Objective:A new method was established to analyze and evaluate the progress of asthma based on the biological signal acquisition and processing system

which was used to observe the anti-asthmatic effects of Maxing Shigan decoction. Method: The biological signal acquisition and processing system was used to record the difference of breath wave before and after asthma induced by histamine phosphate

asthmatic latency and duration was recorded by the routine method at the same time

amplitude variations between the first or the last convulsive wave and the normal breath wave were determined according to the result observed by naked eye

then the diagnostic standard of asthmatic latency and duration were established preliminaryly. Breath wave of Guinea pigs was recorded 30 minute at the same way after Maxing Shigan decoction was gived for 5 days

influences of Maxing Shigan decoction in the asthmatic latency and duration were analyzed based on the above standard. Result: The average amplitude variation between the first or the last convulsive wave and the normal breath wave was 2 465% or 159%

Maxing Shigan decoction could delay the asthmatic latency and reduce the asthmatic duration

that showed that it had obvious anti-asthmatic effects. Conclusion: The anti-asthmatic effects of drugs can be observed objectively and standardly by the biological signal acquisition and processing system.