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排序方式: 共有459条查询结果,搜索用时 334 毫秒
451.
Makoto Kondo Randi Mulianda Masaya Matamura Toshiyuki Shibata Takashi Mishima Anuraga Jayanegara Naoto Isono 《Animal Science Journal》2021,92(1):e13530
Soluble sugars in feeds are important for ruminant production; however, performing numerous sugar analyses within a short period is a laborious task. Here, we developed a phenol-sulfuric acid (PSA) assay in a microplate format to quantify soluble sugars in ruminant feeds. This method is easy and quick and requires only a small quantity of harmful reagents. We found that assay measurements were not affected by the representative organic acids and sugar alcohol contained in feeds. The treatment of activated charcoal with ethanol extract prior to the PSA assay was effective in removing interfering compounds for a more accurate determination of soluble sugars in certain feeds. Furthermore, the inter-day and intra-day repeatability of the present method was acceptable. Hence, we conclude that the method developed in this study is suitable for routine analysis of soluble sugars content in ruminant feeds. 相似文献
452.
Hiroki Yamazaki Hiroshi Sasai Miyuu Tanaka Toshiyuki Tanaka Hidetaka Nishida Shunsuke Noguchi Mitsuru Kuwamura Hideo Akiyoshi 《Veterinary and comparative oncology》2021,19(1):123-131
This study aimed to determine a reliable therapeutic biomarker for localized small intestinal lymphoma (SIL) in dogs based on clinical and histopathological features. We retrospectively investigated 84 dogs with localized SIL, including 36 dogs receiving surgery and 48 dogs receiving chemotherapy. The dogs receiving surgery were divided into two subgroups: 18 dogs (group 1) with overall survival (OS) <120 days (median OS) and 18 dogs (group 2) with OS ≥120 days. Correspondingly, the dogs receiving chemotherapy were divided into 24 dogs (group 3) with OS <98 days (median OS) and 24 dogs (group 4) with OS ≥98 days. Clinical, haematological, histopathological and immunohistochemical analyses were comparatively evaluated among the four subgroups. There was no significant difference in OS between the surgery and chemotherapy groups. In dogs receiving surgery, the rate of Ki67‐positive cells was significantly increased in group 1 compared to group 2 and showed no significant difference between groups 3 and 4. In dogs receiving chemotherapy, the rate of O6‐methylguanine‐DNA methyltransferase (MGMT) was significantly higher in group 3 than in group 4 and showed no significant difference between groups 1 and 2. Additionally, our data showed that OS in dogs with higher Ki67 expression might be significantly increased by chemotherapy than by surgery, that of those with higher MGMT expression might be significantly increased by surgery than by chemotherapy, and Ki67 and MGMT were independent of each other. Indices of Ki67 and MGMT are suggested therapeutic biomarkers to determine the optimal first‐line treatment for localized SIL in dogs. 相似文献
453.
Water Movement Characteristics in a Multi-Soil-Layering System 总被引:2,自引:0,他引:2
Kuniaki Sato Tsugiyuki Masunaga Toshiyuki Wakatsuki 《Soil Science and Plant Nutrition》2005,51(1):75-82
The Multi-Soil-Layering (MSL) system consists of soil units arranged in a brick-like pattern that are surrounded by layers of zeolite or alternating particles with a homogeneous size that allow a high hydraulic loading rate. Characteristics of the changes in the water movement, hydraulic retention time (HRT) and system weight during the wastewater treatment in the MSL system were investigated using a laboratory-scale MSL system (D10 × W50 × H73 cm). As the loading rate increased from 1,000 to 5,500 L m−2 d−1 , wastewater preferentially flowed into the permeable layers in the MSL, which decreased the contact of the wastewater with the soil mixture layers. HRT was inversely related to the loading rate. HRT decreased from 20 to 1 h, as the loading rate increased from 250 to 6,000 L m−2 d−1 . As an indicator of the system condition, the weight variation of the system was determined during the wastewater treatment. When the weight was stable, input and output of wastewater and decomposition of organic matter appeared to be equilibrated. When the weight increased, the system started to clog. Due to clogging, the efficiency of COD and phosphorus removal decreased, while the efficiency of nitrate removal increased. 相似文献
454.
Yasuo Iimura Daichi Tanaka Seiya Nagao Nobuhide Fujitake Toshiyuki Ohtsuka 《Soil Science and Plant Nutrition》2020,66(3):415-420
ABSTRACT The stability of black soil carbon in the deep layers of Japanese volcanic ash soil (i.e., buried A horizons) is often explained by its unique chemical (molecular structure) and physical (associated with short-range-order minerals) recalcitrance. However, the stability of black soil C in buried A horizons may be changed by labile C supply for soil microbes. Here, we hypothesized that the mineralization of black soil C in buried A horizons of Japanese volcanic ash soil could be easily accelerated by a supply of labile C (i.e., a priming effect; PE). To test our hypothesis, we investigated the direction and magnitude of the PE with a buried A horizon in Japan using 13C-labeled glucose (2.188 atom %) in a short-term (21 days) incubation study. We also investigated the effect of mineral nitrogen (N), which could contribute to microbial activity in this incubation study. We found that a positive PE occurred by glucose supply with (182%) or without (181%) mineral N input over the 21-day incubation, and its values were very similar to the PE ratios previously reported in other deep soils. The estimated mean residence time (MRT) of black soil C considering PE was clearly accelerated by glucose supply, regardless of mineral N input, compared with the initial soil MRT. These results strongly support our hypothesis that the mineralization rate of black soil C in buried A horizons is easily accelerated by a labile C supply, and it also demonstrates important implications for the effects of global warming on buried A horizons (e.g., increased root exudation, fine root biomass supply, and N deposition) in Japanese volcanic ash soils. 相似文献
455.
456.
457.
M. Hirata N. Koga† H. Shinjo H. Fujita‡ G. Gintzburger J. Ishida§ A. Miyazaki§ 《Grass and Forage Science》2005,60(1):25-33
Field survey and satellite image processing methods were used to estimate the total available forage over an area of 95 034 ha in north‐eastern Syria, and to assess grazing impact on the area. The above‐ground plant biomass was measured by a quadrat method at three sites in each of eight vegetation classes. Available forage was measured by excluding woody parts of shrubs from the whole aerial plant parts. The total above‐ground plant biomass and available forage were estimated by extrapolating the measured point data to the whole target area using classified vegetation data by satellite image processing. Grazing impact was assessed by calculating the differences between the total available forage at the end of growing season and the end of dry season. The values for the estimated total available forage (s.e. of mean) in the area were 55 628 000 (12 920 000) kg DM and 30 007 000 (2 437 000) kg DM at the end of growing season and dry season respectively. Although the area of the cereal fields covered only 0·315 of the area, about 0·69 and 0·82 of the available forage existed in the harvested cereal fields at the ends of growing season and dry season respectively. The integration of cereal fields and rangeland is a normal land use system for livestock management in the area. The higher cover of herbaceous vegetation types showed higher grazing impacts which reduced the total available forage at the end of the growing season by 0·817 (0·199) at the end of the dry season. Although these dense herbaceous vegetation types could possibly produce more available forage, they would incur more intensive grazing impact. On the contrary, lighter grazing impact would occur with a higher cover of shrub vegetation types. The importance of maintaining plant cover over the rangeland area to protect the land against soil erosion is stressed. 相似文献
458.
Demura H Kobayashi S Nemoto E Matsumoto N Furuya M Yukishita A Muranaka N Morita H Shirakawa K Maruya M Ohyama H Uo M Kubota T Hashimoto T Kawaguchi J Fujiwara A Saito J Sasaki S Miyamoto H Hirata N 《Science (New York, N.Y.)》2006,312(5778):1347-1349
The locations of the pole and rotation axis of asteroid 25143 Itokawa were derived from Asteroid Multiband Imaging Camera data on the Hayabusa spacecraft. The retrograde pole orientation had a right ascension of 90.53 degrees and a declination of -66.30 degrees (52000 equinox) or equivalently 128.5 degrees and -89.66 degrees in ecliptic coordinates with a 3.9 degrees margin of error. The surface area is 0.393 square kilometers, the volume is 0.018378 cubic kilometers with a 5% margin of error, and the three axis lengths are 535 meters by 294 meters by 209 meters. The global Itokawa revealed a boomerang-shaped appearance composed of two distinct parts with partly faceted regions and a constricted ring structure. 相似文献
459.
Artificial potassium silicate fertilizer (PSF) is a typical slow-release potassium fertilizer. However, the exact minerals that are released by PSF and the nutrients that are made available to plants remain unclear. This study quantitatively investigated the behaviour of nutrients released from PSF by the batch-release test and their supply to plants by the plant growth tests, respectively, to determine the quantitative relationship between nutrients released from PSF and taken up by the plant. X-ray diffraction (XRD) analysis showed that kalsilite, åkermanite, and potassium–magnesium silicate were the most abundant crystalline minerals in PSF. The XRD peaks of åkermanite and potassium–magnesium silicate were absent after citric acid extraction at a liquid/solid ratio of 20 to 100 (CA20 and CA100). Magnesium-use efficiencies in PSF (11%) and residue treatments after ammonium acetate extraction (AC, 10%) were higher than those in residue treatments after CA20 (1.8%) and CA100 (6.0%). Potassium (%) released by AC in the batch-release test (4.5%) was compatible with the difference of potassium-use efficiencies between the treatments of PSF (21%) and the AC-residue (16%). Likewise, potassium (%) released by CA20 (8.8%) was lower than the difference of potassium-use efficiencies between the treatments of PSF (21%) and CA20-residue (7.9%). This study suggests that potassium is rapidly released from potassium–magnesium silicate in PSF and is readily available to plants. 相似文献