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991.
Toshiyuki Nagata Ashley DuVal Hans Walter Lack George Loudon Mark Nesbitt Michaela Schmull Peter R. Crane 《Economic botany》2013,67(2):87-97
An Unusual Xylotheque with Plant Illustrations from Early Meiji Japan. Two unusual wood collections, reported previously in the collections of the Botanical Museum at Berlin-Dahlem and the Royal Botanic Gardens, Kew, take the form of framed plant illustrations painted on boards made from the wood of the species illustrated. We present new finds of very similar wood collections in the Economic Botany Collection of the Harvard University Herbaria, a private collection in the U.K. (Loudon collection), and at the Koishikawa Botanical Garden of the University of Tokyo. A stamp on the reverse of the boards links all five collections to Chikusai Kato, an artist working at Tokyo University (now the University of Tokyo) in early Meiji Japan, under the direction of the preeminent nineteenth century Japanese botanist Keisuke Ito. New evidence from contemporary historical accounts indicates that more than 100 boards were ordered in June 1878 by Hiroyuki Katō, the first president of Tokyo University, most likely to support the early teaching of Western-influenced botanical science in Japan. However, while the boards had clear value for teaching, especially about useful plants, their unusual fusion of Western and Japanese influences also made them desirable craft objects that were collected and given as gifts during the early Meiji era. 相似文献
992.
Shinji Jinno Yoshitaka Nakamura Masashi Nagata Takeshi Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(5):861-866
To examine the effect of dietary supplementation with 1-kestose on the IgA levels in milk, BALB/c mice were fed diets with or without 5% 1-kestose during pregnancy and lactation. The total and specific IgA levels in the milk were measured at 7 and 14?days after delivery. A two-way ANOVA with repeated measures resulted in a significant effect of 1-kestose-supplementation on total IgA concentrations (p?<?0.05) and the level of anti-Bacteroides IgA (p?<?0.05). A significant positive correlation was found between the mean count of Bacteroides spp. in maternal feces and the total IgA concentration in maternal milk (r?=?0.55, p?<?0.05), suggesting a potential link between the gut and mammary gland immune system. In conclusion, this study demonstrated the effects of dietary prebiotics on milk IgA production. 相似文献
993.
Yukio Nagata Yukio Nakamura Tadashi Watanabe 《Bioscience, biotechnology, and biochemistry》2013,77(4):717-722
Activities of AChE and ChE per g wet weight of the cerebrum were higher in the cerebrum of the MAM-induced microencephalic rats that were the offspring of the mother rats injected on the 15th day of pregnancy with MAM-acetate than in the normal rats cerebrum. They increased for 30 days after birth and were maintained constant thereafter. The activity of AChE more increased in the cerebral subcortex than in other regions. With the increase in dose of the drug administered to mother rats, the cerebral weight of their offspring decreased gradually whereas AChE activity per g wet weight of their cerebrum increased. These findings support existence of plasticity in the cerebrum. 相似文献
994.
Yoichiro Sakai Zin’ichi Karube Tomohiro Takeyama Ayato Kohzu Chikage Yoshimizu Toshi Nagata Ichiro Tayasu Noboru Okuda 《Limnology》2013,14(2):167-177
Identifying sources of particulate organic matter (POM) is important for clarifying fundamental mechanisms by which lake food webs are sustained. We determined carbon and nitrogen stable isotope ratios of POM in near-shore waters of Lake Biwa, a large, meso-eutrophic lake in Japan, to estimate relative contributions of terrigenous particulate organic carbon (T-POC), plankton-derived POC (P-POC) and epilithon-derived POC (E-POC) to POC in near-shore waters. Samples were collected during different months (November, February, May and July) at 29 sites located near the mouth of tributary rivers with different discharge and catchment land use. The data revealed that POC mainly consisted of P-POC and T-POC, with relative contributions varying widely over season and among locations. E-POC generally contributed little to the near-shore POC. Path analyses revealed that the concentration of riverine POC whose isotopic signatures were similar to those of rice straws increased with a larger %paddy field area in the catchment of tributary rivers, which subsequently enhanced T-POC inputs to near-shore waters through riverine transportation. Furthermore, our results suggested that T-POC contribution was influenced, with a time lag, by wave-driven turbulence and shore topography, which appear to affect sedimentation and resuspension of T-POC. 相似文献
995.
996.
Sasaki S Tamaki Y Nagata K Kobayashi Y 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(2):774-780
We found previously that neutrophil-depleted mice exhibited significant blockading of both the regular estrous cycle and cyclic changes of steroid hormone levels. In this study, we aimed at elucidation of the underlying mechanism. To examine the possibility that an increase in bacteria in the vaginal vault of neutrophil-depleted mice causes blockading of the estrous cycle, we treated neutrophil-depleted mice with antibiotics but failed to restore the estrous cycle. We then examined another possibility that neutrophils regulate the estrous cycle via opioid peptides, because opioid peptides regulate steroidogenesis in theca and granulosa cells in the ovaries, and because neutrophils contain opioid peptides. In support of this possibility, naloxone, an opioid antagonist, blocked the estrous cycle and a μ opioid receptor agonist restored the estrous cycle in neutrophil-depleted mice. Pro-opiomelanocortin was immunohistochemically detected in peripheral blood neutrophils but not in ones that had infiltrated into the ovaries. i.v. injection of anti-MIP-2 polyclonal Ab caused blockading of the estrous cycle, whereas MIP-2 was detected in the ovaries, suggesting a role of MIP-2 in the regulation of the estrous cycle. Moreover, i.v. injection of MIP-2 decreased the pro-opiomelanocortin signal in peripheral blood neutrophils and caused blockading of the estrous cycle. Together, these results suggest that neutrophils maintain the estrous cycle via opioid peptides. 相似文献
997.
Phytophagous insects do not constantly chew their diets; most of their time is spent in a non-feeding quiescent state even though they live on or around their diets. Following starvation, phytophagous insect larvae exhibit enhanced foraging behaviors such as nibbling and walking similar to the sequential behavior that occurs prior to each meal. Although extensive physiological studies have revealed regularly occurring feeding behaviors in phytophagous insects, little has been elucidated regarding the mechanism at the molecular level. Here, we report identification and characterization of a novel 62-amino acid peptide, designated as hemolymph major anionic peptide (HemaP), from the hemolymph of Bombyx mori larvae that induces foraging behaviors. The endogenous HemaP levels are significantly increased by diet deprivation, whereas refeeding after starvation returns them to basal levels. In larvae fed ad libitum, hemolymph HemaP levels fluctuate according to the feeding cycle, indicating that locomotor-associated feeding behaviors of B. mori larvae are initiated when HemaP levels exceed an unidentified threshold. Furthermore, administration of exogenous HemaP mimics the starvation-experienced state by affecting dopamine levels in the suboesophageal ganglion, which coordinates neck and mandible movements. These data strongly suggest that fluctuation of hemolymph HemaP levels modulates the regularly occurring feeding-motivated behavior in B. mori by triggering feeding initiation. 相似文献
998.
Ushiroda K Maruta K Takazawa T Nagano T Taiji M Kohno T Sato Y Horai S Yanagi K Nagata R 《Bioorganic & medicinal chemistry letters》2011,21(7):1978-1982
In our search for new PPARα/γ agonists, we designed and synthesized a series of benzoylazole-based carboxylic acids. Compound 9 showed potent PPARγ partial agonistic activity with modest PPARα agonistic activity. The sodium salt of 9 (9Na) demonstrated potent efficacy in lowering both blood glucose and lipids in an animal model without causing significant body weight gain, a well-known side effect associated with PPARγ full agonists. 相似文献
999.
Yoshikawa K Yoshino T Yokomizo Y Uoto K Naito H Kawakami K Mochizuki A Nagata T Suzuki M Kanno H Takemura M Ohta T 《Bioorganic & medicinal chemistry letters》2011,21(7):2133-2140
We previously reported on a series of cyclohexanediamine derivatives as highly potent factor Xa inhibitors. Herein, we describe the modification of the spacer moiety to discover an alternative scaffold. Ethylenediamine derivatives possessing a substituent at the C1 position in S configuration and phenylenediamine derivatives possessing a substituent at the C5 position demonstrated moderate to strong anti-fXa activity. Further SAR studies led to the identification of compound 30h which showed both good in vitro activity (fXa IC50 = 2.2 nM, PTCT2 = 3.9 μM) and in vivo antithrombotic efficacy. 相似文献
1000.
Raquel Pedrosa Bezerra Marcelo Chuei Matsudo Sunao Sato Attilio Converti João Carlos Monteiro de Carvalho 《Bioenergy Research》2013,6(3):1118-1125
To reduce CO2 emissions from alcoholic fermentation, Arthrospira platensis was cultivated in tubular photobioreactor using either urea or nitrate as nitrogen sources at different light intensities (60 μmol m?2 s?1?≤?I?≤?240 μmol m?2 s?1). The type of carbon source (pure CO2 or CO2 from fermentation) did not show any appreciable influence on the main cultivation parameters, whereas substitution of nitrate for urea increased the nitrogen-to-cell conversion factor (Y X/N ), and the maximum cell concentration (X m ) and productivity (P X ) increased with I. As a result, the best performance using gaseous emissions from alcoholic fermentation (X m ?=?2,960?±?35 g m?3, P X ?=?425?±?5.9 g m?3 day?1 and Y X/N ?=?15?±?0.2 g g?1) was obtained at I?=?120 μmol m?2 s?1 using urea as nitrogen source. The results obtained in this work demonstrate that the combined use of effluents rich in urea and carbon dioxide could be exploited in large-scale cyanobacteria cultivations to reduce not only the production costs of these photosynthetic microorganisms but also the environmental impact associated to the release of greenhouse emissions. 相似文献