Biulleten' eksperimental'noĭ biologii i meditsiny
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Biull Eksp Biol Med · Jul 1979
Comparative Study[Reaction of the ganglia to stress effects in the maxillodental area].
Neurohistologic and histochemical study has been performed of the trigeminal and upper cervical sympathetic ganglia as well as of the nodose ganglion in 35 dogs whose 4 lower teeth were prepared for full metal crowns. It was established that in the polishing of dental hard tissue the ganglia on the prepared side show changes in some neurons, intraganglionic nerve fibers, synaptic endings, in the content and distribution of RNA, glycogen and hyaluronic acid. The maximal evidence of the reaction was noted 1--3 days after operation. The ganglia under study did not show any marked changes following 21--28 days.
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Biull Eksp Biol Med · Jun 1979
[Effect of the duration of the previous ischemia and of the mass of ischemic tissue on the state of the coagulating and anticoagulating blood systems in tourniquet shock].
In the experiments on 80 rabbits it was shown that the inclusion of the previously ischemized extremities into circulation is accompanied by elevation of coagulating potential of the blood and inhibition of fibrinolysis shortly after the tourniquet removal followed by hypocoagulation and fibrinolysis activation. These changes depend on the duration and mass of previously ischemized tissues. It is suggested that in tourniquet shock these disorders lead either to the danger of intravascular thrombosis or to hypocoagulation with secondary fibrinolysis.
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Biull Eksp Biol Med · Apr 1975
[Combined effects of hypoxia and hypercapnia on the functional state of the respiratory center].
Experiments were conducted on cats under nembutal anesthesia; a study was made of pulse activity of bulbar respiratory neurons, electrical activity of the diaphragm and of the intercostal muscles; pO2, pCO2, pH, arterial blood oxygen saturation were determined in combined action of hypoxia and hypercapnia. When hypoxic gaseous mixture was given for respiration the developing hypocapnia disturbed the discharge rhythmic activity of the respiratory neurons, the respiration acquiring a pathological character of the Cheyne--Stokes type. After addition to the hypoxic gaseous mixture of 2% CO2 the gaseous composition of the arterial blood approached the initial values; this addition prevented the development of hypercapnia and disturbances of rhythmic discharge activity of the respiratory neurons. Addition of 5% CO2 to the hypoxic gaseous mixture produced a negative effect: at first it intensified and then depressed the pulse activity of the respiratory neurons, caused metabolic and respiratory acidosis, and promoted asphyxia.