Söhnel O, Grases F, Garcia-Ferragut L
University Illes Balears, Dept. Chemistry, Palma de Mallorca, Spain.
Scanning Microsc. 1994;8(3):513-21; discussion 521-2.
Possible effects of crystal agglomeration on the early stages of calcium oxalate papillar stone formation are evaluated. The collecting ducts are filled with liquid that flows laminarly as established through hydrodynamical and physicochemical considerations. Under such conditions, agglomeration due to laminar shear forces proceeds. Agglomeration of calcium oxalate monohydrate crystals present in urine at a concentration typical for clinically observed crystalluria cannot result in the formation of a particle sufficiently large enough to be retained in the Bellini's duct and become a papillar stone nidus (nucleus). Formation of such an aggregate during the passage time of urine through the duct requires an unrealistically high concentration of crystals in urine, one that exceeds the normal content of urinary oxalate by several orders of magnitude. Aggregates obstructing the Bellini's duct as assumed in the free particle theory cannot represent a major factor in stone formation. This conclusion is corroborated by experimental results and other observations.
评估了晶体团聚对草酸钙乳头石形成早期阶段的可能影响。集合管中充满了根据流体动力学和物理化学因素确定的呈层流流动的液体。在这种条件下，由于层流剪切力会发生团聚。尿液中存在的一水合草酸钙晶体以临床观察到的结晶尿典型浓度进行团聚，不会形成足够大的颗粒以保留在乳头管中并成为乳头石病灶（核心）。在尿液通过管道的时间内形成这样的聚集体需要尿液中晶体浓度高到不切实际的程度，即超过尿草酸正常含量几个数量级。自由颗粒理论中假设的阻塞乳头管的聚集体不可能是结石形成的主要因素。这一结论得到了实验结果和其他观察结果的证实。
