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1.
花器发育调节基因gaga1转化大豆的初步研究   总被引:1,自引:0,他引:1  
通过花粉管通道法用非洲菊基因gaga1转化N2899(质核互作雄性不育保持系)、通州豆、95—7等大豆受体。处理的花朵总数为4300朵,共获3000多粒种子。经卡那霉素田间鉴定,获得了14株抗卡那霉素的幼苗。通过抗性标记基因nptⅡ和目标基因gaga1的PCR检测,发现有两株N2899具有阳性信号,初步证明非洲菊基因gaga1已整合到这两株大豆的基因组中。形态分析表明:与未转化N2899相比,转基因大豆株型矮小,始花期提前,盛花期花数量较少,结荚不多。显微分析发现,与对照相比转基因大豆花器官结构没有明显改变。  相似文献   
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Sulfa antibiotics (sulfonamides) are a group of molecules sharing the p-aminobenzenesulfonamide moiety. Sulfonamides are used in veterinary and human medicine. Sometimes, the meat or milk of medicated animals is contaminated with residual sulfonamides. Current analytical methods for sulfonamides are unfit for screening of food, because they are either too laborious, insensitive, or specific for a few sulfa compounds only. A rapid immunoassay for detection of all sulfas in a single reaction would thus be useful. Previously, we used protein engineering to improve the broad specificity of sulfa antibody 27G3. In this study, we improved the best mutant of the previous studies with site-directed mutagenesis. The new mutants recognized different sulfonamides with affinities sufficient for detection of all 13 tested sulfonamides below the MRL level. We furthermore demonstrated the functionality of one mutant in some real sample matrices.  相似文献   
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Improving broad specificity hapten recognition with protein engineering   总被引:1,自引:0,他引:1  
Sulfa antibiotics (sulfonamides) are derivatives of p-aminobenzenesulfonamide that are widely used in veterinary medicine. Foods derived from treated animals may be contaminated with these drugs. However, current immunobased sulfonamide detection methods are unfit for screening of products because they are either too insensitive or specific for a few compounds only. An immunoassay capable of detecting all sulfas in a single reaction would be ideal for screening. For development of a binder capable of binding all sulfas, a protein engineering approach was chosen and the properties of monoclonal antibody 27G3 were improved with mutagenesis followed by selection with phage display. Several different mutant antibodies were isolated. The cross-reaction profile of the best mutant antibody was significantly improved over that of the wild-type antibody: it was capable of binding 9 of the tested 13 sulfonamides within a narrow concentration range and also bound the rest of the sulfas, albeit within a wider concentration range.  相似文献   
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Interspecific somatic hybrids produced by protoplast fusion between two wild Solanum species (S. acaule, acl; S. brevidens, brd) and cultivated potato Solanum tuberosum (tbr) were analyzed in terms of the starch nanometer-range structure and glycoalkaloid (GA) contents. The crystallinity of starch granules, the average size of starch crystallites, and the lamellar distances were obtained from tuber samples using wide-angle and small-angle X-ray scattering methods. These measurements showed that incorporation of wild genomes from either nontuberous (brd) or tuberous (acl) Solanum species caused no significant modifications of the nanostructure of potato starch. In contrast, the GA profiles of the hybrids, which were analyzed by LC-ESI-MS in both tuber and foliage samples, differed considerably from those of cultivated potato. Regardless of the low total tuber GA concentrations (approximately 9 mg/100 g of fresh weight), the somatic hybrids contained GAs not detected in the parental species. A high proportion of spirotype GAs consisting of 5,6-dihydrogenated aglycons, for example, alpha-tomatine and tomatidine bound with solatriose, and chacotriose were found in the hybrids. In conclusion, the foliage of interspecific hybrids contained a higher variation in the structures of GAs than did the tubers.  相似文献   
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The deer ked (Lipoptena cervi) is a haematophagous parasitic fly of cervids that spread to Finland in the early 1960's. Presently its northern distribution limit lies at approximately 65°N and it is gradually spreading northwards. In Finland the principal host species has been the moose (Alces alces), but the deer ked is about to establish contact with another potential host, the semi-domesticated reindeer (Rangifer tarandus tarandus) causing possible threats to reindeer health and management. The aim of this study was to investigate if the deer ked would have an influence on the welfare of the reindeer. Eighteen adult reindeer were divided into three experimental groups: the control group and two infected groups with 300 deer keds per reindeer introduced in August-September. One of the infected groups was treated with subcutaneous ivermectin in November. To gather comprehensive data on potential health hazards caused by the deer ked a wide array of physiological variables was measured during and at the end of the experiment in December. The keds caused no clear changes in the complete blood count, plasma clinical chemistry, amino acids, endocrinology, energy stores, enzyme activities or tissue fatty acid profiles of the host. The haematological, clinical chemical and endocrinological values displayed changes that could be related to the seasonal physiological adaptations of the species. In conclusion, at the duration and intensity of infection that were employed, the effects of the deer ked on the measured physiological variables of the reindeer were insignificant.  相似文献   
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A new terrestrial laser system was tested for tree species classification. A dataset consisting of shape parameters of three boreal tree species was collected with Light Detection and Ranging (LIDAR) and integrated with an actively measured reflectance hyperspectra. Tree species were classified using parameters derived from reflectance spectra and point cloud shape distribution. Classification performance was tested with individual, paired, and mixed combinations of both reflectance and shape parameters. The best classification results were obtained with combined datasets consisting of two reflectance and two shape parameters. Of all tested classification parameter combinations, 67.5% were able to classify all trees with over 90% accuracy. The best reflectance spectrum bands for the examined species were located around 550 and 700 nm. The best shape parameters described the upper midsection or the tops of the trees. This study was a successful step in developing classification algorithms for integrated LIDAR and hyperspectral data.  相似文献   
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Major revisions of the Finnish Forest Act were carried out in 1994–1996 and 2010–2013. The need for revision emerged from societal changes and changes in the forest sector’s operational environment that related to the globalisation of markets and influences of international policies. This study analysed the influences of global and European Union forest and environmental policies on the revision of the Forest Act by combining advocacy coalition framework with the four pathways of influence framework introduced by Bernstein and Cashore. The results show that the three identified advocacy coalitions, namely Forestry administration, Private forestry and Environmental coalition remained rather stable over the two revision processes from 1990s to 2010s. The importance of the different pathways of international influence differed between the coalitions. Private forestry and Forestry administration coalitions, which represented forestry paradigm, stressed market-related arguments, whereas Environmental coalition representing environmental paradigm mainly referred to international legally binding rules and non-legally binding initiatives. The argumentation of the actors indicated that international rules and international norms and discourse were regarded to be as equally important.  相似文献   
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