| aging | The gradual changes in the structure and function of humans and animals that occur with the passage of time, that do not result from disease or other gross accidents, and that eventually lead to the increased probability of death as the person or animal grows older. It does not apply to microorganisms. (12 Dec 1998) |
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| aging, premature | Changes in the organism associated with senescence, occurring at an accelerated rate. (12 Dec 1998) |
| cell aging | The decrease in the cell's ability to proliferate with the passing of time. Each cell is programmed for a certain number of cell divisions and at the end of that time proliferation halts. The cell enters a quiescent state after which it experiences cell death via the process of apoptosis. (12 Dec 1998) |
| clonal aging | The deterioration in successive generations of a clone; thus paramecia and other simple forms, if allowed to reproduce asexually for a number of generations, invariably undergo deterioration, the characters of each group of descendants progressively departing from those of the original sexually produced ancestor. (05 Mar 2000) |
| skin aging | The process of aging due to changes in the structure and elasticity of the skin over time. It may be a part of physiological aging or it may be due to the effects of ultraviolet radiation, usually through exposure to sunlight. (12 Dec 1998) |
| erythrocyte aging | Senescence of the red blood cell. Lacking the organelles that make protein synthesis possible, the mature erythrocyte is incapable of self-repair, reproduction, and carrying out certain functions performed by other cells. This limits the average life span of an erythrocyte to 120 days. (12 Dec 1998) |
| relief work | Assistance, such as money, food, or shelter, given to the needy, aged, or victims of disaster. It is usually granted on a temporary basis. (12 Dec 1998) |
| rescue work | Activities devoted to freeing persons or animals from danger to life or well-being in accidents, fires, bombings, floods, earthquakes, other disasters and life-threatening conditions. While usually performed by team efforts, rescue work is not restricted to organised services. (12 Dec 1998) |
| work | <chemistry> Energy transferred by mechanical means, force acting over a distance. For chemical systems the sign for work is positive, if work is done on the system and negative, if work is done by the system. An example is the expansion of a gas against the external, atmospheric pressure. In this case work is negative, because it is done by the gas which represents the system. (09 Jan 1998) |
| work capacity evaluation | Assessment of physiological capacities in relation to job requirements. It is usually done by measuring certain physiological (e.g., circulatory and respiratory) variables during a gradually increasing workload until specific limitations occur with respect to those variables. (12 Dec 1998) |
| work of breathing | Respiratory muscle contraction during inspiration. The work is accomplished in three phases: that required to expand the lungs against its elastic forces (lung compliance work), that required to overcome the viscosity of the lung and chest wall structures (tissue resistance work), and that required to overcome airway resistance during the movement of air into the lungs (airway resistance work). Work of breaking does not refer to expiration, which is entirely a passive process caused by elastic recoil of the lung and chest cage. (guyton, textbook of medical physiology, 8th ed, p406) (12 Dec 1998) |
| work schedule tolerance | Physiological or psychological effects of periods of work which may be fixed or flexible such as flexitime, work shifts, and rotating shifts. (12 Dec 1998) |
| work simplification | The construction or arrangement of a task so that it may be done with the greatest possible efficiency. (12 Dec 1998) |
| social work | The use of community resources, individual case work, or group work to promote the adaptive capacities of individuals in relation to their social and economic environments. It includes social service agencies. (12 Dec 1998) |
| social work department, hospital | Hospital department responsible for administering and providing social services to patients and their families. (12 Dec 1998) |