Term
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Definition
| A non-mitotic, or non-division, form of cell death that occurs when cells die without attempting division during the interphase portion of the cell life cycle or programmed cell death. |
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Term
| linear energy transfer (LET) |
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Definition
| average energy deposited per unit length of track |
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Term
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Definition
| When passing through a medium such as human tissue, ionizing radiation may interact with that medium during its passage, and as a result, lose energy along its path |
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Term
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Definition
| is used to display the radiosensitivity of a particular type of cell, which helps determine the types of cancer cells that will respond to radiation therapy. |
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Term
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Definition
| When low-LET radiation interacts with biologic tissue, it causes damage to a cell primarily through an indirect action that involves the production of molecules |
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Term
| Relative biologic effectiveness (RBE) |
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Definition
| the comparative capabilities of radiation with differing (LETs) linear energy transfer to produce a particular biologic reaction |
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Term
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Definition
| is the ratio of the radiation dose required to cause a particular biologic response of cells in an oxygen-deprived environment to the radiation dose required to generate an identical response under normal oxygenated conditions. |
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Term
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Definition
| It is direct when ionizing particles interact with a vital biologic macromolecule such as DNA. |
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Term
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Definition
| The action is indirect when ionizing particles interact with a water molecule, thus resulting in the creation of ions and reactive free radicals that eventually produce toxic substances that can create biologic damage. |
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Term
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Definition
| refers to the dissociation of molecules by ionizing radiation |
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Term
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Definition
| Interactions of ionizing radiation with DNA molecules may cause the loss of or change in a nitrogenous base on the DNA chain. |
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Term
| Law of Bergonié and Tribondeau |
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Definition
| the radiosensitivity of cells is directly proportional to their reproductive activity and inversely proportional to their degree of differentiation. Thus the most pronounced radiation effects occur in cells with the least maturity and specialization or differentiation, the greatest reproductive activity, and the longest mitotic phases. |
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Term
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Definition
| defending the body against foreign substances (antigens) by producing protective proteins (antibodies) to combat disease |
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Term
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Definition
| is devoid of blood vessels, and it regenerates through the process of mitosis. The cells are found in the lining of the intestines, the mucous lining of the respiratory tract, the pulmonary alveoli (tiny air sacs), and the lining of blood and lymphatic vessels. |
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Term
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Definition
| contains fibers that affect the movement of an organ or part of the body. Since muscle tissue cells are highly specialized and do not divide, they are relatively insensitive to radiation. |
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Term
| In living systems, biologic damage stemming from exposure to ionizing radiation is examined on three levels: |
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Definition
• Molecular
• Cellular
• Organic systems |
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Term
| When ionizing particles interact directly with vital biologic macromolecules such as: |
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Definition
• DNA
• Ribonucleic acid (RNA)
• Proteins
• Enzymes |
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Term
| The characteristics of ionizing radiation vary among different types of radiation. Characteristics include: |
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Definition
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Term
| Examples of Low-LET radiation is electromagnetic radiation |
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Definition
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Term
| Examples of High-LET radiation includes particles that possess substantial: mass and charge |
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Definition
• Alpha particles
• Ions of heavy nuclei
• Charged particles released from interactions between neutrons and atoms |
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