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大豆Kunitz型胰蛋白抑制剂现已报告有6个电泳形态,Tia,Tib,Tic,Tia-s,Tib-f一一个最慢的电泳移动形态。Tia,Tib,Tic的活性已被报道。Tia和Tic有相似的活性,Tib的活性低于前两者。本文使用DEAE-cellulose层析化纯化了Tia和Tia-s蛋白和测定比较了这两个形态的活性。  相似文献   
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While rights-based management systems have often been encouraged as effective management tools, few studies have analyzed the effects of those systems empirically. In this article, we have focused on a special form of the territorial use rights in fisheries strategy, namely, an income-pooling system, and examined the effects of this system empirically. Earlier studies have regarded the control of fish landing amount and improvement of the quality of fish as the two main determining factors in such a system. Consequently, in our study, we estimated the relationships between these two factors and the price of fish using the econometric method. The results show that the two factors do indeed have significant effects on price changes.  相似文献   
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Chum salmon Oncorhynchus keta eggs from the Chitose and Shiriuchi rivers in Hokkaido, northern Japan, were incubated under identical conditions with the aim of comparing vertebral number (V N) to that reported archived data from the 1950s. The comparison revealed that mean V N of salmon from the Shiriuchi River has remained unchanged for 50 years and is higher than that from the Chitose River. The V N in the Chitose River salmon was found to be significantly higher than that recorded in the archival data. The variation in the mean V N of chum salmon fry collected during different seasons and years in the Chitose River falls within a range that has remained constant, suggesting that the difference between the values obtained in our study and the archival data may be due to differences in the timing of egg collection. These results indicate that the mean V N of chum salmon has been stable for a long period. Incubation experiments under identical conditions are a useful tool for examining changes in genetic structure and detecting the essential properties of populations.  相似文献   
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不同基因型对白菜子叶培养不定芽再生的影响   总被引:7,自引:0,他引:7  
探讨了基因型对白菜子叶培养不定芽再生的影响。结果表明,不同基因型的不定芽再生率和平均每子叶生芽数差异极大,在被检索的123个大白菜和20个小白菜品种中,芽再生率为0-97.5%,平均每子味生芽数为1.0-10.7个。17个大白菜和5个小白菜品种的不定芽再生率在80%以上。芽再生率与品种起源地、结球类型及熟性无相关。  相似文献   
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This study was conducted to evaluate immunological changes in peripheral blood leukocytes in pigs that were genetically selected for their improved resistance to mycoplasmal pneumonia of swine (MPS), using MPS vaccine as an antigen. Twelve castrated MPS‐selected Landrace pigs were compared with the same number of pigs from a nonselected line by using a time‐course analysis at the hematological level. After the second sensitization with MPS vaccine, the percentages of B cells, CD4+ T cells, and natural killer (NK) cells in total leukocytes were lower in the selected line than in the nonselected line, whereas the percentage of granulocytes in total leukocytes increased in the MPS‐selected line. We also assessed the proliferative ability of peripheral blood mononuclear cells (PBMCs) stimulated with Mycoplasma hyopneumoniae, lipopolysaccharide or concanavalin A, and found that although the proliferative ability of the PBMC was not different between the two lines at a steady state, the nonselected line showed a significantly higher proliferative ability after sensitization with MPS vaccine than the selected line regardless of antigens used. These results thus indicate that the selection of pigs on the basis of MPS resistance changes their immunophenotype, and would give us beneficial information for the prevention of MPS infection.  相似文献   
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Nitrogen uptake and nitrate-N concentration in forage sorghums, which are related to ground water pollution or feed quality under conditions of crop fertilization by only animal wastes, were examined. Seventy-four genotypes of sorghum and Sudan grass were tested. They were classified into 4 groups; grain type and dual purpose type sorghums (6 and 13 genotypes, respectively, Sorghum bicolor Moench), sorgo type sorghum (21, S. bicolor), Sudan type sorghum (22, S. bicolor × S. sudanense (Piper) Stapf), Sudan grass (12, S. sudanense). There was a strong correlation between dry matter (DM) yield and N uptake, with the sorgo type producing the highest DM matter yield and showing the highest N uptake. Nitrate-N, which causes nitrate poisoning of ruminants, was detected mostly in the stem of all the genotypes. The nitrate-N concentration based on DM could be calculated accurately by multiplying the nitrate-N concentration of stem on a fresh matter basis by the DM partitioning ratio of stem divided by the DM concentration of stem. The grain type and the dual purpose type of sorghums with dry stem showed the lowest nitrate-N concentration because these plants had a lower DM partitioning ratio of stem and higher DM concentration of stem. Sudan grass and Sudan type sorghum with the genetic background of Sudan grass showed higher nitrate-N concentrations owing to their ability to accumulate nitrate-N.  相似文献   
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The aim was to characterize the changes of plasma component concentrations after feeding in Japanese Black (B) and Japanese Shorthorn (S) cattle. Eight females, five B and three S, with a mean bodyweight (standard deviation) of 282.0 (20.3) kg were selected and supplied with only water for 28 h after feeding. Blood was taken from the jugular vein at 4‐h intervals for 32 h after feeding. Metabolite (cholesterol, CL; glucose, GLU; nonesterified fatty acid, NEFA; triacylglycerol, TG; total protein, TP) and insulin‐like growth factor‐1 (IGF‐1) concentrations in plasma were measured. In both breeds GLU tended to decrease linearly with a similar slope. Differences between the initial mean NEFA at 4 h after feeding (Start) and that at 24 h after the start (End) were significant in both breeds, but S increased significantly more than B at and after 8 h from the Start. The TG in S tended to change more than in B, and CL and IGF‐1 in both breeds changed continuously at similar levels. The TP in B tended to decrease more slowly and be lower than S. The change in NEFA, especially, suggests that nutritional status sensitively reflects genetic background.  相似文献   
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