This approach can be used when either one or both eyes are affected, providing there is sufficient limbal tissue available (1–2 mm2). A small sample of limbal cells is taken from a healthy part of the eye, and grown in a sterile laboratory to produce a sheet of cells sufficient for transplantation. Once transplanted, they multiply and regrow the corneal epithelium. The manufacturing process is designed to ensure implantation of the right number, size and quality of cells. CLET avoids some of the issues faced by other limbal transplantation procedures and does not pose a threat to the integrity of the donor eye. It also offers the possibility of re-grafting in case of failure of the first graft or need for a further graft. Types
There are three types of clonogenic keratinocytes involved in the generation of the corneal epithelium: holoclones, meroclones and paraclones. 1- Holoclones: as true stem cells, have the greatest growth potential, and give rise to               2-meroclones, which have a much lower proliferative capacity, but frequently divide. 3- Paraclones have even lower proliferative capacity. Both meroclones and paraclones are known as transient amplifying cells and their purpose is to form a stratified squamous epithelium. All three types of keratinocytes are present in the basal layer of the limbus, with holoclones in the least abundance (10%–15%).
Compensatory mechanism for metabolic alkalosis involve slowed breathing by the lungs to increase serum carbon dioxide, a condition leaning toward respiratory acidosis. As respiratory acidosis often accompanies the compensation for metabolic alkalosis, and vice versa, a delicate balance is created between these two conditions. See also
References
External links

IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "alkalosis". doi:10.1351/goldbook.A00221