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31.
Noriyoshi Uehara Shigeru Shirakawa Haruto Uchino Yukikazu Saeki Mitsuhiro Nozaki 《Life sciences》1980,26(6):461-467
Ehrlich ascites carcinoma cells (4×105 cells/mouse) were inoculated intraperitoneally in 7-week-old SLC:ICR mice, and polyamine levels in peripheral erythrocytes and in ascites cells were determined periodically. Polyamine levels in peripheral erythrocytes increased linearly until 10 days after cell inoculation, while ascites cells showed exponential growth.The effect of carbazilquinone on cellular growth and polyamine levels in erythrocytes was also studied. When 1 or 2mg/kg of carbazilquinone was injected intraperitoneally on day 4 or on day 7, cellular growth was suppressed and the survival time of the mice was lengthened. The polyamine levels in erythrocytes were also markedly decreased 3 days after the carbazilquinone injection.These results suggest that the polyamine levels in peripheral erythrocytes are closely related to the cellular growth of Ehrlich ascites carcinoma cells. 相似文献
32.
Mössbauer spectra of metapyrocatechase 总被引:1,自引:0,他引:1
33.
Acrosomal ATPase in starfish and bivalve mollusk spermatozoa 总被引:1,自引:0,他引:1
ATPase activity was found in acrosomes of starfish and bivalve mollusk spermatozoa, using a cytochemical method with electron microscopy. The activity was located in central material of the starfish acrosome and in material lining the acrosomal membrane of the Mytilus acrosome, as well as in the basal part of the starfish acrosome. The ATPase activity in the former material was preferably activated by Ca2+, while that in the starfish basal material was preferably activated by Mg2+. Both types of activity persisted during and after the acrosome reaction. ATPase activity was also observed in the region of the axial filament complex of the flagella, in centrioles and in a basal matrix. ATPase in the acrosome also hydrolysed other nucleoside triphosphates. However, there was no detectable phosphatase activity, and little pyrophosphatase or 5′-nucleotidase activity. Evidence was obtained that adenylate kinase may be included in the acrosome. A possible role of the ATPase activity in the acrosome reaction is discussed. 相似文献
34.
Kinoshita Kodzue Indo Yoriko Tajima Tomoyuki Kuze Noko Miyakawa Etsuko Kobayashi Toshio Nakamura Tomoyuki Ogata Mitsuaki Okumura Fumihiko Hayakawa Takashi Morimura Naruki Mori Yusuke Okamoto Munehiro Ozaki Yasuhiko Hirata Satoshi 《Primates; journal of primatology》2021,62(3):475-475
Primates - In the original publication of the article, the coauthor “Takashi Hayakawa” was wrongly assigned as co-corresponding author. 相似文献
35.
36.
Yoriko Yukitatsu Masaki Hata Koji Yamanegi Naoko Yamada Hideki Ohyama Keiji Nakasho Yusuke Kojima Hideki Oka Kenzo Tsuzuki Masafumi Sakagami Nobuyuki Terada 《Cell and tissue research》2013,352(3):647-657
VE-cadherin and claudin-5 are major components of adherens and tight junctions of vascular endothelial cells and a decrease in their expression and an increase in the tyrosine-phosphorylation of VE-cadherin are associated with an increase in endothelial paracellular permeability. To clarify the mechanism underlying the development of edema in nasal polyps, we studied these molecules in polyp microvessels. Normal inferior turbinate mucosal tissues and nasal polyps from patients treated with or without glucocorticoid were stained for VE-cadherin or claudin-5 and CD31 by a double-immunofluorescence method and the immunofluorescence intensities were graded 1–3 with increasing intensity. To correct for differences in fluorescence intensity attributable to a different endothelial area being exposed in a section or to the thickness of a section, the relative immunofluorescence intensity was estimated by dividing the grade of VE-cadherin or claudin-5 by that of CD31 in each microvessel. Tyrosine-phosphorylation of VE-cadherin was examined by Western blot analysis. The relative intensities of VE-cadherin and claudin-5 in the CD31-positive microvessels significantly decreased in the following order; inferior turbinate mucosa, treated polyps and untreated polyps. The ratio of tyrosine-phosphorylated VE-cadherin to VE-cadherin was significantly higher in untreated polyps than in the inferior turbinate mucosa and treated polyps, between which no significant difference in the ratio was seen. Thus, in nasal polyps, the barrier function of endothelial adherens and tight junctions is weakened, although glucocorticoid treatment improves this weakened barrier function. 相似文献
37.
Benjamin W. Tatler Yoriko Hirose Sarah K. Finnegan Riina Pievilainen Clare Kirtley Alan Kennedy 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1628)
Selecting and remembering visual information is an active and competitive process. In natural environments, representations are tightly coupled to task. Objects that are task-relevant are remembered better due to a combination of increased selection for fixation and strategic control of encoding and/or retaining viewed information. However, it is not understood how physically manipulating objects when performing a natural task influences priorities for selection and memory. In this study, we compare priorities for selection and memory when actively engaged in a natural task with first-person observation of the same object manipulations. Results suggest that active manipulation of a task-relevant object results in a specific prioritization for object position information compared with other properties and compared with action observation of the same manipulations. Experiment 2 confirms that this spatial prioritization is likely to arise from manipulation rather than differences in spatial representation in real environments and the movies used for action observation. Thus, our findings imply that physical manipulation of task relevant objects results in a specific prioritization of spatial information about task-relevant objects, possibly coupled with strategic de-prioritization of colour memory for irrelevant objects. 相似文献
38.
Mikio Kawamori Yasushi Morikawa Yoriko Shinsha Kenichiro Takayama Seigo Takasawa 《Bioscience, biotechnology, and biochemistry》2013,77(10):2875-2879
The development of agar plate screening techniques has allowed the isolation of mutants of Trichoderma reesei capable of synthesizing cellulase under the conditions of a high concentration of glucose. Mutants resistant to catabolite repression by glycerol or glucose were isolated on Walseth’s cellulose (WC) agar plates containing 5% glycerol or 5% glucose, respectively. Mutants resistant to catabolite repression by glycerol were not derepressed enough for the production of cellulase on WC agar plates containing 5% glucose or in flask cultures with a mixture of 1% Avicel and 3% glucose. On the contrary, two mutant strains resistant to catabolite repression by glucose (KDD-10 and DGD-16) produced large clearing zones on WC agar plates containing 5% glucose. Both strains could begin to produce CMCase even in the presence of residual glucose and finally produced 1.5 times the CMCase activity, in flask cultures on 1% Avicel and 3% glucose, than that with 1% Avicel alone. These results suggest that KDD-10 and DGD-16 are comparatively derepressed by glucose for cellulase production. 相似文献
39.
Takeshi Saeki Seiya Chiba Tokuji Shimomura 《Bioscience, biotechnology, and biochemistry》2013,77(2):551-552
A water-soluble and neutral polysaccharide was extracted from the current pseudobulbs of Oncidium “Gower Ramsey” during the early inflorescence stage (flower stalk less than 4 cm) by hot water, precipitated with ethanol, and purified with an anion exchanger. From the data of monosaccharide composition and linkage and anomeric configuration analyses, the polysaccharide was identified as a linear β-1→4 linked mannan. 相似文献
40.
Hitomi Yatsuki Ken Higashimoto Kosuke Jozaki Kayoko Koide Junichiro Okada Yoriko Watanabe Nobuhiko Okamoto Yoshinobu Tsuno Yoko Yoshida Kazutoshi Ueda Kenji Shimizu Hirofumi Ohashi Tsunehiro Mukai Hidenobu Soejima 《Genes & genomics.》2013,35(2):141-147
Beckwith-Wiedemann syndrome (BWS) is an imprinting-related human disease that is characterized by macrosomia, macroglossia, abdominal wall defects, and variable minor features. BWS is caused by several genetic/epigenetic alterations, such as loss of methylation at KvDMR1, gain of methylation at H19-DMR, paternal uniparental disomy of chromosome 11, CDKN1C mutations, and structural abnormalities of chromosome 11. CDKN1C is an imprinted gene with maternal preferential expression, encoding for a cyclin-dependent kinase (CDK) inhibitor. Mutations in CDKN1C are found in 40 % of familial BWS cases with dominant maternal transmission and in ~5 % of sporadic cases. In this study, we searched for CDKN1C mutations in 37 BWS cases that had no evidence for other alterations. We found five mutations—four novel and one known—from a total of six patients. Four were maternally inherited and one was a de novo mutation. Two frame-shift mutations and one nonsense mutation abolished the QT domain, containing a PCNA-binding domain and a nuclear localization signal. Two missense mutations occurred in the CDK inhibitory domain, diminishing its inhibitory function. The above-mentioned mutations were predicted by in silico analysis to lead to loss of function; therefore, we strongly suspect that such anomalies are causative in the etiology of BWS. 相似文献