动物实验 z-bo 2020-09-10 490

　　Generally, it is safe to treat mice for 2 hours in a stable, strong magnetic field of 3.5-23 Tesla. 23 Tesla has a certain effect on food intake and weight gain, but less than 21.9 Tesla has no effect. This photo is provided by the Strong Magnetic Field Science Center of the Chinese Academy of Sciences.

　　A group of researchers at the Center for High Magnetic Field Science of the Chinese Academy of Sciences today (June 5) Zhang Xin used a large scientific instrument with a strong magnetic field to reach the level of 20 Tesla in a steady state. Announced a new breakthrough in the biosafety of high magnetic fields, and for the first time reported the impact of a strong magnetic field exceeding 20 Tesla on key physiological and biochemical indicators of normal mice. Related results have been published online in the international neuroimaging journal "euroimage" (neuroimage).

　　team members conducted a small experiment in the early stage to detect the effect of a strong magnetic field of 3.7-24.5 Tesla on tumor-bearing mice. The treatment lasted 9 hours and was found to have a certain inhibitory effect on tumor growth. Most of the physiological and biochemical indicators of mice are not abnormal, but their livers are affected by strong magnetic fields.

　　According to previous experiments, the team members reduced the magnetic field strength and reduced the processing time of the magnetic field. Under the magnetic field strength of 3.5-23 Tesla, 112 normal mice were treated for 2 hours, and then kept normally for 3 weeks. Comprehensively and systematically test biological safety. Through the pathological part, regular blood tests and blood biochemical analysis, this treatment method can treat the main organs of mice (heart, liver, spleen, lungs, kidneys), blood, and conventional indicators of liver and kidney function. It turns out that it is not affected. , The main physiological indicators such as lipid metabolism and ion concentration cause obvious damage. In the 23 Tesla treatment group, there was a certain effect on food intake and weight gain, but there was no significant effect in a strong magnetic field lower than 21.9 Tesla.

　　" Chang Singh said: "This research is of great significance for determining the biological safety limits of strong magnetic fields and for providing active guidance for exploring the application of strong magnetic fields in the fields of medicine and equipment. it is. With the development of science and technology, the constant magnetic field strength used in hospital MRI scanners is usually increased from the initial 0.5 Tesla to 1.5 Tesla or 3 Tesla to improve tissue resolution and image processing capabilities. done. Tesla. However, due to the relative shortage of equipment with a strong magnetic field exceeding 10 Tesla, there are currently few studies on the biological safety of a strong magnetic field in a steady state, and the safety of a strong magnetic field exceeding 20 Tesla can be carried out. the study. It is close to blank. Therefore, studying the biological safety of steady-state strong magnetic fields has important scientific and practical significance for the development and clinical application of high-field MRI scanners.