The other category is complexed calcium, which is where the positively charged calcium is ionically linked to tiny negatively charged molecules like oxalate, which is a small anion that are normally found in our blood in small amounts.

另一小组是结合钙，带正电的钙离子共价结合至微小的带负电的离子上，例如草酸盐离子；草酸盐是体积较小的阴离子，通常少量存在于血液中。