Word: bloodstream
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Dates: during 1980-1989
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Well, yes. But it is also becoming evident that cholesterol can be either foe or friend, depending on the way it travels through the body. Cholesterol's sinister image derives from the fact that much of the substance is swept through the bloodstream by potentially damaging carrier particles called LDLs (for low-density lipoproteins). LDLs are called "bad" cholesterol because an excess of cholesterol carried by them can lead to the buildup of harmful deposits in the arteries. The other cholesterol carriers, known as HDLs (for high-density lipoproteins), are considered "good" because, far from being killers, they may actually...
Cholesterol in the bloodstream comes from two sources: it is produced naturally by the body's cells and also results from the intake of foods containing saturated fats or pure cholesterol -- for example, butter, cheese, liver, eggs and animal fat. In the Third World, where relatively little saturated fat and cholesterol are consumed, most people seem to be protected from heart disease by low LDL levels. The problem with the Western world's rich diet is that it puts the body into overdrive, so that more LDL cholesterol accumulates in the bloodstream than can be absorbed and used by cells...
Just how HDL plays its apparently vital role in ridding the body of excess cholesterol is not entirely clear. The substance is, after all, only one element in an alphabet soup of particles that make up the so-called lipid transport system, which moves cholesterol through the bloodstream. Though individual cells can make their own cholesterol, much of their supply comes from the bloodstream, arriving from the liver aboard macromolecular ferryboats, known as very-low-density lipoproteins, or VLDLs. These carrier particles are loaded in the liver with cholesterol and dietary fats known as triglycerides, which are used by cells...
...eras. In 1960 the candidates for the first time debated on television, and politics began an almost metaphysical transformation: the external world was miraculously reconvened as powdered images upon America's internal screen. Electrons fetched out of the air poured the circus directly into the living room, into the bloodstream -- just as they would inject Viet Nam into the center of American consciousness...
...almost every sport, there are some pills and potions that promise black- magic results. To fire their systems up, many competitors have turned to stimulants, using amphetamines or even caffeine enemas and suppositories, because rectal administration puts the chemical into the bloodstream without causing an upset stomach. Testing for "uppers" by sports federations is highly reliable, but use of this class of drugs is not confined to competitions like the Olympics. Some of the most famous cases of stimulant usage have occurred in professional baseball and football, which have lax testing for the substances...