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111.
The nephrotoxicity of cephaloridine, cefazolin and mercuric chloride was studied in rabbits of various ages. Cephaloridine produced dose-related elevations in serum urea nitrogen, creatinine and renal tubular necrosis in adult and 30-day-old rabbits, only slight changes at 15 days of age and no effect in 5-day-old rabbits. Cefazolin also produced dose-related nephrotoxicity in adult rabbits but no effect in 15-day-old rabbits. Mercuric chloride administration resulted in similar nephrotoxicity in 5-, 15- and 30-day-old rabbits and adults. The development of susceptibility to cephaloridine nephrotoxicity paralleled the maturation of the renal anionic transport system as determined by the accumulation of p-aminohippurate by renal cortical slices in vitro. Substrate stimulation of the anionic transport system by p-aminohippurate or penicillin increased the nephrotoxicity of cephaloridine in between rabbits. The authors concluded that the lack of cephaloridine nephrotoxicity in newborn rabbits is due to the incomplete development of the renal anionic transport system.  相似文献   
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The isoenzyme composition of lactate dehydrogenase of soleus and plantaris muscles of rats flown for 20.5 d aboard the biosatellite Cosmos-690 and irradiated with a dose of 800 rad was investigated. The muscles exposed to weightlessness per se and weightlessness combined with radiation showed similar changes in their carbohydrate metabolism. On return to 1 G, readaptation of irradiated rats developed less rapidly than of animals exposed to weightlessness alone.  相似文献   
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An adult cattle egret (Bubulcus ibis) caught in Kobe of Hyogo Prefecture, Japan, in December 1995 died of a severe infection associated with the trematode parasite Pegosomum sp. At necropsy, 22 trematode parasites were found in the lumen of the bile duct, and the duct wall was markedly thickened. Histopathologically, severe cholangitis and cholecystitis were observed in close association with the parasites in the bile duct. Severe Pegosomum sp. infection may be one of the factors contributing to the mortality of wild cattle egrets. This is the first reported case of the genus Pegosomum infection in wild birds of Japan.  相似文献   
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Effects of 7-min cardiac arrest and individual behavior on free radical-mediated processes and nitric oxide synthase (NOS) activity was evaluated in brains of male Wistar rats one hour and one week after resuscitation. "Emotional resonance" test was used for the behavioral selection of rats. The test includes factors of significance for rats: the choice between large and lighted or small and dark space as well as signals of pain of another rat. Free radical generation (using chemiluminescence method), superoxide scavenging/generating activity, substances reacting with 2-thiobarbituric acid and NOS activity (by measuring mononitrosyl iron complex of NO with diethyl dithiocarbamate and endogenous brain Fe2+ by electron spin resonance spectroscopy) were determined in cerebral cortex, cerebellum and hippocampus. Cardiac arrest induced oxidative stress accompanied by the loss of NOS activity, as well as compensatory changes of free radical-mediated processes in cerebral cortex. Oxidative stress was also evident in cerebellum and, to a lesser extent, in hippocampus. Most of neurochemical differences between behavioral groups were induced by cardiac arrest. These differences were global, related to a specific brain region or became apparent in cerebral lateralization of biochemical indices.  相似文献   
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In accordance with the fundamental concept of the systems symmetrical approach, a model of the body's "ideal functional status" and a polyparametric method for diagnosing the human functional status (the method has been patented in Russia) were developed, on the basis of the unified set of amplitude and time parameters of a complex of physiological parameters (ECG, etc.). The systems symmetrical approach is basically new in defining the ratio of harmonic parameters acting as new diagnostic evidence for the health status. The unchanging ratio of parameters of autovariation processes in the cardiac, vascular, and respiratory systems, their changes in the development of the adaptative syndrome and the value were examined in healthy individuals at rest and during exercise an intensive productive activity (point brazing at a plant of electron devices), and in the trainees. It was demonstrated that the mechanism of development of adaptative processes was associated with the synchronization of autovariations in the cardiorespiratory and vascular systems and the involution of adaptative processes, their break, depletion, i.e. stress, were determined by the imbalance of relationships and the desynchronization of autovariations in these systems. To define a set of cardiorespiratory and hemodynamic parameters is necessary, but insufficient to evaluate (diagnose) the health status and health-disease intermediate diseases (stress and adaptative overtension). The ratio harmonicity of these parameters, i.e. well-balanced relations between the subsystems is the main characteristic. The assessment of the human health status in terms of the reference-the model of the ideal status as the ideal health status without using the complex and indefinite concept of the normal and moderate health status-is conceptual for polyparametric status estimation.  相似文献   
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