减压阀的作用有哪些?
腰麻穿刺进入蛛网膜下隙的部位俗称() ["脊髓","终池","马尾","腰膨大","脊髓后根"]
应与女性膀胱憩室鉴别的病变是() ["卵巢囊肿","卵巢肿瘤","异位妊娠","盆腔炎症","盆腔肿瘤"]
硬膜外阻滞完善的时间需() ["3~5min","8~10min","12~20min","25~30min","40min以上"]
鉴别胆囊癌实块型与胆囊内胆泥或血块最有价值的指标是() ["实性结构回声的大小","实性结构的形态及回声强弱","胆囊腔消失的程度","是否含有结石","团块内检出高速动脉血流信号"]
隔膜阀结构特点有哪些?