Dept.of Medicine and Ra;
The Johns Hopkins University School of Medicine;
Baltimore;
Maryland Division of Gastroenterology;
San Francisco;
CA;
United States Drs;
Dept.of Medicine and Ra;
The Johns Hopkins University School of Medicine;
Baltimore;
Maryland;
Dept.of Medicine and Ra;
The Johns Hopkins University School of Medicine;
Baltimore;
Maryland Dr;
逆行胆管造影; 盲法; 硬化性胆管炎; 胆管疾病; 肝外胆管; 程度评估; 观测者; 附属医院; 诊断作用; 病例对照;