狗的胰岛被切除后，发现狗的尿液中含有葡萄糖，这说明胰岛与降低血糖浓度有关。[ ]
√
体外循环麻醉时，监测病人全血激活凝固时间(ACT)病人生理值多少秒，体外循环转前应为多少秒
A．＜130，＞480 B．＜200，＞300 C．＜15，＞100 D．＜300，＞800 E．＜45，＞240
Students _____ remain in their seats until all the papers have been collected.[ ]
A. may
B. shall
C. need
D. can
