studying abroad, in which there may be some other college students, __________ you the chance to learn more about the new culture.
A.give
B.gives
C.giving
D.to give
[复合型非选择题]中年男性患者,发热、黄疸。血清学检查HBsAg(+)、抗-HtBs(+)。
HBV感染,下列哪种成分用常规方法在血清中查不到()
A.HBsAg
B.抗-HBs
C.抗-HBe
D.HBeAg
E.HBcAg