直肠肛管手术后出现尿潴留的原因可能有() ["伤口疼痛","骶管麻醉","敷料填塞过多","术中输液过多","不习惯床上排尿"]
气压焊接弯曲试验可在()上进行;压焊面应处在弯曲中心点,弯至90°,3个试件均不得在压焊面发生破断。 ["万能试验机","手动液压弯曲试验器","电动液压弯曲试验器","拉伸试验机","弯曲试验机"]
血清中常规检查不到的HBV标志物是() ["HBsAg","HBeAg","HBcAg","抗-Hb","抗-HBc"]
男,32岁。饭后因车祸致骨盆骨折,右股骨干开放性骨折。体温38.9℃,血压50/20mmHg,脉搏130次/分,呼吸20次/分。术前未置胃肠减压管,拟急诊行股骨干骨折切开复位内固定术。最佳的麻醉方案是() ["A.硬膜外阻滞","腰麻","全麻","局麻","脊麻-硬膜外联合阻滞"]
下列哪种肝炎病毒不属于RNA病毒() ["HAV","HBV","HCV","HDV","HEV"]
简述危重型哮喘的治疗原则。