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问题 单项选择题


二、单项选择题

按分子极性大小进行分离可选用 ( )

A．硅胶
B．聚酰胺
C．离子交换
D．大孔吸附树脂
E．葡聚糖凝胶

答案

参考答案：A

解析：[知识点] 根据物质的吸附性差别进行中药有效成分的分离

改错题

下列各句均有错，请你找出后，在题前括号内填入选项并在横线上改正。

( ) 1. We like sitting under the tree and talk to each other.   ________

                   A      B                                C             D

( ) 2. Millie, is this yours book? Yes, it is.                          ________ 

                     A           B               C    D

( ) 3. What do you go to school every day? By bus.            ________

               A    B                C                            D

( ) 4. We don't have a art lesson today?                             ________

                    A      B   C         D

( ) 5. How many balls are they behind the door?                 ________

                       A      B          C       D

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单项选择题 A1/A2型题

肉眼血尿为1000mL尿中血的毫升数为（）。

A.0mL

B.1mL

C.3mL

D.4mL

E.5mL
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