protective-[医] 保护疗法protectiveadj.保护的；防卫的protective covenant保障约定protective hardware保护金具protective benefits防护效能protective isolator保护性隔离物protective antibody保护性抗体protective earthlng保护接地protective relaying继电保护protective property保护性能protective forestry防护林protective envelope保护层[套； 膜； 外壳]