A lysine at position 28 is switched out for an arginine, which leaves another lysine at position 26 free to be modified with a long fatty-acid/ethylene glyol-like chain, which improves the drugs half-life in the blood even more (by binding to serum albumin)
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Canadian researchers report consistent improvements in grip strength, pain reduction, and range of motion within the first 2-3 weeks of use
Lancet (London, England) 379:12561268 Stoppe C, Schlte G, Rossaint R, Coburn M, Graf B, Spillner J, Marx G, Rex S (2011) The intraoperative decrease of selenium is associated with the postoperative development of multiorgan dysfunction in cardiac surgical patients