IMMUNE SYSTEM is the system which facilitates the
reaction of the body to substances that are foreign or are interpreted as being foreign. It is one
of the most important body defenses against disease or the actions of certain poisons. There are
many types of immunity. Natural immunity is an inborn protection. Acquired immunity occurs as a
result of antibodies. This latter form of immunity comes in two types: active and passive.
Active immunity results when a person produces his or her own
antibodies in response to the presence of an antigen. Natural active immunity is obtained while the
person is recovering from an actual infectious disease. Artificial active immunity is the result of
vaccines containing antigens which, when introduced into the body, cause production of immunizing
antibodies.
Passive immunity results when antibodies are introduced into
the body from an outside source. Since no antigen is introduced, there is no stimulus for the
production of any new antibodies. Therefore, passive immunity is of short duration, lasting only as
long as the introduced antibodies remain active in the body. Natural passive immunity is the
congenital immunity transferred from the mother to her unborn child.
IMPOTENCE - Mother Nature's way of saying, "No Hard
Feelings."
INFARCTION - An infarction is the local arrest or sudden
or insufficiency or arterial or venous blood supply due to emboli, thrombi, vascular torsion or
pressure that produces a macroscopic area of necrosis cell death; the heart, brain, spleen, kidney,
intestine, lung and testes are most affected, as are tumors, especially of the ovary or uterus.
INSANE: Selectively perceptive.
INSULIN is a peptide hormone made of two polypeptide
chains, and is secreted from the beta cells of the pancreas. The function of insulin is to increase
the ability of certain organs, such as muscles and the liver, to utilize glucose and amino acids.
Insulin also increases the total quantity of protein in the body by increasing the flow of amino
acids into cells, accelerating messenger RNA translation, and increasing DNA transcription to form
more RNA. Insulin is essential for the proper metabolism and proper maintenance level of blood
sugar. Secretion is primarily dependent upon the concentration of blood glucose, an increase of
blood sugar bringing about an increase in the secretion of insulin. Inadequate secretion of insulin
results in improper metabolism of carbohydrates and fats and brings on diabetes, characterized by
glucose accumulating in the blood and wastefully excreting in the urine. Various forms of insulin
may be prepared and administered to temporarily treat a diabetic individual.
INTERCELLULAR describes something which is shared, or a
process which occurs, between two or more cells in a structure.
INTERFERON is a protein produced by cells in response to
active or inactive viruses and certain bacteria. Non-infected cells exposed to interferon become
protected against the viral infection. Interferons are specific for cells and not for viruses, thus
different cells will produce different interferons to the same virus. Research is presently being
conducted to ascertain its medical usefulness. Vitamin C and germanium sesquioxide have both been
shown to stimulate the body's natural production of interferons.
INULIN is a polysaccharide found in artichoke, asparagus,
and other plants. Inulin is formed of 30 fructose units joined together. It is used for diagnosis
of kidney functions. Inulin is injected into the bloodstream and, after an appropriate time delay,
its concentration is checked for in the urine and bloodstream.
ION - an ion is an atom or molecule which carries an
electric charge; it can be either a cation or an anion.
ISOFLAVONOIDS are a class of compounds grouped together
due to similar chemical structure. Isoflavonoids are found in red clover tops, alfalfa, and many
other plants. The activity of these isoflavonoids produces estrogenic hormone-like effects.
IN VITRO studies refer to those experiments which are
performed on tissue culture systems or in a test tube. Tissue culture is a method by which cancer
or normal cells are grown in plastic or glass laboratory dishes containing adequate nutrients. This
method is commonly used in biomedical research because it is simple, sensitive, cost-effective and
efficient.
ISOMERS are two or more compounds with identical chemical
composition with respect to mass, number, and type of atoms, and which differ only in the
arrangement of these atoms in space. |