患者女，29岁。反复咳嗽、咳痰10年，咯血2天，每天咯血量约300ml。查体：右下肺湿性啰音，胸片示右下肺纹理增重紊乱。

属于DPB临床诊断标准中的内容是（）（提示：HRCT检查发现患者双下肺多发小结节影，拟诊弥漫性泛细支气管炎（DPB）。）

A.鼻窦炎

B.嗜异凝集试验阳性

C.冷凝集试验阳性

D.肺功能检查示阻塞性通气功能障碍

E.过敏原皮试阳性

F.血曲菌抗原阳性

G.痰培养为铜绿假单胞菌

An analog signal’s characteristic quantity representing data may (66) . at any instant, any value within a continuous (67) . For example, an analog signal may follow continuously the values of another physical quantity representing data.

A discrete signal is composed of (68) elements in time, each element having one or more characteristic quantities which can represent data. Examples of characteristic quantities are amplitude, waveform, (69) , and position in time. A digital signal is a special case of discrete signals, in which data are represented by a (70) number of well-defined discrete values that one of its characteristic quantities may take in time.

（70）处填（）。

A．limited

B．finite

C．restricted

D．bounded