白化病主要是上述哪种酶缺乏所致()苯丙酮酸尿症是患者体内缺乏上述哪种酶所致()A．苯

为进一步确诊首先应做的检查

A．诊断性腹腔穿刺

B．X线腹部立位片

C．急诊内镜

D．肝胆脾超声

E．心电图+心肌酶

用所给词的适当形式填空。

1. I'm going_____(sightsee) in Italy.

2. She plans_____(have)a very relaxed vacation.

3. What should they_____(take)with them?

4. My grandfather often goes_____(fish) every Sunday.

5. Can your sister_____(speak)English?

It has been widely accepted that only when the students take an active part in the class activities _______ the most effective.

A．teaching will be

B．will teaching be

C．has teaching been

D．teaching has been

以下哪一项不是急性病毒性肝炎的主要临床表现

A．食欲减退、恶心
B．乏力
C．肝肿大及肝功能损害
D．部分病例出现黄疸
E．消瘦

对用于测量30MHz以下的固定站址，在工作频率上，架空导线高出地面1米的情况下，使其相距站址至少半个波长。