High body temperature can be divided into two constitutions: excess heat and deficiency cold.
You can understand the meaning of body temperature:
The temperature of human body is relatively constant. Normal people's body temperature fluctuates slightly within 24 hours, and generally the difference is not more than 65438 0 degrees. Physiologically, the body shape is slightly lower in the morning and slightly higher in the afternoon. After exercise, after eating, before menstruation or before pregnancy, the body temperature of women is slightly higher, while that of the elderly is lower. If the body temperature is higher than normal, it is called fever, 37.5 ~ 38 degrees is low fever, 38 ~ 39 degrees is moderate fever, 39 ~ 40 degrees is high fever, and above 40 degrees is ultra-high fever. Relatively constant human body temperature is one of the important conditions for maintaining normal human life activities. For example, when the body temperature is higher than 4 1 degree or lower than 25 degrees, it will seriously affect the functional activities of various systems (especially the nervous system) and even endanger life. The heat production and heat dissipation of human body are regulated by nerve center, and many diseases will cause problems in the normal regulation of body temperature and make it change. It is of great significance to check the patient's temperature and observe its changes in clinic for diagnosing diseases or judging the prognosis of some diseases.
First, the significance of relatively stable body temperature
The temperature of the earth's surface is constantly changing all year round, and the temperature in different regions is also very different. (The difference between the highest and lowest temperatures can be 150℃. Even in many temperate regions, the temperature difference between winter and summer is often above 60℃. ) Humans can live and work in extremely harsh climatic conditions and maintain a relatively constant body temperature, that is, around 37℃, because they have a perfect body temperature regulation mechanism and can take measures to prevent cold and keep warm.
The function of warm-blooded animals to keep their body temperature constant is produced in this process. Lower animals (invertebrates and lower vertebrates, reptiles, amphibians and fish) have no perfect body temperature regulation mechanism, and their body temperature changes with the environmental temperature or the amount of solar radiation heat, so they are called thermogenic animals. Thermophilic animals can only grow, reproduce and carry out normal activities within their suitable temperature range. When the ambient temperature is too high or too low, they will hide or sleep. The thermoregulation mechanism of birds, mammals, especially humans has evolved very well, and it can keep the body temperature relatively stable at different environmental temperatures, so it is called warm-blooded animals. Constant body temperature keeps the functional activities of various organs and systems in a high level, thus enhancing the body's ability to adapt to the environment.
Second, measure your temperature.
(1) body surface temperature and deep temperature
Usually, a special mercury thermometer is used to measure body temperature. Thermocouples, thermistors and thermometers can also be used.
Generally speaking, a person's body temperature is 37℃, which refers to the temperature inside the body. In fact, careful study shows that the temperature of different parts of the body is different, which can be divided into two parts: deep temperature and body surface temperature. The deep part and body surface mentioned here have no strict anatomical significance, but only refer to the division of functional models.
1. Deep temperature The deep temperature of the human body is relatively stable and uniform. However, due to different metabolic levels, the temperature of each viscera is slightly different. The liver temperature can reach up to 38℃. The brain generates more heat and the temperature is close to 38℃. The temperature of kidney, pancreas and duodenum is slightly lower. Due to the continuous circulation of blood, the temperature of deep organs tends to be consistent. So theoretically, body temperature refers to the blood temperature in the deep layer of the body, which can represent the average temperature of the internal organs of the body.
2. The body surface temperature is lower than the deep temperature, and there is an obvious temperature gradient from the inside out. The body surface has a certain thickness, which can play the role of heat insulation layer for body temperature regulation and maintain the relative stability of deep body temperature through it.
The outermost layer of the body surface, that is, the skin surface, is called skin temperature. The skin temperature of different parts of the body varies greatly. When the ambient temperature is 23℃, the forehead skin temperature is 33 ~ 34℃, the trunk is 32℃, the hands are 30℃ and the feet are 27℃. In the cold environment, with the temperature drop, the skin temperature of limbs (hands and feet) drops obviously, while the skin temperature of head changes relatively little. Skin is rich in blood vessels, and any factor that can affect the vasodilation of skin can change the temperature of skin.
(2) The body temperature of the test site and its normal value
Because the temperature of deep blood in the body is difficult to measure, in clinical examination and experimental research, for convenience, the temperature of armpit, mouth or rectum is usually measured to represent body temperature. Generally, the rectal temperature is the highest, close to the deep body temperature, about 37.5℃. The oral temperature is about 0.5℃ lower than the rectal temperature, and the rectal temperature is about 37.0℃. Axillary temperature is about 0.4℃ lower than oral temperature. When reporting the body temperature, you should point out the location of the measurement.
Third, the physiological changes of body temperature.
Although the temperature deep in the body is relatively constant, it is not fixed. Under normal physiological conditions, body temperature can change to some extent with day and night, age, sex, environmental temperature, mental and physical activities and other conditions.
(1) Circadian rhythm
Human body temperature has a day and night cycle. During the day, the body temperature is the lowest at 2-6 am, and it starts to rise after dawn, maintaining at a high level all day and reaching the peak of the day at 6 pm (Figure 9- 1). This physiological phenomenon, which takes day and night (24 hours) as the cycle, with repeated peaks and valleys, is called circadian rhythm. No matter where people live on the earth, their body temperature fluctuates day and night. On the surface, the reason for the increase of body temperature during the day is due to more activity, high metabolic rate and increased heat production. Actually, it's not. People who lie in bed all day or stay up all night have the same periodic change in body temperature. Experiments show that the circadian rhythm still exists when the subjects are placed in the deep basement without any time marks for a long time. But at this time, the day and night cycle is slightly longer than 24 hours, which is called self-excitation cycle. If the subject returns to the ground and is affected by synchronous factors such as light, his physiological cycle will gradually return to its original state and keep pace with the earth's rotation cycle. It is generally believed that the generation of this rhythm is endogenous and controlled by the pacing point of circadian rhythm (also known as biological clock). Experiments show that the suprachiasmatic nucleus of hypothalamus is probably the control center of biological rhythm.
(2) Gender
The average body temperature of women is about 0.3℃ higher than that of men. In addition to gender differences, women's body temperature also has the characteristics of monthly rhythm. The body temperature level of adult women fluctuates with the menstrual cycle. As shown in Figure 9-2. The measurement of basal body temperature (I didn't get up in the morning to measure the oral temperature) showed that my body temperature was higher before menstruation. At the same time of menstrual cramps, my body temperature dropped by about 0.2 ~ 0.3℃, then dropped by 0.2℃ during ovulation, and then suddenly increased. Clinically, whether the subjects ovulate and the date of ovulation can be detected by continuously measuring the basal body temperature. The periodic fluctuation of female body temperature is consistent with the level of progesterone and its metabolites in blood. This monthly cycle change may also be under the control of the biological clock.
(3) Age
The thermoregulation mechanism of newborn babies and young children has not been fully developed, so nursing and heat preservation should be strengthened. A few months after birth, with the improvement of the nervous system and the establishment of the law of activity and rest, the circadian rhythm of body temperature gradually formed. The metabolic activity of the elderly is weakened, the body temperature is lower than that of the young and middle-aged people, and the compensation ability for the temperature change of the external environment is reduced. They can't stand the stimulation of drastic changes in the external environment, and they should also pay attention to heat preservation and heat dissipation in time.
Physical activity and emotions
Muscle activity can significantly increase heat production, leading to an increase in body temperature. Mental stress and emotional excitement can also increase body temperature. In some cases, the body temperature can rise by about 2℃. During anesthesia, the body temperature drops, so pay attention to heat preservation.
In short: the body temperature of men and women, adults and children, before and after pregnancy, before and after exercise is different, that is, the same person is different in the morning and evening and in different seasons.
If you don't feel sick, there should be no big problem. If you are worried, it is safer to go to the hospital to consult a doctor.