一个完善的提升信号系统，应当包括工作信号、（）、检修信号、安全、保护信号、通讯信号及

—What do you think of his speech?

—Oh, wonderful. But his voice sounded really ____ when he first started speaking.     [ ]

A. aloud  

B. worry  

C. nervous  

D. quiet

用多普勒频谱直接测量的血流数据是（）.

A.搏动指数

B.速度时间积分

C.阻力指数

D.舒张／收缩比

E.收缩期峰值速度

A real estate developer in Florida, desiring to protect his high-rise apartment building on the beach from hurricane damage, has planted sea oats in two rows in front of his building in order to encourage the development of sand dunes between the water and his building.
Which of the following, if true, casts the most doubt on the probable effectiveness of the developer’s plan ？（）

A. Sand dunes provide little protection for tall buildings against the wind, which is sufficiently powerful even in minor hurricanes to cause serious damage to buildings.

B. Sand dunes have been shown to provide effective protection against the storm surge, the pounding waves driven by hurricane-force winds onto dry land.

C. Although sea oats will lead to the growth of sand dunes over many years, it would be far faster to build concrete bunkers between the building and the water.

D. Hurricane insurance has become so expensive that many owners of beachfront property choose not to buy it.

E. The developer has invested in reinforced steel girders and shatterproof glass as a way of minimizing damage to his building in the event that a hurricane hits the area.

男，58岁，突然不能言语2h，无头痛呕吐。有高血压病史，未规则服药。体检：血压160/90mmHg，能按照医师的指令动作但不能说话，表现为运动性失语。脑神经正常，右上肢肌力4级，腱反射略活跃，巴宾斯基征阴性。

最可能受累区域的供血动脉是（）

A.大脑中动脉

B.大脑前动脉

C.大脑后动脉

D.椎动脉

E.基底动脉

胃癌早期症状是

A．上腹痛
B．贫血
C．腹块
D．进食梗阻感
E．消化不良，嗳气