两个正数a，b的等差中项是92，等比中项是25，且a＞b，则双曲线x2a2-y2

开关浪涌

与CDK4和CDK6的抑制密切相关的CKIs是（）

A.cdc2

B.p53

C.p21

D.p16

E.cyclinD

对急性脑梗死患者，下列哪种情况不适于溶栓治疗：（）

A.发病6小时以内

B.CT证实无出血灶

C.病人无出血素质

D.出凝血时间正常

E.头部CT出现低密度灶

用氨气代替压缩空气进行气密性检验，可以提高试验的灵敏度。( )

Network managers have long (140) practical voice-over-IP (VOIP) solutions. VOIP (141) ease network management and decreases costs by converging a company’s telephony and data infrastructures into one network. And a VOIP solution implemented at a company’s head-quarters with far-reaching branch offices can (142) tremendous amounts of (143) in long distance phone bills, provided that solution delivers POTS-like voice (144) over the Internet.

（142）是（）

A.get

B.put

C.save

D.waste