PT141 is a copy of a hormone which has an effect on the nervous system called alpha-melanocyte-stimulating hormone.

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Some type of parabens are known to disrupt hormone function, an effect that is linked to increased risk of breast cancer and reproductive toxicity, but they are just one type of hormone disrupting chemicals found in cosmetics.

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Isoflavone is a major class of phytoestrogens, naturally occurring chemicals that mimic the effect of the human hormone oestrogen.

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Pegvisomant (Somavert) blocks the effect of excess growth hormone on the body.

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And while EPO's effect is long-lasting, the hormone itself rapidly disappears from the body.

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The gene they chose is involved in the synthesis of a hormone called gibberellin and, once again, a side-effect of the alteration was to cause the trees to grow faster.

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When I was a medical reviewer at the FDA in the 1980s, a completely unexpected side effect occurred in the clinical testing of a new formulation of human growth hormone synthesized in bacteria.

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The researchers say it might be possible to use the hormone to develop new drugs to combat impaired learning and memory, but warn that weight gain could be a side effect.

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