[名词解释] 梗死

室壁瘤 下列哪一项在突触前末梢释放递质中的作用最关键() ["A．动作电位到达神经末梢","B．神经末梢去极化","C．神经末梢处的Na内流","D．神经末梢处的K外流","E．神经末梢处的Ca内流"] 肉瘤 一期愈合 胃食管反流的主要症状为（） ["A．便秘","B．恶心","C．呕吐","D．腹痛","E．腹泻"] 梗死