AstraZeneca itself is building an arsenal of anti-cancer pills known as tyrosine kinase inhibitors.

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Tyrosine and phenylalanine are related and have been used as alternative remedies for depression.

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By 1999 Zeneca had devised a drug, Iressa, that interrupted the pathways between EGF and tyrosine kinase.

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One mechanism of oxidative damage is the nitration of tyrosine residues in proteins, mediated by peroxynitrite breakdown.

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When EGF docks on a receptor, it signals to an enzyme called tyrosine kinase to regulate cell growth.

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Although carbonyl formation is a major oxidative modification induced by peroxynitrite, nitration of tyrosine residues is an indicator of peroxynitrite involvement.

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L-Tyrosine: L-Tyrosine is an amino acid found in high protein foods.

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By patching in a plant gene, they have created a mutant strain that can make an enzyme which converts a natural amino acid called tyrosine into one of the synthetic forms.

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