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1.
Most of the published studies on magnetic field action on biological systems have examined reactions in animals, while a smaller number of studies have reported magnetic field effects in plants. The effects of static magnetic field on the activity of several key enzymes in plant metabolism, such as malate dehydrogenase, succinate oxidase, succinate dehydrogenase, and cytochrome oxidase in young wheat seedlings, have been investigated in this study. It appears that the observed changes in enzyme activity could be considered to be a result of the influence of the magnetic field on the reactivity of these enzymes, including effects on metal cations that regulate enzyme activity. The results support the idea of the existence of “biological windows,” particularly with respect to exposure time.  相似文献   

2.
We investigated the effect of a static magnetic field (0.1 T) on various electrical parameters of goat eye lens using a computer-aided AC impedance system (EG&G 278) at 30°C. Results of measurements on voltage-current characteristics showed that the static magnetic field alters the current flow in the tissue. The complex impedance plane drawn between real (Z') and imaginary (Z) parts in the form of a Cole-Cole plot demonstrates that under magnetic field, the distribution factor a decreases from 0.3 ± 0.006 to 0.24 ± 0.005 and the extracellular resistance (Re) increases from 52 ± 1.3 to 60 ± 1.5 K ohms in the lens tissue. An attempt has been made to explain the interactive behavior of the magnetic field with the electrical changes in the lens.  相似文献   

3.
4.
The interaction of static magnetic fields (SMFs) with living organisms is a rapidly growing field of investigation. The magnetic fields (MFs) effect observed with radical pair recombination is one of the well-known mechanisms by which MFs interact with biological systems. SMF influenced cellular antioxidant defense mechanisms by affecting antioxidant enzymes such as superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT). However, there were insufficient reports about the effects of SMF on macro and trace elements in serum, and the results were contradictory until now. In the current study, 12 rats were divided into two groups, namely as control and exposure group (128 mT and 1 h/day during five consecutive days). The macro and trace element concentrations in serum were examined. No significant difference was observed in the sodium (Na), potassium (K), calcium (Ca), phosphorus (P), and selenium (Se) levels in rat compared to control. By contrast, exposure to SMF showed an increase in the zinc (Zn) level and a decrease in iron (Fe) concentration. Under our experimental conditions, SMF exposure cannot affect the plasma levels of macroelements, while it can disrupt Zn and Fe concentrations in rat.  相似文献   

5.
Effect of Magnetic Field on Chick Morphogenesis   总被引:1,自引:0,他引:1  
It is well known that development of organisms, as well as normal functioning of different systems, is to a large extent affected by environmental factors. To study the effect of magnetic field on the chick morphogenesis, fresh fertilized eggs of White Leghorn were incubated to the definitive primitive streak stage [Hamburger-Hamilton (H.H.) stage 4]. The embryos were mounted on a watch glass using News in vitro culturing technique and then exposed to a homogeneous magnetic field of 5000 ± 200 Oe for 1 h. The controls were maintained simultaneously without the magnetic field. The experimental and control embryos were further incubated for 24 h so as to obtain the H.H. stage 12 in the controls. It was observed that experimental embryos were considerably retarded, as evidenced by shortening of the embryonic long axis and by other malformations. In 14 out of the 25 experimental embryos, the brain was poorly developed with open neural tube. In 18 of the 25 experimental embryos, the somites were diffused, and in 12 of the 25 experimental embryos, the heart was developed with slight displacement. All the controls developed normal to H.H. stage 12. Histological observations of the neural structures in the sectioned experimental embryos show increase in the number of dividing cells and their dispersed distribution throughout the neuroepithelium. The malformations recorded are attributed to the environmental stress effect caused by the magnetic field as manifested by its effect on mitotic activity, interkinetic nuclear migration in neuroepithelium and cell locomotion in general.  相似文献   

6.
目的 :探讨磁场作用对小鼠抗应激能力的影响。方法 :对磁场处理 30分钟和 1 5分钟的两组实验组与非磁场处理的正常对照组进行游泳耐疲劳运动时间的比较。结果 :游泳耐疲劳运动实验表明 30分钟磁场处理组与正常对照组比较 ,动物游泳耐疲劳运动时间延长 ,且具有显著性差异 (p <0 .0 5 ) ;1 5分钟磁场处理组与正常对照组比较 ,动物游泳耐疲劳运动时间无明显差异 (p >0 .0 5 ) ;30分钟磁场处理组与 1 5分钟磁场处理组比较 ,动物游泳耐疲劳运动时间延长 ,且具有显著性差异 (p <0 .0 5 )。结论 :在一段时间( 30天 )内 ,每天给予小鼠 30分钟的磁场处理明显提高了小鼠的抗应激能力 ,而磁场处理 1 5分钟对小鼠的抗应激能力不产生影响。  相似文献   

7.
The aim of the present work is to evaluate the effect of caffeine, the world’s most popular psychoactive drug, on the electric activity of the rat’s brain that exposed to extremely low-frequency magnetic field (ELF-MF), during 15 days. The obtained results showed that administration of caffeine in a group of rats by dose of 10 mg/kg (equivalent to human daily consumption) caused a reduction in the mean power amplitude of electroencephalogram (EEG) trace for almost all frequency bands especially α (8–12 Hz). It was observed that the influence of caffeine was more evident in motor cortex than in visual cortex. While the exposure of another group to ELF-MF of intensity 0.2 mT during the same period caused an enhancement in the mean power amplitude of most EEG frequency bands; this was more observed in the right hemisphere of the brain than that of the left hemisphere. The administration of caffeine while rats were exposed to ELF-MF, led, after 5 days of exposure, to a great increase in the mean power amplitude of α band at all places of recording electrodes. It may be concluded that caffeine administration was more effective in reducing the hazardous of ELF-MF in motor cortex than in visual cortex.  相似文献   

8.
刘占才  牛景彦 《四川动物》2012,31(2):245-248
研究了暴露在不同高效氯氰菊酯浓度下的草鱼Ctenopharyngodon idella肝胰脏和肾脏溶菌酶(LSZ)的活性变化.实验中高效氯氰菊酯浓度设5组,分别为0 μg/L、0.5μg/L、1.0 μg/L、3.0μg/L和5.0 μg/L,每组分别于1d、5d和12 d取样,测定肝胰脏和肾脏溶菌酶活性.结果显示,肝胰脏LSZ活性在暴露1d、5d、12 d时,各处理组均显著下降(P <0.05,P <0.01).肾脏LSZ活性在暴露1d、5d时,0.5μg/L、1.0 μg/L和3.0 μg/L组显著上升(P<0.05,P<0.01),5.0 μg/L组显著下降(P<0.01);暴露12d时,0.5μg/L、1.0 μg/L组显著上升(P<0.05),3.0μg/L和5.0 μg/L组显著下降(P<0.05,P<0.01).表明高效氯氰菊酯对草鱼肝胰脏和肾脏具有明显的毒害作用.  相似文献   

9.
The effect of inhomogeneous static magnetic field (SMF)-exposure on the production of different cytokines from human peripheral blood mononuclear cells (PMBC), i.e., lymphocytes and macrophages, was tested in vitro. Some cultures were activated with lipopolysaccharide (LPS) at time point −3 h and were either left alone (positive control) or exposed to SMF continuously from 0 until 6, 18, or 24 h. The secretion of interleukin IL-6, IL-8, tumor necrosis factor TNF-α, and IL-10 was tested by ELISA. SMF-exposure caused visible morphological changes on macrophages as well as on lymphocytes, and also seemed to be toxic to lymphocytes ([36.58; 41.52]%, 0.308≤p≤0.444), but not to macrophages (<1.43%, p≥0.987). Analysis of concentrations showed a significantly reduced production of pro-inflammatory cytokines IL-6, IL-8, and TNF-α from macrophages compared to negative control ([56.78; 87.52]%, p = 0.031) and IL-6 compared to positive control ([45.15; 56.03]%, p = 0.035). The production of anti-inflammatory cytokine IL-10 from macrophages and from lymphocytes was enhanced compared to negative control, significantly from lymphocytes ([−183.62; −28.75]%, p = 0.042). The secretion of IL-6 from lymphocytes was significantly decreased compared to positive control ([−115.15; −26.84]%, p = 0.039). This massive in vitro evidence supports the hypotheses that SMF-exposure (i) is harmful to lymphocytes in itself, (ii) suppresses the release of pro-inflammatory cytokines IL-6, IL-8, and TNF-α, and (iii) assists the production of anti-inflammatory cytokine IL-10; thus providing a background mechanism of the earlier in vivo demonstrated anti-inflammatory effects of SMF-exposure.  相似文献   

10.
磁场是一种普遍存在的环境因子,但其对微生物的影响尚不清楚.使用超导磁体产生的静态磁场,配以自制实验装置对所选菌株(枯草芽胞杆菌和鼠伤寒沙门氏菌)进行动态磁场处理,比较处理组与地磁场对照组之间包括生长曲线、酶活力等在内的各项生理生化指标,研究动态磁场对微生物的影响.研究发现,动态磁场下两株细菌的生长过程均受到影响.处理组枯草芽胞杆菌对数期提前,衰亡期菌体死亡速率受抑制,碱性蛋白酶活力增加,中性蛋白酶活力降低,而蛋白酶表达量无差异;鼠伤寒沙门氏菌动态磁场处理组对数期推迟,衰亡期菌体死亡亦受到抑制,细菌粘附实验与侵袭力实验表明,细菌毒力相对增强.以上结果表明,动态磁场可对微生物产生影响.并随着微生物种类的不同而异.  相似文献   

11.
12.
实验探讨了超强静磁场(ultra strong static magnetic field,USMF)联合环磷酰胺(cyclophosphamide,CTX)连续处理,对S180荷瘤小鼠抗肿瘤、抗氧化、免疫及骨髓抑制等方面的影响。对S180肉瘤小鼠分组处理后,剥取肉瘤组织称重并进行病理检验。检测过氧化氢酶、超氧化物歧化酶和谷胱甘肽过氧化物酶的活力、总抗氧化能力,以及肝脏和肾脏中丙二醛的含量、脾脏和胸腺指数、脾脏淋巴细胞转化率、外周血中的白细胞数目和骨髓细胞的DNA含量。腹水瘤小鼠同样处理后正常饲养,记录生存时间。结果发现,USMF+CTX组的抑瘤率(72.5%)比CTX组(51.5%)提高了40.8%,生命延长率提高了1.5倍,抗氧化和免疫能力也有一定程度的增强。表明USMF结合CTX,可以协同性抑制S180荷瘤小鼠肿瘤的生长,并减轻CTX对小鼠的副作用。  相似文献   

13.
目的:探讨恒定磁场对日本三角涡虫(Dugesia japonica)无性横裂生殖及抗氧化酶活力的影响.方法:应用种群累积培养法,观察了恒定磁场对日本三角涡虫的种群增长、无性横裂生殖及涡虫体内超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活力的影响.结果:场强大小在200mT-500mT范围的恒定磁场能促进涡虫的无性横裂生殖,但恒定磁场显著抑制涡虫的SOD及CAT活力.结论:日本三角涡虫对恒定磁场的生理学响应较为敏感,可作为生物磁学研究适宜的实验材料.  相似文献   

14.
The effects of weak static magnetic field on the organotypic tissue culture of the rat cerebral cortex, liver, and spleen have been investigated. Exposure to a 200 μT static magnetic field induces tissue development, leading to the intensification of regeneration processes compared to the control explants.  相似文献   

15.
稳恒磁场抑制肿瘤增殖的实验研究与理论探讨   总被引:2,自引:0,他引:2  
朱杰西 《生物磁学》2006,6(1):10-13
作为模型处理最简单的稳恒磁场,其与肿瘤作用的研究是最具理论和实际意义的.分别介绍了稳恒磁场作用于微循环系统、免疫系统对肿瘤的间接抑制和杀伤作用,磁场影响自由基代谢和细胞膜及细胞内结构对肿瘤的抑制作用;回顾了磁场干扰细胞周期、诱导细胞凋亡对肿瘤的影响,并介绍了稳恒磁场联合抗癌药物在治癌中的应用现状;最后结合实验的进展情况,分析探讨了稳恒磁场抑制肿瘤细胞增殖的物理机理,对肿瘤磁疗的发展前景进行了展望.  相似文献   

16.
本文综述了恒磁场、交变磁场、高频磁场和射频磁场等对各种哺乳类动物细胞的作用的最新研究与应用进展;旨在为相关研究提供资料参考.  相似文献   

17.
静磁场对单株人体体表正常菌生长影响的研究   总被引:1,自引:0,他引:1  
本文通过40mT和120mT两种静磁场作用下表皮葡萄球菌生长过程的研究,发现试验所选强度静磁场加速了表皮葡萄球菌在对数生长期的生长速率,而在进入稳定生长期后其生长速率反而低于对照组,但就整个生长周期而言,静磁场作用下表皮葡萄球菌的总量大于对照组,表明了试验所选静磁场对表皮葡萄球菌生长有一定促进作用.  相似文献   

18.
目的:观察不同强度(0.05T、0.08T、0.25T、0.1T)的磁处理水对光合细菌生长的影响。方法:采用分光光度法,半固体试管法。结果:磁场强度为0.05T、0.08T、0.25T的磁处理水对光合细菌的生长有明显的抑制作用(P<0.01);磁场强度为0.1T的磁处理水和对照组(未经磁处理的无菌水)对光合细菌的生长影响不大(P>0.05)。结论:磁处理水对光合细菌的生长有一定的影响,其生长情况与磁场强度有关。  相似文献   

19.
Under subzero degree conditions, free water contained in biological cells tends to freeze and then most living things die due to low temperatures. We examined the effect of a variable magnetic field on Drosophila under supercooled conditions (a state in which freezing is not caused even below the freezing point). Under such supercooled conditions with the magnetic field at 0°C for 72 hours, −4°C for 24 hours and −8°C for 1 hour, the Drosophila all survived, while all conversely died under the supercooled conditions without the magnetic field. This result indicates a possibility that the magnetic field can reduce cell damage caused due to low temperatures in living things.  相似文献   

20.
激光—静电磁场对水稻萌发过程超弱发光影响研究   总被引:2,自引:1,他引:2  
10.5mW He-Ne激光,3500v/cm静电场,0.41T的恒磁场分别处理水稻种子,可使种子萌发过程中超弱发光不同程度增加。萌发种子经5℃低温胁迫后,发光值明显降低。  相似文献   

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