沙土灭火时,在距接触网()m以上时,可不停电。 ["2","4","5","10"]
男性,30岁,不慎被车撞伤至骨盆骨折,不能排尿,留置尿管顺利,但无尿液引出,自尿管注入生理盐水200ml,只回吸出100ml。治疗方法哪项错误。() ["补液","手术修补","切开引流盆腔血肿","抗生素治疗","持续引流膀胱"]
什么叫测量误差?
()主要用于制造低速,手动工具及常温下使用的工具、模具、量具。 ["硬质合金","高速钢","合金工具钢","碳素工具钢"]
可兴奋细胞兴奋时,共有的特征是产生() ["收缩反应","分泌","神经冲动","反射活动","动作电位"]
郑板桥