Blood urea nitrogen (BUN) test. Overview. A common blood test, the blood urea nitrogen (BUN) test reveals important information about how well your kidneys and liver are working. A BUN test measures the amount of urea nitrogen that's in your blood. 1  Your liver produces ammonia â which contains nitrogen â after it breaks down proteins used by your body's cells.  The nitrogen combines with other elements, such as carbon, hydrogen and oxygen, to form urea, which is a chemical waste product.
Shortly after the Turner Turnpike was built in 1953, the Oklahoma Turnpike Authority proposed other toll roads including one to be built from Oklahoma City north to the Kansas border near Braman to tie in with the southern terminus of the Kansas Turnpike at the state line.
Designed by Ole Singstad, the tunnel was funded by the New Deal's Public Works Administration. Construction began on the first tube in March 1934. It opened to traffic on December 22, 1937, charging $0.50 per passenger car, equal to $8.2 today. The cost of construction was $85 million, equal to $1.5 billion today.