Word: bloodstream
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Dates: during 1980-1989
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...natural pesticides in sweat, saliva and tears, dissolved by stomach acids or trapped in the sticky mucus of the nose or throat before being expelled by a sneeze or a cough. But the organisms are extraordinarily persistent, and some occasionally breach the outer defenses. After entering the bloodstream and tissues, they multiply at an alarming rate and begin destroying vital body cells...
Early-warning cells constantly monitor the bloodstream and tissues for signs of the enemy. With the gusto of Pac-Man, they gobble up anything that is foreign to the body. They envelop dust particles, pollutants, microorganisms and even the debris of battle: remnants of invaders and infected or damaged body cells. Other early warners direct the production of unique killer cells, each designed to attack and destroy a particular type of intruder. Some of the killers, alerted to body cells that have become cancerous, may annihilate these...
...immune system. For reasons that are not yet clear, immune cells invade the pancreas and destroy the beta cells, which produce insulin. When this happens, the body cannot convert sugar into the energy that cells need to function. The cells starve, and the unconverted sugar builds up in the bloodstream, damaging the fragile lining of blood vessels. Complications associated with Type 1 diabetes include heart and kidney disease, poor circulation, eye problems and stroke...
...eventually kill enough cells to cause death. But the intruders soon encounter roving scavenger cells called phagocytes, which simply engulf and digest them. These defenders -- monocytes, neutrophils and macrophages -- secrete substances that dilate nearby blood vessels and make them more permeable, enabling even more defenders to get from the bloodstream to the infection site. Other proteins, those belonging to the complement system, aid in this process...
...responses of the immune system slow, then shut down. Scientists believe that still other immune specialists, known as suppressor T cells, call off the battle. As the carnage wanes, the B cells and T cells perform a last, vastly important task: they form memory cells that circulate in the bloodstream and lymph system for many years, primed to spring into action should the same strain of flu virus ever attack again. In addition, the body is protected by specialized antibodies, strategically deployed in mucus, saliva and tears, that immediately recognize any return of this particular virus...