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971.
ABSTRACT:   Hepatopancreases were washed four times with 2% acetic acid solution. In both the washed hepatopancreases and the supernatant of the washing solution, the residual cadmium (Cd) concentration was in accordance with the required standard for organic fertilizers. Hepatopancreases do not naturally contain high levels of nitrogen, but they do contain several amino acids which are useful for cultivation, and these were retained during the washing process. Although the condensed precipitate of the washing solution contained a considerable amount of Cd, Cd elution levels at the time of final disposal met judgment standard for special management industrial waste as a result of kneading and immobilizing with chelating adsorbent for treatment of contaminated soil. The volume of the precipitate of the washing solution was one-fifth of the original hepatopancreas, and the solid waste was suitable for burial at a final disposal site without further treatment.  相似文献   
972.
ABSTRACT:   Tyrosinase inhibitor-producing fungus of Trichoderma sp. strain H1-7, which was isolated from marine sediment, was investigated by phylogenetic analysis and physiological characteristics. Phylogenetic analyses of the strain were similar to Trichoderma atroviride or T. viride . Physiological characteristics of the strain were similar to T. viride , and based on these results, it was identified as T. viride . Characterization of tyrosinase inhibitory activity of a culture supernatant of the strain was investigated. The inhibitory activity of the supernatant of the strain decreased after cultivation for more than 3 days. Furthermore, sea water was not essential for the production of the tyrosinase inhibitor (TI). When TI production of the strain was compared to T. viride , the strain showed higher activity than T. viride . From this result, it seemed that the strain had characteristic features comparable to T. viride , which was isolated from the terrestrial environment. As TI production of the strain showed higher potential than that of T. viride , it is necessary to elucidate the chemical structure of TI exemplified in the present study.  相似文献   
973.
Degenerative cranial cruciate ligament (CCL) rupture is characterized histologically by degenerating extracellular matrix (ECM) and chondroid metaplasia. Here, we describe the progression of chondroid metaplasia and the changes in the expression of ECM components in canine CCL rupture (CCLR). CCLs from 26 stifle joints with CCLR (CCLR group) and normal CCLs from 12 young beagles (control group) were examined histologically and immunohistochemically for expression of type I (COLI), type II (COLII), type III collagen (COLIII) and Sry-type HMG box 9 (SOX9). Cell density and morphology of CCLs were quantified using hematoxylin–eosin staining. The percentage of round cells was higher in the CCLR group than in controls. COLI-positive areas were seen extensively in the connecting fibers, but weakly represented in the cytoplasm of normal CCLs. In the CCLR group, there were fewer COLI-positive areas, but many COLI-positive cells. The percentages of COLII-, COLIII- and SOX9-positive cells were higher in the CCLR group than in controls. The number of spindle cells with perinuclear halo was high in the CCLR group, and most of these cells were SOX9-positive. Deposition of COLI, the main ECM component of ligaments, decreased with increased COLIII expression in degenerated CCL tissue, which shows that the deposition of the ECM is changed in CCLR. On the contrary, expression of SOX9 increased, which may contribute to the synthesis of cartilage matrix. The expression of COLII and SOX9 in ligamentocytes showed that these cells tend to differentiate into chondrocytes.  相似文献   
974.
We previously investigated rabbit hereditary cerebellar cortical degenerative disease, called cerebellar cortical abiotrophy in the veterinary field, and determined that the pathogenesis of this disease is the result of failed synaptogenesis between parallel fibers and Purkinje cells. In this study, longitudinal changes in the development and atrophy of the cerebellum of rabbits with hereditary abiotrophy after birth were morphometrically examined (postnatal day [PD] 15 and 42) using image analysis. Although development of the cerebellum in rabbits with abiotrophy was observed from PD 15 to PD 42, the growth rate of the cerebellum was less than that in normal rabbits. In rabbits with abiotrophy, the number of granular cells undergoing apoptosis was significantly higher at PD 15 and dramatically decreased at PD 42. The number of granular cells did not increase from PD 15 to 42. The synaptogenesis peak at PD 15 occurred when the largest number of apoptotic granular cells in rabbits with abiotrophy was observed. Although 26% to 36% of parallel fiber terminals formed synaptic junctions with Purkinje cell spines, the remainder did not at PD 15 and 42. The rate of failure of synaptogenesis in the present study might be specific to this case of abiotrophy. Morphometric analysis revealed detailed changes in development and atrophy in animals with postnatal cerebellar disease occurring soon after birth.  相似文献   
975.
The structure and functions of placentas were examined in 3 species of rorqual whales, common minke (Balaenoptera acutorostrata), Bryde’s (B. brydei) and sei (B. borealis) whales, with the aim of confirming the structural characteristics of the chorion, including the presence of the areolar part, and clarifying steroidogenic activities and fetomaternal interactions in the placentas of these whales. Placentas were collected from the second phase of the Japanese Whale Research Program under Special Permit in the North Pacific (JARPN II). Histological and ultrastructural examinations revealed that these whale placentas were epitheliochorial placentas with the interdigitation of chorionic villi lined by monolayer uninucleate cells (trophoblast cells) and endometrial crypts as well as folded placentation by fold-like chorionic villi. Moreover, well-developed pouch-like areolae were observed in the placentas, and active absorption was suggested in the chorionic epithelial cells of the areolar part (areolar trophoblast cells). Berlin blue staining showed the presence of ferric ions (Fe3+) in the uterine glandular epithelial cells and within the stroma of chorionic villi in the areolar part. An immunohistochemical examination revealed tartrate-resistant acid phosphatase (TRAP; known as uteroferrin in uteri) in the cytoplasm of glandular cells and areolar trophoblast cells. This result suggested that, in cetaceans, uteroferrin is used to supply iron to the fetus. Furthermore, immunoreactivity for P450scc and P450arom was detected in trophoblast cells, but not in areolar trophoblast cells, suggesting that trophoblast cells synthesize estrogen in whale placentas. Therefore, we herein immunohistochemically revealed the localization of aromatase and uteroferrin in cetacean placentas during pregnancy for the first time.  相似文献   
976.
The thoracic vertebral number is associated with body length and carcass traits, and represents one of the most important traits in the pig industry. Recent studies have shown that vertnin (VRTN) gene is associated with variations in the vertebral number in commercial European pigs. However, the genetic relationships and effect of this VRTN gene in pig production and carcass traits remain uncertain. Therefore, we investigated the genetic relationships among traits such as vertebral numbers, carcass weight and length‐related traits, and meat production traits, and the effect of VRTN gene polymorphisms on these traits in a Duroc purebred population selected for its meat production traits. Highly positive genetic correlations were obtained between the thoracic vertebral numbers and length‐related traits (0.56 to 0.84), whereas low correlations were obtained with production traits and carcass weight (?0.16 to 0.05). VRTN gene polymorphisms indicated that the number of thoracic vertebrae and length‐related traits were significantly associated with the VRTN genotype, but had no significant effect on production traits and carcass weight. The results indicate that VRTN gene may be used as an effective selection marker to obtain pigs with high thoracic vertebral numbers and length‐related traits, without adversely affecting meat production traits.  相似文献   
977.
日本柳杉高频真空干燥及防止开裂的研究   总被引:1,自引:0,他引:1  
通过对日本人工林木材柳杉髓心方材进行系列高频真空干燥试验 ,掌握柳杉髓心方材的干燥特性及相应的高频真空干燥条件。结果表明 :高频真空干燥前在常压下进行合理的蒸汽和过热蒸汽预处理 ,柳杉髓心方材可有效地提高干燥质量 ,尤其可防止开裂产生  相似文献   
978.
人工林杨木的高频真空干燥工艺   总被引:1,自引:0,他引:1  
在人工林杨木的高频真空干燥系列试验中,通过不断改变干燥工艺参数并分析总结试验结果,从而确定杨木高频真空干燥适宜的工艺基准。结果表明,在本试验确定的高频真空干燥工艺下,初含水率较高的杨木不仅能保证干燥质量,而且干燥速度可比常规蒸汽干燥法和高温蒸汽干燥法提高数倍。  相似文献   
979.
We used a two-dimensional finite element method to analyze the load-slip characteristics of nailed wooden joints sheathed with a panel. We used tests of nail bending, nail shank embedment in a wood or a panel, nail-head embedment in a face of a panel, nail withdrawing from a wood, friction between a wood and a panel, and initial axial forces of the nails. The values of the material properties for the analytical models were determined with the above tests. With a conventional one-dimensional analysis it is impossible to evaluate the shearing performance accurately because the axial forces of the nail are not calculated. Therefore, we used two-dimensional geometric nonlinear analysis. The computed load-slip curves closely matched the original experimental results; and when the friction and initial axial forces were considered, the computed curves were more likely to match the original experimental results. Our results suggested that it is better to use geometric nonlinear analysis to analyze the shearing characteristics of nailed joints, and that friction and axial forces are important factors for accurate analysis.Parts of this report were presented at the 7th World Conference on Timber Engineering, Malaysia, August 2002  相似文献   
980.
Within-tree variations of derived wood properties of Runkel ratio, Luces shape factor, slenderness ratio, and solids factor were examined for Eucalyptus camaldulensis and Eucalyptus globulus trees and the tendency difference in the within-tree variations between individuals and between species, in both radial and axial directions by statistical data analysis. These properties are important for quality breeding of pulpwood. In both species, within-tree variations were generally observed as higher values in the upper and outer parts compared with other parts of the trunk for Runkel ratio and Luces shape factor. In E. camaldulensis, within-tree variations were observed as higher values in the upper and outer parts compared with other parts of the trunk for slenderness ratio and solids factor. In E. globulus, within-tree variations were observed as higher values in the outer parts compared with other parts for slenderness ratio and solids factor. However, significant difference of tendency was observed in radial variation between individuals of E. globulus for Runkel ratio and in both radial and axial variations between species for solids factor. Furthermore, within-tree variations of derived wood properties were analyzed to determine a sampling height in the trunk which can be used to represent whole-tree values. Representative heights of derived wood properties from two trees were found to be 2.8m in E. camaldulensis (except for Runkel ratio and Luces shape factor) and 1.8m in E. globules (except for Runkel ratio), regardless of differences in tree height (growth rate) and in tendency of within-tree variation of derived wood properties.  相似文献   
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