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911.
V Krajca 《Activitas nervosa superior》1984,26(2):118-128
Use of the dynamic clusters method for automatic extraction of compressed information about recorded EEG signal is presented. The computer first divides the record into quasi-stationary segments by means of adaptive segmentation. Second, the extracted segments are classified by a method of dynamic clusters into homogeneous classes. One part of the used clustering algorithm permits to specify and draw the most typical class members, which may represent the whole studied EEG signal and may be used as input for the further phase of the automatic EEG analysis, i.e. for the classification of the whole EEG records. The above procedure was applied to a 75 sec long EEG record of anaesthetized cat intoxicated by CO. 相似文献
912.
S. V. Marshall 《BMJ (Clinical research ed.)》1939,1(4079):535-536
913.
914.
The aerobic NADPH reduction of cytochrome P-450LM has been investigated on microsomes, as well as on the solubilized enzyme system in the associated, disintegrated, and reconstituted state, respectively. P-450 exhibits biphasic reduction kinetics of about 70/30% phase distribution and rate constants differing 10-fold. The partial reactions are due to organizational asymmetries, the cytochrome being either incorporated into P-450/reductase associates (cluster) or localized outside (randomly distributed, homoassociated, weakly cluster-associated). Triton N-101 disintegrates the different associate structures, consequently followed by the disappearance of the rapid reaction phase. The enzyme system can be reconstituted; at microsomal stoichiometry the respective standard parameters are approached, depending on the composition and structural organization of the phospholipid. The reorganization without any membrane matrix is obviously thermodynamically determined. 相似文献
915.
S K Tandon A K Mathur J R Behari S V Chandra 《Acta biologica et medica Germanica》1975,34(11-12):1835-1842
Daily intraperitoneal administration of thorium nitrate produced progressive morphological and biochemical alterations with the increase in thorium concentration in rat testis. The degenerative changes in the seminiferous tubules increased with the duration of treatment and after 90 days calcification occurred in about 25% of the tubules and in the connective tissue of the tunica albuginea. The activity of adenosine triphosphatase and alkaline phosphatase increased markedly as a result of thorium administration. An attempt has been made to interrelate histopathological and enzymatic changes and the metal concentration in the testicular tissue. 相似文献
916.
917.
918.
KUENKEL VH 《California medicine》1952,77(6):374-376
Gross and microscopic anatomical evidence indicates that pain fibers involved in causalgia are those distributed to blood vessels-possibly to the arterioles-and that, for the greater part, these fibers constitute part of the general visceral afferent system. Several investigators have reported evidence that injury to a peripheral nerve of such a type as to cause damage to the vasomotor control of any area produces the initial pain in an extremity, and it is predicated that the arteriolar constriction causing the pain is then prolonged by the sensitization of arteriolar smooth muscle to the amount of epinephrine normally in the blood. If the condition is not treated, tissue anoxia occurs to such an extent that irreversible changes take place in the affected area.Treatment of causalgia in the lower extremities is directed toward interruption of either the vasomotor or afferent supply of blood vessels by blocking or excision of the second to fourth lumbar ganglia inclusive with the intervening chains. For the upper extremities, the blocking or disconnection of the second and third thoracic ganglia with interruption of the sympathetic chain between the third and fourth ganglia is considered a feasible method of treatment which does not produce the concomitant disability of Horner's syndrome. 相似文献
919.
920.
Serotonergic status in human blood 总被引:5,自引:0,他引:5