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solving an integral for pharmacokinetics work
Hi,
Pharmacokinetics: mathematically characterizing how a drug enters and leaves the body
In pharmacokinetics experiments the influence of the stomach is ignored in most data analyses, which is not appropriate. Stomach emptying can be described with the equation (in which t=time):
Plateau×(1-e^(-Ks × t))^ß (Ks=rate, beta =lag phase)
Subsequently, the absorption kinetics of a test component can be described with the equation:
Plateau ×(Ka× (Exp^(-Ke × t)-Exp^(-Ka × t)))/(Ka-Ke) (Ka=absorption rate, Ke=elimination rate, Plateau is cummulative absorption)
Combining both gives:
∫ Plateau×(1-e^(-Ks × t))^ß * Plateau ×(Ka× (Exp^(-Ke × t)-Exp^(-Ka × t)))/(Ka-Ke)
Does anybody know how to solve such an equation in JMP, or is someone smart enough to integrate them (I am not)? I can only solve it in Excel, but then I don't get statistics.
Happy to include you as a co-author in a publication on the topic if we end with publishable outcomes.
thanks
Theo
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Re: solving an integral for pharmacokinetics work
There are many sirtes on the internet that will solve derivatives and integrals for you. See this link for one of my favorites:
http://www.integral-calculator.com/
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Re: solving an integral for pharmacokinetics work
Hi Steven,
Thanks for pointing this out to me; learning every day. I have tried the link you supplied, and this site can't find an answer, same answer I got from a couple of professors in mathematics.
Theo
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Re: solving an integral for pharmacokinetics work
came across the wolfram site, and this one did yield an integral. Something to try tonight ;-)
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Re: solving an integral for pharmacokinetics work
Wolfram Alpha...maybe?
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Re: solving an integral for pharmacokinetics work
I think you could use JSL to solve the problem
pl=1;
ka=1;
ke=.5;
pk=expr(pl*(ka*(exp(-ke*t)-exp(-ka*t)))/(ka-ke));
integrate(pk, t, 0, 12);