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排序方式: 共有281条查询结果,搜索用时 31 毫秒
51.
Abstract – Video cameras inside underwater housings were used to record the spawning behaviour of a subspecies of the white‐spotted charr, the amemasu charr (Salvelinus leucomaenis leucomaenis) in the Tokimae and Onbetsu Rivers, Hokkaido, Japan. Unlike other Salvelinus species, in which females use lateral swings of their bodies to ventilate and distribute eggs over gravel crevices (undulating) immediately after spawning, female amemasu charr covered their eggs with beats of their tails (cover digging). Cover digging right after spawning has previously been documented in Salmo, Oncorhynchus and Parahucho. Phylogenetic analysis of postspawning behaviours in the Salmoninae indicated that (i) resting then covering the eggs is plesiomorphic for the group, (ii) undulating replaced resting in the ancestor of Salvelinus, (iii) cover digging was advanced in the behavioural sequence to occur immediately after egg deposition in the ancestor of Parahucho + Salmo + Oncorhynchus and in the amemasu. 相似文献
52.
Fisheries Science - The article "Bio-economic analysis of super-intensive closed shrimp farming and improvement of management plans: a case study in Japan", written by Junpei Shinji,... 相似文献
53.
Yoshihiro Katayama Yoko Mashino Nobuyuki Nishikubo Kaori Yoshitomi Ryo Funada Shinya Kajita 《Journal of Wood Science》2002,48(6):457-466
We have investigated the spatial regulation of the accumulation of enzymes involved in the biosynthesis of shikimate and lignin during differentiation of primary xylem from the apical meristem via procambium in hybrid aspen (Populus sieboldii x Populus grandidentata). Immuohistochemical staining revealed that, in the top part of shoots, lignification began in a single or just a few adjacent vessel elements and subsequently spread to neighboring cells. The spatial localization of 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase (DAHPS), which is one of the key enzymes in the shikimate pathway, was tightly correlated with the cell-specific deposition of lignin in the primary xylem. We also found that the spatial localization of enzymes in the general phenylpropanoid pathway and in the lignin-specific pathway was closely associated with the cell-specific deposition of lignin and the accumulation of DAHPS. Our data suggest that enzymes that act in the shikimate, general phenylpropanoid, and lignin-specific pathways are initially produced and function coordinately in a single or a few adjacent elements at the start of primary xylem development. 相似文献
54.
Study of crystalline behavior of heat-treated wood cellulose during treatments in water 总被引:1,自引:0,他引:1
The crystalline behavior of heat-treated wood cellulose treated at 85% relative humidity (RH), in water, or boiled in water after heat treatment was investigated. The normal increased crystallinity was significantly depressed for samples that were oven-dried and then treated in 85% RH or in water. In the case of boiling-water treatment, a more pronounced increased in crystallinity was initially observed, which then decreased gradually. The crystallinity decreased more than untreated wood for samples that were heat treated for long periods and was slightly higher than the decreased crystallinity from the beginning of the above two treatments. On the other hand, no significant change in crystallinity was observed for samples of increased crystallinity or decreased crystallinity that were treated under high-moisture conditions, for all three treatments. The results show that the crystalline state of wood cellulose heat treated under oven dry or high-moisture conditions behave differently if treated in water after heat treatment. Results suggested that the mechanism of crystallization might be different for samples that are subjected to heat treatment under oven-dry and high-moisture conditions. 相似文献
55.
Takahashi T Sugawara T Yamatsuta T Isogai M Natsuaki T Yoshikawa N 《Phytopathology》2007,97(10):1200-1206
ABSTRACT Apple latent spherical virus (ALSV) expressing yellow and cyan fluorescent proteins (ALSV-YFP and ALSV-CFP) was used to investigate the distribution of identical virus populations in coinfected plants. In Chenopodium quinoa plants inoculated with a mixture of ALSV-YFP and ALSV-CFP, fluorescence from YFP and CFP was always distributed separately in both inoculated and upper uninoculated leaves. Inoculation of each ALSV-YFP and ALSV-CFP to different leaves of a C. quinoa plant resulted in the separate distribution of each virus population among different upper leaves. When C. quinoa leaves were first inoculated with ALSV-CFP and then ALSV-YFP was reinoculated into the same leaves at various times after the first inoculation, ALSV-YFP infected only tissues where ALSV-CFP infection had not been established. The spatial separation was also found in Nicotiana benthamiana leaves coinoculated with Bean yellow mosaic virus (BYMV)-YFP and BYMV-CFP. In contrast, both YFP and CFP fluorescence signals were observed in the same tissues of N. benthamiana leaves mixed infected with ALSV-YFP and BYMV-CFP. YFP fluorescence from ALSV-YFP in mixed-infected leaves was brighter and longer than in leaves infected with ALSV-YFP singly. 相似文献
56.
Mizukami Y Kohata K Yamaguchi Y Hayashi N Sawai Y Chuda Y Ono H Yada H Yoshida M 《Journal of agricultural and food chemistry》2006,54(19):7370-7377
Optimization of the solid-phase extraction cleanup procedure enabled the GC-MS analysis of acrylamide in tea samples without the interference of bromination by tea catechins. Although polyvinylpolypyrrolidone (PVPP) is available for removing tea catechins from tea extract, the peaks derived from PVPP had the same retention time as brominated acrylamide in mass chromatograms obtained by GC-MS. A considerable amount of acrylamide was formed at roasting temperatures of > or =120 degrees C; the highest acrylamide level was observed when tea samples were roasted at 180 degrees C for 10 min. Higher temperatures and longer processing times caused a decrease in the acrylamide content. Furthermore, an analysis of 82 tea samples showed that rather than the reducing sugar content, the asparagine content in tea leaves was a significant factor related to acrylamide formation in roasted products. The acrylamide level in roasted tea products was controlled by asparagine in the presence of reducing sugars. 相似文献
57.
Kakizaki T Hamada N Funayama T Sakashita T Wada S Hohdatsu T Natsuhori M Sano T Kobayashi Y Ito N 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(12):1269-1273
High linear energy transfer (LET) heavy charged particles have previously been applied clinically to human cancer radiotherapy because of their excellent physical properties of selective dose distribution and higher relative biological effectiveness (RBE) for human; however, such an approach has yet to be applied to cat patients. The present study investigates the biological effectiveness of low-LET gamma-rays (0.2 keV/micro m) compared to high-LET carbon ions (114 keV/micro m) in feline T- lymphocyte FeT-J cells. Clonogenic survival analysis revealed that the RBE value of carbon ions was 2.98 relative to a 10% survival dose (D(10)) by gamma-rays, and that the inactivation cross-section in cells exposed to gamma-rays and carbon ions was 0.023 and 38.9 micro m(2), respectively. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) analysis revealed that TUNEL-positive frequency in carbon-irradiation cells is higher than for gamma-irradiated cells against exposure to the same physical doses, but that very little difference in TUNEL-positive frequency is observed between cells exposed to the respective D(10) dose of gamma-rays. Our data thus indicate that carbon ions are more effective for cell killing than gamma-rays at the same physical doses, but kill cells to an extent that is comparable to gamma-rays at the same biological doses. Carbon ion radiotherapy is therefore a promising modality for cat patients. 相似文献
58.
To H Sato H Tazumi A Tsutsumi N Nagai S Iwata A Nagano T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(7):949-953
The objective of the present study was to characterize Erysipelothrix sp. strains from recent erysipelas outbreaks in Japan. Eighty-three (100%) strains were identified as E. rhusiopathiae, based on serotyping and spaA PCR. Fifty (60.3%), 5 (6.0%), and 28 (33.7%) strains were isolated from animals with acute, subacute and chronic outbreaks, respectively, of which 79 (95.2%), 1 (1.2%), and 3 (3.6%) belonged to serotypes 1a, 2a, and untypeable, respectively. Fifteen strains (including 3, 2, and 10 from acute, subacute, and chronic cases, respectively) were sensitive to acriflavine, and showed high levels of virulence in mice; of which strains from acute cases, and from subacute and chronic cases killed 100%, and 80 to 100% mice, respectively at challenge doses of 10(2) CFU per mouse. Based on sequence analysis of a 432-bp hypervariable region in spaA gene, 83 strains could be divided into 3 groups: (i) group 1 (3 strains of serotype 1a) had Ala-195 and Ile-203; (ii) group 2 (76 strains of serotype 1a and 3 of untypeable) had Asp-195 and Met-203; and (iii) group 3 (one strain of serotype 2a) had Asn-195 and Ile-203. The results of the present study suggest that the serotype 1a strains belonging to the group 2 might be widespread in pig populations in Japan. 相似文献
59.
60.
Masamichi Isogai Mari Yoshida Hiroyuki Imanishi Nobuyuki Yoshikawa 《Journal of General Plant Pathology》2012,78(5):360-363
Severe yellowing of leaves was observed on red raspberry in Akita Prefecture. When inoculated with sap from symptomatic raspberry leaves, Chenopodium quinoa plants developed chlorotic ringspot and mottling that are typical of raspberry bushy dwarf virus (RBDV) infection. In western blot analysis, an antibody to the coat protein (CP) of RBDV reacted against ca. 30-kDa protein specific to the diseased trees. In RT-PCR testing for RBDV, single DNA fragments were amplified from total RNA samples of the diseased trees. The nucleotide sequences of the DNA fragments covering the entire CP region revealed 87–97?% identities with those of RBDV isolates. 相似文献