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171.
Atsushi Ohkawa Noriko Ishikawa-Suehiro Seiichi Okuda Tomohide Natsuaki 《Journal of General Plant Pathology》2008,74(6):434-437
An infectious full-length cDNA clone of Chrysanthemum virus B (CVB, genus Carlavirus), was constructed. Four cDNA fragments covering the whole genome of CVB-S were cloned between the Cauliflower mosaic virus 35S promoter and the nopaline synthase (NOS) terminator. Chrysanthemum and garland chrysanthemum were inoculated with the
constructed plasmid, named pCVB, using a gene gun system. As is the case in wild-type, CVB-infected plants, no visible symptoms
were observed on plants inoculated with pCVB; however, western blotting and electron microscopy indicated the presence of
the progeny virus of pCVB. pCVB could be a useful tool for analyzing the functions of carlaviral proteins. 相似文献
172.
Faruq Ahmed Yasuyuki Koike Carlos Augusto Strüssmann Seiichi Watanabe 《Aquaculture International》2013,21(5):969-986
Effect of stocking density was studied in three abalone species Haliotis discus discus (HDD), H. gigantea (HG), and H. madaka (HM) and their hybrids [HDD × HM, HM × HG and HG × HM, mother first] by rearing individually marked abalones for 217 days at low (22 % of available surface area; LD), medium (53 %; MD), and high (126 %; HD) densities. Feeding rate (FR) and feed conversion rate were observed by measuring the amount of feed ingested at an interval of 2–3 days. Reduction of growth rate with the increment of density was found in all three species [Specific growth rate in weight (G W ) HDD, LD: 0.121, MD: 0.093, HD: 0.069; HM: 0.12, 0.082, 0.061; HG: 0.254, 0.222, and 0.131] and the hybrids HDD × HM (0.18, 0.109, 0.108). The medium density produced the highest growth rates in HM × HG and HG × HM hybrids (0.284, 0.342, 0.28). A growth spurt was observed in all three species and hybrids in the last 44 days of rearing. FR varied from 0.72 to 7.97 % body weight and decreased with the increase in density in all species and hybrids. The results indicate differences in density thresholds for the three abalone species and their hybrids suggesting requirement of different aquaculture management strategies for them. 相似文献
173.
To examine the behavior of monolignol and monolignol glucosides in lignin biosynthesis, pentadeutero[9-D(2), 3-OCD(3)]coniferyl alcohol and pentadeutero[9-D(2), 3-OCD(3)]coniferin were synthesized and fed to growing Eucalyptus camaldulensis and Magnolia kobus. The differences in the incorporation patterns of these labeled precursors were studied using gas chromatography-mass spectrometry (GC-MS). Both precursors were incorporated into lignin, but the labeled coniferyl alcohol was incorporated more directly, resulting in a high proportion of pentadeutero-labeled guaiacyl and syringyl units in newly formed xylem, while labeled coniferin tended to be incorporated in lignin as tetradeutero units, especially in syringyl lignin in both trees. However, the incorporation efficiencies of the precursors into syringyl lignin were higher in Magnolia than in Eucalyptus, and the ratios of tetradeutero to pentadeutero in guaiacyl lignin were lower in Magnolia than in Eucalyptus when the trees were fed coniferin. 相似文献
174.
稀释对CO掺氢混合燃料燃烧与排放性能的影响 总被引:1,自引:0,他引:1
在一台转速固定的火花点火发动机上进行了CO2稀释对CO掺氢混合燃料的燃烧及排放性能影响的试验研究.结果表明,氢气较快的燃烧速度弥补了由于其热值较低造成的对平均有效压力的影响,使得在每个当量比条件下平均有效压力基本保持不变.同时,掺氢对提升热效率及燃烧稳定性、改善CO以及NOx排放都有显著作用.适当的CO2稀释对平均有效压力和热效率的影响均不明显,而NOx排放水平则显著下降.但是过高的稀释率会导致部分燃烧,造成平均有效压力、热效率及CO排放的恶化. 相似文献
175.
Yusuke Hagiwara Takashi Osono Seiichi Ohta Agus Wicaksono Arisman Hardjono 《Journal of Forest Research》2012,17(1):51-57
Colonization of leaf litter by ligninolytic fungi and relationships between mass loss and chemical qualities of surface leaf
litter were examined in Acacia mangium plantations and adjacent secondary forests in southern Sumatra Island, Indonesia. Leaves were collected from eight A. mangium plantations of different ages and three secondary forests. Partly decomposed leaves beneath the surface leaf litter were
used to measure the bleached area which indicated colonization by ligninolytic fungi. Surface leaf litter was used to measure
initial chemical content and subjected to the pure culture decomposition test. The bleached area was greater in secondary
forests than in A. mangium plantations. Nitrogen content was higher in all the A. mangium plantations than in the secondary forests, and acid unhydrolyzable residue (AUR) content was generally higher in the A. mangium plantations than in the secondary forests. The bleached area of leaf litter was negatively correlated with nitrogen content
of surface leaf litter at all sites, indicating an inhibition of the colonization by ligninolytic fungi of leaves with higher
nitrogen content. In a pure culture decomposition test inoculating a ligninolytic fungus to surface leaf litter, mass loss
of leaves was negatively correlated with AUR content of surface leaf litter. Mass loss of leaves and AUR was not significantly
related to nitrogen content. These results suggested that higher nitrogen content in A. mangium leaf litter had a negative effect by colonization of ligninolytic fungi, but the effect of high N in A. mangium leaf litter on the decomposition of leaf litter and AUR remained unsolved. 相似文献
176.
Peripheral mononuclear cell response in Japanese black calves after oral administration of IFN-alpha
Ohtsuka H Tokita M Takahashi K Masui M Kohiruimaki M Hayashi T Ando T Watanabe D Kawamura S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(10):1063-1067
To investigate the effects of oral administration of an interferon (IFN)-alpha drug on the immune reaction of healthy Japanese Black (JB) calves, peripheral leukocyte populations and their ability to produce cytokine mRNA were analyzed after oral administration of IFN-alpha. Fourteen calves fed in one herd were divided into two groups; seven calves were orally administered 0.1 g/day of IFN-alpha from the day of birth to day 5 on each day (group 1, N=7), and the other seven calves were used as the control (group 2, N=7). Blood samples were collected from the jugular veins of all calves before administration and in weeks 1, 2, 4, 8, and 16 after birth. The number of MHC class II+CD14+ monocytes in the leukocytes population of group 1 increased gradually after birth, and significantly higher numbers were detected in week 4 compared with group 2. MHC class II-CD14+ monocytes in group 1 peaked in week 1, and a significant increase was detected compared with group 2. The level of IL-12 in the cytokine mRNA of group 1 increased gradually between weeks 1 and 2, and a significantly higher level of IL-12 was found compared with group 2. These results suggest that oral administration of IFN-alpha induces activation of the monocyte functions in JB calves. 相似文献
177.
178.
3维图像处理系统在稻米品质检测中的应用研究 总被引:12,自引:7,他引:12
侯彩云 Seiichi Oshit Yasuhisa Seo Yoshinori Kawagoe Toru Torii Kenichi Kudoh Toshiro Higuchi Gabsoo Do 《农业工程学报》2001,17(3):92-95
利用微切片3维图像处理系统对稻米的品质特性进行了探索性的研究。结果表明,借助于3维可视化技术,可以对稻谷的外观品质、营养品质及蒸煮品质等进行更为直观且客观的观察与测定。尤其是在营养成分分布密度的评价、心白米内部组织的分析、蒸煮过程中组织结构变化的观测等方面,取得了传统研究方法难以获得的结果。利用该系统对垩白度的定量化测定,为食品的定量形态学研究开辟了一条新的研究途径。 相似文献
179.
Togashi K Mawatari T Mitobe S Moriya S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(7):941-944
From April to July 2009, there was a high rate of reproductive losses in a 30-sow, farrow-to-finish swine herd in Yamagata Prefecture, Japan. Histopathological examinations of heart tissue from stillborn and preweaning piglets showed nonsuppurative, necrotizing lesions. Immunohistochemical staining and polymerase chain reaction analysis of myocardial lesions revealed the presence of porcine circovirus type 2 (PCV2) antigens and DNA in these tissues. Indirect immunofluorescence also showed that the PCV2 antibody positive rate in the sows was higher in May 2009 than in December 2008. The results of this study suggest that PCV2 spread to this farm and caused a high rate of reproductive losses. 相似文献
180.