The parathyroids produce a hormone called parathyroid hormone (PTH). PTHPTH-parathyroid hormone raises the blood calcium level by: 1  breaking down the bone (where most of the body's calcium is stored) and causing calcium release. 2  increasing the body's ability to absorb calcium from food.THPTH-parathyroid hormone raises the blood calcium level by: 1  breaking down the bone (where most of the body's calcium is stored) and causing calcium release. 2  increasing the body's ability to absorb calcium from food.
DN = Diameter Nominal. The term Diameter Nominal refers to the internal diameter of a pipe. Together with the nominal pressure rating and the materials class, all dimensions of a piping line, e. g. flange dimensions, are defined by indicating the nominal diameter. Steel is often not specified, but assumed as material.
Applying the nominal size across domains requires understanding of the size systems in both areas; for example, someone wishing to select a drill bit to clear a  1â4 -inch screw may consult tables to show the proper drill bit size.or example both 1â2 inch and 15 millimetres (0.59 in) copper pipe is actually the same pipe which has a nominal internal diameter of 1â2 an inch and a nominal external diameter of 15 millimetres (diameter is always internal in the imperial measurement system and always external in metric).