测定缓、控释制剂释放度时，至少应测定几个取样点（）
A.1个
B.2个
C.3个
D.4个
E.5个
参考答案：C
Modern forms of transportation and communication have done much to ______ the isolation（隔离）of life in Alaska.
A．break down
B．break out
C．break into
D．break through
以天然矿物入药的药材是
A．雄黄
B．芒硝
C．滑石
D．
