关于月经史的描述为XQ/Y―Z,其中X.Q分别代表什么() ["月经周期和经期天数","初潮年龄和月经周期","经期天数和末次月经日期","初潮年龄和经期天数"]
患者的感受阈值下降,对轻微的声音也感到难以忍受,称为()。 ["感觉过敏","知觉障碍","内感性不适","感知综合障碍"]
高电平调制在()放大器中进行。 ["小信号调谐","大信号调谐","高频功率"]
更换三乙基铝钢瓶必须在()中进行。 ["空气","水","氧气","完全氮封"]
谵妄状态最常见的幻觉是()。 ["听幻觉","内脏幻觉","视幻觉","味幻觉"]
天然气按照烃类组份可分为哪几类?