Research on electricity frequency property of blood / 生物医学工程学杂志

On the basis of our previous work, the electric frequency property of human blood in different components, in physiological state and in pathological state (diabetes) are tested and analyzed in the range of 1Hz-20MHz progressively. Among the different components of blood; the lowest electrical impedance is serum; the plasma and the whole blood gradually become larger, the blood corpuscle is the largest one. Otherwise, the negative phase of serum is the largest, the plasma and the whole blood are lower, and the blood corpuscle is the lowest. Here, the question is why the effect of the electric capacity of serum and plasma is the biggest in the condition of no cell and cell membrane; diabetes mellitus is an endocrine disorder in which blood changes obviously, the electric frequency property of the blood of diabetic patients changes markedly; the electrical impedance of blood decreases (more obviously with low frequency), the negative phase increases (more obviously with high frequency). These indicate that the increase of electric conductivity in diabetic patients' blood is due to electric capacitance conductivity that is related to the changes of cell membrane, deformation abilities and aggregation of RBC. Related experiments demonstrate again that with the progressing of research in the electric frequency property of blood, we may use the theory and method of electricity to examine some important characters of blood in a different way, and so to corroborate other tests and analyses.

Measuring the electricity frequency properties of blood / 生物医学工程学杂志

In order to understand the electricity frequency specialties of blood, we have developed a wide frequency electricity characteristic testing system and used it to test the amplitude frequency property and phase frequency property of the blood in different states and constituents at 1 Hz to 20 MHz. Further analysis on the results of tests helped us know some important properties of blood at even more microcosmic levels from a new angle. Meanwhile, some problems and considerations on the improvement of the electricity model of biotic tissue and blood were pointed out. (1) From 1 Hz to 5 KHz, the impedance of blood descended 99%. (2) Simple equivalent circuit of resistance and capacitance must be used in series equivalent but not in usual parallel connection equivalent. (3) Experiment indicated, equivalent circuits of blood need more analysis, because simple equivalent circuit of resistance and capacitance is liable to gross error. (4) When the three element model is used for measuring the resistance of inside liquid, capacitance of cell membrane and the resistance of outside liquid of blood, the three testing frequencies must be very similar.

Effect of different types of counterion on the electronic structure of an antitumor polyoxomolybdate Mo7O246- / 生物医学工程学杂志

The electronic structure of a Lindqvist type [Mo7O24]6- anion with 5 different types of counterion (K+, Na+, NH4+, [NH3Pr]+ and [NH3Pri]+) was calculated by using the Discrete Variational Method coupled with Density Functional Theory (DFT-DVM). It could be concluded through variance analysis to the calculated results that the type of counterion does not influence remarkably the electronic structure of [Mo7O24]6- anions. Perhaps it can be used to explain the experiment fact that the polyoxomolybdate structure of the Mo7O24 framework is apparently of critical significance to antitumor action. On these grounds we forecast that two other lindqvist type heptamolybadates(their counterions are Na+ and [NH3Pr]+ respectively) may also exhibit antitumor activities.