BIOLOGY IN HUMAN AFFAIRS 



hot applications, by applying substances which break 

 down the cells, by rubbing, and by other manipulations 

 with which almost everyone is familiar. 



If there is a deficiency of calcium in the blood, this 

 will delay the clotting. However, calcium itself is associ- 

 ated with many other conditions of health. Of these more 

 will be said later. 



The white blood cells are certainly as significant as 

 the red blood cells for human health and life. When inflam- 

 mation occurs anywhere in the human body, the blood 

 brings enormous numbers of white blood cells to the spot. 

 They come there and remove the degenerated or broken 

 down material. They are of many varieties. In times of 

 infection, for instance in appendicitis, the number of white 

 blood cells will be raised promptly to 15,000 or even to 

 50,000 as compared with the 5,000 to 7,000 that is normal. 

 One variety will be increased greatly in percentage as 

 compared with the other varieties. This variety is called 

 the polymorphonuclear white blood cell because it is a 

 white cell with many nuclei. Whereas normally it composes 

 from 55 to 65 per cent of all the white blood cells, the 

 number may increase so rapidly in time of infection that 

 this form will constitute 75 to 90 per cent. Another of 

 the forms is mononuclear. In many diseases this form is 

 greatly reduced, and in other diseases increased. A third 

 form of white blood cell, called eosinophile because it 

 stains readily with eosin, is increased in number in some 

 diseases — unquestionably in infestation with the pork 

 worm known as trichina. 



The medical profession and workers in research labora- 

 tories throughout the world are spending vast amounts 

 of time and energy to identify the various forms of white 

 blood cells and to discover their exact significance in 

 different kinds of diseases. Experts on the blood can tell 

 even now whether a person is suffering from one type of 



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