临床资料:1.先证者 男,47岁,工人。因渐起行走不稳,饮水呛咳,构单欠清5年就诊。患者5年前开始出现行走不稳,并缓慢进行性加重。3年前出现骑车左右摆动,上下楼梯困难.不能直线行走,易跌倒。1年前出现构音欠清,饮水呛咳。约半年前出现系钮扣、书写等精细动作困难。查体:智能正常,双足弓形足,软腭运动正常,构音欠清,咽反射迟钝,伸舌右偏,四肢肌力正常。肌张力偏低,腱反射(+)～(++),左侧巴氏证(+),双侧霍夫曼征(+),反击征(+),宽基步 Clinical data: 1. Proof of the male, 47 years old, workers. Due to the gradual walking instability, cough drinking water, structure list due 5 years treatment. The patient started to walk unsteadily 5 years ago and was slowly exacerbated. 3 years ago, riding around there, difficult to go up and down the stairs. Can not walk straight, easy to fall. A year ago, the articulation was not clear, drinking water and coughing. About six months ago appeared buttons, writing and other fine movements difficult. Physical examination: normal intelligence, bipedal foot-shaped, soft palate exercise is normal, due to poor articulation, pharyngeal reflex dull, right tongue extension, muscle strength normal. Muscle tension is low, tendon reflex (+) ~ (++), left Passar card (+), bilateral Huffman sign (+), counterattack sign