They also look at whether that cholesterol is being shuttled by low-density lipoproteins or LDL, the so-called 'bad' cholesterol, and high density lipoproteins or HDL, the 'good' cholesterol.

他们观察是否胆固醇被低密度脂蛋白（LDL）运送，叫做“坏”胆固醇，和高密度脂蛋白HDL，就是“好”胆固醇。