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排序方式: 共有626条查询结果,搜索用时 39 毫秒
71.
Tetsuya Inagaki Manfred Schwanninger Reina Kato Yohei Kurata Warunee Thanapase Pratuang Puthson Satoru Tsuchikawa 《Wood Science and Technology》2012,46(1-3):143-155
Density and fiber length belong to the parameters that are used by the pulping industry as indicators of wood quality for different industrial processes and final paper products. The feasibility of Fourier transform near-infrared (FT-NIR) spectroscopy for the non-destructive evaluation of fiber length and air-dry density of fast-growing E. camaldulensis from Thailand was investigated using 50 samples. NIR spectra taken from solid wood and air-dry density as well as fiber length were used for partial least squares (PLS) regression analyses. It is the first time that the fiber length of E. camaldulensis solid wood could be predicted with high accuracy and precision and that the ratios of performance to deviation (RPD) obtained are the first that fully fulfill the requirements of AACC Method 39-00 (AACC 1999) for screening in breeding programs (RPD?≥?2.5). The RPDs for cross-validation (test set validation) of the NIR-PLS-R models of 3.3 (3.8) for air-dry density and 3.5 (3.9) for fiber length allow drawing the conclusion that the models are at least applicable for screening in breeding programs as they lie in-between screening (RPD?≥?2.5) and quality control (RPD?≥?5). Even when 40% of the samples were removed in cross-validation of the air-dry density model, the RPD is 3.2, which confirms that the model is robust, stable, and well qualified for prediction. The good model statistics obtained in this study might be due to the fact that measurement sites for the measurement of NIR spectra, air-dry density, and fiber lengths were strictly coincided. 相似文献
72.
Sun J Sugiyama A Hisaka S Kato Y Takeuchi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(2):141-147
To clarfity whether polyunsaturated fatty acid (PUFA) oxidation is involved in the mechanism of acetaminophen (APAP)-induced apoptotic cell death, the production and localization of PUFA oxidation markers N(ε)-propanoyl-modified lysine, N(ε)-hexanoyl-modified lysine, 4-hydroxyhexenal-modified histidine and crotonaldehyde-modified lysine were evaluated in the development of APAP-induced liver injury. The immunoexpression of these markers in the liver was examined up to 24 hr post-APAP intraperitoneal injection in rats (1 g/kg body weight). The histopathological changes in the liver appeared 3 hr after APAP injection and became exacerbated with time. Proapoptotic protein Bax immunoreactivity was first detected in the degenerative hepatocytes 3 hr after the injection and areas positively immunostained for Bax reached a peak level at 6 hr, and then decreased at 12 and 24 hr. There was a significant increase in the TUNEL-positive rate at 12 and 24 hr. Immunohistological expression of all these oxidation markers was first detected in the degenerative hepatocytes 3 hr after the injection, and earlier than the occurrence of hepatocyte apoptosis. Immunohistochemical expression of these markers were observed in almost all degenerative hepatocytes 3-24 hr after APAP injection. Areas positively immunostained for these markers reached a peak level at 6 hr, and then decreased at 12 and 24 hr. The results thus suggest that the generation of PUFA oxidation markers may be the signature of early events preceding the induction of liver cell apoptosis and thus useful for early detection of oxidative stress-related liver cell injury. 相似文献
73.
Edamura K Kuriyama K Kato K Nakano R Teshima K Asano K Sato T Tanaka S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(7):923-927
We examined the proliferation capacity and neuronal differentiation potency of canine bone marrow stromal cells (BMSCs). In addition, the microstructures of neuron-like cells after neuronal differentiation were observed under a scanning electron microscope. Canine BMSCs grew to confluency at 10.0 ± 2.5 days, and 3.8 ± 2.1 × 10(6) BMSCs were collected in one passage. Approximately 65% of canine BMSCs changed to neuron-like morphology after neuronal differentiation, and nearly all neuron-like cells stained positive against neuron-specific enolase. In addition, microstructures such as the cellular organelles, filaments and growth cones of these cells bore a close resemblance to those of the original mature neurons. These results suggested that canine BMSCs might be capable of differentiating into neurons. 相似文献
74.
Bannai H Tsujimura K Kondo T Nemoto M Yamanaka T Sugiura T Kato T Maeda K Matsumura T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(6):791-795
The immunoglobulin G (IgG) subclass response was investigated in horses with or without pyrexia after natural infection with equine herpesvirus type 1 (EHV-1) in the field. All horses were kept at the training centers of the Japan Racing Association and were immunized with an inactivated EHV-1 vaccine before EHV-1 infection. An IgG subclass response dominated by IgGa and IgGb was induced in horses without pyrexia after EHV-1 infection. In contrast, horses that developed pyrexia showed increased IgGc and IgG (T) subclass production in addition to IgGa and IgGb. Although inactivated EHV-1 vaccines are considered to induce a mainly Th-2-biased response, these results indicated that the responses in horses inoculated with inactivated EHV-1 vaccine were not uniform, and that horses with a Th-1-biased response were likely to be protected from pyrexia. 相似文献
75.
Two broodmares were diagnosed with rupture of the urinary bladder. One mare revealed abnormalities post partum and the other associated with ante partum uterine torsion. The clinical symptoms included mild abdominal pain, anorexia, decreased urinary volume and increased peritoneal fluid. In one mare, based on the creatinine level of the peritoneal fluid and serum biochemical abnormalities, uroperitoneum was diagnosed. In the other mare, the bladder rupture was found during the celiotomy for surgical repair of uterine torsion that was diagnosed upon rectal examination. Surgery was performed without a urethral sphincterotomy. The vaginal floor was incised in a standing position and the bladder was diverted into the vagina in order to suture the tears located in the ventrocaudal aspect of the bladder. Both mares survived after treatment for uraemia. Bladder rupture, although uncommon, may affect peripartum mares. Approach to the ruptured bladder without urethral sphincterotomy in a standing position should be considered as a choice for surgical repair. 相似文献
76.
Masako Seki Makiko Chono Tsutomu Nishimura Mikako Sato Yasuhiro Yoshimura Hitoshi Matsunaka Masaya Fujita Shunsuke Oda Katashi Kubo Chikako Kiribuchi-Otobe Hisayo Kojima Hidetaka Nishida Kenji Kato 《Breeding Science》2013,63(3):309-316
The Ppd-A1 genotype of 240 Japanese wheat cultivars and 40 foreign cultivars was determined using a PCR-based method. Among Japanese cultivars, only 12 cultivars, all of which were Hokkaido winter wheat, carried the Ppd-A1a allele, while this allele was not found in Hokkaido spring wheat cultivars or Tohoku-Kyushu cultivars. Cultivars with a photoperiod-insensitive allele headed 6.9–9.8 days earlier in Kanto and 2.5 days earlier in Hokkaido than photoperiod-sensitive cultivars. The lower effect of photoperiod-insensitive alleles observed in Hokkaido could be due to the longer day-length at the spike formation stage compared with that in Kanto. Pedigree analysis showed that ‘Purple Straw’ and ‘Tohoku 118’ were donors of Ppd-A1a and Ppd-D1a in Hokkaido wheat cultivars, respectively. Wheat cultivars recently developed in Hokkaido carry photoperiod-insensitive alleles at a high frequency. For efficient utilization of Ppd-1 alleles in the Hokkaido wheat-breeding program, the effect of Ppd-1 on growth pattern and grain yield should be investigated. Ppd-A1a may be useful as a unique gene source for fine tuning the heading time in the Tohoku-Kyushu region since the effect of Ppd-A1a on photoperiod insensitivity appears to differ from the effect of Ppd-B1a and Ppd-D1a. 相似文献
77.
Japanese black pine (Pinus thunbergii) seedlings resistant to pine wood nematode (PWN; Bursaphelenchus xylophilus) are routinely selected in Japanese field inoculation trials. Correlations between morphological factors (such as height, stem diameter at ground level and number of branches on seedlings) and disease resistance were examined to improve the production efficiency of 1‐year‐old black pine seedlings for inoculation. Family relatedness and environmental conditions strongly affected seedling resistance; accordingly, logistic regression analysis was used to separate effects of these two variables. Height and stem diameter at ground level significantly correlated with disease resistance in seedlings inoculated with PWN. Because (a) interactions between stem diameter at ground level and environmental condition were significant and (b) height did not interact with any other factor, it was concluded that height of 1‐year‐old Japanese black pine seedlings independently correlated with PWN resistance. Thus, field inoculation tests should use tall seedlings to achieve enhanced survival rates. 相似文献
78.
Water shortages during the dry season threaten sustainable agricultural production in Nganjuk District, East Java, Indonesia. To mitigate this problem, farmers adopted conjunctive use of surface water and groundwater, but the sustainability of this practice has not been investigated. This study temporally and spatially assessed water allocation in Nganjuk District when conjunctive irrigation was used. In particular, the land cover, water balance, and irrigation well density (IWD) were analyzed using time series GIS and remote sensing data to obtain their temporal and spatial distributions. First, the land cover was analyzed to determine cropping intensity, and the water balance was analyzed temporally and spatially. IWD was introduced to facilitate the water balance analysis. Second, the land cover, water balance, and IWD results were overlaid. Third, the effectiveness of the IWD method, the magnitude of water shortages, and the sustainability of groundwater resources were considered. Temporal and spatial water shortages in irrigation blocks were observed during the dry season. The change of storage showed a surplus during the wet and early dry seasons and a shortage during the late dry season. The annual water balances indicated that the southern part had a surplus, and the northern part experienced water shortages, especially downstream of the Widas River. Conjunctive use during the late dry season was predominant and concentrated in the southern part (83% of southern blocks). IWD was appropriate for examining groundwater use trends and was effective for expressing average withdrawal data (R 2 = 0.87). 相似文献
79.
Koji Yamane Ranee C. Mabesa-Telosa Ryosuke Tajima Nino P. M. C. Banayo Yoichiro Kato 《植物养料与土壤学杂志》2019,182(1):28-30
Simple tools for diagnosing crop nutritional status are in great demand by agricultural extension staff, particularly in low‐fertility environments. We developed the first practical method for in situ diagnosis of phosphorus (P) nutrition in field‐grown cereal crops by using a handheld colorimeter. The concentration of P in extracts from fresh leaves of lowland rice grown under various P availabilities was closely correlated with that of oven‐dried leaves measured with the standard molybdenum‐blue method in the laboratory, over a range of values from 0.319 to 1.420 mg P g ?1 DW (r = 0.885**, n = 14). It takes only 3–5 min to estimate the P concentration of plant samples using the new technique. Although not as accurate as the laboratory method, the new method can easily detect P deficiency of rice in the field (and possibly other cereal crops) without requiring costly, off‐site equipment. Thus, extension staff and agronomists can easily adopt this technique. 相似文献
80.
Shimizu E Kato H Nakagawa Y Kodama T Futo S Minegishi Y Watanabe T Akiyama H Teshima R Furui S Hino A Kitta K 《Journal of agricultural and food chemistry》2008,56(14):5521-5527
A novel type of quantitative competitive polymerase chain reaction (QC-PCR) system for the detection and quantification of the Roundup Ready soybean (RRS) was developed. This system was designed based on the advantage of a fully validated real-time PCR method used for the quantification of RRS in Japan. A plasmid was constructed as a competitor plasmid for the detection and quantification of genetically modified soy, RRS. The plasmid contained the construct-specific sequence of RRS and the taxon-specific sequence of lectin1 (Le1), and both had 21 bp oligonucleotide insertion in the sequences. The plasmid DNA was used as a reference molecule instead of ground seeds, which enabled us to precisely and stably adjust the copy number of targets. The present study demonstrated that the novel plasmid-based QC-PCR method could be a simple and feasible alternative to the real-time PCR method used for the quantification of genetically modified organism contents. 相似文献