Airway mucus hypersecretion exhibits distinct circadian rhythmic characteristics， and its occurrence and progression are temporally associated with the accumulation of phlegm-rheum during the night and the tendency for symptoms to emerge or worsen in the early morning. These characteristics are consistent with the decline of neuroendocrine activity and abnormalities in core circadian clock rhythms described in modern chronobiology. Based on this understanding， time-based intervention is applied in addition to conventional syndrome differentiation. During the period from shen （申） hour to hai （亥） hour （approximately 15：00-23：00）， phlegm-resolving and panting-relieving Chinese herbal medicinals can be administered in advance to reduce excessive phlegm accumulation during the night.Furthermore， a combined "time-pattern-medicine" therapeutic strategy is proposed. For attacks occurring mainly in the morning， treatment focuses on diffusing lung and resolving phlegm. For symptoms aggravated at night， emphasis is placed on clearing heat and resolving phlegm， and for episodes occurring after midnight， treatment should additionally consider both tonifying the kidney and promoting qi reception. In addition to pharmacological intervention， therapies that follow annual and daily rhythms， including winter disease treated in summer， and midnight-midday acupuncture， may also be incorporated to promote circadian rhythm coordination and maintain homeostasis of the body's biological clock.

Objective: To construct severe acute respiratory syndrome (SARS)coronavirus 3CL protease gene into transforming vector prepare recombinant baculovirus and transduct it into infect insect cells to express SARS-3CL protease. Mothods: The 3cl-Teasy and pFastBac HTb bacmida were amplified. The 3cl gene was cloned into baculovirus transforming vector pFastBac HTb by enzyme-digest- and-ligase method,which was named recombinant pFB HTb-3cl. The pFB HTB-3cl was transformed into E.coli DH10Bac competent cells.The positive colonies were screened by three antibiotics and blue-white patch method. The bacmid-HTb-3cl recombinant baculovirus bacmid was obtained and purified to transfect St9 insect cells.The protease expressed in Sf9 insect cells were identified by SDS-PAGE. Results: Recombinant expression vector was obtained successfully. The 3CL protease expressed in insect cells were identified by SDS-PAGE. Conclusion: The expression of 3CL protease in insect cells provided foundation for detecting protein activities and screening inhibitor against SARS-3CL protease.