Malek R S, Boyce W H
J Urol. 1977 Mar;117(3):336-41. doi: 10.1016/s0022-5347(17)58451-7.
Conventional and scanning electron microscopy of calcigerous renal calculi discloses typical concentric laminations, radial striations and microspherules. Random axial distribution of oxalate crystals and their coating by electron-dense matrix fibers with a definite parallel orientation and cross-linkages are evident. The biochemical relationship of uromucoid to matrix substance A is described. It is suggested that renal sialidase may convert the urinary uromucoid to matrix substance A, whose apatite-covered fibers may be responsible for epitaxial nucleation of some crystal systems. Our studies indicate that the intimate apatite-matrix relationship occurs in the human nephron, probably as an intracellular phenomenon. Subsequent extrusion of these mineralized complexes into the lumen of the nephron (intranephronic calculosis) may, in some instances, represent the initial microanatomic stage of renal calculogenesis.
含钙肾结石的传统显微镜检查和扫描电子显微镜检查显示出典型的同心层状结构、放射状条纹和微球。草酸钙晶体随机轴向分布，且被具有明确平行取向和交联的电子致密基质纤维包裹，这一点很明显。描述了尿类黏蛋白与基质物质A的生化关系。有人提出肾唾液酸酶可能将尿中的尿类黏蛋白转化为基质物质A，其被磷灰石覆盖的纤维可能是某些晶体系统外延成核的原因。我们的研究表明，磷灰石与基质之间的紧密关系发生在人类肾单位中，可能是一种细胞内现象。这些矿化复合物随后排入肾单位管腔（肾内结石形成），在某些情况下，可能代表肾结石形成的初始微观解剖阶段。
