背向散射系数的定义是:与入射声波成多大角度的方向上,单位体积和单位立体角的微分散射截面() ["A.90","B.180","C.60","D.45","E.各个方向"]
男性尖锐湿疣皮损多见于() ["A.龟头","B.冠状沟","C.包皮系带","D.腹股沟"]
彩色血流图是指() ["A.振幅调制型","B.辉度调制型","C.彩色血流显像","D.多普勒频谱显示","E.以上都不是"]
关于彩色多普勒血流显像下列哪项是错误的() ["A.血流朝向探头,显示红色","B.血流背向探头,显示蓝色","C.能量显示为混合色","D.出现紊流为混合色","E.血流速度高显示彩色亮度大"]
以下关于尖锐湿疣组织学特点描述错误的是() ["A.可见颗粒层和棘层上部空泡细胞","B.表皮乳头瘤样增生","C.表皮角化不全","D.真皮浅层毛细血管周围无炎症细胞浸润"]
获得性内斜视一般在________岁以后发生。