颈动脉窦位于（）。 ["颈总动脉","颈总动脉分叉处","颈内动脉起始处","颈外动脉起始处","颈总动脉后方"] 关于普萘洛尔抗心律失常的机制，哪项错误（） ["阻断心肌β受体","降低窦房结的自律性","降低普肯耶纤维的自律性","治疗量就延长浦氏纤维的有效不应期","延长房室结的有效不应期"] 骨肉瘤的好发年龄是（） ["15岁以下","15～25岁","婴幼儿","25～40岁","40岁以上"] 宫颈糜烂是指（） ["宫颈上皮缺如","宫颈溃疡","宫颈先天发育不良","宫颈鳞状上皮脱落被柱状上皮覆盖","宫颈陈旧裂伤外翻"] 妊娠期间摄入过量可导致新生儿血钙过高的药物是（） ["氯霉素","庆大霉素","维生素D","四环素","甲巯咪唑"] 血清铁减低，总铁结合力增高及转铁蛋白饱和度减低见于（）。