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91.
The efficiency of the indirect selection for wood density using the Pilodyn in Cryptomeria japonica was studied by comparing the Pilodyn penetration (PP) depth and the direct measurement of wood density in three test sites. The influence of the genotype by environment (G × E) interaction of wood density was estimated using the Pilodyn with common 12 C. japonica clones in 10 test sites in Kanto breeding region in Japan. The PP depth was highly correlated with wood density, and the genetic correlation between them was −0.88. The indirect selection using the Pilodyn realized 87% of the genetic gain obtained by the direct selection of wood density. The G × E interaction in PP depth was small. The ratio of the variance component of the G × E interaction to that of genotype was only 0.096 in the PP depth, whereas it was 0.700 in tree height and 1.410 in diameter at breast height. These findings indicate that the Pilodyn is useful for the genetic improvement of wood density in Cryptomeria japonica. The small G × E interaction in wood density estimated using the Pilodyn indicates that the relative clonal performance in wood density is stable among diverse environments in Kanto breeding region in Japan.  相似文献   
92.
The volcanic ashes derived from recent volcanoes are widely distributed in Japan from Hokkaido to Kyushu. Therefore the study on the weathering of these materials is very important from the pedological standpoint.  相似文献   
93.
The effects of chlordimeform on rectus abdominis muscle of frog were investigated. Chlordimeform (10?3M) caused a slow contraction, and at lower concentration (10?5–10?3M) it inhibited the acetylcholine-induced contraction in noncompetitive manner. When chlordimeform was applied to the muscle of Rana catesbiana, K+-induced contraction was also inhibited in noncompetitive manner. Whereas it had no effect on caffeine-induced contraction.Chlordimeform-induced contraction was not affected by respective addition of d-tubocurarine (10?4M), procaine (10?3M), or eserine (0.3 mM), which results were same as that of K+-induced contraction. Chlordimeform, at lower concentration (10?5–10?3M), inhibits the acetylcholine- and K+-induced contractions probably owing to depression of not only the sensitivity of endplate but also the excitability of cell membrane.  相似文献   
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Microorganisms from 45 jungle crows (Corvus macrorhynchos) captured from July to December 2002 at Ueno Zoo, Tokyo were identified as Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter cloacae, Enterobacter agglomerans, Pseudomonas maltophila, Staphylococcus spp., Micrococcus spp., and Streptococcus spp. E. coli showed the highest rate of isolation (21.6%). In an in vitro susceptibility test for 29 isolates of E. coli to 14 antimicrobial agents, all the isolates were resistant to penicillin G, vancomycin, erythromycin, lincomycin, bicozamycin, sulfadimethoxine, and olaquindox. Several isolates of them were also resistant to tetracycline, oxytetracycline, streptomycin, chloramphenicol, and ampicillin. Twenty-nine isolates were divided into 19 serogroups and the most frequently identified serogroups were O8, O114 and O144, which showed the same multidrug-resistant patterns.  相似文献   
96.
Animal by‐products can be recycled and used as sources of essential nutrients. Water‐soluble heme iron (WSHI), a functional food additive for supplementing iron, is produced by processing animal blood. In this study, we investigated the effects of dietary supplementation of 3% WSHI and exercise training for 4 weeks on the accumulation of abdominal fat and lipid metabolism in mice fed high‐fat diet. Exercise‐trained mice had significantly less perirenal adipose tissue, whereas WSHI‐fed mice tended to have less epididymal adipose tissue. In addition, total weight of abdominal adipose tissues was significantly decreased in the Exercise + WSHI group. Dietary WSHI significantly increased the messenger RNA (mRNA) levels of lipoprotein lipase and hormone‐sensitive lipase. WSHI‐fed mice also tended to show increased mRNA levels of adipose triglyceride lipase in their epididymal adipose tissue. Dietary WSHI also significantly decreased the mRNA levels of fatty acid oxidation‐related enzymes in the liver, but did not influence levels in the Gastrocnemius muscle. Exercise training did not influence the mRNA levels of lipid metabolism‐related enzymes in the epididymal adipose tissue, liver or the Gastrocnemius muscle. These findings suggest that the accumulation of abdominal fat can be efficiently decreased by the combination of dietary WSHI and exercise training in mice fed high‐fat diet.  相似文献   
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98.
转基因昆虫研究   总被引:6,自引:1,他引:5  
所谓转基因是指基因的转移 ,即用各种方法插入生物体自身不具有的基因 ,由于染色体遗传物质的交换而使其表现形态得以改变。通过转基因获得的生物称为转基因生物 ,即转基因植物与转基因动物。进而所谓转基因昆虫 ,是指在昆虫染色体上插入了别的生物的基因的重组昆虫。利用病毒导入外源遗传物质时 ,被重组的基因存在于病毒染色体上 ,于是病毒仅只感染生物体 (也称宿主 ) ,而不将重组基因传递给它的下一代。但是转基因昆虫则在染色体上进行了遗传物质的重组 ,一旦基因导入后 ,则可在后代中传递 ,与昆虫自身所具有的基因在后代中的表达完全相同…  相似文献   
99.
100.
Changes in subsets of peripheral blood mononuclear cells and lymphocyte blastogenesis reaction were observed after ozonated autohemoadministration (OAHA) in calves. Ten healthy calves were used in this study. After OAHA, CD8+ cells, CD14+ cells and WCl+cells increased (p<0.05). The level of lymphocyte blastogenesis stimulated by PHA decreased after OAHA. A significant increase in serum IL-6 activity was observed in OAHA calves. These results suggested that OAHA induced immunological changes in calves.  相似文献   
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