1 In 1990, Barack Obama was elected as the first black president of the Harvard Law Review. 2  Obama, who graduated from HLS in 1991, would later represent Illinois in the U.S Senate, and in 2008 would become the 44 th President of the United States, and the first African-American president.
Most cancers in the lung are carcinomas-cancers of epithelial cells. The top pair of images shows the normal epithelium of the bronchi. This photomicrograph is greatly enlarged. The next three pairs of images show three successive stages of abnormal changes in the bronchial epithelium commonly found in smokers.
Transitional epithelium is a specialized form of stratified skin tissue. It is often called urothelial epithelium because the lining of the urinary tract is the most common place to find it. Transitional epithelium is very different from other types of epithelium because its cells are able to change shape to increase the amount of stretching the tissue can withstand. This ability to change shape is the reason it is referred to as transitional as the cells transition from one shape to another.