【摘要】 目的　通过检测大鼠孕早期超声辐照后其胎盘组织中一氧化氮合酶 (nitricoxidesynthetase,NOS)活性及一氧化氮(niticoxide ,NO)含量的阶段变化 ,旨在为临床孕早期超声诊断的安全性评价提供一定的实验依据。方法　将孕鼠分期采用生化技术检测其胎盘组织中相关生化指标的变化。结果　NOS活性与NO含量测定 ,孕早期实验组均明显低于对照组 (P <0 0 1) ,中晚期与对照组相比已无显著性差异。结论　孕早期接受一定剂量的超声辐照可使NO含量和NOS活性下降更多还原

【Abstract】 Objective To assess the changes of NOS and NO levels after exposing ultrasonic diagnostic dosage to early pregnancy rats. Methods Biochemical technique was adopted to study the changes of NO and NOS metabolism. Results The NOS and NO levels were significantly lower in treated groups than in control group ( P <0 01) in early pregnancy, however, in the middle and later pregnancy there was no difference between 2 groups. Conclusion Diagnostic ultrasound in early pregnancy can make NO and NOS levels decrease.更多还原