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21.
Hiroshi Kato Taiji Kato Yukio Sakazaki Yosuke Yamakawa Nobuyuki Naganawa Junichi Funabiki Takasumi Kato Ryo Tanaka Akira Masaoka Hidehiko Tsunooka 《Neurochemistry international》1982,4(5):419-426
BL191, a newly developed phosphodiesterase inhibitor, markedly potentiated a differentiation of neuroblastoma cell clones (Neuro2a, NS-20Y, and N1E115) induced by dibutyryl cyclic adensoine 3′:5′-monophosphate(dibutyryl cAMP) and prostaglandin E1 (PGE1). BL191 (1 mM) inhibited DNA synthesis more strongly when used together with PGE1 (0.5 μg/ml) and dibutyryl cAMP (0.5 mM) than papaverine (1.6 μg/ml) alone did. The inhibition rates of DNA synthesis were 72.5% for N1E-115, 75.3% for Neuro2a, and 82.5% for NS-20Y. After the treatment with BL191. PGE1, and dibutyryl cAMP for 48 h all of three cell lines became enlarged and flattened, and extended long processes. The specific activities of choline acetyl transferase (EC 2.3.1.9) of NS-20Y and dopamine β-hydroxylase (EC 1.14.17.1) of N1E-115 increased about 3-fold as compared to the controls. The tumorigenicities of Neuro2a and N1E-115 cells were decreased, but not of NS-20Y. These data suggest the heterogenous responsiveness in neuroblastoma cells to drug treatment. 相似文献
22.
Yoshimitsu Ueno Kohsuke Hori Ryo Yamauchi Makoto Kiso Akira Hasegawa Koji Kato 《Carbohydrate research》1981,96(1):65-72
Laminarabiose, cellobiose, and gentiobiose were acetonated with 2,2-dimethoxy-propane under various conditions. Two isopropylidene acetals in which the reducing D-glucose residue had the furanoid form were obtained from laminarabiose, and two, in which the reducing D-glucose residue formed the acyclic dimethyl acetal, from cellobiose. Gentiobiose gave both types of isopropylidene compound. 相似文献
23.
A synaptosomal plasma membrane fraction and its junctional and nonjunctional subfractions were isolated and analyzed for glycoprotein galactosyltransferase activity. The nonjunctional components fraction had the highest specific activity in the presence of exogenous acceptor, suggesting an enrichment of enzyme in this fraction. The synaptic junctional complex fraction had the highest specific activity in the absence of added acceptor, suggesting that there is a relative enrichment of endogenous acceptors for this galactosyltransferase within the synaptic junctional complex.Presented in part at the 6th meeting of the Society of Neuroscience, Toronto, Ontario, November, 1976 (Goodrum, Bosmann, and Tanaka, 1976) 相似文献
24.
Hiroshi Nakayasu Katsuyoshi Mihara Ryo Sato 《Biochemical and biophysical research communications》1978,83(2):697-703
A membrane-bound aldehyde dehydrogenase was solubilized from rat liver microsomes and purified about 150-fold by chromatography on ω-aminohexyl- and 5′-AMP-Sepharose columns with a recovery of about 40%. The purified enzyme was homogeneous upon sodium dodecyl sulfate-polyacrylamide gel electrophoresis and its monomeric molecular weight was estimated to be 51,000. In aqueous solution, it existed as large, polymeric aggregates. Its activity towards straight-chain aliphatic aldehydes increased as their carbon chain length was increased at least up to dodecanal, whereas aldehyde dehydrogenase in the cytosolic fraction of rat liver was most active with hexanal as substrate. 相似文献
25.
Atsuo Tanaka Takeshige Hagihara Yoshiki Nishikawa Masayoshi Mishina Saburo Fukui 《Applied microbiology and biotechnology》1976,3(2):115-124
Summary The effects of cerulenin, an anti-lipogenic antibiotic, on the growth and cellular fatty acid composition ofCandida lipolytica were investigated by changing the chain length of n-alkane, the growth substrate. The antibiotic inhibited almost completely the growth of the yeast on glucose, n-undecane and n-dodecane, but partly that on n-tridecane. The yeast growth on longer alkanes, e.g., from n-tetradecane to n-octadecane, was not affected by this antibiotic, indicating that a chain elongation system and/or intact incorporation system predominantly operate in the formation of cellular fatty acids from such longer chain n-alkanes. Comparison of the fatty acid profiles between the cells grown on n-alkanes of different chain lengths, especially on n-pentadecane, in the presence and absence of cerulenin, supported the supposition that only the de novo synthesis system of the yeast would be affected by the antibiotic, whereas the chain elongation system would not. 相似文献
26.
DCMU (N'-(3,4-dichlorophenyl)-N, N-dimethylurea) was testedfor effects on the metabolism of galactolipids in Chlorellaand chloroplasts isolated from higher plants. In Chlorella,DCMU affected galactolipid synthesis in the light more thanthat of other lipids, but it showed no effect on lipid synthesisin the dark. DCMU did not affect the turnover of galactolipidsin the light. In vitro studies using 14C-acetate or 14C-UDP-galactoseas a precursor showed that DCMU had no effect on the synthesisof gross lipid or galactolipids in chloroplasts isolated fromhigher plants. The significance of these observations are discussed. (Received September 21, 1974; ) 相似文献
27.
Functional redundancy of multiple forest taxa along an elevational gradient: predicting the consequences of non‐random species loss
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Akira S. Mori Takayuki Shiono Takashi F. Haraguchi Aino T. Ota Dai Koide Takayuki Ohgue Ryo Kitagawa Ryo Maeshiro Toe Toe Aung Taizo Nakamori Yusuke Hagiwara Shunsuke Matsuoka Anzu Ikeda Takuo Hishi Satoru Hobara Eri Mizumachi Andreas Frisch Göran Thor Saori Fujii Takashi Osono Lena Gustafsson 《Journal of Biogeography》2015,42(8):1383-1396
28.
The egg white was treated under various whipping conditions, and its foaminess measured. At the same time, the amounts of the coagulated proteins formed from each egg white and their constituent hexose were measured. From these results, discussions were made about the relation between the foaminess of the egg white and the amount of the coagulated proteins under various whipping conditions. 相似文献
29.
Intrinsic viscosity, Stokes radius and the hydrophobic coefficient of Keshavarz and Nakai [Biochim. Biophys. Acta, 576, 269 (1979)] were measured to compare the shape and surface hydrophobicity of ovalbumin and s-ovalbumin. Both the intrinsic viscosity and Stokes radius of s- ovalbumin were smaller than those of ovalbumin, which suggests that the configuration of s- ovalbumin became more compact during the ovalbumin-s-ovalbumin transformation. The hydrophobic coefficient of s-ovalbumin was larger than that of ovalbumin, which suggests that the surface hydrophobicity of s-ovalbumin was larger than that of ovalbumin. Further, these properties were measured for ovalbumin samples obtained at various stages of ovalbumin-s-ovalbumin transformation. Changes in the shape and surface hydrophobicity of ovalbumin were not found in the first stage of ovalbumin-s-ovalbumin transformation. They changed rapidly in the last stage of the ovalbumin-s-ovalbumin transformation. 相似文献
30.
Limnology - The in-stream processing of nutrients plays an important role in the fluvial nutrient transport from lands to the ocean, but few empirical studies have addressed the temporal dynamics... 相似文献