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911.
I E Gurski? Ts V Serbeniuk P Ia Romanovski? 《Zhurnal evoliutsionno? biokhimii i fiziologii》1988,24(4):545-550
It has been shown that thyroliberin and its synthetic analogue PR-546 injected into the lymphatic sacs (4.10(-7)-4.10(-9) g/kg) or applied to the medulla oblongata in the bulbar frogs (4.10(-10)-4.10(-12) g/kg) significantly increase the rate of motor respiratory volleys in the hypoglossal nerve. In preparations with the irregular level of the activity of the respiratory center, these drugs enhanced stabilization of the initial level of the rhythm of motor respiratory discharges. 相似文献
912.
V V Snitinski? 《Zhurnal evoliutsionno? biokhimii i fiziologii》1988,24(5):702-707
Studies have ben been made on the activity of hexokinase, glucokinase, phosphofructokinase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, as well as NADP-dependent dehydrogenases (malate and citrate) in the liver of foetuses and newborn piglets in relation to their age, fasting and reaction to injection of adaptive hormones (insulin and cortisol). It was shown that postpartum adaptation of carbohydrate metabolism in porcine liver is associated with activation of the glycolysis and with the increase in the activity of NADPH-generating dehydrogenases. In fasting newborn piglets the rate of carbohydrate catabolism increases. The effects of the investigated factors are different in the liver of 1-day piglets (sensitive to fasting) and 5-day animals (less sensitive). In is suggested that low ability of newborn piglets to maintain physiological level of glucose in the blood is associated with active glycolysis in the liver and ineffectiveness of the hormone-substrate mechanisms which control tissue glycaemia. 相似文献
913.
V G Nare?ko 《Ontogenez》1988,19(6):601-605
Changes in the myosin isozyme spectrum were studied in the loach developing skeletal muscle. It was shown using disk-electrophoresis in polyacrylamide gel and peptide mapping that light and heavy myosin chains from the larval muscles, as well as from the red and white muscle of adult fish differ from each other. Forms of myosin light and heavy chains were found which were characteristic of the larval muscle only. 相似文献
914.
The cell cycle structure in the cells of loach embryos at the early blastula stage (5 h of development at 21 degrees) is markedly altered under the influence of injection of homologous low molecular weight nuclear RNA and, as a result, the number of cells in G2-phase. The DNA amount in the embryo increases by 20%. At the midblastula stage (7 h) no increase in the number of cells in G2-phase was found. 相似文献
915.
T I Buzhievskaia T L Cha?kovskaia G V Skiban T E Zerova-Liubimova T P Kochube? 《T?Sitologii?a i genetika》1988,22(3):25-29
Three unusual cases of Down's syndrome inheritance are presented which permit supposing that microstructural chromosome aberrations in parents may induce not only a structural imbalance of chromosomal material in progeny, but also a numerical imbalance. 相似文献
916.
A G Maksina B A Da?niak I V Rakhmanova 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1988,(11):61-64
The structural changes in cat brain membranes under the injections of intramuscular streptomycin which is ototoxic antibiotic have been studied. The increase of membrane microviscosity in brain areas which are the direct projection of the auditory way has been revealed using fat acidic spin probe on the basis of stearic acid. The changes in membranes of other brain areas have not been found that exhibits a specific streptomycin influence on the auditory analyzer. The EPR spectra of the hydrocarbon spin label C12H25 localizing in near membrane region don't change in brain membranes of experimental animals compared with the normal ones. 相似文献
917.
918.
T Gomez R Rial A Bola?os M Molina 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1988,90(1):203-205
1. Lizards Gallotia galloti received daily 3 mg/kg body wt of diphenylhidantoin (DPH) over a period of 15 days and at the same time the animals were kindled. 2. The progression of the kindling effect was evaluated by counting the number of spontaneous epileptiform potentials, the duration of afterdischarges and the duration of electroencephalographic spontaneous seizures. 3. The diphenylhidantoin treated group, relative to controls presented: (a) significant reduction in the duration of afterdischarges and spontaneous electroencephalographic seizures; and (b) increased frequency of the spontaneous epileptiform potentials. 相似文献
919.
920.
Hypoxia led to a dramatic acceleration of amino acid breakdown together with succinate synthesis in the rat heart. Our data do not confirm the simultaneous conversion of aspartate and glutamate to succinate, which has been repeatedly assumed in the literature (7, 8, 21, 28-30), but rather suggest that different pathways are involved during developing hypoxia and that glutamate is the sole source for anaerobic succinate production from endogenous sources in the glucose-perfused heart. Perfusion of hypoxic rat hearts with 2-oxoglutarate, malate, and fumarate (5 mM each) increased succinate formation three- to fourfold. The beneficial effects of these substances on left ventricular systolic pressure, end diastolic pressure, and time of recovery may be due to the elevated content of ATP in these hearts compared to hypoxic controls with glucose as the sole substrate. However, the maintenance of a high rate of anaerobic glycolysis in hearts perfused with 2-oxoglutarate, malate, and fumarate and not the small stimulation of succinate synthesis is considered to be the most important mechanism of cardiac protection. A proposed pathway assumes that malate, after dehydration to fumarate, may serve as an alternative electron acceptor for cytosolic NADH during conditions of oxygen deficiency, thereby cancelling glycolytic inhibition. 相似文献