Ligneous relates to which natural substance?
Ligneous conjunctivitis Ligneous conjunctivitis Ligneous conjunctivitis is a rare form of chronic conjunctivitis characterized by recurrent, fibrin-rich pseudomembranous lesions of wood-like consistency that develop mainly on the underside of the eyelid (tarsal conjunctiva). It is generally a systemic disease which may involve the periodontal tissue, the upper and lower respiratory tract, kidneys, middle ear, and female genitalia. It can be sight-threatening, and death can occasionally occur from pulmonary involvement. It has been speculated that ligneous conjunctivitis may be a manifestation of IgG4-related disease (IgG4-RD) involving the conjunctiva. Histopathological findings from affected humans indicate that wound healing is impaired due to a deficiency
Amount of substance are atoms in of the isotope carbon-12. This number is called the Avogadro number and has the value It is the numerical value of the Avogadro constant, which has the unit mol, and relates the molar mass of an amount of substance to its mass. Therefore, the amount of substance of a sample is calculated as the sample mass divided by the molar mass of the substance. Amount of substance appears in thermodynamic relations such as the ideal gas law, and in stoichiometric relations between reacting molecules as in the law of multiple proportions. Another unit of amount of substance