This paper mainly introduces the principles of a type of circuit for measuring frequency & duty cycle of low-frequency signals, and its applications in neuron-threshold stimulator.

Lumbar plexus combined sciatic nerve block was performed with the help of a nerve stimulator and 0.

The stimulus threshold,maximal stimulus,peak value of compound action potential and refractory period were measured on the toad sciatic nerves after 30 seconds while adding ethanol or acetaldehyde of different concentration with Ringer solution.