Serum (blood) toxic response. Blood is centrifuged to remove cellular components. Anti-coagulated blood yields plasma containing fibrinogen and clotting factors. Coagulated blood (clotted blood) yields serum without fibrinogen, although some clotting factors remain. Serum is an essential factor for the self-renewal of embryonic stem cells in combination with the cytokine leukemia inhibitory factor. The serum of convalescent patients successfully recovering (or already recovered) from an infectious disease can be used as a biopharmaceutical in the treatment of other people with that disease, because the antibodies generated by the successful recovery are potent fighters of the pathogen. Such "convalescent serum" (antiserum) is a
Blood, toil, tears, and sweat Blood, toil, tears, and sweat The phrase "blood, toil, tears and sweat" became famous in a speech given by Winston Churchill to the House of Commons of the Parliament of the United Kingdom on 13 May 1940. This was Churchill's first speech on 13 May 1940 to the House of Commons after having been offered the King's commission the previous Friday, to become Prime Minister of the United Kingdom in the first year of World War II. Churchill had replaced Neville Chamberlain on 10 May, and in this speech he asked the House to declare its confidence in his Government.