患者男性,55岁。因头晕、便秘、排便习惯改变来就诊。否认有胃切除。体检无特殊发现。实验室检查:RBC3.4×1012/L,Hb83g/L。MCV72fl,MCH26pg,MCHC30%,血清铁8μmol/L(正常9~27μmol/L),铁结合力75μmol/L(正常45~66μmol/L),铁饱和度10%(正常20%~40%),铁蛋白10gg/L(正常15~400μg/L)。为了进一步明确患者贫血的原因,下一步应考虑做的检查有()
A. 网织红细胞计数
B. 血清叶酸测定
C. 铁吸收试验
D. 大便隐血试验
E. 胃镜
F. 幽门螺杆菌抗体
G. 乙状结肠镜检查
Bank of China informs the beneficiary, a Chinese import and export company that a foreign bank has opened a letter of credit in his favor. The bank does not add its engagement by informing the beneficiary. The Bank of China ia acting as ().
A. The issusing bank
B. The advising bank
C. The confirming bank
D. The negotiating bank