正常成年人肾脏,已去除肾包膜。肾脏仍保持着胚胎时的小叶形态（成年人有时保留着胚胎时的小叶形态）。位于左侧中部的肾门处有一些脂肪组织。右下有一个表面光滑、充满清亮液体的单纯性肾脏小囊肿。囊肿可以单发，也可散在于肾脏实质周围。囊肿在成年人并不罕见。
Here is a normal adult kidney. The capsule has been removed and a pattern of fetal lobulations still persists, as it sometimes does. The hilum at the mid left contains some adipose tissue. At the lower right is a smooth-surfaced, small, clear fluid-filled simple renal cyst. Such cysts occur either singly or scattered around the renal parenchyma and are not uncommon in adults.
