aD3 is nonactive vitamin D before C25 hydrooxyaction in liver cell, so it become 1.25(OH)2D3. The active vitamin D can improve Ca, P to be absorbed in intestine and renal tube and inhibit parathyroid cell proliferation to decrease the product of PTH.是什么意思_aD3 is nonactive vitamin D before C25 hydrooxyaction in liver cell, so it become 1.25(OH)2D3. The active vitamin D can improve Ca, P to be absorbed in intestine and renal tube and inhibit parathyroid cell proliferation to decrease the product of PTH.在线翻译_英语_读音_用法_例句