A malignant fibrous histiocytoma with a predominance of myxoid areas that resemble primitive mesenchymal tissue. [myxo- + L. fibra, fiber, + G. sarx, flesh, + -Åma, tumor]. /myxoÂ·fiÂ·broÂ·sarÂ·coÂ·ma/ (-fiâ³bro-sahr-koÂ´mah) older term for the myxoid subtype of malignant fibrous histiocytoma.
1 Ammonium ion (NH4+), the most reduced natural specie of nitrogen, and the most biologically available in an oxygen-less environment;  Nitrate ion (NO3-), the most oxidized form of nitrogen and mostly usable in an aerobic environment;
Other Nitrogen Grades. Low-purity grades of nitrogen are composed of 90 up to 99.998 percent nitrogen. The common low-purity grade names include High Purity, Zero, Prepurified, Oxygen Free, Extra Dry and Industrial. The percentage of contaminates in these grades varies greatly. Oxygen Free grades contain less than 0.5 parts per million of oxygen.