Mellins H Z
Radiology. 1984 Nov;153(2):291-301. doi: 10.1148/radiology.153.2.6435168.
The ureteral bud in the embryonic kidney grows and branches dichotomously for 15 generations. This branching tree is modified by a series of narrowings and expansions and becomes the ureter, the renal pelvis, the calyces, and the collecting tubules. Simultaneously, the ureteral bud induces the formation of nephrons. If many of the renal cystic diseases and congenital dilatations of the renal pelvis and ureter are viewed as a series of growth disturbances along the branching ureteral bud, their morphology and pathophysiology become clarified even though their etiology is often not known.
胚胎肾中的输尿管芽生长并进行二叉状分支达15代。这一分支树通过一系列变窄和扩张而发生改变，进而成为输尿管、肾盂、肾盏和集合小管。同时，输尿管芽诱导肾单位的形成。如果将许多肾囊性疾病以及肾盂和输尿管的先天性扩张视为沿分支输尿管芽发生的一系列生长紊乱，那么即便其病因往往不明，它们的形态学和病理生理学也会变得清晰明了。
