A novel HPLC-CAD method coupled with on-line solid phase extraction ( SPE ) for the determination of erythrocin which was widely used in livestock farming was developed. After mixed with diatomite, 5. 0 g manure sample was put into the cell and extracted with hot water at 70℃ and 10. 3 MPa. An on-line SPE methodology was applied to pre-treat the sample, and the sample was seperated on an Acclaim 120 C18 column and analyzed by corona CAD detector using acetonitrile and 0. 1% formic acid as mobile phase. Good linearity for erythrocin was obtained in the range of 21-2000 μg/kg. The detection limit was 6. 3 μg/kg. The average recoveries were 79. 2%-87. 5%.

12 cases of severe pulmonary infection were treated with ceftizoxime, one of cepha-losporins of the third generation. Clinical observation and pharmacokinetics were carried out. The result showed that intravenous infusion was the best route of drug administration. It had the advantages of high serum concentration and prolonged maintenance of serum level. 1 gram of ceftizoxi-me, two times a day, was enough for most pathogens except Pseudomonas aeruginosa.