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61.
Yoichi Sakakibara Ryûtarô Iwata Hirotaka Kobayashi Fusao Yamada 《Journal of Forest Research》1996,1(3):169-175
Beetle samples were compared between catches by traps and those on flowers in a Japanese beech (Fagus crenata Blume) forest, in Minakami, Gunma Prefecture, Japan. White plastic traps (Sankei Chemical Co., Ltd.) equipped with benzyl
acetate were set out for a month from July 23 to August 23, 1993, and all beetles captured were collected every six days.
During six days from August 10 to August 16, beetles were captured with traps and on wild flowers (Aruncus sylvester Kostel andAngelica polyclada Franch) at three hour intervals. Over the month, the traps captured 1,677 individuals of 73 species of 20 families, which
included 16 (89%) species captured on flowers in the six-day period. Over the six days, the traps captured 327 individuals
of 21 species of 12 families, compared with 685 individuals of 18 species of 5 families on the flowers; all of the families
and nine (50%) species of beetles taken on the flowers were also captured by the traps; all of the species with more than
five individuals captured on the flowers were also trapped. This suggests that capture by traps might sufficiently cover the
beetle fauna on flowers. The number of species and individuals, as well as their changing patterns, however, varied more irregularly
during the six-day period with the traps than with those on the flowers.
A part of this paper were presented at the 46th meeting of the Kanto Branch of the Japanese Forestry Society (1994)
These English titles are tentative translation by the authors from the originals 相似文献
62.
Wind‐induced stock variation of the neon flying squid (Ommastrephes bartramii) winter–spring cohort in the subtropical North Pacific Ocean 下载免费PDF全文
Haruka Nishikawa Takahiro Toyoda Shuhei Masuda Yoichi Ishikawa Yuji Sasaki Hiromichi Igarashi Mitsuo Sakai Masaki Seito Toshiyuki Awaji 《Fisheries Oceanography》2015,24(3):229-241
Our examination of the neon flying squid (Ommastrephes bartramii) winter–spring cohort catch per unit effort (CPUE, an index of stock) revealed significant positive correlations with the interannual variations of observed chlorophyll‐a (Chl‐a) concentration and autumn–winter mixed layer depth (MLD) in the winter–spring feeding grounds of paralarvae and juveniles (130–170°E, 20–27°N). These correlations suggest the importance of integrated bottom‐up effects by the autumn–winter MLD for the neon flying squid stocks. However, the influence of autumn–winter MLD interannual variation in the forage availability for paralarvae and juveniles, i.e., particulate organic matter and zooplankton, has still been unclear. In this study, we use the lower trophic ecosystem model NEMURO, which uses the physical environmental data from the ocean reanalysis dataset obtained by the four‐dimensional variational (4DVAR) data assimilation method. The model‐based investigation enables us to clarify how the autumn–winter MLD controls the particulate organic matter and zooplankton abundance in the feeding grounds. Further, our investigation of the autumn–winter MLD interannual variation demonstrates that the stronger autumn wind in the feeding grounds develops a deeper mixed layer. Therefore, the deep mixed layer entrains nutrient‐rich water and enhances photosynthesis, which results in good feeding conditions for paralarvae and juveniles. Our results underline that the wind system interannual variation has critical roles on the winter–spring cohort of the neon flying squid stock. 相似文献
63.
64.
Effects of isoprothiolane on cell growth of cultured bovine mammary epithelial cells. 总被引:1,自引:0,他引:1
H Okada Y Miyake H Ohtsuka Y Kiku S Fukuda A Watanabe Y Yokomizo T J Rosol T Yoshino 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(5):553-556
This study was performed to investigate the effects of isoprothiolane on cell growth and the production of interleukin (IL)-1 and IL-6 by bovine mammary epithelial cells in vitro. Isoprothiolane increased proliferation of mammary epithelial cells in a dose-dependent manner at the concentration of 0.05 to 5 microM when cultured either with or without serum-supplemented medium. In contrast, isoprothiolane (0.0005-5 microM) significantly inhibited the production of IL-1 and IL-6 by mammary epithelial cells. Moreover, the cytokines, IL-1alpha, IL-1beta, IL-6, and tumor necrosis factor (TNF)-alpha tended to inhibit the proliferation of mammary epithelial cells in a dose-dependent manner. These results indicated that isoprothiolane regulated mammary epithelial cell growth in vitro possibly by modulating the production of cytokines. 相似文献
65.
2'-epi-orobanchol and solanacol, two unique strigolactones, germination stimulants for root parasitic weeds, produced by tobacco 总被引:2,自引:0,他引:2
Xie X Kusumoto D Takeuchi Y Yoneyama K Yamada Y Yoneyama K 《Journal of agricultural and food chemistry》2007,55(20):8067-8072
Germination stimulants for root holoparasitic weeds broomrapes ( Orobanche and Phelipanche spp.) produced by tobacco ( Nicotiana tabacum L.) were purified and characterized. The root exudates of tobacco contained at least five different stimulants, and LC-MS/MS analyses revealed that four of them were strigolactones; a tetradehydrostrigol isomer, a didehydrostrigol isomer, and two strigol isomers. The two isomers of strigol were identified as (+)-orobanchol and its 2'-epimer by comparison of NMR and GC- and LC-MS data with those of synthetic standards. The structure of the tetradehydrostrigol isomer, the major stimulant of the bright yellow tobacco cultivars, was determined as 4-alpha-hydroxy-5,8-dimethyl-GR24 [( E)-4-alpha-hydroxy-5,8-dimethyl-3-(4-methyl-5-oxo-2,5-dihydrofuran-2-yloxy)methylene)-3a,4-dihydro-3 H-indeno[1,2- b]furan-2(8b H)-one] and named solanacol. 2'-Epi-orobanchol and solanacol are the first natural strigolactones having a 2'-epi stereochemistry and a benzene ring, respectively. 相似文献
66.
Tomomi Kaku Kei’ichi Baba Toru Taniguchi Manabu Kurita Ken-ichi Konagaya Katsuaki Ishii Teiji Kondo Satoshi Serada Haruka Iizuka Rumi Kaida Teruaki Taji Yoichi Sakata Takahisa Hayashi 《Journal of Wood Science》2012,58(4):281-289
The transgenic expression of Aspergillus xyloglucanase cDNA (AaXEG2) with 35S promoter in the leaves of open field-grown poplars was studied. The level of xyloglucan in the transgenic poplars was decreased to 15–16% in the non-fertile soil (forest-field soil) and to 21–22% in the fertile soil (farming-field soil) compared with that of the wild-type poplars. The leaves exhibited a smaller surface area with more rounded teeth than those of the wild-type plants, similar to the sun leaf variety that was grown in the incubation room and subsequently greenhoused. The majority of total veins with water-conducting vascular bundles were shorter in the leaves of the transgenic poplars than those of the wild type. This decrease in vein length may result from a decrease in xyloglucan during leaf development, from which large numbers of proteins were markedly downregulated in the leaves of the transgenic plants via proteomic analysis. It seems likely that the leaves of the transgenic poplars came to relax the edges of their tooth rather than extend their veins as a result of the loosening of the xyloglucan cellulose networks in the leaves. 相似文献
67.
Shizen Ohnishi Noriyuki Miyake Toru Takeuchi Fumiko Kousaka Satoshi Hiura Osamu Kanehira Miki Saito Takashi Sayama Ayako Higashi Masao Ishimoto Yoshinori Tanaka Shohei Fujita 《Breeding Science》2012,61(5):618-624
Soybean dwarf virus (SbDV) causes serious dwarfing, yellowing and sterility in soybean (Glycine max). The soybean cv. Adams is tolerant to SbDV infection in the field and exhibits antibiosis to foxglove aphid (Aulacorthum solani), which transmits SbDV. This antibiosis (termed “aphid resistance”) is required for tolerance to SbDV in the field in segregated progenies of Adams. A major quantitative trait locus, Raso1, is reported for foxglove aphid resistance. Our objectives were to fine map Raso1 and to reveal whether Raso1 alone is sufficient to confer both aphid resistance and SbDV tolerance. We introduced Raso1 into cv. Toyomusume by backcrossing and investigated the degree of aphid antibiosis to foxglove aphid and the degree of tolerance to SbDV in the field. All Raso1-introduced backcross lines showed aphid resistance. Interestingly, only one Raso1-introduced backcross line (TM-1386) showed tolerance to SbDV in the field. The results demonstrated Raso1 alone is sufficient to confer aphid resistance but insufficient for SbDV tolerance. Tolerance to SbDV was indicated to require additional gene(s) to Raso1. Additionally, Raso1 was mapped to a 63-kb interval on chromosome 3 of the Williams 82 sequence assembly (Glyma1). This interval includes a nucleotide-binding site–leucine-rich repeat encoding gene and two other genes in the Williams 82 soybean genome sequence. 相似文献
68.
Recent international summits of the International Federation of Societies of Toxicologic Pathologists (IFSTP) have debated the desirability and potential means by which the proficiency of an individual toxicologic pathologist might be recognized and communicated throughout the world. The present document describes the advantages and disadvantages of implementing such a global recognition system by any means, and provides a proposal whereby recognition might be accorded via rigorous credential review of a practitioner's education and experience. 相似文献
69.
To assess the impacts of clouds during the grain-filling period on the leaf senescence and yield of wheat (Triticum aestivum L.), we conducted a 4-year plot shading experiment in a well-drained Andosol in northern Japan. Plants were shaded after the beginning of anthesis in mid-June, which corresponds to a naturally cloudy period in the study region. The effect of shading depended on its synchronization with soil drying, which affected leaf senescence. Grain yield was determined by solar radiation at the beginning of the grain-filling period, except in 2015, which was a dry year. Later anthesis in 2016 and 2017 significantly reduced the number and weight of individual grains in the shading treatments. Moreover, “Kitahonami”, with late anthesis, showed a significantly slower increase in the individual-grain weight during the grain-filling process after shading than “Yumechikara”. When the duration between anthesis and shading was short, shading significantly reduced the number and weight of grains, and later anthesis makes it more likely that regional reduced light levels are encountered, resulting in fewer grains; the sensitivity of individual-grain weight to shading synchronized with an increase in grain protein contents. Our results suggest that in wet years, later anthesis makes it easier to encounter regional reduced light and fewer grains; in addition, insufficient light limits photosynthesis under shade and decreases yield. 相似文献
70.
Inanami O Shiga A Okada K Sato R Miyake Y Kuwabara M 《American journal of veterinary research》1999,60(4):452-457
OBJECTIVE: To examine the association between oxidative stress and antioxidants in neonatal calves after birth. SAMPLE POPULATION: Sera from 6 healthy Holstein-Friesian cows and 7 of their newborn calves were obtained at various intervals after birth. PROCEDURE: Lipid peroxides in serum of cows and their newborn calves were estimated by measuring concentrations of thiobarbituric acid-reactive substances (TBARS). The antioxidative activities of neonatal sera were evaluated by measuring their superoxide-scavenging activities, ferroxidase activities, and the concentration of bilirubin-associated albumin. RESULTS: Concentration of TBARS in neonatal sera within 1 day after birth was significantly higher than concentrations > or = 2 days after birth and concentrations in serum of the dams. In contrast, antioxidative activities of neonatal sera, evaluated on the basis of superoxide-scavenging activities, ferroxidase activities, and concentration of bilirubin-associated albumin 3 hours after birth, were significantly lower than antioxidative activities in sera of the dams. CONCLUSIONS: Susceptibility of calves to oxidative stress during the neonatal period may be explained by the immature defense system against superoxide radicals. 相似文献