support for other experiments, like radiolabeling + urine analysis

[egonw]

This is the approach taken in this paper for aniline:

Kao, J., Faulkner, J., Bridges, J.W.
Metabolism of aniline in rats, pigs and sheep
Drug Metabolism and Disposition
Volume 6, Issue 5, 1978, Pages 549-555

At this moment I cannot enter the metabolites found in this paper.

(From a CYP modeling perspective that makes perfect sense, but allowing such more general metabolism information allows recording of a lot more data...)

[vedina]

be able to specify species
@olas should we consider extending beyound human data ?