Endocrine disruptor occur from low-dose exposure to exogenous hormones or hormonally active chemicals such as bisphenol A. These chemical can bind to receptors for other hormonally mediated processes. Furthermore, since endogenous hormones are already present in the body in biologically active concentrations, additional exposure to relatively small amounts of exogenous hormonally active substances can disrupt the proper functioning of the body's endocrine system. Thus, an endocrine disruptor can elicit adverse effects at much lower doses than a toxicity, acting through a different mechanism. The timing of exposure is also critical. Most critical stages of development occur in utero, where the fertilized egg
Endocrine surgery Endocrine surgery Endocrine surgery is a surgical sub-speciality focusing on surgery of the endocrine glands, including the thyroid gland, the parathyroid glands, the adrenal glands, glands of the endocrine pancreas, and some neuroendocrine glands. Surgery of the thyroid gland constitutes the bulk of endocrine surgical procedures worldwide. This may be done for a variety of conditions, ranging from benign multinodular goiter to thyroid cancer.In the United Kingdom it was developed as a separate speciality from general surgery at the Royal Postgraduate Medical School by Dick Welbourne and John Lynn. Operations involve removal of the thyroid gland (thyroidectomy) either as a