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321.
Zusammenfassung Die interne-Bestrahlung in kleinen Dosen vergrössert den 5-Hydroxytryptamin-Inhalt des zentralen Nervensystems der Ratte: Gehirnrinde, Dyencephalus, Hypothalamus, Geruchbulbe, Mittelhirn und Rückenmark. Bei Experimenten mit höheren Dosen (über 500 rad) sinkt der 5-Hydroxytryptamin-Gehalt.

This work has been carried out under a grant from the International Atomic Energy Agency, Vienna; contract No. 95 RB/1-RB/2.  相似文献   
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P D Gupta 《Experientia》1966,22(6):374-375
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Summary Scavenging studies are supporting the notion that triplet radical cations are formed during the binding of the carcinogen N-acetoxy-2-acetylamino-fluorene to native DNA in vitro.This work was supported by Grant No.3305.78 of the Swiss National Science Foundation and by a grant from The Roche Research Foundation.  相似文献   
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Summary remarks It is evident that the bulbar EEG is a complex response which can be influenced by several methodological and stimulant variables. What EEG patterns tell us about actual behavior remains obscure. The bulbar EEG which is evoked by homestream water is not necessarily a reflection of olfactory memory. The evoked bulbar EEG also does not necessarily demonstrate the salmon has distinguished the home-water from another water in terms of migrational orientation. Despite lack of absolute specificity, a correlation between bulbar EEG and actual behavioral performance has been observed even though some non-home waters evoke responses similar to that of the home water. In general it has been found that the home water response can be distinguished from the response to other natural waters. Failure to obtain complete specificity may be due to a variety of variables which have been alluded to earlier in this section. Thus considering that the evoked EEG is a reflection of the integration of a diverse afferent input, further electrical and computer analyses may eventually permit the decoding of the EEG in terms of behavior. However, if the EEG proves to be more a quantitative rather than qualitative reflection of brain activity, relating EEG to behavior will prove to be of limited value. Since afferent responses in the olfactory bulb are influenced by impulses from higher brain centers, studies on centrifugal aspects during olfactory stimulation may be useful in gaining some qualitative understanding of the home water evoked EEG of the olfactory bulb.  相似文献   
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Riassunto Gli autori hanno studiato l'inibizione dellal-glutamina-d-fruttosio-6-fosfato amidotransferasa per 5-nucleotidi in estratti crudi di cartilagine di pollo. L'inibizione per 5-adenilato e altri 5-nucleotidi segue una cinetica competitiva. Il 2- e 3-adenilato, così come il ribosio 5-fosfato non sono inibitori. Gli autori prospettano una possibile participazione nelle regolazione della sintesi degli aminozuccheri.  相似文献   
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Summary The aim of the present study was to investigate the effects of a cholesterol-rich diet on membrane function and lipid composition in rabbit myocardium. The activity and the ouabain sensitivity of the K-p-nitrophenylphosphatase (K-pNPPase), a partial reaction of the Na, K-ATPase, were diminished after a cholesterol/oil or pure cholesterol diet. The content of cholesterol, cholesterol esters and of several classes of phospholipids was enhanced in microsomes. A causal relationship is assumed between cholesterol accumulation and a decrease in membrane fluidity as well as in Na, K-ATPase activity. The intracellular Na content and the Na-Li-exchange rate were higher after the cholesterol diet. The increase in the Na content is supposed to be induced by a lower Na transport and a higher Na permeability. An enhanced Ca flux via the sarcolemma could be the consequence.To whom reprints should be addressed  相似文献   
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