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61.
Grapevine yellow speckle viroid 1 (GYSVd 1) was first detected in Japan from commercial grapevines. The viroid seems to be spreading in Japanese commercial vineyards but without causing noticeable disease symptoms. Two Japanese GYSVd 1 isolates from the cultivars Campbell and Steuben were sequenced. The Campbell isolate is included in the type 2 variant of GYSVd 1, and the Steuben isolate is included in the type 3. Both of the isolates were grouped into the yellow speckle-inducing variants in the nucleotide sequence ; however, the etiological importance of this viroid on the viticulture of Japan has not yet been determined. Received 14 June 1999/ Accepted in revised form 25 August 1999  相似文献   
62.
A 2-year-old domestic shorthair cat was presented to us with decreased activity and anorexia. Hematologic findings revealed a mild non-regenerative anemia, thrombocytopenia, and leukocytosis with an increase in blast cells. Bone marrow aspirates also revealed a marked increase of blasts. The blastic cells were shown to be positive for peroxidase. Acute myeloblastic leukemia without maturation (M1) was diagnosed according to the FAB classification. Chemotherapy was initiated with cyclophosphamide, vincristine, prednisolone, and cytosine arabinoside. The cat responded partially. In total, the cats were given 7 blood transfusions. The cat died 14 weeks after first being presented to us.  相似文献   
63.
Body weight gain after weaning is correlated with villous height and disaccharidase activity. This evidence suggests that the maintenance of the small intestinal structure and function after weaning is important for the growth of piglets. We demonstrated that the influence of weaning age was obtained by disaccharidase activities and villous height in eight sections of the porcine small intestine. Therefore, we designed three weaning ages (weaned at the ages of 14, 21 or 28 days) and the piglets were slaughtered after 7 or 14 days post‐weaning. The remaining suckling piglets were slaughtered at the age of 1, 7, 14, 21 and 28 days. Four piglets were slaughtered at each event; therefore, 44 piglets were used in this study. Villous height and disaccharidase activities were measured in each section of the small intestine. Early weaning such as that at 14 days had severe influence on villous and disaccharidase activities. In particular, weaning of 14‐day‐olds did not result in maltase activity at least 2 weeks post‐weaning. Accordingly, the weaning age of crossbred piglets is recommended to be at least 21 days or more on the basis of villous height and disaccharidase activity analyses.  相似文献   
64.
Metabolism experiments with rats showed that significant isotope effects (kHkD = 2.4 to 3.5) were associated with the in vivo formation of dichloro and trichlorophenylmercapturic acids from a 1:1 mixture of normal and hexadeuterated lindane. This is evidence that rate-determining dehydrogenation and dehydrochlorination, both of which proceed with significant isotope effects, are essential in the pathway of dichloro- and trichlorophenylmercapturic acid formation from lindane. No significant primary isotope effects were associated (kHkD = 1.31 ± 0.17) with the formation of monochlorophenylmercapturic acid. This suggests that the 1,2-dechlorination to tetrachlorocyclohexene followed by glutathione conjugation is the probable pathway that produces this metabolite from lindane.  相似文献   
65.
Histiocytic sarcoma (HS) is a rare neoplasm of macrophages or dendritic cells with a poor prognosis in dogs. As the apoptosis inhibitor of macrophage (AIM) is characteristically expressed in canine macrophages, we hypothesised that AIM is involved in the development or progression of HS in dogs. In this study, AIM expression in the tumour region and serum AIM levels in dogs with HS was assessed. Additionally, the effects of AIM overexpression on HS cell viability were investigated using a HS cell line that was selected from five validated HS cell lines. Immunohistochemistry showed that AIM expression was observed in the cytoplasm of the HS cells. CD36, a candidate AIM receptor, was also observed on the cell membrane of HS cells. When the serum AIM level was detected in 36 dogs with HS and 10 healthy dogs via western blot analysis, the AIM levels in the HS dogs were significantly higher than those in the controls. AIM mRNA expression in the 5 HS cell lines varied but was higher than that in the other tumour-derived lines. Among the five HS cell lines, DH82 originally had lower AIM and the highest CD36 expression. When AIM was overexpressed in DH82, therein cell growth speed and invasion, apoptosis inhibition and phagocytic activity were strongly upregulated. These data suggest that elevated intra-tumour expression of AIM could induce the progression of HS cells in dogs. Moreover, elevated serum AIM levels in dogs with HS could serve as a biomarker of HS.  相似文献   
66.
利用振动法检测胶合板的抗弯弹性模量   总被引:6,自引:1,他引:6  
通过弯曲振动试验、纵波传播试验及纵波共振试验对胶合板的抗弯弹性模量进行无损检测,并分析了三种试验方法测定结果之间的关系。结果表明:虽然不同方法测得的胶合板弹性模量值不同,但其间存在一定的内在联系。  相似文献   
67.
在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。  相似文献   
68.
This study used a vibration test method to show that grain angles of face veneer have substantial effects on sound velocities and dynamic Youngs moduli of three types of wood-based composites. The sound velocity at 0° grain angle of face veneer was the highest, and it decreased with increasing grain angle in the range of 0° to 90°. This tendency was similar to that for dynamic Youngs modulus. The relationship between the grain angle of face veneer and the sound velocity of three types of wood-based composites can be expressed in the form of Hankinsons equation or a second-order parabolic equation. This study also showed that the application of orthotropic elasticity theory was valid for the three types of wood-based composites. The relationship between the grain angle of the face veneer and the Youngs modulus of three types of wood-based composites can be expressed in the form of the Jenkin equation, Hankinsons equation, or a second-order parabolic equation. Rule of mixture can also be used to predict the Youngs modulus of wood-based composite from the Youngs moduli of the two elements.Part of this study was presented at the 53rd Annual Meeting of the Japan Wood Research Society, Fukuoka, Japan, March 2003 and the 15th Annual Meeting of Chugoku Shikoku Branch of the Japan Wood Research Society, Higashi-Hiroshima, Japan, September 2003  相似文献   
69.
70.
The present work was undertaken from the standpoint of radical-capturing ability with regard to the antioxidative ability of flavonoids, especially flavonols distributed widely in woody plants. In regard to the flavonols, six methyl derivatives were initially prepared from quercetin and its litinoside. Their radical-capturing constants were determined strictly by the stopped-flow spectroscopic method. It was proved that the radical-capturing ability of quercetin mainly involves the vicinal C3. and C4, hydroxyl groups and the C3 hydroxyl group. To clarify the reaction mechanism begun at the C3 hydroxyl group of quercetin, 5,7,3,4-tetramethylquercetin (TMQ), flavon-3-ol (F30) and so on were treated with 2,2-azo-bis-(2,4-dimethylvaleronitrile) (AMVN). Six products (1–6) containing one depside and its two hydrolytic products, two valeronitrile adducts, and others were isolated from the reaction mixture of TMQ and their structures determined by instrumental analyses. Similarly, F30 gave four products, 7–10, which corresponded to the above products 1–3 and 5 (one depside, its two hydrolytic products, and one adduct), respectively. 3,5,7,3,4-Pentamethylquercetin (PMQ) and flavon-3-O-methylate (F3M) gave no products. The quantitative change of the products with reaction time was determined spectroscopically. An initial reaction pathway for the radical-capturing reaction of flavon-3-ols with AMVN was proposed based on the products and their amounts. The main route — formation of depside and its hydrolytic products via ketohydroperoxide (3) or ketohydroperoxy radical (4) - was similar to that of the oxidation reaction of quercetin with quercetinase and light.Part of this paper was presented at the 46th and 47th annual meetings of the Japan Wood Research Society, Kumamoto and Kouchi, April 1996 and 1997  相似文献   
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