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\name{Theoph}\docType{data}\alias{Theoph}\title{Pharmacokinetics of theophylline}\description{The \code{Theoph} data frame has 132 rows and 5 columns of data froman experiment on the pharmacokinetics of theophylline.}\usage{Theoph}\format{This data frame contains the following columns:\describe{\item{Subject}{a factor with levels \code{A}, \dots, \code{L} identifying thesubject on whom the observation was made.}\item{Wt}{weight of the subject (kg).}\item{Dose}{dose of theophylline administered orally to the subject (mg/kg).}\item{Time}{time since drug administration when the sample was drawn (hr).}\item{conc}{theophylline concentration in the sample (mg/L).}}}\details{Boeckmann, Sheiner and Beal (1994) report data from a study byDr. Robert Upton of the kinetics of the anti-asthmatic drugtheophylline. Twelve subjects were given oral doses of theophyllinethen serum concentrations were measured at 11 time points over thenext 25 hours.These data are analyzed in Davidian and Giltinan (1995) and Pinheiroand Bates (2000) using a two-compartment open pharmacokinetic model,for which a self-starting model function, \code{SSfol}, is available.}\source{Boeckmann, A. J., Sheiner, L. B. and Beal, S. L. (1994), \emph{NONMEMUsers Guide: Part V}, NONMEM Project Group, University ofCalifornia, San Francisco.Davidian, M. and Giltinan, D. M. (1995) \emph{Nonlinear Models forRepeated Measurement Data}, Chapman & Hall (section 5.5, p. 145 andsection 6.6, p. 176)Pinheiro, J. C. and Bates, D. M. (2000) \emph{Mixed-effects Models inS and S-PLUS}, Springer (Appendix A.29)}\seealso{\code{\link{SSfol}}}\examples{xyplot(conc ~ Time | Subject, Theoph, aspect = 'xy',xlab = "Time since drug administration (hr)",ylab = "Theophylline concentration (mg/L)")Theoph.4 <- subset(Theoph, Subject == 4)fm1 <- nls(conc ~ SSfol(Dose, Time, lKe, lKa, lCl),data = Theoph.4)summary(fm1)plot(conc ~ Time, data = Theoph.4,xlab = "Time since drug administration (hr)",ylab = "Theophylline concentration (mg/L)",main = "Observed concentrations and fitted model",sub = "Theophylline data - Subject 4 only",las = 1, col = 4)xvals <- seq(0, par("usr")[2], len = 55)lines(xvals, predict(fm1, newdata = list(Time = xvals)),col = 4)}\keyword{datasets}