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structed from five logKi values (Tables 2 and 3) and
which contains one parameter (out of a possible five:
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a model containing two parameters has an Fmax value
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Acknowledgments
We thank Dr. Jan du Preez and the staff of the Analyt-
ical Technology Laboratory as well as Dr. Douw van
der Nest and the staff of the Experimental Animal Facil-
ity, North-West University, for their support. The NMR
´
and MS spectra were recorded by Mr. Andre Joubert
and Dr. Louis Fourie of the SASOL Centre for Chemis-
try, North-West University. Assistance with the statisti-
cal analysis was provided by Dr. Suria Ellis of the
Statistical Consultation Service, North-West University.
This work was supported by grants from the National
Research Foundation and the Medical Research Coun-
cil, South Africa.
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