Burns J R, Finlayson B
Invest Urol. 1980 Sep;18(2):133-6.
Equimolar concentrations of calcium chloride and potassium oxalate were precipitated by a rapid mixing technique. The precipitated calcium oxalate particles were repeatedly counted at 15 min with a Coulter counter until reproducible total particle count and particle distribution curves were obtained. These values were compared with those found after the addition of various seed crystals and 10 per cent urine to the system. Calcium oxalate seed crystals markedly enhanced the nucleation rate of calcium oxalate (1), although only an estimated 16 per cent acted as effective nucleators. The addition of sodium acid urate crystals resulted in a small decrease in the number of calcium oxalate particles precipitated and fewer than 0.1 per cent of the crystals acted as effective nuclei. Seeds of agglomerated hydroxyapatite crystals also produced a small decrease in the number of calcium oxalate particles and fewer than 1 per cent of the seeds functioned as nucleators. The addition of 10 per cent urine to the system greatly increased the number of calcium oxalate particles produced although we are uncertain whether the urine provided effective nuclei or prevented particle aggregation. Our data indicate that, in a rapidly mixed system, neither sodium acid urate nor hydroxyapatite crystals are effective nucleators for the precipitation of calcium oxalate. The occurrence of epitaxial growth of calcium oxalate on these substances in urinary stones is therefore called into question.
通过快速混合技术使氯化钙和草酸钾等摩尔浓度沉淀。用库尔特计数器在15分钟时反复计数沉淀的草酸钙颗粒，直到获得可重复的总颗粒数和颗粒分布曲线。将这些值与向系统中加入各种晶种和10%尿液后得到的值进行比较。草酸钙晶种显著提高了草酸钙的成核速率(1)，尽管估计只有16%的晶种起到了有效的成核作用。加入尿酸钠晶体导致沉淀的草酸钙颗粒数量略有减少，且不到0.1%的晶体起到了有效的晶核作用。团聚的羟基磷灰石晶体晶种也使草酸钙颗粒数量略有减少，且不到1%的晶种起到了成核作用。向系统中加入10%的尿液大大增加了产生的草酸钙颗粒数量，尽管我们不确定尿液是提供了有效的晶核还是阻止了颗粒聚集。我们的数据表明，在快速混合系统中，尿酸钠和羟基磷灰石晶体都不是草酸钙沉淀的有效成核剂。因此，草酸钙在尿路结石中的这些物质上外延生长的发生受到质疑。
