题型:判断题 输尿管结石发生腰部绞痛的机制是()A.结石压迫输尿管壁,引起输尿管壁坏死B.结石合并上尿路感染C.结石嵌顿引起输尿管黏膜充血水肿D.结石在输尿管内移动或嵌顿引起输尿管平滑肌痉挛E.以上都不是 查看答案
题型:判断题 People cut down too many trees, _____ the greenhouse effect becomes more and more serious.A.soB.becauseC.althoughD.if 查看答案
题型:判断题 说明病毒已发生了变异的指标是( )A.HBsAg(+)HBeAg(-)HBV-DNA(-)B.HBsAg(+)HBeAg(+)HBV-DNA(+)C.HBsAg(-)抗HBs(+)抗HBe(+)D.HBsAg(+)HBeAg(-)抗-HBc(+)E.HBsAg(+)HBeAg(-)HBV-DNA(+) 查看答案