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51.
Michio Nakamura Nadia Corp Mariko Fujimoto Shiho Fujita Shunkichi Hanamura Hitoshige Hayaki Kazuhiko Hosaka Michael A. Huffman Agumi Inaba Eiji Inoue Noriko Itoh Nobuyuki Kutsukake Mieko Kiyono-Fuse Takanori Kooriyama Linda F. Marchant Akiko Matsumoto-Oda Takahisa Matsusaka William C. McGrew John C. Mitani Hitonaru Nishie Koshi Norikoshi Tetsuya Sakamaki Masaki Shimada Linda A. Turner James V. Wakibara Koichiro Zamma 《Primates; journal of primatology》2013,54(2):171-182
We have analyzed the ranging patterns of the Mimikire group (M group) of chimpanzees in the Mahale Mountains National Park, Tanzania. During 16 years, the chimpanzees moved over a total area of 25.2 or 27.4 km2, as estimated by the grid-cell or minimum convex polygon (MCP) methods, respectively. Annually, the M group used an average of 18.4 km2, or approximately 70 %, of the total home-range area. The chimpanzees had used 80 % of their total home range after 5 years and 95 % after 11 years. M group chimpanzees were observed more than half of the time in areas that composed only 15 % of their total home range. Thus, they typically moved over limited areas, visiting other parts of their range only occasionally. On average, the chimpanzees used 7.6 km2 (in MCP) per month. Mean monthly range size was smallest at the end of the rainy season and largest at the end of the dry season, but there was much variability from year to year. The chimpanzees used many of the same areas every year when Saba comorensis fruits were abundant between August and January. In contrast, the chimpanzees used several different areas of their range in June. Here range overlap between years was relatively small. Over the 16 years of the study we found that the M group reduced their use of the northern part of their range and increased their frequency of visits to the eastern mountainous side of their home range. Changes in home-range size correlated positively with the number of adult females but not with the number of adult males. This finding does not support a prediction of the male-defended territory model proposed for some East African chimpanzee unit-groups. 相似文献
52.
Michio Himeno Yukio Kimura Keizo Hayashiya 《Bioscience, biotechnology, and biochemistry》2013,77(8):1457-1462
Embryos of the silkworm, Bombyx mori L., were dispersed by trypsin and the dissociated cells were cultured for infection with nuclear polyhedrosis virus (NPV) of the silkworm. The monolayer and suspension cultures were infected with NPV. RNA and DNA syntheses in the normal and NPV-infected cells were measured by incorporation of 32P into RNA and DNA fractions. RNA and DNA syntheses in the cells after infection significantly increased over those in control cells (mock infection). The effects of actinomycin D, chloramphenicol and mitomycin C on RNA and DNA syntheses in infected cells were examined. The syntheses were inhibited by the antibiotics. It was suggested that the cellular DNA synthesis was inhibited by the viral infection, because the mitomycin C-resistant DNA synthesis was found in the normal cells but not in the infected cells treated with mitomycin C. The rate of DNA synthesis induced by NPV was immediately dropped to that of control cells by addition of chloramphenicol, while the RNA synthesis induced by NPV was not affected for 6 hr after the addition of chloramphenicol. If the antibiotic did not affect the size of precursor pools, this event suggested that the RNA polymerase concerned with viral RNA synthesis was more stable than the DNA polymerase participating in the viral DNA synthesis. The viral DNA as templates for RNA and DNA syntheses was decomposed by mitomycin C. 相似文献
53.
Akira Sakurai Saburo Tamura Naohiko Yanagishima Chikashi Shimoda Michio Hagiya Narao Takao 《Bioscience, biotechnology, and biochemistry》2013,77(1):231-232
5-Fluorotryptophan (5FT), indolmycin (IM), 4-fluorotryptophan and 7-azatryptophan were found on screening to be tryptophan antagonists among various chemically synthesized and naturally occurring tryptophan analogues for the isolation of l-tryptophan (l-Trp) producing mutants of Bacillus subtilis K.From among 5FT resistant mutants, potent l-Trp producers were obtained using an improved isolation medium. Growth of the isolated 5FT-resistant l-Trp producer, AJ 11709, was inhibited by IM. From among 5FT and IM resistant mutants, the best strain, AJ 11979, which produced 9.0 g/liter of l-Trp from 13% glucose on 120hr cultivation, was selected. 相似文献
54.
Michio Nakayama 《Bioscience, biotechnology, and biochemistry》2013,77(4):362-371
The quinary system KCl-K2SO4-MgCl2-MgSO4-Mg(OH)2-H2O and associated eight systems K2SO4-MgSO4-Mg(OH)2-H2O, MgCl2-MgSO4-Mg(OH)2-H2O, KCl-MgCl2-Mg(OH)2-H2O, KCl-K2SO4-Mg(OH)2-H2O, MgSO4-Mg(OH)2-H2O, MgCl2-Mg(OH)2-H2O, K2SO4-Mg(OH)2-H2O and KCl-Mg(OH)2-H2O were investigated at 50° The solid phases of these systems were the new basic triple salt (NS salt B), MgCl2 · 3Mg(OH)2 · 8H2O, MgSO4 · 5Mg(OH)2 · 3H2O, carnallite, leonite, kieserite, hexahydrite, bischofite, potassium chloride, potassium sulfate and magnesium hydroxide and the crystallization fields of these salts in nine systems were determined. 相似文献
55.
Michio Himeno Naoto Koyama Tomohiko Funato Tohru Komano 《Bioscience, biotechnology, and biochemistry》2013,77(5):1461-1468
Cultured insect cells, TN-368 from the cabbage looper, swelled and burst upon treatment with the enzyme-digested delta-endotoxin of Bacillus thuringiensis var. aizawai. The cytotoxic sweelling was depended upon the amount of the delta-endotoxin added and the concentration of NaCl or KC1 in the isotonic solution. The concentration of Na+ in the swollen cells approximately doubled in isotonic NaCl, while that of K+ decreased to 10% of the original cellular concentration. The cell swelling was inhibited by tetrodotoxin and also by ouabain in only KC1 isotonic solution. On the other hand, 4-aminopyridine stimulated the swelling in the isotonic KC1 solution, These results indicate that the delta-endotoxin induces the stimulation of Na+ influx and K+ efflux in the isotonic NaCl solution, and also stimulates the Na+, K+-ATPase in the isotonic KC1 solution. The cytotoxic swelling was also blocked by cAMP, AMP, ATP, GTP, and NAD, but not by adenosine and GMP. These results suggest the participation of nucleotide derivatives in the action of delta-endotoxin. 相似文献
56.
Junichi Ueda Takao Yokota Nobutaka Takahashi Michio Yoshida Jiro Kato 《Bioscience, biotechnology, and biochemistry》2013,77(12):3083-3086
A root growth-promoting factor was isolated from Artemisia capillaris Thunb. The chemical structure of this compound was elucidated as methyl 3-(3-methylbut-2-enoyl)-4-hydroxycinnamate (capillarol) on the basis of its spectroscopic analysis. At 5×10–4m this compound promoted rice root growth to 180% of the control value. 相似文献
57.
58.
Watanabe T Saito D Tanabe K Suetsugu R Nakaya Y Nakagawa S Takahashi Y 《Developmental biology》2007,305(2):625-636
The in ovo electroporation technique in chicken embryos has enabled investigators to uncover the functions of numerous developmental genes. In this technique, the ubiquitous promoter, CAGGS (CMV base), has often been used for overexpression experiments. However, if a given gene plays a role in multiple steps of development and if overexpression of this gene causes fatal consequences at the time of electroporation, its roles in later steps of development would be overlooked. Thus, a technique with which expression of an electroporated DNA can be controlled in a stage-specific manner needs to be formulated. Here we show for the first time that the tetracycline-controlled expression method, "tet-on" and "tet-off", works efficiently to regulate gene expression in electroporated chicken embryos. We demonstrate that the onset or termination of expression of an electroporated DNA can be precisely controlled by timing the administration of tetracycline into an egg. Furthermore, with this technique we have revealed previously unknown roles of RhoA, cMeso-1 and Pax2 in early somitogenesis. In particular, cMeso-1 appears to be involved in cell condensation of a newly forming somite by regulating Pax2 and NCAM expression. Thus, the novel molecular technique in chickens proposed in this study provides a useful tool to investigate stage-specific roles of developmental genes. 相似文献
59.
60.
Nishi D Koido Y Nakaya N Sone T Noguchi H Hamazaki K Hamazaki T Matsuoka Y 《PloS one》2012,7(4):e35248