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排序方式: 共有462条查询结果,搜索用时 15 毫秒
431.
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
432.
Expression of myogenic regulating factors, Myogenin and MyoD, in two canine botryoid rhabdomyosarcomas 总被引:1,自引:0,他引:1
Kobayashi M Sakai H Hirata A Yonemaru K Yanai T Watanabe K Yamazoe K Kudo T Masegi T 《Veterinary pathology》2004,41(3):275-277
Myogenin and MyoD regulate the development of skeletal muscle, and their expressions are specific to the stages of myogenesis. Therefore, these myogenic regulatory proteins could be considered as sensitive and specific markers for rhabdomyosarcoma. In this report we investigated the immunohistochemical reactivities of myogenin and MyoD in two canine bladder botryoid rhabdomyosarcomas that were different in the degree of differentiation. MyoD was stained in the Ki-67 antigen-positive undifferentiated mesenchymal cells, which had proliferative activity similar to myoblasts differentiated from mesoblasts. In contrast, multinucleated neoplastic cells were positive for myogenin and alpha-sarcomeric actin but not for Ki-67 antigen, similar to the myotubes differentiated from myoblastic cells. The expressions of myogenin and MyoD were closely correlated to the histologic features of myogenic neoplastic cells. 相似文献
433.
Hiroki Takakuwa Tetsu Yamashiro Mai Q. Le Lien S. Phuong Hiroichi Ozaki Ryota Tsunekuni Tatsufumi Usui Hiroshi Ito Tsuyoshi Yamaguchi Toshihiro Ito Toshiyuki Murase Etsuro Ono Koichi Otsuki 《Comparative immunology, microbiology and infectious diseases》2013
Due to concerns that wild birds could possibly spread H5N1 viruses, surveillance was conducted to monitor the types of avian influenza viruses circulating among the wild birds migrating to or inhabiting in northern Vietnam from 2006 to 2009. An H5N2 virus isolated from a Eurasian woodcock had a close phylogenetic relationship to H5 viruses recently isolated in South Korea and Japan, suggesting that H5N2 has been shared between Vietnam, South Korea, and Japan. An H9N2 virus isolated from a Chinese Hwamei was closely related to two H9N2 viruses that were isolated from humans in Hong Kong in 2009, suggesting that an H9N2 strain relevant to the human isolates had been transmitted to and maintained among the wild bird population in Vietnam and South China. The results support the idea that wild bird species play a significant role in the spread and maintenance of avian influenza and that this also occurs in Vietnam. 相似文献
434.
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
435.
Xiaoniu Xu Yoshihiro Tokashiki Eiji Hirata Tsutomu Enoki Kangoro Nogami 《Journal of Forest Research》2000,5(3):151-156
Patterns of litterfall and nutrient input in a subtropical evergreen broad-leaved forest in northern Okinawa, Japan, were
studied during May, 1996–April, 1999. The mean annual rate of litterfall in the five sampling plots ranged from 6.84 to 8.93
Mg ha−1 yr−1, of which 63.3–68.5% were leaves; 22.4–29.1% woody parts (including branches < 5.0 cm in diameter and bark); 2.8–5.0% sexual
organs and 4.6–6.3% miscellaneous material. Significant differences were found among plots and among years. Significantly
monthly differences pronounced seasonal patterns in litterfall were observed. Total litterfall and leaf litter showed negative
correlations with relative basal area of the dominant species,Castanopsis sieboldii; and showed positive correlations with mean height of the stands. The dominant species,C. sieboldii produced an average of 2.36 Mg ha−1 yr−1 of leaf litter, which covered 30.5% of the annual litter production, and the nutrient input from those litterfall contributed
32.3, 28.3, 30.2, 22.2, 32.5, and 30.5% of total N, P, K, Ca, Mg, and Na, respectively. Nutrient use efficiency in litter
production was high, especially for P and K compared with other broad-leaved forests in Japan indicating that P and K may
be limiting in Okinawan evergreen broad-leaved forest. 相似文献
436.
437.
Productivity of Bahiagrass Pastures in South-western Japan: Synthesis of Data from Grazing Trials 总被引:1,自引:0,他引:1
M. Hirata Y. Ogawa N. Koyama K. Shindo Y. Sugimoto M. Higashiyama S. Ogura K. Fukuyama 《Journal of Agronomy and Crop Science》2006,192(2):79-91
This study examined the rate of herbage production and herbage quality of bahiagrass (Paspalum notatum Flügge) using data from five grazing trials in the low‐altitude region of Kyushu, south‐western Japan, in an effort to (a) evaluate productivity of bahiagrass pastures, (b) analyse its relationship to meteorological, vegetational and managerial variables, and (c) obtain implications for better management of bahiagrass pastures. The rate of herbage production, ranging from ?56 to 213 kg DM ha?1 day?1, tended to increase from spring (April–May) to mid‐summer (July) and decrease thereafter. The rate was expressed by a multiple regression equation where nitrogen fertilizer rate, air temperature, rainfall and herbage mass had positive effects. Dry matter digestibility (DMD) and crude protein (CP) concentration of herbage were in the range of 471–727 and 84–161 g kg?1 DM respectively. DMD was expressed by a regression equation where the day number from 1 April and herbage mass had negative effects, and the sampling height and nitrogen rate had positive effects. CP concentration was expressed by an equation showing a positive effect of nitrogen rate and a negative effect of herbage mass. The results indicate that management of bahiagrass pastures should aim at maintaining herbage mass closely above the critical level below which intake by grazing animals is restricted, in order to increase quality and ensure quantity. This is particularly important when nitrogen fertilizer is applied. 相似文献
438.
Shortage of organic matter hinders agricultural production in the Sahel, and this lack of enough organic matter is more severe for peri-urban horticulture, which depends heavily on it. Alternative sources of organic matter that offer new options for peri-urban horticulture can help reduce the potential for conflict over finite resources between traditional crop production and peri-urban horticulture. Both agronomic and economic evaluations of an organic amendment called heated sewage sludge (HSS) were conducted in the research station of International Crops Research Institute for the Semi-Arid Tropics (ICRISAT)-Niamey, Niger, West Africa. For this study, HSS, a material imported from Japan, applied at a dosage application equivalent to 20.0 kg 100 m−2 on lettuce fields led to production levels as high as those of conventional methods, and the yield became even higher than those of conventional methods when the dosage was increased to 50.0 kg 100 m−2 and 100.0 kg 100 m−2. Even though HSS was imported, its benefits outweighed its cost, as evidenced by the positive net returns. Since profitability in peri-urban horticulture is much higher than that of traditional crop production, the results of this study imply that if adopted, the use of HSS can lead to increased availability of organic matter for traditional cropping systems. 相似文献
439.
To clarify the inducing mechanism of kerf deviation caused by unsymmetrical set of the handsaw, we hypothesized that the moment
on the bottom edge of the saw blade, which is generated by the unsymmetrical set on handsaw teeth, bends the saw blade and
this deformation should be one factor of the kerf deviation. To verify this hypothesis, the bend of a saw blade was examined
by experiment and by calculation. In the experiments, a model tooth was attached to an actual handsaw. In the calculations,
a saw model with a rectangular prism as the model tooth was analyzed by the finite element method. Loads were applied on the
model tooth or the rectangular prism. From both the experiments and the calculations, the following results were obtained:
(1) the deformation of the handsaw was caused by the unsymmetrical set in the length direction and the height direction of
the saw blade; (2) the deformation and the inclination of the blade was larger at the front part of the saw than at the butt
part; and (3) comparing the saw handle fixing conditions, the kerf deviation in the sawing line was supposed to be larger
in the free handle condition and that kerf deviation in the depth direction was larger in the fixed handle condition. Based
on the above results, it is apparent that one of the kerf deviation mechanisms originated from unsymmetrical set on the saw
teeth.
Part of this report was presented at the 54th Annual Meeting of the Japan Wood Research Society, Sapporo, Japan, August 2004. 相似文献
440.
Yasumasa Hirata Ryuichi Tabuchi Pipat Patanaponpaiboon Sasitorn Poungparn Reiji Yoneda Yoshimi Fujioka 《Journal of Forest Research》2014,19(1):34-41
Mangroves play important roles in providing a range of ecosystem services, mitigation of strong waves, protection of coastlines against erosion, maintenance of water quality, and carbon sink in the context of global warming. For trees in mangrove forests in southern Ranong Province, Thailand, we investigated the allometric relationship between crown area derived from high-resolution satellite data and stem diameter and used the resulting model to estimate aboveground biomass. We used QuickBird panchromatic and multispectral data acquired for the study area on 15 October 2006 as the high-resolution satellite data. Individual tree crowns were extracted from the satellite image of panchromatic data by using the watershed method, and the species were identified by using the maximum-likelihood method for the multispectral data. Overall classification accuracy for species identification was 88.5 %. The biomass derived from our field survey was plotted against aboveground biomass in the sample plots, estimated from the QuickBird data. The regression line through the origin between the satellite-estimated biomass and biomass based on the field data had a slope of 1.26 (R 2 = 0.65). Stand aboveground biomass estimated from the high-resolution satellite data was underestimated because of a lack of data on the biomass of suppressed trees and inappropriate segmentation of crowns of large trees into two or more trees. 相似文献