B Cells And T Cells
.... compared to a plasma cell that lives only a few days. Memory cells are made so they can recognize this same antigen if it were to ever reenter the body again.
Interactions between T cells are also known as the cell-mediated response. T cells are not just active against viruses and bacteria, but they also interact with eukaryotic cells. There are three types of T cells: helper T cells, suppressor T cells, and cytotoxic T cells. The T cell receptor (helper T cells) recognizes foreign antigens displayed on the surface of the body’s own cells. When the cytotoxic T cell encounters this, it differentiates into active cells .....
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Types Of Muscle
.... muscle is a special type of muscle found only in the heart. It consists of linked fibers that contract in unison producing the heartbeat.
Skeletal, or Striated Muscle Tissue:
This type of muscle is composed of long fibers surrounded by a membranous sheath, the sarcolemma. The fibers are elongated, sausage-shaped cells containing many nuclei and clearly display longitudinal and cross striations. Skeletal muscle is supplied with nerves from the central nervous system, and because it is partly under conscious control, it is also called voluntary muscle. Most skeletal muscle is attached to portions of the skeleton y connec .....
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A Link Between Anxiety And The Performance Of Athletes
.... can be thought of as a world view that in individual uses when coping with situations in his or her environment (Speilberger, 1996). Trait anxiety influences performances in that individuals with high trait anxiety will attend more information related to state anxiety (hardy et al., 1996). Now one of the earliest models that attempted to explain the relationship between arousal and performance was the inverted-U hypothesis. This performance stated that as arousal increased, performance would increase as well; but, if arousal became too great performance would deteriorate (Humara, 1999).
The effects of anxiety in athleti .....
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Klinefelter Syndrome
.... Syndrome can be diagnosed through a karyotype-a chromosome analysis usually done on a blood sample showing 47, XXY before birth, through amniocentesis or chorionic villus sampling (4). Neither procedure is routinely used to check for XXY though. In later years, a semen exam showing low sperm count, decreased serum testosterone level, increased serum luteinizing hormone or increases serum follice stimulating hormone, can be suspects for a male having Klinefelter Syndrome (1).
(2) Phenotype Characteristics
Frequency is about 1 in 500 to 1 in 1000 male births, which makes Klinefelter Syndrome a common disease. It doe .....
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The Safety Of Using Cell Phones
.... something important or especially is in the middle of an argument.” (Kolata, par. 2) The solution to cell phones in the cars is that cell phones should only be used in cases of emergencies.
The chance of brain tumors also increases with the usage of cell phones. Radiation emitted from cell phones is extremely hazardous to cell phone users’ well being. Experiments done in a Swedish laboratory have been done to test the affects of radiation emitted from cell phones. The conclusion of the experiment showed that, …the radiation from cellular phones might make it easier for poison to penetrate into the brain. The microwave .....
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The Use Of Supplements Creatine, Androstenedione, And HMB
.... Creatine phosphate(1).
Approximately 95% of the body’s Creatine supply are found in the skeletal muscles. The remaining 5% are scattered throughout the rest of the body, with the highest concentrations in the heart, brains, and testes. A skeletal muscle itself does not produce Creatine, but utilizes the Creatine originating in the liver and kidneys. The human body gets most of the Creatine; it needs from food or dietary supplements. Creatine is easily absorbed from the intestinal tract into the blood stream. When dietary consumption is inadequate to meet the body’s needs, a limited supply can be synthesized from the amino acids .....
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Bulimia Nervosa
.... eating binges, and half of them make the transition to bulimia. About 40% of the most severely bulimic patients have a history of anorexia. It is not clear whether the combination of anorexia with bingeing and purging is more debilitating, physically or emotionally, than anorexia alone. According to some research, anorectic women who binge and purge are less stable emotionally and more likely to commit suicide. But one recent study suggests that, on the contrary, they are more likely to recover.
The exact cause of the disorder is unknown, but a variety of psychological, social, cultural, familial and biochemical theories .....
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Biological And Chemical Weapons!!
.... niches, and continue to grow exponentially without termination. Because it hardly reaches a closure, biological weapons are not widely used. Nevertheless, history states it has been used during World Wars (I & II), cold war, and last but not least, also very recently in Tokyo, Japan by terrorists. Using such lethal weaponry kill people in exceptional amounts. Furthermore, it causes environmental degradation, spoiling our natural resources. Therefore, usage of mass destructive biological and chemical weapons, is a great threat to the existence of human species and our precious environment.
Biological Weapons
Biological weap .....
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Heart Cells
.... treatments might repair damaged hearts, such as those suffering congenital heart disease.
Scientist and researchers at the University of Udine in Italy, studied hearts removed from 27 people who had received transplants. The researchers stained slices of heart tissue half a micrometer thick and used a confocal microscope to count the individual cell nuclei caught in the process of division. Judging from these samples, They found that a estimate of 131 to 152 myocytes in every million were dividing.
That proportion suggests that the cells of a damaged ventricle could be replaced within a year, the researchers calculate. Howev .....
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The History And Facts About Nicotine And Tobacco
.... tobacco became the most important industry of the Virginia and Maryland colonies. Sometime later it became the major industry in North Carolina.
“The first of the tobacco manufacturers to mass-produce cigarettes was Washington, Duke and Sons of Durham, North Carolina (Theodore, 77).”
Tobacco is a highly addictive drug. This makes it very hard for heavy smokers to quit. Heavy smokers who do attempt to quit smoking will suffer many different painful withdrawal symptoms; some are psychological, such as moodiness and intense cravings. Others are physical such as gastrointestinal distress, sleep disturbances, lowered .....
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“That Time Of The Month”
.... about which device best suits their needs, can turn to this channel. To make it even more easy for them, the editors of the T.V. guide can list special “women ad” showings in its magazine just as it gives us listings of various shows shown throughout the day. This will not only aid a woman’s interest, but it will also soothe men’s hatred with these commercials.
The reason Jon has noticed his horrible luck with the T.V. today is because his girlfriend is on her period. Of coarse he knows the burdens of womanhood and realizes the unfortunate aspects of it, but he thought he might let the T.V. relax his angry confusion. He is in .....
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The Circulatory System
.... to the liver.
Coronary circulation is the means by which the heart tissues themselves are supplied with nutrients and oxygen and are freed of wastes. Just beyond the semiluna valves, two coronary arteries branch from the aorta.
Heart action consists of systole and relaxation of the muscular walls of the atria and ventricles. During the period of relaxation, the blood flows from the veins into the two atria. This action is sudden and occurs almost simultaneously in both atria. The mass of blood in the veins makes it impossible for any blood to flow backward. The ventricular systole immediately follows the atrial sys .....
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