[名词解释] 灰铸铁

分泌胸腺激素的中枢免疫器官是（） ["脾脏","骨髓","胸腺","卵黄囊","淋巴结"] 相 输尿管结石最多见的部位是（） ["肾盂输尿管连接处","输尿管跨过髂血管处","输尿管上1\/3段","输尿管中1\/3段","输尿管下1\/3段"] 取其缓和刺激（）。 ["外用药粉以菊花汁调之","外用药粉以米醋调之","外用药粉以水调之","外用药粉以油调之","外用药粉以鸡蛋清调之"] 常用于纠正胎位的腧穴是（） ["隐白","至阴","合谷","少泽","申脉"] 灰铸铁