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101.
Yoshio Kijidani Tetsuya Hamazuna Satoshi Ito Ryushi Kitahara Shinsuke Fukuchi Nobuya Mizoue Shigejiro Yoshida 《Journal of Wood Science》2010,56(1):1-6
The lumber from sugi plantations in Japan displays large intra- and intertree variation in mechanical properties, even within
a stand. These variations seem to be induced by the effects of the characteristics of cultivars as well as the effects of
growth traits on mechanical properties. Therefore, the effects of growth traits on mechanical properties per cultivar need
to be precisely examined. In this study, we focused on the effects of growth traits, especially height-to-diameter ratio (H/D
ratio), on stem stiffness per cultivar. Sixteen cultivars were classified into three groups according to the relationships
between stem stiffness and growth traits. In cultivars that showed a close correlation between growth traits and stem stiffness,
it was assumed that stem stiffness could be controlled to a certain extent by silvicultural practices using the H/D ratio
as an indicator. In cultivars that showed a weak correlation between growth traits and stem stiffness, selecting cultivars
for the production of logs with higher mechanical properties seemed to be effective; in this study, Kumotoshi, Tanoaka, and
Edanaga were found to be suitable. Tree age and site index may be important factors for producing wood with higher mechanical
properties. 相似文献
102.
Ito D O'Brien TD Modiano JF 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(4):494-498
Background: Cytoplasmic fragments derived from fragile neoplastic lymphocytes are common in samples of lymph nodes collected from dogs with lymphoma. These cytoplasmic fragments interfere with accurate gating of target cells and quantification protocols used for flow cytometry because of their variable size and expression of lymphoid cell surface antigens on their membranes. Objective: The aim of this study was to develop a method to efficiently exclude cytoplasmic fragments from flow cytometric analysis of canine lymph nodes in which lymphoma was present. Methods: Single‐cell suspensions of neoplastic cells were prepared from biopsy samples and fine‐needle aspirates of lymph nodes from 23 dogs with lymphoma. Suspensions were stained using a violet laser‐excitable (405 nm) membrane‐permeable DNA‐binding fluorescent dye (DyeCycle Violet [DCV]), incubated with antibodies against CD3, CD5, CD21, CD22, and CD45, and then stained with 7‐amino‐actinomycin D (7‐AAD), an argon‐excitable (488 nm) membrane‐impermeable DNA‐binding fluorescent dye. Multiparameter flow cytometry was used for analysis based on selective uptake and laser‐activated fluorescence of these dyes. Results: Cytoplasmic fragments, which were DCV‐negative and CD45‐positive, and dead cells, which were positive for 7‐AAD, were efficiently separated from neoplastic cells. Conclusion: Staining with DCV is a useful method to improve flow cytometric gating methods and quantitative analyses of lymph node samples from dogs with lymphoma. 相似文献
103.
H. Hayama A. Ito T. Shimada Y. Kashimura 《The Journal of Horticultural Science and Biotechnology》2013,88(4):651-655
SummaryChanges in cellulose content and the accumulation of PpCesA1 mRNA, putatively encoding the catalytic subunit of cellulose synthase (CesA), were analysed in endocarp and mesocarp during endocarp hardening in peach fruit. The cellulose content of the endocarp was undetectable or very low [< 0.1 mg g–1 fresh weight (FW) of endocarp] until 48 d after full bloom (DAFB), but began to increase rapidly at 55 DAFB, when the endocarp had attained its maximum size, and reached 4.4 mg g–1 FW of endocarp at 85 DAFB. In contrast, the cellulose content of the mesocarp reached a detectable level (1.5 mg g–1 FW of mesocarp) at 34 DAFB, stayed at this level until 85 DAFB, but then was lower at 107 DAFB. PpCesA1 mRNA was detected in the endocarp throughout the hardening, but was undetectable in the mesocarp. It is suggested that PpCesA1 has a role in the rapid synthesis of cellulose in the secondary cell walls of endocarp tissue during hardening. 相似文献
104.
Background
Throughout Asia, including Japan, rice plants are cultivated in a wide range of areas from lowlands to highlands and are frequently exposed to fog, including acid fog. Some physiological studies have shown that acid fog can be a stress factor for plants. We analyzed the gene expression profiles of rice plants treated with artificially prepared simulated acid fog (SiAF) or simulated neutral fog (SiNF) for 1 or 7 days.Results
Microarray analysis results suggested that both the SiAF and the SiNF treatments induced the expression of genes involved in the defense and stress responses in rice plants. Induction of such genes was detected in plants treated with SiAF for 1 day, and the number of induced genes increased in plants treated with SiAF for 7 days. The genes for defense and stress responses were also induced by SiNF for 7 days, although they were not induced by SiNF for 1 day. The gene expression profiles of the SiAF-treated and the SiNF-treated plants were compared to those of plants treated with other stress factors. The comparison revealed that both SiAF and SiNF treatments have similar effects to biotic stresses and ozone stress. The genes encoding NADPH oxidase and germin, which function in apoplasts, were also induced by SiAF, SiNF and biotic stresses.Conclusions
These findings suggest that both the SiAF and the SiNF treatments may result in oxidative stress through the apoplastic production of reactive oxygen species. 相似文献105.
Takahashi S Hirai N Shirai M Ito K Asai F 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(7):953-956
The aim of this study was to examine the blood coagulation profiles of ferrets and compare them with those of rats. The ferret activated partial thromboplastin time (aPTT) was slightly longer than the rat aPTT. In contrast, the ferret prothrombin time and thrombin time were profoundly shorter than the corresponding rat values. The fibrinogen level in ferret plasma was 2 times higher than that in rats. Heparin prolonged all blood coagulation times in a concentration-dependent manner in both ferret and rat plasma. A significantly (P<0.01) higher concentration of heparin was required to double the aPTT in ferrets than rats. These blood coagulation data for ferrets will be useful in experimental animal studies. 相似文献
106.
Said AW Kodani M Usui T Fujimoto Y Ito T Yamaguchi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(4):545-548
Embryonated chicken eggs (ECEs) are routinely used to isolate equine influenza virus. Propagation of the virus in ECEs results in selection of variants. In the present study, we determined nucleotide sequences of entire coding regions of parent A/equine/Tottori/1/07 (H3N8) and its derivatives that have different passage histories in ECE. After 12 passages, nucleotide sequence analysis predicted 3 amino acid substitutions in hemagglutinin (HA; 2 in HA1 and 1 in HA2). The two amino acid substitutions in HA1 were located in the vicinity of the cell receptor-binding site. Three other amino acid substitutions were predicted in internal proteins, 1 in the M1, 1 in the NP and 1 in the PA. This is the first report showing mutations in the internal protein genes of equine influenza virus associated with adaptation to ECE. 相似文献
107.
Sano S Sugiyama K Ito T Katano Y Ishihata A 《Journal of agricultural and food chemistry》2011,59(11):6209-6213
Piceatannol is present in passion fruit (Passiflora edulis) seeds in high amounts. In this study, we isolated the second major polyphenolic compound of passion fruit seeds and identified it as scirpusin B, which is a dimer of piceatannol. We investigated the antioxidant activities and vasorelaxing effects of these polyphenols. Their antioxidant effects were measured using an in vitro 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, and their vasorelaxant effects were determined ex vivo in rat thoracic aorta. Both polyphenolic compounds exhibited potent antioxidant activities and significant vasorelaxant effects in endothelium-intact aortas. More specifically, scirpusin B exerted a greater antioxidant activity and vasorelaxant effect compared with that of piceatannol. Additionally, the vasorelaxation effects of the compounds were induced via the NO derived from the endothelium. This study provides the possibility that polyphenols in passion fruit seeds are effective against cardiovascular diseases (CVDs). 相似文献
108.
Hiroaki Samejima Motohiko Kondo Osamu Ito Takuhito Nozoe Takuro Shinano Mitsuru Osaki 《Soil Science and Plant Nutrition》2013,59(4):545-554
The objective of the present study was to identify the limiting factors in biomass productivity of new tropical rice lines (panicle weight type) by analyzing the relationship between root and shoot activity. Five field experiments using three new lines, IR65598-112-2, IR65600-42-5-2, and IR68544-29-2-1-3-1-2, and one of the highest-yielding indica rice varieties (panicle number type), IR72, were conducted at the International Rice Research Institute from 1997 to 2002. Specific absorption rate of N (SARN , mg N g-1 root dry weight d-1), specific stem sap exudation rate (sap exudation rate, g exudate g-1 root dry weight 12 h-1) and specific root respiratory rate (root respiratory rate, μmol O2 g-1 root dry weight h-1) were determined as indices of root activity. Relative growth rate (RGR, mg g-1 d-1) was used as an index of shoot activity. Compared with IR72, the new lines showed lower RGR and SARN values during the early growth stages. In contrast, during the late growth stages, these activities were higher in the new lines than in IR72. The SARB and sap exudation rate showed a linear correlation with RGR at successive growth stages, regardless of the genotypes and growth conditions. These findings indicated that active root-shoot interaction was maintained throughout the growth period in high-yielding tropical rice, including the new lines and IR72. Therefore, it was considered that SARN and the sap exudation rate are useful indices of root activity regulating RGR in the new lines. However, the root respiratory rate could not be used for selection, because the relationship between RGR and the root respiratory rate changed with the growth conditions. Our findings support the hypothesis that root and shoot activities during maturation are important factors affecting the productivity of the new lines, which have not yet been able to attain the targeted yield. 相似文献
109.
Hisashi Sato Akihiko Ito Akinori Ito Takashi Ise Etsushi Kato 《Soil Science and Plant Nutrition》2013,59(1):34-47
Although climate conditions primarily determine the distribution and functioning of vegetation, vegetation also influences climate via biophysical and biogeochemical features such as evapotranspiration, albedo, carbon cycling, trace gas emissions and the roughness of the land surface. Forecasts of rapid climate change during the next 100~200 years, fueled by an increase in greenhouse gases, have motivated the development of land surface models (LSMs) that predict changes in vegetation functions. Here, we review how these models have been developed and used to simulate interactive processes between climate and the land surface. Current limitations and future perspectives of the LSMs are also presented. 相似文献
110.
14C-labelled sodium bicarbonate and 15N-labelled ammonium sulfate were simultaneously vacuum-infiltrated into detached sunflower leaves, and the incorporation of 14C and 15N into free amino acids was chased during 60-min period in the light and in the dark. In the light, the ue specific activity of aspartic acid, alanine, serine and glycine rapidly increased for 5 min and thereafter decreased. On the other hand, that of gultamic acid continued to increase slowly during the entire 60-min period. In the dark, aspartic acid most actively incorporated 14C. The difference of changes in 14C specific activity between glutamic acid and other amino acids was also observed in the dark as in the light. These results suggest that the carbon skeleton of glutamic acid is synthesized from aspartic acid, alanine, serine and glycine. 15N content of glutamine was the highest of all amino acids investigated in the light, and it was followed by glutamic acid. alanine, aspartic acid, serine and glycine, in this order. In the dark, 15N content of glutamic acid fell remarkably and was lower than that of alanine up to 5 min. From these 15N tracer experiments, it is suggested that the incorporation of ammonium into glutamic acid is strictly dependent on light and that alanine incorporates ammonium by the direct amination besides the transamination from glutamic acid. 相似文献