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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



complexes of proteins and lipids. Lipoproteins occur in plants and animals as constituents of all biological membranes and lamellar structures (in the myelin sheath of nerves, in the chloroplasts of plants, in the receptor cells of the retina). They occur in free form in blood plasma, from which they were first isolated in 1929.

Lipoproteins are classified according to chemical structure and lipid-protein ratio. They are subdivided into four main classes according to sedimentation rate during centrifugal separation: (1) high-density lipoproteins (52 percent protein and 48 percent lipids, primarily phospholipids), (2) low-density lipoproteins (21 percent protein and 79 percent lipids, mainly cholesterol), (3) very low-density lipoproteins (9 percent protein and 91 percent lipids, mostly triglycerides), and (4) chylomicrons (1 percent protein and 99 percent triglycerides).

It is thought that lipoprotein structure is micellar (the protein bonded to the lipid-cholesterol complex owing to hydrophobic interaction) or analogous to that of molecular compounds of proteins and lipids (the phospholipid molecules located in flexures of the polypeptide chains of protein subunits). The study of lipoproteins is complicated by the instability of lipid-protein complexes and by difficulties encountered in their isolation in natural form.


Finean, J. Biologicheskie ul’trastruktury. Moscow, 1970. (Translated from English.)


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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A regular feature of atherosclerosis and related conditions is a prevalence of cholesterol-rich low density lipoprotein and a paucity of protein-rich high-density lipoprotein, explain Kontush and Chapman (both dyslipidemia and atherosclerosis, National Institute of Health and Medical Research, Paris).
One theory is that the cholesterol is accompanied by unsaturated fat, which may raise levels of the good cholesterol (high-density lipoproteins).
As a possible drawback to GL701, women had lower blood concentrations of high-density lipoproteins, which make up so-called good cholesterol, after taking the drug than before.
After three months, all saw a drop in low-density lipoproteins (LDL's or "bad" cholesterol) from an average of 122 to 104, and an increase in high-density lipoproteins (HDL's or "good" cholesterol) from an average of 32 to 37.
A genotype conferring low activity of paraoxonase, an antioxidative enzyme in high-density lipoproteins, is linked to a threefold higher risk of myocardial infarction in men, reported Dr.
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It has been shown to raise levels of high-density lipoproteins (the good cholesterol) and reduce the incidence of heart disease, cancer, and stroke.
These include a decrease in the ability to form clots and an increase in the share of cholesterol residing in high-density lipoproteins (HDLs), the so-called good cholesterol.

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