用临床分离得到的577株革兰氏阳性球菌和革兰氏阴性杆菌测定新的半合成青霉素 Piperacillin 的体外活力。结果浓度在0.78μg/ml 时除对青霉素 G 耐药的金葡菌外,全部革兰氏阳性球菌均被抑制,浓度在25μg/ml 时其中的耐药菌株也被抑制。大部分的肠道菌对 Piperacillin 十分敏感, In vitro activity of the new semisynthetic penicillin Piperacillin was assayed using 577 strains of gram-positive cocci and gram-negative bacilli isolated clinically. Results All of the Gram-positive cocci were inhibited except for S.aureus resistant to penicillin G at a concentration of 0.78μg / ml. The resistant strains were also inhibited at a concentration of 25μg / ml. Most intestinal bacteria are very sensitive to Piperacillin,