Chemical and physical evidence for

The chemical and physical evidence for the presence of lignin in the material deposited at wound margins is supported by biochemical studies on the enzymes involved in phenylpropanoid metabolism. Thus, the extractable activities of phenylalanine ammonia-lyase, tyrosine ammonia-lyase, cinnamate-4-hydroxylase, caffeic acid O-methyltransferase,... 

This structure does not, however, fully explain the chemical and physical evidence for the presence of aluminum in four-coordination. In this proposed structure all of the aluminum... 

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