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.
Meronyms (parts of epithelial tissue): epithelial cell (one of the closely packed cells forming the epithelium). Hyponyms (each of the following is a kind of epithelial tissue): endothelium (an epithelium of mesoblastic origin; a thin layer of flattened cells that lines the inside of some body cavities).mesothelium (epithelium originating in the embryonic mesoderm; lines the primordial body cavity).eronyms (parts of epithelial tissue): epithelial cell (one of the closely packed cells forming the epithelium). Hyponyms (each of the following is a kind of epithelial tissue): endothelium (an epithelium of mesoblastic origin; a thin layer of flattened cells that lines the inside of some body cavities).