急性胰腺炎时尿淀粉酶升高时间是（）
A.病后即刻
B.病后4小时
C.血清淀粉酶升高2小时
D.血清淀粉酶升高的同时
E.与血清淀粉酶平行
参考答案：C
Every possible means _______ been taken to prevent the river _________.
A．have; polluting
B．has; polluted
C．has; from being polluted
D．have; being polluted
浮标法测流属于（）法。
