内窥镜‖，内视镜一种目测检查身体通道或中空器官，如结肠|、膀胱或胃的内部的仪器 An instrument for examining visually the interior of a bodily canal or a hollow organ such as the colon, bladder, or stomach.
尿道大多数哺乳动物自上尿液从膀胱中排出体外的管道|，雄性的精子可从中排出 The canal through which urine is discharged from the bladder in most mammals and through which semen is discharged in the male.
