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1.
2.
Rina Yamane Makoto Tanaka Nao Kikugawa Hideki Yasui Kenta Takei Miwa Harada Shinya Kaneda 《Journal of toxicologic pathology》2021,34(1):127
The pathological effects of copper deficiency (COD) are well known. However, the pathogenesis of cardiomyopathy resulting from COD remains unclear. In this study, aimed to elucidate the pathogenesis of COD-induced cardiomyopathy by examining the morphology of the cardiovascular system in copper-deficient rats using histopathology, immunohistochemistry, and scanning and transmission electron microscopy. Changes detected in the myocardium and interstitium were consistent with those reported for COD. Morphological changes included mesh-like changes in the capillary endothelial cells that appear to be a novel finding in COD-induced cardiomyopathy. These changes are hypothesized to result from abnormal vascular remodeling following damage to the basement membrane and due to the mechanical effects of myocardial contractions. Although cardiomyopathy may be associated with microcirculatory disorders arising from these lesions, further investigations are necessary to demonstrate a causal relationship between the pathogenesis of cardiomyopathy and the contribution of these lesions to disease progression. 相似文献
3.
Kiran Prasad Bhatta Akira Ishida Kenji Taniguchi Raksha Sharma 《Irrigation and Drainage Systems》2006,20(2-3):177-191
Management reforms are considered one of the best alternatives in increasing efficiency of the irrigation systems. Transfer of day-to-day operation and maintenance to farmers is not a new concept. However due to lags, even now it is a hot issue in developing countries and Nepal is not an exception. In this context of growing argument about the transfer of management of public irrigation systems to the Water Users' Group, this paper examines the comparative performance of farmer-managed and agency-managed irrigation systems. Khageri Irrigation System in the Chitwan district of Nepal was taken as the study site where complete management transfer has been done in 1996. The situations before and after complete transfer were compared. Intensive case studies of the selected farmers showed that equity in distribution of water and leakage had significantly improved after management transfer. Logit analysis revealed that age and education level of the household head, distance from main canal, leakage of the canal and equity in distribution are significantly related to the satisfaction level of the beneficiary farmers from FMIS compared to AMIS. However, landholding size of the respondent farmer has no significant effect. Similarly results from t-test revealed that rice productivity and overall profits from agriculture has also increased significantly due to irrigation management transfer. 相似文献
4.
Hiroshi UENO Osamu YAMATO Takeshi SUGIURA Moeko KOHYAMA Akira YABUKI Kenjiro MIYOSHI Kazuya MATSUDA Tsuyoshi UCHIDE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(1):91-95
A male Japanese domestic cat with retarded growth in Hokkaido, Japan, showed
progressive motor dysfunction, such as ataxia starting at 3 months of age and tremors,
visual disorder and seizure after 4 months of age. Finally, the cat died of neurological
deterioration at 9 months of age. Approximately half of the peripheral blood lymphocytes
had multiple abnormal vacuoles. Magnetic resonance imaging showed bisymmetrical
hyperintensity in the white matter of the parietal and occipital lobes in the forebrain on
T2-weighted and fluid-attenuated inversion recovery images, and mild encephalatrophy of
the olfactory bulbs and temporal lobes. The activity of lysosomal acid β-galactosidase in
leukocytes was negligible, resulting in the biochemical diagnosis of GM1 gangliosidosis.
Histologically, swollen neurons characterized by accumulation of pale, slightly granular
cytoplasmic materials were observed throughout the central nervous system. Dysmyelination
or demyelination and gemistocytic astrocytosis were observed in the white matter.
Ultrastructually, membranous cytoplasmic bodies were detected in the lysosomes of neurons.
However, genetic analysis did not identify the c.1448G>C mutation, which is the single
known mutation of feline GM1 gangliosidosis, suggesting that the cat was affected with a
new variant of the feline disease. 相似文献
5.
Itaru Shioya Koji Inoue Akihisa Abe Akira Takeshita Takahiro Yamaguchi 《Fisheries Science》2011,77(5):883-889
The meat quality of farmed yellowtail Seriola quinqueradiata fed on extruded pellets (EP) containing 0.5% (v/v) red pepper (experimental group) was compared with yellowtail of the same
age fed on EP (control group). In 1-year-old yellowtail, the crude lipid content of the dorsal muscle of the experimental
group tended to be lower than that of the control group. In contrast, there was no difference in the lipid content of the
dorsal muscle between the control group and the experimental group in 2-year-old yellowtail. The muscle texture of the experimental
group was significantly firmer than that of the control group, with the effect of red pepper unrelated to fish age and lipid
content. Color change of red muscle of the experimental group was significantly lower than that of the control group, and
the content of thiobarbituric acid-reactive substances in the red muscle was significantly lower in the experimental group
than in the control group. These results are the first to demonstrate that the inclusion of red pepper in the diet is able
to reduce the loss of muscle texture firmness and to slow down color change in red muscle of yellowtail. 相似文献
6.
Comparison of flower color with anthocyanin composition patterns in evergreen azalea 总被引:2,自引:0,他引:2
Daiki Mizuta Takuya Ban Ikuo Miyajima Akira Nakatsuka Nobuo Kobayashi 《Scientia Horticulturae》2009,122(4):594-602
In evergreen azaleas, major anthocyanins were detected from petals of wild species and cultivars by HPLC analysis. Depending on flower color, all samples were divided into three groups: red, purple or white, using the Japan color standard for horticultural plants. The chromatic components a* and b* values of red group samples showed a convergent distribution, whereas those of purple group samples showed a wider distribution. According to the HPLC analysis, red group samples had two to four major anthocyanins, and those of the purple group had two to six major ones. In contrast, no anthocyanins were detected in the white group petals, although anthocyanidins were detected. These results suggest that the anthocyanin constitution of the purple group flowers is more varied than that of the red group flowers, and this wider variety among purple flowers contributes to extending the diversity of flower color in evergreen azalea. 相似文献
7.
Hisayuki Arakawa Yohei Ohi Akira Matsumoto Kenji Takio Takumi Kimoto Katsutoshi Kawabe 《Fisheries Science》2012,78(5):1083-1090
The populations of red alga Gelidium elegans along the coast of Miyakejima Island were severely damaged by a volcanic eruption in 2000. The effect of this volcanic eruption has been long lasting, and populations of this red alga still have not recovered. We investigated the effect of seabed sediment particles derived from volcanic ash on the substrate adhesion of G.?elegans spores. The analysis provides evidence that increasing amounts of sediment particles result in lower adhesion rates of G.?elegans spores, and that smaller sediment particles have a greater influence on adhesion. The amount of seabed sediment particles around Miyakejima Island was 9.3?C1815.4?mg/cm2. This amount has changed greatly from year to year. The adhesion rate of G.?elegans spores in water around Miyakejima Island was 0?% at all points in 2008 and 2010, but it was estimated as 6.3?C38.6?% in 2009. These results suggest that there is significant inhibition of algal spore adhesion by seabed sediment particles derived from volcanic ash around Miyakejima Island. 相似文献
8.
Mitsuru Harada 《Soil Science and Plant Nutrition》2013,59(1):73-79
In most literature on soil, the term humus has been used as synonymous with soil organic matter, on the other hand, it has been applied to a portion of soil organic matter that has decomposed and has lost the structure of the original matter, from which it has derived. Scheffer and Schachtschabel 1) defined the humus not synonymously with soil organic matter, but, in a broad sense, as all the dead organic substances which are accumulated on the soil surface as well as in the soil layer, and undergo continually decomposition, alteration, and synthetic reactions. According to them, the composition groups of humus are divided into non-humic and humic, and the latter group is sub-divided into (1) fulvic acid and humo-lignin acid, (2) humic acid, (3) humin, and (4) humus coal. Some natures of these composition groups of humus are shown in Table 1. 相似文献
9.
Kinetic Parameters of Gross N Mineralization of Peat Soils as Related to the Composition of Soil Organic Matter 总被引:1,自引:0,他引:1
Bentio Heru Purwanto Akira Watanabe Jong Foh Shoon Ken-ichi Kakuda Ho Ando 《Soil Science and Plant Nutrition》2005,51(1):109-115
Peat land has been considered as an alternative type of land for agricultural development especially in the tropics. In the present study, the N-supplying capacity, one of the most important soil properties in terms of crop production, of peat soils was examined. Ten peat soil samples were collected from Indonesia, Malaysia, and Japan. Gross N mineralization in the soil samples was estimated using a zero-order model, and kinetic parameters of mineralization were determined using a simple type model. Soil organic matter composition was investigated using 13 C CPMAS NMR. Mineralization potential ( N 0 ), apparent activation energy ( E a ), and mineralization rate constant ( k ) ranged between 571–2,445 mg kg−1 , 281–8,181 J mol−1 , and 0.009–0.020 d−1 , respectively. Although none of the parameters showed a significant correlation with the soil C/N ratio, a negative correlation was observed between the k value and the ratio of the proportion of alkyl C in total C to that of O -alkyl C estimated by 13 C CPMAS NMR. The latter suggested that the k values were higher in the peat soils relatively rich in readily decomposable organic matter including carbohydrates. 相似文献
10.
Chemical characteristics and potential source of fulvic acids leached from the plow layer of paddy soil 总被引:2,自引:0,他引:2
To understand better the chemical characteristics and source of dissolved organic matter (DOM) leached from the plow layer of rice paddies, a lysimeter study was conducted, which simulated submerged paddy topsoil during rice growth. The fulvic acid (FA) fraction in the percolation water from the lysimeter was collected by adsorption onto insoluble polyvinylpyrrolidone (PVP), and the temporal variations in its elemental composition, molecular size distribution, IR spectra, 13C CPMAS NMR spectra, and δ13C values were investigated. The proportion of the FA fraction to bulk DOM varied greatly, but the chemical characteristics of the FA fraction did not change appreciably during the experimental period. Thus, it is considered that the changes in the DOM composition in percolation water were mainly due to the differing contributions of the FA fraction. Further, to investigate the source of the FA fraction in the leachate, the chemical characteristics of the FA fraction in the leachate were compared with those extracted from the plow layer soil. A sequential extraction of the FA fraction was conducted using a sequence of water, 0.25 M Na2SO4, 0.1 M Na4P2O7 (pH 7.0), 0.1 M Na4P2O7 (pH 10.5), and NaBH4+0.1 M Na4P2O7 (pH 10.5). It was found that the water- and 0.25 M Na2SO4-extractable fractions, which were most mobile, were not the only source of the FA fraction in the leachate. The small molecular size sub-fraction of the NaBH4+0.1 M Na4P2O7 (pH 10.5)-extractable FAs, most of which are probably bound mainly to iron oxides, are considered to be another source of the FA fraction leached from the plow layer of paddy fields. 相似文献