1 All Physician Training licenses expire on August 31, 2015, are good for three years, and can only renew once (for a total of six years). 2  All Physician Assistant licenses expire on January 31 of even-numbered years.  All Anesthesiologist Assistant licenses expire on January 31 of even-numbered years.
The epidermis is the uppermost or epithelial layer of the skin. It acts as a physical barrier, preventing loss of water from the body, and preventing entry of substances and organisms into the body. Its thickness varies according to body site. The epidermis consists of stratified squamous epithelium.
Squamous epithelial cells are a sub-type of epithelial cells (cells which line glands and the inner and outer surfaces of the body). These cells are characterized as being ver â¦ y thin and flat epithelial cells and populate organs such as the skin and esophagus.pithelial cells are the individual cells of an epithelium, which is a layer of cells forming the surface of a structure or an inner lining. For example, there is an epithel â¦ ium lining the alimentary canal (gut), and another lining the alveoli of the lungs. Human skin also consists of epithelial cells.