人的正常体温升高,叫做发热。据医生说,发热是人的身体向引起疾病的细菌和病毒进行斗争的迹象。不过医学研究人员仍在对发热及其重要性进行研究。人的大脑控制体温的部位叫下丘脑。天气寒冷时,皮肤中的神经就会向大脑发出信号,让身体储存热量;当天气炎热时,大脑就会“通知”身体发出热量。用这种方法,下丘脑使人的身体正常温度保持在37℃左右。当人们的体温超过这个温度时,就是发热。细菌和病毒引起人体的防病系统释放出一种叫做热原的物质,热原这一词的含意是致热物。这些物质对下丘脑中的温度控制细胞产生影响,使下丘脑作出 The normal human body temperature, called fever. According to doctors, fever is a sign of the body’s fight against the bacteria and viruses that cause the disease. However, medical researchers are still studying the importance of fever. Human brain temperature control part of the body called the hypothalamus. When the weather is cold, the nerves in the skin send a signal to the brain that the body stores calories; when the weather is hot, the brain “notifies” the body of heat. In this way, the hypothalamus keeps the body’s normal temperature around 37 ° C. When people’s body temperature exceeds this temperature, it is fever. Bacteria and viruses cause the body’s anti-disease system to release a substance called pyrogen, which means pyrogen. These substances have an effect on the temperature-controlled cells in the hypothalamus, making the hypothalamus