text: <unk> -density lipoprotein (HDL) does not represent one structure but rather a series of lipoproteins that are sequentially produced.  HDL dynamically switches between different conformations. Fractionated HDL particles can be classified based on physiochemical properties, cholesterol component, apolipoprotein composition, electrophoretic mobility, density, and biological function.  HDL concentration in the serum can be classified into either low and<unk>  when the serum HDL concentration ≥ 60mg/dL and < 40 mg/dL, respectively.
option_0: High density lipoprotein classification
option_1: Low density lipoprotein classification
option_2: Hyperlipoproteinemia classification
option_3: Lipoprotein disorders classification
option_4: Non-alcoholic fatty liver disease classification
option_5: Hypoglycemia classification
option_6: Hyperkalemia classification
option_7: Atherosclerosis classification