栓子
稳态进动快速成像序列的稳态是指() ["A．横向和纵向磁化矢量均达到稳态","B．横向磁化矢量达到稳态","C．纵向磁化矢量达到稳态","D．图像的对比达到稳态","E．图像的信噪比达到稳态"]
柏油便中的血多来源于() ["A．胃及十二指肠","B．结肠","C．肛门直肠","D．空肠","E．回肠"]
婴儿腹泻导致代谢性酸中毒的主要原因是() ["A．饥饿","B．机体酸性代谢产物产生增多","C．排泄酸性代谢产物减少","D．腹泻液中丢失HCO","E．以上都不是"]
主肺动脉窗层面不包括哪一解剖结构() ["A．升主动脉和降主动脉","B．降主动脉，气管","C．上腔静脉","D．奇静脉弓通常也位于此层面","E．头臂静脉"]
不完全再生
