例 1　女 ,5岁 ,因四肢无力 3年半就诊。足月顺产 ,12个月内各项发育均正常 ,18个月时可扶物站立、行走 ,但不能独立行走 ,以后其父母发现患儿逐渐四肢软 ,力弱 ,出现站立困难 ,双上肢抬举费力 ,双手持物困难 ,症状呈进行性加重 ,2岁时不能站立 ,以后病情稳定 ,肢体无力症状加 Example 1 Female, 5 years old, due to weakness 3 and a half years treatment. Full-term spontaneous delivery, all development within 12 months were normal, 18 months can be help to stand, walking, but can not walk independently, after their parents found that children gradually limbs soft, weak, standing difficulties, upper extremity lift Laborious, holding hands difficult, symptoms were progressive increase, 2 years old can not stand, after a stable condition, limb weakness plus