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31.
32.
High-affinity specific receptors of endothelin (ET-1) were identified on primary cultures of mouse embryo striatal astrocytes by binding experiments performed with 125I-ET-1. Stimulation of production of inositol phosphates, a biphasic increase of the intracellular calcium concentration, and inhibition of cyclic AMP accumulation were observed in the same cells under ET-1 stimulation. Pretreatment of these cells with Bordetella pertussis toxin affected these effects to different extends, an observation suggesting that they are mediated by multiple transduction pathways, possibly involving several guanine nucleotide-binding proteins. 相似文献
33.
Phenylalanine Ammonia-Lyase Genes from Pisum sativum: Structure, Organ-Specific Expression and Regulation by Fungal Elicitor and Suppressor 总被引:3,自引:0,他引:3
34.
35.
Katsuhiko Tachibana Yoshifumi Yamamoto Etsuro Osaki Yoshikazu Kuroki 《Human genetics》1980,54(2):283-286
Summary A 7-month-old boy with the cerebro-costomandibular syndrome is presented. This is the first case report in an Oriental population.15 reported cases in the literature are reviewed. 相似文献
36.
Yoshikazu Kuroki Ichiro Matsui Yoshifumi Yamamoto Atsushi Ieshima 《Human genetics》1980,55(2):227-229
Summary Disomic and trisomic cells of a patient with Down syndrome mosaic were used to study the effect of the additional chromosome 21 against an identical genetic background. The frequency of Ag staining and the participation in satellite associations were determined for each pair of acrocentric chromosomes. The additional chromosome 21 of the trisomic cells and its homologues proved to be regularly Ag positive. Therefore the trisomic cells showed more Ag positive chromosomes and more satellite associations per cell than the diploid cells. Thus, no compensation for the additional rRNA-gene dose could be found in the cells of the trisomic line. 相似文献
37.
38.
Yoshikazu Yazaki 《Journal of plant research》1976,89(1):45-57
Pure or genuine malvin was isolated fromFuchsia petals for the first time and characterized as the malvin anhydro-base. The conditions for the co-pigmentation were examinedin vitro with regard to anthocyanin, co-pigment and pH, and the co-pigmentation occurred as the result of interaction between anthocyanin and co-pigment without any participation of metallic elements. The blue-violet color of youngFuchsia petals appeared at pH 4.8 in the 1∶0.6 molar ratio of anthocyanin to co-pigments. The color change from blue-violet in young petals to purple-red in old ones was caused by co-pigmentation and the pH change from 4.8 to 4.2. The decrease of pH in the old petals was due to the increase of organic acids such as aspartic, malic and tartaric acids. 相似文献
39.
Several compounds containing a thiomethyl group were found to replace vitamin B12 in a protozoan, Ochromonas malhamensis. The order of the effectiveness was as follows: 5-methylthioadenosine > S-adenosylmethionine > 5-methylthioribose > L-methionine. A similar order was obtained with respect to the permeability of these compounds into the protozoan cells, except for S-adenosylmethionine. 5-Methylthioadenosine and 5-methylthioribose as well as l-methionine markedly increased the intracellular content of l-methionine. The level of S-adenosylmethionine was also increased by them, but to a lesser degree. The thiomethyl group of the compounds was established to be incorporated into S-adenosylmethionine. The metabolic fate of the thiomethyl group of 5-methylthioadenosine cannot be distinguished from that of l-methionine. A high activity of 5-methylthioadenosine nucleosidase was detected in the cell-free extracts of the protozoan. These results strongly suggest that 5-methylthioadenosine would be metabolized to l-methionine via 5-methylthioribose and then the l-methionine would be converted to S-adenosylmethionine. Like l-methionine and vitamin B12, 5-methylthioadenosine and 5-methylthioribose may play an important role in maintenance of the C-1 pool in Ochromonas malhamensis.Neither 5-methylthioadenosine nor 5-methylthioribose replaced vitamin B12 in some vitamin B12-requiring bacteria. This result is consistent with the fact that neither compounds was significantly taken up by these bacteria.Abbreviations MTA
5-methylthioadenosine
- AdoMet
S-adenosylmethionine
- MTR
5-methylthioribose
- TCA
trichloroacetic acid
Paper II in the series. The first paper of the series has been published (Sugimoto and Fukui, 1974) 相似文献
40.
Using thin film of synthetic pyroelectric material, polyvinylidene fluoride, sensitive heat-sensors were constructed for the purpose of detecting heat production associated with the phenomenon of spreading depression in isolated amphibian retinae. Measurements with these sensors revealed the existence of large heat production, which closely follows the electrical sign of spreading depression. Studies of the effects of chemical agents known to affect spreading depression have demonstrated the usefulness of heat measurements. 相似文献