李凤玲，姜卫abstract：objectivetoinvestigatetheclinicaleffectsofinhalingnitrousoideforanalgesialabor.methodsatotalof100casesofnormalpregnantwomenwereprovidedwithnitrousoidepromiedwithoygen(50∶50％)(controlgroup).another100caseswereprovidedonlywithoygen(parisongroup).recordingeffectoftheanalgesialabor,durationofthelabor，wayofdelivery,bleedingvolume，apgarsscore,bloodgasanalysistomatemalradiusarteryanetalumb...