有的债券流动性很好，基金管理人可以连续少量买入以“制造”出较高的价格，从而提高基金的业绩。 ( )
参考答案：错
His disappearance(失踪)______ by the police.
A．looked at
B．will be looked in
C．is being looked into
D．has been looked up
腰椎穿刺术的适应证有（）
A.后颅窝肿瘤
B.穿刺部位有感染或脊椎结核
C.蛛网膜下隙出血
D.颅内压增高伴有眼底视盘水肿
E.严重的血小板减少或未纠正的出血性疾病
