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Single-compartment models

Models may contain any number of compartments but single-compartment models are generally inaccurate for studying pharmacokinetics. A three-compartment model allows fairly accurate modelling with only limited complexity. [Pg.109]

The terminology for the so-called central compartment is Q. There are various rate constants that should be included in the diagram K01 is the rate constant for a drug moving from the outside of the body (compartment 0) to the central compartment (compartment 1) K10 is the rate constant of elimination from Ci to C o- Single-compartment models do not occur physiologically. [Pg.109]

Figure 2.4 Single compartment model for the uptake and release of hydrophobic organic compounds. The a/w subscript refers to air or water. Figure 2.4 Single compartment model for the uptake and release of hydrophobic organic compounds. The a/w subscript refers to air or water.
In the model shown in Figure 13.1, if CL12 is very large compared to CLw, and if no data shortly after administration of a bolus dose are available, the model would behave as a single compartment model, and CL12 will not identifiable also, only the sum of the volumes rather than both volumes separately can be assessed. [Pg.347]

Figure 6.12 (a) Semilog plot of plasma concentration (Cp) versus time. Cp° is the intercept on the y-axis, and Kei is the elimination rate constant, (b) Single compartment model with rate constants for absorption, K, and for elimination, Kcl. [Pg.108]

C. Cox, T.W. Clarkson, D.O. Marsh, L. Amin-Zaki, S. Tikriti, and G.G. Myers, Dose-response analysis of infants prenatally exposed to methyl mercury An application of a single compartment model to single strand hair analysis. Environ. Res. 49 318, 1989. [Pg.86]

Sweeney, R.E., Maxwell, D.M. (2003). A theoretical expression for the protection associated with stoichiometric and catalytic scavengers in a single compartment model of organophosphorus poisoning. Math. Biosci. 181 133 3. [Pg.1030]

Compartmental analysis is an extension of the simple, single compartment models (Sections 5.1 and 5.2.1) to include multiple compartments. It is far more commonly apphed in medical studies or in other ecosystems than the marine environment. Even for the soil, plant, and limnological communities have appHed the... [Pg.1369]

Pharmacokinetics provides the scientific basis of dose selection, and the process of dose regimen design can be used to illustrate with a single-compartment model the basic concepts of apparent distribution volume (Vd), elimination half-life (b/2) and elimination clearance (CLg). A schematic diagram of this model is shown in Figure 2.4, along with the two primary pharmacokinetic parameters of distribution volume and elimination clearance that characterize it. [Pg.13]

FIGURE 2.4 Diagram of a single-compartment model in which the primary kinetic parameters are the apparent distribution volume of the compartment (V ) and the elimination clearance (CLg). [Pg.13]

Equation 2.4 was derived by substituting CLR/Vi for k in Equation 2.13. Although Ud and CLr are the two primary parameters of the single-compartment model/ confusion arises because k is initially calculated from experimental data. However/ k is influenced by changes in distribution volume as well as clearance and does not reflect just changes in drug elimination. [Pg.19]

Because the single-compartment model implied by this equation makes no provision for the contribution of intercompartmental clearance to elimination half-life, estimates of Vdiarea) are larger than V iss)-... [Pg.34]

The reason that Pd(ss) is smaller than either of these two estimates is that neither the half-life equation used to calculate Vd(area) I ior the single-compartment model implied in calculating naakes any provision... [Pg.532]

Lidocaine pharmacokinetics tend to follow a single compartment model in neonates, with an increased half-life, and substantially reduced protein binding, leading to a much larger volume of distribution than in adults, but an increased proportion of unbound drug (56). [Pg.2056]

Human Studies. Estimates for the half-lives for elimination of PCBs from humans have been based on body burden measurements at two or more time points form the same individual. A simple mass balance approach is commonly employed to characterize the elimination of PCBs from humans. In general, a simplified single compartment model is used where only intake and first order elimination are assumed to occur. In most cases, the intake is assumed to be negligible and the following equation is used to estimate k, the first order loss or rate constant (day ), where C and Cj are the initial and final tissue concentrations, respectively, and t is the time between sampling. [Pg.359]

Gaffney (USA) 2008 Cleaning semiconductor wafers simulation study results compared to steady-state, single compartment model Methanol Short-term (15-min) and long-term (2 to 4-hr) personrd and area samples (ppm)... [Pg.752]

The elimination of methylmercury in humans can be described by a single-compartment model with a half-time of 39-70 days [37,38]. The excretion mechanism of inorganic mercury is much more complicated. In addition to fractions with short half-times of a few days or weeks for most of the absorbed mercury, there is a long one which probably lasts years [39-42]. Biochemical inactive mercury-selenide compounds may be responsible for this extremely long half-time of small quantities of inorganic mercury. [Pg.483]

Single compartment models are desirable in this work, because any interaction between the mathematical models and the corresponding experimental systems should be based on the same known quantities. It would not be reasonable to include variables in the models that either cannot be determined from separate equations or cannot be provided as an input from the available experimental data. To check and validate models, we are using microscopy and imaging techniques to capture dynamic calcium events taking place within a cell as a whole, as opposed to calcium diffusion across a cell or intracellular calcium waves, for example (Patterson et al., 2007). [Pg.97]

If not given, the rate constant can be derived from the half-life and equation 6-5. A single-compartment model is based on the assumption that an injected drug is instantaneously distributed in the plasma and tissues. Such a model is a good starting point and applicable in many situations. [Pg.247]


See other pages where Single-compartment models is mentioned: [Pg.414]    [Pg.366]    [Pg.37]    [Pg.210]    [Pg.64]    [Pg.215]    [Pg.214]    [Pg.359]    [Pg.31]    [Pg.196]    [Pg.122]    [Pg.753]    [Pg.111]    [Pg.38]    [Pg.214]    [Pg.164]    [Pg.208]    [Pg.1100]   
See also in sourсe #XX -- [ Pg.11 ]




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