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Papageorgiou et al., 2016)

The current study did not find an APOE genotype effect on the cerebrovascular uptake of L-carnitine, its metabolites, or FAs at 26 weeks of age

That is a small volume, easy to measure accurately even for beginners

Similarly, an animal model of diabetes-induced HF showed altered expression levels of copper transporter proteins and disturbed copper metabolism in rat cardiomyocytes (67)
