Lead flashing was commonly used on chimneys, around other roof penetrations such as vent pipes, and roof junctions, such as valleys. It is still used for this, but is less common because of its cost, and the availability of alternatives. Modern alternatives: pvc, butyl rubber etc. are often less durable.
Granulocytes, specifically neutrophils, help the body fight bacterial infections. The number of granulocytes in the body usually increases when there is a serious infection. People with a lower number of granulocytes are more likely to develop bad infections more often.
Neutrophils, Phagocytosis, and Chemotaxis. In any case, there are three sub-species, so to speak, of granulocytes, or spotted white horses, in your body. The first is called a neutrophil. These are granulocytes involved in fighting off pathogens, such as bacteria and fungi, and are the most abundant leukocyte in mammals. These are the cells that are responsible for that icky yellowish pus you may see seeping out of infected wounds.