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991.
Yamawaki M Nishi K Nishimoto S Yamauchi S Akiyama K Kishida T Maruyama M Nishiwaki H Sugahara T 《Bioscience, biotechnology, and biochemistry》2011,75(5):859-863
Matairesinol is one of the lignan compounds found in a variety of plant foodstuffs. We investigated the immunomodulatory effects of (-)-matairesinol in vivo and ex vivo by using mice. Although we found no significant differences in the IgG, IgA and IgM levels in the serum, the IgE level was strongly suppressed by the uptake of (-)-matairesinol in both intact and ovalbumin-immunized mice. The immunoglobulin produced by lymphocytes from the spleen was not activated by the intake of (-)-matairesinol. However, lymphocytes in such gut-associated lymphatic tissues as Peyer's patches and mesenteric lymph nodes were activated by the administration of (-)-matairesinol. 相似文献
992.
Nishiwaki H Nagaoka H Kuriyama M Yamauchi S Shuto Y 《Bioscience, biotechnology, and biochemistry》2011,75(4):780-782
Four imidacloprid derivatives with an asymmetrically methylated imidazolidine ring were synthesized. Their affinity to the nicotinic acetylcholine receptor of housefly Musca domestica and insecticidal activity against the housefly were measured. The compound with a 5R-methylated imidazolidine ring demonstrated intrinsic activity comparable to that of the unsubstituted compound. Most of the compounds were synergized by oxygenase inhibitors. 相似文献
993.
Masae I. Ishihara Satoshi N. Suzuki Masahiro Nakamura Tsutomu Enoki Akio Fujiwara Tsutom Hiura Kosuke Homma Daisuke Hoshino Kazuhiko Hoshizaki Hideyuki Ida Ken Ishida Akira Itoh Takayuki Kaneko Kaname Kubota Koichiro Kuraji Shigeo Kuramoto Akifumi Makita Takashi Masaki Kanji Namikawa Kaoru Niiyama Mahoko Noguchi Haruto Nomiya Tatsuhiro Ohkubo Satoshi Saito Takeshi Sakai Michinori Sakimoto Hitoshi Sakio Hirofumi Shibano Hisashi Sugita Mitsuo Suzuki Atsushi Takashima Nobuyuki Tanaka Naoaki Tashiro Naoko Tokuchi Toshiya Yoshida Yumiko Yoshida 《Ecological Research》2011,26(6):1007-1008
This data paper reports tree census data collected in a network of 34 forest sites in Japan. This is the largest forest data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Forty-two permanent plots, usually 1?ha in size, were established in old-growth or secondary natural forests. Censuses of woody species ??15?cm girth at breast height were conducted every year or once during 2004 to 2009. The data provide species abundance, survivorship and stem girth growth of 52,534 individuals of 334 tree and liana species. The censuses adopted common census protocol, which provide good opportunities for meta-analyses and comparative studies among forests. The data have been used for ecological studies as well as for the biodiversity reports published by the Ministry of the Environment. 相似文献
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996.
BARBARA RANDLKOFER ELISABETH OBERMAIER JÉRÔME CASAS TORSTEN MEINERS 《Ecological Entomology》2010,35(4):446-455
1. A heterogeneous habitat structure can have a profound impact on foraging carnivorous arthropods. In the present study, we examined which elements of complex vegetation structure influence the searching movement of a parasitoid model organism. 2. Previous field work showed that tall and dense vegetation reduces the parasitism success of the eulophid egg parasitoid Oomyzus galerucivorus while the probability of host egg deposition increased close to plant tips. 3. In laboratory bioassays, dried grass stems were arranged according to the natural situation in different setups. The wasps' walking time on stems increased with increasing stem height and density. High stem density decreased the walking time of the parasitoids on the ground and an increased stem height reduced the propensity to fly to the ground. Connectivity had a minor positive effect on the number of stem contacts, but considerably reduced the number of wasps reaching the upper part of grass stems by two‐thirds. 4. Thus, although enhanced vegetation complexity enhances walking activity of the parasitoids in the vegetation, laying eggs at the tip of long grass stems in dense vegetation can be an adaptive strategy for the host, as it maximises the number of connections between plant parts to cross by parasitoids before reaching the host. The connection points disorient the wasps, which lose time, reverse their direction or fly away. 相似文献
997.
Steven B. Kraines David R. Wallace Yumiko Iwafune Yoshikuni Yoshida Toshiya Aramaki Kazuhiko Kato Keisuke Hanaki Hisashi Ishitani Tomonori Matsuo Hiroshi Takahashi Koichi Yamada Kenji Yamaji Yukio Yanagisawa Hiroshi Komiyama 《Journal of Industrial Ecology》2001,5(1):35-54
The evaluation of tradeoffs between technologies and policies for mitigation of environmental problems requires a systematic investigation of effects over the entire region under consideration. When attempting to model such large complex systems, issues such as usability, maintenance, and computing efficiency often become major modeling barriers. In this work a software prototype for integrating the services of computational models over the Internet, called DOME (distributed object-based modeling environment) is used to facilitate the construction of virtual Tokyo—a simulation platform for evaluating holistically the tradeoffs between various technologies for reducing the emissions of greenhouse gases. In making steps toward this ultimate goal, two models have been developed that use data defining spatial land-use distributions and the flows of goods expressed as an input-output table to provide information on the spatial and temporal characteristics of an urban region. Integrated, these models form a preliminary virtual Tokyo model when applied to Tokyo-specific databases. Given this platform, process models are applied to examine the effectiveness of using photovoltaic (PV) modules on the demand side to reduce conventional electric power generation and, thereby, also reduce carbon dioxide emissions. The results of introducing PV modules on the rooftops of buildings in Tokyo under various installation conditions are presented as a working example of the prototype. For full deployment on usable rooftop space, PV power generation could reduce carbon dioxide emissions from electric power generation by more than 12%. Future work will use the same methods as presented in this paper to examine cost, a critical determinant in the actual feasibility of PV module installation. 相似文献
998.
Naho Morisaki Mandy B. Belfort Marie C. McCormick Rintaro Mori Hisashi Noma Satoshi Kusuda Masanori Fujimura the Neonatal Research Network of Japan 《PloS one》2014,9(2)
IntroductionWhether parenteral nutrition benefits growth of very low birth weight (VLBW) preterm infants in the setting of rapid enteral feeding advancement is unclear. Our aim was to examine this issue using data from Japan, where enteral feeding typically advances at a rapid rate.MethodsWe studied 4005 hospitalized VLBW, very preterm (23–32 weeks'' gestation) infants who reached full enteral feeding (100 ml/kg/day) by day 14, from 75 institutions in the Neonatal Research Network Japan (2003–2007). Main outcomes were weight gain, head growth, and extra-uterine growth restriction (EUGR, measurement <10th percentile for postmenstrual age) at discharge.Results40% of infants received parenteral nutrition. Adjusting for maternal, infant, and institutional characteristics, infants who received parenteral nutrition had greater weight gain [0.09 standard deviation (SD), 95% CI: 0.02, 0.16] and head growth (0.16 SD, 95% CI: 0.05, 0.28); lower odds of EUGR by head circumference (OR 0.66, 95% CI: 0.49, 0.88). No statistically significant difference was seen in the proportion of infants with EUGR at discharge. SGA infants and infants who took more than a week until full feeding had larger estimates.DiscussionEven in infants who are able to establish enteral nutrition within 2 weeks, deprivation of parenteral nutrition in the first weeks of life could lead to under nutrition, but infants who reached full feeding within one week benefit least. It is important to predict which infants are likely or not likely to advance on enteral feedings within a week and balance enteral and parenteral nutrition for these infants. 相似文献
999.
Natsuko Okamoto Takahiro Aoto Hisashi Uhara Satoshi Yamazaki Hidenori Akutsu Akihiro Umezawa Hiromitsu Nakauchi Yoshiki Miyachi Toshiaki Saida Emi K. Nishimura 《Pigment cell & melanoma research》2014,27(6):1039-1050
Determination of the niche for early‐stage cancer remains a challenging issue. Melanoma is an aggressive cancer of the melanocyte lineage. Early melanoma cells are often found in the epidermis around sweat ducts of human volar skin, and the skin pigmentation pattern is an early diagnostic sign of acral melanoma. However, the niche for melanoma precursors has not been determined yet. Here, we report that the secretory portion (SP) of eccrine sweat glands provide an anatomical niche for melanocyte–melanoma precursor cells. Using lineage‐tagged H2B‐GFP reporter mice, we found that melanoblasts that colonize sweat glands during development are maintained in an immature, slow‐cycling state but renew themselves in response to genomic stress and provide their differentiating progeny to the epidermis. FISH analysis of human acral melanoma expanding in the epidermis revealed that unpigmented melanoblasts with significant cyclin D1 gene amplification reside deep in the SP of particular sweat gland(s). These findings indicate that sweat glands maintain melanocyte–melanoma precursors in an immature state in the niche and explain the preferential distribution of early melanoma cells around sweat glands in human volar skin. 相似文献
1000.
Yoshiyuki Watanabe Hisashi Tanaka Akio Tsukabe Yuki Kunitomi Mitsuo Nishizawa Ryota Hashimoto Hidenaga Yamamori Michiko Fujimoto Masaki Fukunaga Noriyuki Tomiyama 《PloS one》2014,9(8)