medullary substance的用法和样例：
例句
- Markers of kidney damage, such as proteinuria or small kidney size, can be observed in many young gout subjects with medullary nephrocalcinosis.
肾脏伤害的标记，例如蛋白尿与肾脏缩小，常可见于年轻的痛风并发肾髓质钙化症的病人中。 - This rare renal tumor shows differentiation towards medullary collecting tubules.It is usually centered on the medulla with extension towards the cortex.
肾集合管癌较少见，主要发生于肾髓质内，病变可向肾皮质扩展。
