中文摘要：

目的设计一种大鼠下肢神经及肌肉功能测定系统，以实现对单组肌肉力量变化的无创动态观测，并评估该系统在生理及病理状态下的应用价值。方法测定系统由固定装置、传动装置、张力换能器、电刺激仪、生物信号采集系统及计算机等组成；评估SD雄性大鼠下肢肌肉收缩强度与电刺激脉冲宽度（0．1、0．2、0．3、0．4、0．5、0．6、0．7ms）／脉冲强度（8、12、16、20、24、28、32、36、40V）的量效关系；评估A型肉毒毒素腓肠肌麻痹模型（保妥适，1U／0．1m1）及对照组（0．1ml生理盐水）腓肠肌收缩强度的动态变化。结果腓肠肌收缩强度随脉冲强度（0-28V）或脉冲宽度（0-0．4ms）的递增呈增强趋势；当脉冲强度超过28V或脉冲宽度达到0．4ms以上，腓肠肌收缩强度曲线呈平台样改变[达最大值（28．2±2，1）g]；注射肉毒毒素后靶肌肉收缩强度于第7天降至最低水平[（1．87±0．66）g]，然后开始缓慢恢复，第3、7、14、30、45、60、75天均小于对照组，差异有统计学意义（P〈0．05）。结论大鼠下肢神经肌肉功能测定系统可以实现对单组肌肉功能的无创量化评估，能够有效反映肉毒毒素生物学效应的动态演变规律。

英文摘要：

Objective To dynamically observe the changes of muscle strength non-iuvasively, we design a novel rat lower limbs＇ nerve and muscle function measuring system. The application of the system was also evaluated under physiological and pathological conditions. Methods The system was composed of fixing device, actuating device, tension transducer, electrical stimulator, biological signal acquisition sys- tem and computer. Not only the dose-effect relationship of the pulse duration （0. 1,0. 2, 0. 3, 0. 4, 0. 5, 0. 6, 0. 7 ms） a~d pulse strength （8, 12, 16, 20, 24, 28, 32, 36, 40 V） on muscle strength, but also the dynamic change of muscle strength in both botulinum toxin-A group and control group were tested. Re- suits There waa an increase in muscle strength with increased pulse strength （ under 28 V） or with in- creased pulse duration （ under 0.4 ms）. When stimulation with a pulse strength above 28 V or a pulse du- ration above 0. 4 ms, a plateau phase would be detected [ （ 28.2 ± 2. 1 ） g ]. After injection of botulinum toxin, the strength of target muscle was decreased to the lowest level [ （ 1.87± 0. 66 ） g ] at day 7, followed by a recovery of muscle strength, but still lower than control group （P 〈 0. 05）. Conclusion The rat lower limbs＇ nerve and muscle function measuring system can evaluate muscle function non-invasively and quantitatively, and can effectively reflect the dynamic evolution of botulinum toxin biological effect.