104
2 Holographic Microscopy of Phase and Diffuse Objects …
remained spare. By this, the possibility of the recording “stimulating” and “inhibited”
action of pulsed magnetic field on the nerve state was obtained.
After this, the nerve was stimulated by 1 Hz-frequency electric current. Meanwhile, response amplitude value was fixed. The information was continuously
recorded during 1–3 h except for the periods of the influence of powerful pulsed
magnetic field. The parameters were the following: Field intensity was 25 kE, pulse
duration was 0.5 ms, pulse repetition frequency was 1 Hz, and there were 50 pulses.
The obtained results were processed statistically. For the study of the reliability
of average difference, we calculated average value (x) with confidence interval (d)
on 5% significance level using the following formula: x ± d, where d = t 0.005 m
−
x ,
and m
−
x = σ/
√
n − 1.
In the case of confidence interval overlapping, we considered average value differences doubtful. The average value was calculated every 5 s by 10–15 AP amplitude
values and also directly after the influence of pulsed magnetic field. The results of
the processing are shown in Table 2.1.
At all, 23 frog sciatic nerves were studied. Each preparation was used for 10–15
measurements of the influence of powerful pulsed magnetic field. The experimental
data allow detecting true amplitude changes of nerve AP under the influence of
a magnetic field. The results of the second experiment (Table 2.1) reveal the most
character pattern of AP amplitude changes under the influence of the pulsed magnetic
field. This reaction has a complex time-multi-directional structure.
It is seen from Table 2.1 that the first two influences of pulsed magnetic field
lead to the true AP amplitude increase, the third one does not influence the nerve
functional state index under consideration, and the following influences (5 tests)
cause true decrease of amplitude, which in 2–3 min recovers reference quantity to
the value before “inhibitory” action.
One more interesting peculiarity of the influence of a powerful pulsed magnetic
field on the indexes under study should be mentioned. In experiment No. 14, we
observed spontaneous AP amplitude incidence caused by the damage of the nerve
trunk in the process of separation. Along with the progressive decrease of AP value,
there was noticed strongly expressed “stimulating” influence of pulsed magnetic
field. The essence of this is that the measuring parameter truly increases by 25–40%
directly after the influence.
Thus, the following peculiarities can be marked of the influence of powerful pulsed
magnetic field on the functional state of frog isolated sciatic nerve:
1. The influence of pulsed magnetic field leads to the true increase of AP amplitude
caused by electric stimulation.
2. Time-consecutive stimulations by pulsed magnetic field cause multi-directional
changes of AP value: At first, we observed “stimulating” action changed into
“inhibitory” action (it was observed in 89% experiments). One of the experiments
(No. 14) allows predetermining the modeling influence of the nerve functional
state on the value of the response.
Thus, it should be noticed that using pulsed magnetic field in clinical practice,
there must be considered the detected dose-dependent effect of the changes in the
2 Holographic Microscopy of Phase and Diffuse Objects …
remained spare. By this, the possibility of the recording “stimulating” and “inhibited”
action of pulsed magnetic field on the nerve state was obtained.
After this, the nerve was stimulated by 1 Hz-frequency electric current. Meanwhile, response amplitude value was fixed. The information was continuously
recorded during 1–3 h except for the periods of the influence of powerful pulsed
magnetic field. The parameters were the following: Field intensity was 25 kE, pulse
duration was 0.5 ms, pulse repetition frequency was 1 Hz, and there were 50 pulses.
The obtained results were processed statistically. For the study of the reliability
of average difference, we calculated average value (x) with confidence interval (d)
on 5% significance level using the following formula: x ± d, where d = t 0.005 m
−
x ,
and m
−
x = σ/
√
n − 1.
In the case of confidence interval overlapping, we considered average value differences doubtful. The average value was calculated every 5 s by 10–15 AP amplitude
values and also directly after the influence of pulsed magnetic field. The results of
the processing are shown in Table 2.1.
At all, 23 frog sciatic nerves were studied. Each preparation was used for 10–15
measurements of the influence of powerful pulsed magnetic field. The experimental
data allow detecting true amplitude changes of nerve AP under the influence of
a magnetic field. The results of the second experiment (Table 2.1) reveal the most
character pattern of AP amplitude changes under the influence of the pulsed magnetic
field. This reaction has a complex time-multi-directional structure.
It is seen from Table 2.1 that the first two influences of pulsed magnetic field
lead to the true AP amplitude increase, the third one does not influence the nerve
functional state index under consideration, and the following influences (5 tests)
cause true decrease of amplitude, which in 2–3 min recovers reference quantity to
the value before “inhibitory” action.
One more interesting peculiarity of the influence of a powerful pulsed magnetic
field on the indexes under study should be mentioned. In experiment No. 14, we
observed spontaneous AP amplitude incidence caused by the damage of the nerve
trunk in the process of separation. Along with the progressive decrease of AP value,
there was noticed strongly expressed “stimulating” influence of pulsed magnetic
field. The essence of this is that the measuring parameter truly increases by 25–40%
directly after the influence.
Thus, the following peculiarities can be marked of the influence of powerful pulsed
magnetic field on the functional state of frog isolated sciatic nerve:
1. The influence of pulsed magnetic field leads to the true increase of AP amplitude
caused by electric stimulation.
2. Time-consecutive stimulations by pulsed magnetic field cause multi-directional
changes of AP value: At first, we observed “stimulating” action changed into
“inhibitory” action (it was observed in 89% experiments). One of the experiments
(No. 14) allows predetermining the modeling influence of the nerve functional
state on the value of the response.
Thus, it should be noticed that using pulsed magnetic field in clinical practice,
there must be considered the detected dose-dependent effect of the changes in the