正常成人每天至少必须排出多少尿液才能清除体内的代谢废物？（）A.800ml B.10

用can, can't, do, don't, doesn't, does完成句子。

1. —_______ he play soccer well? —Yes, he can.

2. I _______ play the guitar, but I can't play it well.

3. —_______ your mother want to join the basketball club? —No, she doesn't.

4.The girl _______ like chess, but she likes volleyball.

5. —_______ they have basketballs?—No, they don't.

cDNA；antisenseRNA

3岁幼儿用动作跟随节奏的能力一般会经历哪几个阶段？

ISIC means( )Standard Industrial Classification．

A．Internate

B．Insurrection

C．International

D．Internal

患者，女，16岁，因胸闷、心悸就诊。2周前患上呼吸道感染。体检：P100/min，律不齐，心杂音(-)，两肺(-)。血象：WBC 11.0×10⁹/L，N0.8，胸部X线正常。 EKG’-QRS-T波群前出现P，波，P’波在Ⅱ、ⅢaVF倒置，aVR、aVL直立，P’-R间期0.08s，QRS波群正常，有完全性代偿性间歇。心电图诊断最可能为

A．房性期前收缩
B．室性期前收缩
C．窦性心律不齐
D．交界区性期前收缩
E．间歇性预激