醛固酮的作用是
A．保钾排钠
B．调节钙磷代谢
C．调节酸碱平衡
D．保钠排钾
E．以上均不对
参考答案：D
There is a wooden bridge ______the river _______ my house.
A．above, in front of
B．over, in the front of
C．above, in the front of
D．over, in front of
近视眼表现为
A．视近不清B．视远不清C．圆锥角膜D．眼位易发生内斜E．无立体视觉
