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排序方式: 共有191条查询结果,搜索用时 31 毫秒
41.
Yuichi Yamaura Hitoshi Tojo Yasumasa Hirata Kenichi Ozaki 《Journal of Forest Research》2007,12(4):298-305
It is important to conserve forest-dependent organisms not only in broadleaved forests but also in plantation forests. We
examined how surrounding forest areas affect forest bird assemblages inhabiting conifer plantations and broadleaved forests
in a rural landscape in central Japan. Surrounding forest areas were measured separately as plantation area and broadleaved
forest area within 200 m of each sampling site. We used hierarchical partitioning to analyze the effects of surrounding forest
areas and stand structures (stand height and understory coverage) on the occurrence of four species groups. We especially
focused on mature forest users that are most sensitive to loss of broadleaved forests. Occurrence of mature forest users inhabiting
plantation sites was positively affected both by plantation area and broadleaved forest area whereas the occurrence of mature
forest users inhabiting broadleaved forests was affected by stand height only. These results suggest that surrounding forest
areas were more important to mature forest users in plantations than in broadleaved forests. To conserve mature forest users,
increasing surrounding forest areas are important in plantations whereas increasing stand heights would be effective in broadleaved
forests. 相似文献
42.
Saito J Miyamoto H Nakamura R Ishiguro M Michikami T Nakamura AM Demura H Sasaki S Hirata N Honda C Yamamoto A Yokota Y Fuse T Yoshida F Tholen DJ Gaskell RW Hashimoto T Kubota T Higuchi Y Nakamura T Smith P Hiraoka K Honda T Kobayashi S Furuya M Matsumoto N Nemoto E Yukishita A Kitazato K Dermawan B Sogame A Terazono J Shinohara C Akiyama H 《Science (New York, N.Y.)》2006,312(5778):1341-1344
Rendezvous of the Japanese spacecraft Hayabusa with the near-Earth asteroid 25143 Itokawa took place during the interval September through November 2005. The onboard camera imaged the solid surface of this tiny asteroid (535 meters by 294 meters by 209 meters) with a spatial resolution of 70 centimeters per pixel, revealing diverse surface morphologies. Unlike previously explored asteroids, the surface of Itokawa reveals both rough and smooth terrains. Craters generally show unclear morphologies. Numerous boulders on Itokawa's surface suggest a rubble-pile structure. 相似文献
43.
The purpose of this study is to confirm objectively by an instrumental measurement if there is less eye fatigue in VDT work
when using a wood rim covered display than when using a plastic housing display. The subjects were 26 graduate and undergraduate
university students. Each subject did the same 60-min VDT activity with both a plastic housing and wood-covered display. Before
and after VDT activity, each subject’s near-point accommodation distance was measured by a near-point ruler. As a result,
it was confirmed that variation rate of the near-point accommodation distance by the VDT work with the wood-covered display
was smaller than with the plastic housing display. From sensory tests, progression of subjective symptoms such as eye pain
and headache was less with the wood-covered display than with the plastic housing display. 相似文献
44.
Namikawa K Maruo T Honda M Hirata H Lynch J Madarame H 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(1):67-70
Gingival mass lesions developed when cyclosporine was administered for 600 days to a female, 7-year-old, longhaired dachshund diagnosed with intractable immune-mediated hemolytic anemia (IMHA). Histopathology indicated hyperplastic suppurative gingivitis. As the anemia improved, the dosage of cyclosporine A (CsA) was markedly decreased, and the mass lesions decreased in size and disappeared, thus suggesting that the mass lesions were an adverse reaction to CsA. 相似文献
45.
Okada K Nakae N Kuramochi K Yin SA Ikeda M Takami S Hirata T Goryo M Numakunai S Takeshima SN Takahashi M Tajima S Konnai S Onuma M Aida Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(12):1231-1235
Sheep were inoculated with high tax coded pBLV-IF (H group, Nos.1-5) of bovine leukemia virus (BLV), wild tax coded pBLV-IF (W group, Nos. 6-11), or control plasmid (C group, Nos. 12-14). During the observation period (4 to 46 months), 5 of 5 cases in H group and 3 of 6 cases (Nos. 6, 7, 9) in W group became positive for gp 51. Only 1 case in H group became leukemic, and one case each of H and W groups developed lymphoma. In No. 3, lesions were found in multiple organs including the lymph nodes, gastrointestinal tract following abomasum, and heart. In No. 6, lesions of lymphoma were found only in the jejunum and heart. Morphologically, small to middle-sized lymphocytic neoplastic (NP) cells were found in both cases, but lymphoblastic NP cells were found only in No. 3. By immunohistochemical examination, the phenotypes of NP cells were determined as CD1-, CD4-, CD5- -, CD8alpha-, sIgM+, lambda light chain+, B-B4+, MHC class II+ in both case. The results of this study indicate that inoculation of pBLV-IF can induce lymphocytic and lymphoblastic leukemia/lymphoma in sheep. Additionally, it is suggested that the expression rate of tax gene is not associated with the development of leukemia/lymphoma in sheep experimentally inoculated with pBLV-IF. 相似文献
46.
Sang-gun ROH Yeon-hee HONG Daisuke HISHIKAWA Hiroaki TSUZUKI Hisae MIYAHARA Yukihiko NISHIMURA Chizu GOTO Yasuki SUZUKI Ki-choon CHOI Hong-gu LEE Shinichi SASAKI 《Animal Science Journal》2005,76(4):381-386
Ghrelin and growth hormone secretagogues receptor (GHS‐R or ghrelin receptor) have been reported as being one of the factors of adipogenesis in adipocytes. To investigate the involvement of ghrelin and GHS‐R in adipocytes, the effect of the GHS‐R antagonist, [D‐Lys‐3]‐GHRP‐6 (His‐D‐Trp‐D‐Lys‐Trp‐D‐Phe‐Lys‐NH2), on the process of adipogenesis in ovine and rat adipocytes was evaluated. [D‐Lys‐3]‐GHRP‐6 (10?7 mol/L) significantly inhibited adipogenic differentiation of ovine and rat preadipocytes prepared from adipose tissues. The level of peroxisome proliferator activated receptor (PPAR)‐γ2 mRNA, an adipogenic marker, was decreased during the differentiation of adipocytes treated with [D‐Lys‐3]‐GHRP‐6 for 10 days. Ghrelin stimulated adipogenesis, also causing an increment of glycerol‐3‐phosphate dehydrogenase and upregulation of PPAR‐γ2. Furthermore, the antilipolytic effect of ghrelin was attenuated by treatment with [D‐Lys‐3]‐GHRP‐6 in both types of isolated adipocytes. Overall, the results of the present study highlight that GHS‐R in adipogenesis can be blocked by treatment with [D‐Lys‐3]‐GHRP‐6. 相似文献
47.
Takuya Wada Hiyori Monden Sachiko Isobe Kenta Shirasawa Takayuki Sueyoshi Chiharu Hirata Miyuki Mori Shiro Nagamatsu Yoshiki Tanaka 《Breeding Science》2021,71(4):456
Male sterility is one of the reproductive isolation systems in plants and quite useful for F1 seed production. We previously identified three independent quantitative trait loci (QTLs) for male sterility of cultivated strawberry, Here, we identified the specific subgenomes in which these QTLs are located by QTL-seq approach. QTLs qMS4.1, qMS4.2, and qMS4.3 were mapped separately in subgenomes Fvb4-4, Fvb4-3, and Fvb4-1, respectively, in ‘Camarosa’ genome assembly v. 1.0.a1. Candidate regions of qMS4.1 and qMS4.3 were clearly detected around 12–26 Mb in Fvb4-4 and 12–14 Mb in Fvb4-1, respectively; those of qMS4.2 were fragmented in Fvb4-3, which suggests that some scaffolds were incorrectly assembled in Fvb4-3. qMS4.3 was mapped to chr4X1 of ‘Reikou’ genome assembly r2.3, and qMS4.1 and qMS4.2 were both mapped to chr4Av, which indicates that differentiation of the subgenomes in which both QTLs are located was insufficient in ‘Reikou’ r2.3. Although ‘Camarosa’ genome assembly v. 1.0.a1 is an unphased map, which merges homologous chromosomes into one sequence, ‘Reikou’ genome assembly r2.3 is a phased map, which separates homologous chromosomes. QTL mapping to different reference genomes clearly showed the specific features of each reference genome, and that using different kinds of reference map could accelerate fine mapping and map-based cloning of certain genes of cultivated strawberry. 相似文献
48.
Mingzhu He Yanlian Zhou Weimin Ju Jingming Chen Li Zhang Shaoqiang Wang Nobuko Saigusa Ryuichi Hirata Shohei Murayama Yibo Liu 《Journal of Forest Research》2013,18(1):31-40
Gross primary productivity (GPP) is a major component of carbon exchange between the atmosphere and terrestrial ecosystems and a key component of the terrestrial carbon cycle. Because of the large spatial heterogeneity and temporal dynamics of ecosystems, it is a challenge to estimate GPP accurately at global or regional scales. The 8-day MODerate resolution Imaging Spectroradiometer (MODIS) GPP product provides a near real time estimate of global GPP. However, previous studies indicated that MODIS GPP has large uncertainties, partly caused by biases in parameterization and forcing data. In this study, MODIS GPP was validated using GPP derived from the eddy covariance flux measurements at five typical forest sites in East Asia. The validation indicated that MODIS GPP was seriously underestimated in these forest ecosystems of East Asia, especially at northern sites. With observed meteorological data, fraction of photosynthetically active radiation absorbed by the plant canopy (fPAR) calculated using smoothed MODIS leaf area index, and optimized maximum light use efficiency (ε max) to force the MOD17 algorithm, the agreement between predicted GPP and tower-based GPP was significantly improved. The errors of MODIS GPP in these forest ecosystems of East Asia were mainly caused by uncertainties in ε max, followed by those in fPAR and meteorological data. The separation of canopy into sunlit and shaded leaves, for which GPP is individually calculated, can improve GPP simulation significantly. 相似文献
49.
Dickeya dadantii (syn. Erwinia chrysanthemi) is a causal agent of soft-rot diseases on many crops. Here, we characterized a gene belonging to the major facilitator superfamily
(MFS), which is involved in the symport, antiport, or uniport of various substrates, and the survival and virulence of many
Gram-negative bacterial animal pathogens, for the possible involvement in the plant pathogenicity of D. dadantii. A marker-exchange mutant of this gene (mfsX) was constructed that had decreased maceration ability in Chinese cabbage, potato, and chicory. Observation with electron
microscopy showed greatly reduced numbers of flagella per cell. This mutant had a significant reduction in swimming and swarming
motility and a severe reduction in formation of biofilm. Because these phenotypes have been shown to be involved in plant
pathogenicity of D. dadantii, mfsX seems to play an important role in pathogenesis of D. dadantii 3937 by its involvement in the expression of these pathogenicity-related phenotypes. 相似文献
50.