before opemtlon的用法和样例：
例句
- Conclusion Ultrasuond is a useful tool to find the acute appendicitis diverticulitis before the operation.
结论腹部超声是术前诊断急性阑尾憩室炎的一种有价值的检查方法。 - We analyzed the risk factors associated with failing to optimally administer preoperatie antibiotics before primary hip and knee arthroplasty.
我们在这里就分析了初次髋膝关节成形术前的最佳抗生素应用方式失败的危险因素。
