Abstract：
Nitrous oxide is used medically as an anesthetic agent; in the food industry as a propellant for condiments; and recreationally for its euphoric and dissociative effects. We report three cases of nitrous oxide misuse causing severe, symptomatic cobalamin (vitamin B12) deficiency in which signs of nitrous oxide use per se, as well as signs of toxicity, were observed, including characteristic palmar calluses over the metacarpal heads, and frostbite. These signs may assist clinicians in the recognition of nitrous oxide use and the timely diagnosis of nitrous oxide toxicity.
摘要：
一氧化二氮在医学上用作麻醉剂；在食品工业中用作调味品的推进剂；并因其欣快感和解离作用而消遣。我们报告了三例一氧化二氮误用导致严重的，有症状的钴胺素（维生素B12）缺乏，其中一氧化二氮的迹象本身使用，以及毒性的迹象，被观察到,包括掌骨头上的特征性掌骨老茧,还有冻伤.这些体征可能有助于临床医生识别一氧化二氮的使用并及时诊断一氧化二氮的毒性。
