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271.
Abstract— In contrast to mouse brain, the content of putrescine in fish brain considerably exceeds that of spermine and spermidine. While we observed constant protein, RNA and spermidine concentrations in fish brains of weights between 60 and 800 mg, DNA and spermine concentrations diminished with increasing brain weight, the content of spermine per cell being constant throughout life. It can be concluded from our results that growth of fish brain results both from cell enlargement and cell proliferation. The concomitant changes of spermine and DNA concentrations in the growing fish brain are the first example of a direct quantitative relationship between these cell constituents and provides evidence on their possible functional relationship in the cell nucleus. 相似文献
272.
N. G. Morozova M. A. Maslov V. V. Myagchenkov G. A. Serebrennikova 《Russian Journal of Bioorganic Chemistry》2010,36(5):657-662
An approach to the synthesis of cationic carbohydrate surfactants with potential antimicrobial and transfecting activities
is proposed. 相似文献
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Ferredoxin from Bacillus polymyxa 总被引:5,自引:0,他引:5
Y I Shethna N A Stombaugh R H Burris 《Biochemical and biophysical research communications》1971,42(6):1108-1116
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The [3H]ketanserin binding characteristics in the apomorphine-induced aggressive and nonaggressive adult male Wistar rats were studied. Repeated apomorphine (0.5 mg/kg, once daily) treatment gradually induced aggressive behaviour in sixteen animals from twenty. Thereafter the animals were retrospectively divided into apomorphine-induced aggressive and nonaggressive group. The maximal number of the [3H]ketanserin binding sites was increased in the apomorphine-treated animals in the frontal (233.9+/-26.5, 364.6+/-31.7, and 367.0+/-34.8 fmol/mg protein for the vehicle, apomorphine-nonaggressive, and apomorphine-aggressive group, respectively) and cerebral cortex (164.2+/-6.7, 289.7+/-29.3, and 249.0+/-15.4 fmol/mg protein for the vehicle, apomorphine-nonaggressive, and apomorphine-aggressive group, respectively). In conclusion, our experiments demonstrate that repeated apomorphine treatment upregulates the maximal number of the 5-HT2A receptors in rat frontal and cerebral cortex as measured by [3H]ketanserin binding and this phenomenon is independent from the development of aggressive behaviour. 相似文献
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