In a direct Coombs' test a special antibody is added to a sample of blood. This test checks whether there are antibodies already bound to the surface of the red blood cell. If the test is positive the antibodies that are added bind to the antibodies on the surface of the cell.
The River Hull is a navigable river in the East Riding of Yorkshire in the north of England. It rises from a series of springs to the west of Driffield, and enters the Humber estuary at Kingston upon Hull.
Once the river reaches the outskirts of Hull, its course is marked by a series of bridges, most of which open to allow boats to pass. There are swing bridges, lift bridges and bascule bridges, and the river becomes part of the Port of Hull.