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ESSENTIALS OF PHYSIOLOGY. 



ducing the condition of heat stroke. This occurs more readily if the 

 heat production is also increased, for example by muscular exercise, or if 

 the evaporation of sweat is checked by a humid atmosphere ; in these 

 circumstances the regulative mechanism may fail even though the 

 surrounding temperature is not very high. 



In fever the temperature of the body is raised, the regulative 

 mechanism again bringing about a balance between heat production 

 and heat loss, but at a higher level than in the normal person. Owing 

 to the raised temperature of the body metabolism is more rapid, the 

 breaking down of the tissues is increased, the output of nitrogen in the 

 urine rises, and a loss of weight generally takes place. 



