【摘要】 应用平皿二倍稀释法对1987年临床分离的8种常见革兰氏阴性杆菌1098株比较了头孢三嗪与头孢哌酮的体外抗菌作用,并用11株标准酶产生菌与临床分离的产酶耐药菌制备β-内酰胺酶.对二药的酶稳定性与对产酶耐药菌的抗菌作用同时进行了比较.结果表明头孢三嗪对所测定的1098株阴性杆菌的抗菌作用比头孢哌酮强2—8倍,对某些β-内酰胺酶产生菌如TEM—2,SHV—1,K₁等产生菌及临床分离的产酶耐药克雷白肺炎杆菌、大肠杆菌等抗菌作用,头孢三嗪比头孢哌酮强32倍以上.酶稳定性研究结果证实头孢三嗪对所测定的7种β-内酰胺酶提取液均高度稳定,头孢哌酮对酶不稳定.更多还原

【Abstract】 A comparative studyon antibacterial activity of ceftriaxone andcefoperazone against 1098 isolates ofGram-negative rods from 8 genera iso-lated in 1987 was carried out. The resultsshowed that clinical pathogens tested ex-cept Ps. aeruginosa were highly susceptibleto ceftriaxone. The range of MIC50 andMTC90 of ceftriaxone against E. Coli(217) , K 1, Pneumoniae (174), Proteus sp(198) and Ent. cloacae (21), S. typhi (188),Shigella dysenteriae(32) and Ent. aerogenes(71) were <0.016-0.31 and 0.031-1mg / l,respectively. The corresponding range ofMIC50 and MIC90 of cefoperzone were0.031-1 and 0.062-8mg/ l, respectively.The in vitro activity of ceftriaxone againstGram-negative rods wad 2-8 timesstronger than of cefoperzone. Antibacterialactivity of ceftriaxone against standardbeta-lactamase producing strains whichproduce TEM-1, TEM-2, SHV-1,OXA-1, OXA-3, K1, PSE-1 and PSE-4enzymes was also much stronger than thatof cefoperazine. MICs of ceftriaxoneagainst TEM-1, TEM-2, SHV-1,OXA-1, OXA-3 enzyme producingstrains were lower than 0.016mg / l. MICof ceftriaxone against K 1 producing strainwas 4mg / l, while the corresponding MICsof cefoperazone against TEM-2 and K1enzyme producing strains were 0.5 and256mg / l respectively. It means that the invitro activity of ceftriaxone against someenzyme producing resistant organisms weremore than 32 times stronger than that of cefoperazone. The results of enzyme stabil-ity test showed that ceftriaxone was highlystable to beta-lactamases tested includingstandard beta-lactamases TEM-1,TEM-2, SHV-1, P99 and Ps. acruginosa5. The enzyme stability of ceftriazone wassimilar to that of cefotaxime. Usingcephaloridine as a control (hydrolysisrate = 100%), the relative hydrolysis rate of7 enzyme extracts against cefoperazonewas 17.6-89.6%. The present results con-firmed our previous research data thatcefoperazone was not stable to beta-lactamases.更多还原