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鸡马立克氏病二价活疫苗免疫协同作用研究@吴长新@刘秀梵@吴艳涛@张如宽@甘军纪@刘慧谋@彭大新@李胜$江苏农学院动物医学系@李胜$杭州市近江种鸡场鸡;马立克氏病;二价+疫苗;免疫协同作用农业部“七·五”重大攻关项目;江苏省“八·五”重大攻关项目...  相似文献   
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For examining the probability of increase in the occupation ratio of inoculated rhizobium in nodules, various Rj-soybean cultivars including the Rj 2 Rj 3 Rj 4-lines of soybean were grown in a field of the Kyushu University Farm. Bradyrhizobium japonicum USDA110 that carries uptake hydrogenase (Hup+) was used as an inoculum. The relative efficiency of nitrogen fixation generally increased by the inoculation. However, there were no significant differences in the effects among the genotypes of the host plants. The occupation ratio of serogroup USDA110 in the nodules on the taproot of the inoculated plants was in the range of 77–100%, suggesting that the B. japonicum strain USDA110 infected taproots immediately after inoculation. The occupation ratios in the nodules on the lateral roots were 53–67, 40–86, 63–83, and 62–77% in inoculated plants of the non-Rj-, Rj 2 Rj 3-, Rj 4-, and Rj 2 Rj 3 Rj 4-genotypes, respectively, and they decreased in all the genotypes with the progression of growth. At the time of the first sampling, the occupation ratios on the lateral roots of these Rj 2 Rj 3 Rj 4-genotypes showed values intermediate between those of IAC-2 (Rj 2 Rj 3) and Hill (Rj 4) , which were the parent cultivars of the Rj 2 Rj 3 Rj 4-lines, B340, B349, and C242. The reduction in the occupation ratio of the serogroup USDA110 for about 1 month after the first sampling was the lowest (0.13–0.16) in the Rj 2 Rj 3 Rj 4-genotypes, excluding B349, followed by the non-Rj- and Rj 2 Rj 3-genotypes and highest (0.52–0.69) in the Rj 4-genotypes, excluding Hill. Therefore, it was considered that the population of compatible rhizobia with host soybean plants increased in the rhizosphere with the progression of the development and growth. The results showed that with the expansion of the root area of host plants, the occupation ratio of type A rhizobia including the serogroup USDA110 was high. Therefore, the Rj 2 Rj 3 Rj 4-genotypes were superior to other Rj-genotypes in terms of the inoculation effects of nodulation type A rhizobium, B. japonicum USDA110. However, the preference of the Rj 2 Rj 3 Rj 4-genotype for serogroup USDA110 is not sufficient to rule out the competition with the other serogroups in this study. Therefore, the study should be centered on the isolation of more efficient (Hup+) and highly compatible rhizobial strains with the Rj 2 Rj 3 Rj 4- genotypes.  相似文献   
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We isolated 629 fungi from 1296 berry seeds of solanaceous plants, including tomato (Lycopersicon esculentum), eggplant (Solanum melongena), bell pepper (Capsicum annuum), and red pepper (Capsicum annuum var. annuum) preserved for long and short terms. The isolates were classified into 22 genera excluding unidentified fungi, and the fungal floras were divided into two types: the tomato–eggplant and pepper groups. The results of cluster analysis with unweighted pair-group method with arithmetic average also supported these groups. Most tomato seeds infested with Geotrichum candidum germinated and grew the same as uninfested seeds. Cladosporium sphaerospermum and Arthrinium sp. isolated from eggplant seeds strongly suppressed germination, and Penicillium variabile suppressed seminal root elongation on eggplant. Alternaria alternata, Botrytis cinerea, and Myrothecium verrucaria detected from red pepper or bell pepper seeds were pathogenic to the fruits and the seedlings after artificial inoculation.  相似文献   
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The effects of lipids, emulsifiers, and ethanol on the absorption of orally administered quercetin in rats were investigated for its efficient intestinal absorption. Rats were administered 150 micromol/kg quercetin in water supplemented with lipids and/or emulsifiers, or ethanol, and blood was collected from the tail for 6 h after administration. Co-administration of lipids such as lecithin and soybean oil or emulsifiers including sucrose fatty acid ester, polyglycerol fatty acid ester, and sodium taurocholate had no statistically significant effects on quercetin absorption, although these constituents rather increased the accumulation of conjugated forms of quercetin and those of isorhamnetin in rat plasma. However, the combination of lipids and emulsifiers enhanced the absorption of quercetin significantly. Thirty and fifty percent (v/v) of the ethanol in the vehicle raised the efficiency of quercetin absorption in a concentration-dependent manner. Quercetin absorption-enhancing effects of these constituents seemed to be affected by quercetin's solubility in respective vehicles used for the administration. Ethanol is not helpful for the effective absorption of quercetin, as a high concentration is required. In conclusion, a combination of lipids and emulsifiers is necessary for enhancing quercetin absorption.  相似文献   
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Within-stem variations in the mechanical properties of 17–19-year-old Melia azedarach planted in two sites in northern Vietnam were examined by destructive and nondestructive methods. Wood samples were collected from 10, 50, and 90% of the radial length from pith on both sides (North and South) at 0.3, 1.3, 3.3, 5.3, and 7.3 m heights above the ground. The mean values in whole trees of wood density (WD), modulus of rupture (MOR), modulus of elasticity (MOE), and dynamic modulus of elasticity (Ed) at 12% moisture content were 0.51 g/cm3, 78.58 MPa, 9.26 GPa, and 10.93 GPa, respectively. Within the stem, the radial position was a highly (p?<?0.001) significant source of variation in mechanical properties. MOR, MOE, and Ed increased from pith to bark. WD had a strong positive linear relationship with both MOR (r?=?0.85, p?<?0.001) and MOE (r?=?0.73, p?<?0.001). This suggests that it is potentially possible to improve mechanical properties through controlling WD. MOR had also a strong linear relationship with Ed (r?=?0.84, p?<?0.001). This indicates that Ed is a good indicator to predicting the strength of wood if the density of measured element is known. Besides, the stress wave method used in this study provides relatively accurate information for determining the stiffness of Melia azedarach planted in northern Vietnam.  相似文献   
7.
The pedigrees of 3 Dalmatian dogs afflicted with copper-associated hepatitis were investigated to discover the mode of inheritance. A composite family pedigree showed that the 3 affected Dalmatians were related. None of the parents of the affected dogs showed clinical symptoms of liver disease, and the disease had no sex predisposition. The estimated segregation ratio was approximately 3:1 based on surviving littermates. These findings suggested that the copper-associated hepatitis in these Dalmatians was an autosomal recessive mode of inheritance. In addition, some male Dalmatians imported from abroad might have been involved in the occurrence of this disease in Japan.  相似文献   
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指出了地表温度作为地表能量平衡中的异常重要的参数之一,它在地表与大气相互作用过程当中发挥着非常重要的作用,在地表能量平衡的研究也扮演着重要角色,特别在气象、水文、地质、生态等众多领域有着非常广泛的应用需要。对现有的地表温度反演的4种算法进行比较,最终确定选择劈窗算法。根据劈窗算法的需要,对 M ODIS数据波段选取,反演出黄河三角洲地区地表温度,并且利用实测的地表温度进行反演结果精度分析。  相似文献   
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采用水蒸气蒸馏法从柠檬叶中提取挥发油中的油相成分,进一步以乙醚为溶剂从蒸馏馏出液中萃取挥发油中的水溶性物质;利用气相色谱-质谱联用(GC-MS)表征了二者的化学成分,根据气相色谱峰面积归一化法进行定量.通过表征和分析比较得到:柠檬叶挥发油油相成分得率为0.33%(以鲜叶计),确定了其中的30种成分,占油相成分总量的96.35%,其主要成分为d-柠檬烯(29.91%),其后依次为β-蒎烯(20.37%)、香茅醛(18.52%)、桧烯(5.74%).柠檬叶水溶性成分得率为0.03%(以鲜叶计),确定了其中的30种成分,占水相成分总量的97.94%,其主要成分为d-柠檬烯(30.33%)、香茅醛(21.88%)、β-蒎烯(19.83%)、桧烯(6.49%).  相似文献   
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