遗传标记
参考答案：
用于研究基因遗传变异规律的可识别的等位基因
The company has been _______ of President(总裁) Smith for 20 years and who will _______ it after his retirement?
A．in the control; take over
B．in the control; take down
C．in control; take over
D．in control; take down
蛛网膜下腔麻醉期间的不良反应和并发症主要有哪些？
