Fissure filling is a treatment that improves the apparent clarity of a gemstone by removing air and replacing it with a substance that has a refractive index similar to the host material. Many different substances may be used to fill fissures: oils, resins, waxes, glass, and various polymers, to name a few.
Cerebral autoregulation is a process in mammals, which aims to maintain adequate and stable cerebral blood flow.hile most systems of the body show some degree of autoregulation, the brain is very sensitive to over-and underperfusion. Cerebral autoregulation plays an important role in maintaining an appropriate blood flow to that region.
This is a potentially lethal complication of severe hypertension and may be seen in association with a number of hypertensive emergencies. When markedly elevated BP exceeds the autoregulatory ability of the brain to maintain constant cerebral perfusion, the resultant diffuse cerebral edema can lead to progressive neurologic dysfunction.