growth curve


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curve

 [kerv]
a line that is not straight, or that describes part of a circle, especially a line representing varying values in a graph.
dose-effect curve (dose-response curve) a graphic representation of the effect caused by an agent (such as a drug or radiation) plotted against the dose, showing the relationship of the effect to changes in the dose.
growth curve the curve obtained by plotting increase in size or numbers against the elapsed time.
oxyhemoglobin dissociation curve a graphic curve representing the normal variation in the amount of oxygen that combines with hemoglobin as a function of the partial pressures of oxygen and carbon dioxide. The curve is said to shift to the right when less than a normal amount of oxygen is taken up by the blood at a given Po2, and to shift to the left when more than a normal amount is taken up. Factors influencing the shape of the curve include changes in the blood pH, Pco2, and temperature; the presence of carbon monoxide; alterations in the constituents of the erythrocytes; and certain disease states.
pulse curve sphygmogram.
Spee curve (curve of Spee) the anatomic curvature of the occlusal alignment of teeth, beginning at the tip of the lower canine, following the buccal cusps of the premolars and molars, and continuing to the anterior border of the ramus.
strength-duration curve a graphic representation of the relationship between the intensity of an electric stimulus at the motor point of a muscle and the length of time it must flow to elicit a minimal contraction; see also chronaxie and rheobase. In cardiac pacing it is useful in determining characteristics of a particular pacing electrode and determining the most efficient selection of pacing parameters for an appropriate safety margin.
survival curve a graph of the probability of survival versus time, commonly used to present the results of clinical trials, e.g., a graph of the fraction of patients surviving (until death, relapse, or some other defined endpoint) at each time after a certain therapeutic procedure.

growth curve

a graphic representation of the change in size of an individual or a population over a period of time.

growth curve

a graphic display of data showing proliferation of cell numbers in a culture as a function of time.
Growth curveclick for a larger image
Fig. 182 Growth curve . A growth curve in a microbial culture.
Growth curveclick for a larger image
Fig. 181 Growth curve . (a) Exponential. (b) Logistic.

growth curve

the graphic representation of the growth of a population, which could be exponential where (theoretically) the density would eventually be increasing at an infinite rate, or could be logistic (see LOGISTIC CURVE where the density would stabilize near the CARRYING CAPACITY of the population. See Fig. 181 . Populations of microorganisms tend to go through a classic four-stage growth curve (see Fig. 182 ). The ‘lag’ phase is a time of adaptation to the new environment where such processes as ENZYME INDUCTION take place and reproduction rate equals death rate. The ‘log’ phase is a period of exponential growth (reproduction rate much greater than death rate). The ‘stationary’ phase is a time of equilibrium, representing the response to a limiting factor such as nutrient source, while little or no reproduction occurs during the ‘death’ phase, so the population declines.

growth curve

a graph of change-in-height against age, which shows the greatest rate of change in infancy, flattening off until the growth spurt which on average reaches a peak at about age 12 in girls and 14 in boys.

growth

1. the progressive increase in size of a living thing, especially the process by which the body reaches its point of complete physical development.
2. an abnormal formation of tissue, such as a tumor.

growth arrest line
a radiologically detectable line parallel to the growth plate in the metaphysis that indicates a temporary cessation of bone growth.
growth check
an event or state, usually the result of inadequate nutrition, parasitism or other disease, which temporarily reduces or stops growth in a young animal. Often followed by a period of compensatory growth.
compensatory growth
increased growth rate during a time period as a result of lower than normal growth rate during a previous period.
growth cone
bulbous enlargement at the tip of every growing axonal fiber in the fetus, from which many long filapodia extend.
growth curve
the curve obtained by plotting increase in size or numbers against the elapsed time.
growth disorders
are sometimes traceable to excess or shortage of pituitary secretions, and may arise from hereditary defects or from glandular abnormalities. Abnormally large secretions of growth hormone can produce gigantism. Failure of the pituitary gland to develop sufficiently or to secrete adequate amounts of growth hormone may result in dwarfism. In adulthood, overproduction of growth hormone may lead to acromegaly.
growth factor
substances which act as local regulators of cell division and function; classified as autocrine (act on cells of the same class) or paracrine (act on cells of a different class).
hematopoietic growth factors
see colony-stimulating factors.
one-step growth curve
a plot typical of the rapid growth of a virus in cell culture when all cells are infected simultaneously.
growth plate
the epiphyseal cartilage at which new bone formation occurs to lengthen long bones during their growth phase. Called also physis. See also epiphyseal plate.
growth promotants
includes all agents used to increase the rate of body weight gain. Used principally in food animals but also in horses with a view to increasing muscle mass and physical performance, and in any species to hasten recuperation in animals debilitated by illness. Pharmaceutical preparations are principally anabolic steroids. Husbandry procedures include estrogen and zearalenone implants and dietary supplementation with antibiotics, monensin and, in the case of pigs, copper.
growth rate
rate of increase in body weight per unit of time, e.g. lb/day in beef cattle.
recombinant growth factor
recombinant growth hormone.
growth retardation
stature smaller than normal; called also runt.
growth retardation lattice
radiodense metaphyseal lines parallel to the epiphyseal plate developing in fetal bone.
transforming growth factor [beta]
a family of extracellular signaling molecules important in the transformation of cells and in growth and development.
References in periodicals archive ?
Estimation of growth curve parameters and analysis of year effect for body weight in Hanwoo.
Estimation of Growth Curve Parameters for Body Weight and Measurements in Castrated Hanwoo (Bos taurus Coreanae).
Estimation of growth curve for evaluation of growth characteristics for Hanwoo cows.
0], initial weight; m, the slope of growth curve at the initial specific growth rate; D, the rate of exponential decay of the initial specific growth rate m, which measures rate of growth decline.
The objective of this study was to measure body conformation traits as well as ultrasound LMA and BFT in Hanwoo breeding stock (cows) in Gyeongbuk province, Korea, and to estimate the parameters of Gompertz growth curves.
SPSS statistical software was used to determine growth curves of the various measurements.
Except for the constant factor of 100, the two curves are not perceptibly different (on the scale chosen) and represent an exponential increase at the rate of 3 percent per year The literature growth curve taken alone represents also the usual view of an "information explosion.
The growth curve of a scientific literature: Nitrogen fixation by plants.
Nonetheless the idealized growth curves shown in Figure 2 lead to certain conclusions that are unlikely to be much different if real data were used.
As the digital still camera market heads into the end of its growth curve, certain metrics will become more standardized around the world," said Christopher Chute, senior analyst for IDC's Digital Imaging Solutions and Services.
Additionally, IDC predicts that the worldwide DSC market, which entered early maturity last year, will continue to mature across the world as emerging markets experience strong growth curves and older markets begin to decline.
Kagan forecasts bigger revenue growth curves for cable nets in the next several years, with projected growth of 32% from 2002 to 2010, versus 12.