Methods B7 expresion was studied by means of RT PCR and immunohistochemistry (IH) in 45 tumors of the urinary system.

• 方法应用逆转录?聚合酶链反应（RT?PCR）和免疫组织化学方法，检测45例泌尿系肿瘤B7基因在mRNA和蛋白水平的表达情况。