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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:dateCreated |
1992-8-10
|
| pubmed:abstractText |
The elimination rate of drug from a capacity-limited one-compartment model can be expressed by equation (1): [formula: see text] Traditionally equation (1) was linearized according to equation (2): [formula: see text] Here, an alternative linear relationships between concentration and the area under the curve of C/(Km + c]) is proposed: [formula: see text] By iteration of Km into equation (3) until the statistic of analysis of variance for the regression is maximized, both Km and Vmax can be obtained. Several cases were considered: a) Intravenous bolus (single dose): Km (mg/L), Vmax (mg/L h), Vd (L) and V (mg/h) can be estimated. b) Extravascular administration (single dose): by the method of residuals it is possible to make additional estimations of FD/Vd (mg/L) and Ka (1/h). c) Bioequivalence studies: with parameters obtained at single dose, the simulated levels at steady-state are considered for the bioequivalence assessments. d) Km, Vmax estimation with two (C,t) points (single dose): double iteration (Km values and interpolated fictitious third points) are needed. e) Multiple dose: [formula: see text] If t2-t1 = T (interval of administration) it is possible to calculate operatives Km, Vmax, FD/Vd and to estimate Css (steady-state concentration). C1 and C2 correspond to different intervals. All the areas were calculated by the trapezoidal rule.
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| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:issn |
0378-7966
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
Spec No 3
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
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| pubmed:pagination |
485-96
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| pubmed:dateRevised |
2011-2-2
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| pubmed:meshHeading |
pubmed-meshheading:1820928-Biological Availability,
pubmed-meshheading:1820928-Biotransformation,
pubmed-meshheading:1820928-Humans,
pubmed-meshheading:1820928-Injections, Intravenous,
pubmed-meshheading:1820928-Models, Biological,
pubmed-meshheading:1820928-Pharmacokinetics,
pubmed-meshheading:1820928-Phenytoin,
pubmed-meshheading:1820928-Regression Analysis,
pubmed-meshheading:1820928-Software,
pubmed-meshheading:1820928-Theophylline
|
| pubmed:year |
1991
|
| pubmed:articleTitle |
Linear relationships in systems with non linear kinetics.
|
| pubmed:affiliation |
Laboratorio de Farmacodinamia, Facultad de Química, Montevideo, Uruguay.
|
| pubmed:publicationType |
Journal Article
|