与活动有关的疼痛和血尿，首先应考虑（）
A.泌尿系感染
B.泌尿系肿瘤
C.泌尿系畸形
D.泌尿系结石
E.泌尿系异物
参考答案：D
It makes little _____now to tell our children that their grandparents once boiled leather shoes to stop
their hunger on their way to the northeast . [ ]
A. idea
B. meaning
C. sense
D. use
波尔效应是指
A．p(CO2)与[H+]升高使Hb与O2亲和力下降B．p(CO2)与[H+]升高使Hb与O2亲和力增强C．O2与Hb结合将促使CO2释放D．O2与Hb结合将抑制CO2释放E．O2与Hb结合将促使CO2结合
