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The aim of this study is to further measure the effect of 632.8-nm helium-neon laser on fast excitatory postsynaptic potential (f-EPSP) of postganglionic neurons in isolated rat superior cervical ganglia by means of intracellular recording techniques. The neurons with f-EPSP were irradiated by different power densities (1 - 5 mW/cm2) laser. Irradiated by the 2-mW/cm2 laser, the amplitude of the f-EPSP could augment (P < 0.05, paired t test) and even cause action potential at the end of the first 1 - 2 minutes, the f-EPSP could descend and last for 3 8 minutes. But the amplitude of the f-EPSP of neurons irradiated by the 5-mW/cm2 laser could depress for the irradiating periods. The results show that: 1) the variation of the amplitude of f-EPSP caused by laser is power density-dependent and time-dependent; 2) there exist the second-order phases in the interaction of the helium-neon laser with neurons. These findings may provide certain evidence in explanation of the mechanisms of clinical helium-neon lase 相似文献
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人工神经网络及其在分析化学中的应用 总被引:31,自引:1,他引:31
人工神经网络是一种新兴的计算方法,有着广阔的发展前途,目前在分析化学领域已经有了多方面的应用。本文简要介绍了人工神经网络的原理及其在分析化学中的应用。 相似文献
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用前馈线性网络法的不同算法计算了水体系中Pb^2+与OH之间的累积稳定常数,并比较了各种算法的特点,根据计算得到的累积稳定常数,用反馈网络法计算了水溶液中Pb^2+和种化学形态的浓度,△EP随PH变化的模拟曲线,讨论了影响模拟结果的原因,结果表明,测量误差在4〈PH〈9时,CO3^2对Pb^2+形态分布有明显的影响,在实验误差范围内,可以忽略的影响。 相似文献
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The aim of this study is to further measure the effect of 632.8-nm helium-neon laser on fast excitatory postsynaptic potential(f-EPSP)of postganglionic neurons in isolated rat superior cervical ganglia by means of intracellular recording techniques.The neurons with f-EPSP were irradiated by different power densities(1 - 5 mW/cm2)laser.Irradiated by the 2-mW/cm2 laser,the amplitude of the f-EPSP could augment(P < 0.05,paired t test)and even cause action potential at the end of the first 1 - 2 minutes,the f-EPSP could descend and last for 3 - 8 minutes.But the amplitude of the f-EPSP of neurons irradiated by the 5-mW/cm2 laser could depress for the irradiating periods.The results show that:1)the variation of the amplitude of f-EPSP caused by laser is power density-dependent and time-dependent; 2)there exist the second-order phases in the interaction of the helium-neon laser with neurons.These findings may provide certain evidence in explanation of the mechanisms of clinical helium-neon laser therapy. 相似文献
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人工神经网络用于高效液相色谱分析条件的优化 总被引:12,自引:1,他引:11
本文采用人工神经网络的线性网络法(LMS)优化高效液相色谱的分析条件,考察了样本集类型和不同初始权值对优化结果的影响。结果表明,模拟的精度与样本集类型有关,而在一定置信区间与初始权值无关。 相似文献
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A Quantitative Analysis of Modulation of the Fast Excitatory Postsynaptic Potential of Neurons in Rat Sympathetic Ganglia by a Low-Intensity Laser 下载免费PDF全文
We propose a mathematical model which can quantitatively describe the kinetics of postsynaptic membrane potential modulated by a low intensity laser. By virtue of the numerical computation, it is found that the height of peak of fast excitatory postsynaptic potential (f-EPSP) for intermediate laser power density (around 2mW/cm^2) is higher than that for both small and large laser power densities, that is, of the f-EPSP peak height changes with the increasing laser power density (up to 5 m W/cm^2) in non-monotonic behaviour. The theoretical results are qualitatively consistent with the previous experimental data. 相似文献
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火电厂PM2.5环境影响评价方法探讨 总被引:2,自引:0,他引:2
现行的大气导则中尚缺乏针对PM2.5的评价模型、方法及监测要求.通过长三角重点控制区某扩建火电厂排放的一次PM2.5和产生的光化学二次PM2.5对周围环境的影响预测,提出了火电厂一次PM2.5排放量估算的方法,并提出了火电厂PM2.5(包括一次和二次)对周围环境影响的预测方法.评价结果表明,具有光化学反应的CALPUFF模型能有效预测一次和二次PM2.5的生成,在环境影响评价现状监测因子中,因氮氧化物的削减对降低空气中PM2.5的浓度有显著效果,建议增加NH3和O3指标;在环境影响评价中CALPUFF模型可以作为PM2.5环境影响评价的预测模型. 相似文献
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