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.
The lungs are a pair of spongy, air-filled organs located on either side of the chest (thorax). The trachea (windpipe) conducts inhaled air into the lungs through its tubular branches, called bronchi. The bronchi then divide into smaller and smaller branches (bronchioles), finally becoming microscopic.etween the alveoli is a thin layer of cells called the interstitium, which contains blood vessels and cells that help support the alveoli. The lungs are covered by a thin tissue layer called the pleura. The same kind of thin tissue lines the inside of the chest cavity -- also called pleura.