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891.
Summary Pineal N-acetyltransferase activity in the male Syrian hamster exhibited a daily rhythm; the maximal night-time value was 3.5-fold higher than the day-time value. When hamsters were exposed to light at night N-acetyltransferase declined within 30 min to 1/5 of its former activity. These results indicate that in the Syrian hamster the pineal melatonin rhythm may be regulated at least partly via changes in N-acetyltransferase activity.The authors are grateful to Mrs Marie Svobodová for her skillful technical assistance. 相似文献
892.
M. Pospíšil J. Jary Jaromíra Netíková M. Marek 《Cellular and molecular life sciences : CMLS》1982,38(10):1232-1234
Summary A single pre- or postirradiation application of -(13)-D-glucan, a potent reticuloendothelial stimulant, enhances hemopoietic recovery in sublethally gamma-irradiated mice. Pretreatment of mice with glucan significantly reduces lethal radiation effects. 相似文献
893.
Summary Electrical correlates of the lateralized reaching reaction were studied in rats with implanted electrodes. Averaged event-related potentials (ERPs) in the cerebellar dentate nucleus consisted of a negative wave coinciding with reach onset and followed 70 msec later by a positive deflection. The most prominent component of the more variable caudate ERPs was a negative wave culminating 60–120 msec after reach onset. The positive and negative ERP deflections corresponded to inhibitory and excitatory reactions respectively, at the single neuron level. 相似文献
894.
Summary The dynamic and static phases of the thermogenic response to i.v. infused noradrenaline (NA) do not reflect the arterial concentration of NA; according to the equation presented here they are a function of the influx rate. 相似文献
895.
V. Wagner M. Wagnerová J. Kříž D. Wokounová B. Šlesingerová 《Cellular and molecular life sciences : CMLS》1976,32(11):1369-1371
Summary In a group of 84 pairs of 11-year-old children of both sexes, the level of the
1-antitrypsin (
1-AT) were ascertained in the autumn and spring. Although the mean levels of
1-AT in the two seasons hardly differed, the highly significant seasonal changes in the distribution curves of
1-AT values were noted in boys, whereas the levels showed higher stability in girls. 相似文献
896.
M. Aušková K. Řežábek V. Zikán M. Semonský 《Cellular and molecular life sciences : CMLS》1974,30(4):393-394
Summary The inhibiting effect of orally administered N-[d-6-methyl-8-isoergolin-I-yl], N, N-diethylurea (VÚFB-6638) on the production of milk was found in rats. The inhibition of lactation was ascertained through the observation of the daily weightgains of the suckled puppies (ED50=0.112 mg/kg/day) and through the observation of the presence of milk in the stomach of these puppies, as seen through their abdomen wall (0.084 mg/kg/day). This inhibition could be abolished with exogenous prolactin, which gives evidence that the drug studied acts via the endocrine system.
Für die technische Assistenz danken wir FrauM. Kommersová und FrauV. Maitová. 相似文献
Für die technische Assistenz danken wir FrauM. Kommersová und FrauV. Maitová. 相似文献
897.
J. Marec Jarmila Keprtová Věra Spurná Eva Minářová J. Michl 《Cellular and molecular life sciences : CMLS》1977,33(1):33-34
Summary The uptake of exogenous3H-DNA by mammalian cells is increased in the presence of a specific serum protein complex — growth-promoting alpha-globulin (GPAG).3H-DNA is retained in the cell nucleus in a quantity 3 times higher than for control cultures without GPAG even after 47h of additional cultivation in the medium without3H-DNA. 相似文献
898.
Summary Ricinoleic acid was found in differentClaviceps sp., indicating that it is neither specific chemotaxonomic marker ofClaviceps purpurea, nor a specific indicator of peptide alkaloid synthesis. 相似文献
899.
Summary The effect of ionizing radiation on the amount of dopamine in corpus striatum was investigated in rats exposed to 650 or 850 R of X-rays. The amount of dopamine in the corpus striatum was measured fluorimetrically in various periods of time after irradiation. It was found that, irrespective of the dose applied, the ionizing radiation caused a significant depletion of dopamine in the striatum. 相似文献
900.
Summary Serum from rats exposed for 3 days to 5 °C stimulated the multiplication of mouse heteroploid and human and rat diploid cells in culture. The response of the cells to this unspecific growth stimulation was related to the growth capacities of the different cell types. 相似文献