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Results of the effective rates of 4 groups at 6 time points are shown. Effective rates of Group IV were always higher than 50%; effective rates of Group III were higher than 50% except 12 hours time point; in Group II, the effective rates were higher than 50% at 10 and 20 minutes, but lower than 50% at other time points; Group I never had effective rate higher than 50% at any time.
