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1.
The next generation of biotechnology-derived products with the combined benefit of herbicide tolerance and insect protection (MON 88017) was developed to withstand feeding damage caused by the coleopteran pest corn rootworm and over-the-top applications of glyphosate, the active ingredient in Roundup herbicides. As a part of a larger safety and characterization assessment, MON 88017 was grown under field conditions at geographically diverse locations within the United States and Argentina during the 2002 and 2003-2004 field seasons, respectively, along with a near-isogenic control and other conventional corn hybrids for compositional assessment. Field trials were conducted using a randomized complete block design with three replication blocks at each site. Corn forage samples were harvested at the late dough/early dent stage, ground, and analyzed for the concentration of proximate constituents, fibers, and minerals. Samples of mature grain were harvested, ground, and analyzed for the concentration of proximate constituents, fiber, minerals, amino acids, fatty acids, vitamins, antinutrients, and secondary metabolites. The results showed that the forage and grain from MON 88017 are compositionally equivalent to forage and grain from control and conventional corn hybrids.  相似文献   
2.
The plasma membranes of hamster, mouse, and human tumor cell lines that display multiple resistance to drugs were examined by gel electrophoresis and immunoblotting. In every case, increased expression of a 170,000-dalton surface antigen was found to be correlated with multidrug resistance. This membrane component is of identical molecular size and shares some immunogenic homology with the previously characterized P-glycoprotein of colchicine-resistant Chinese hamster ovary cells. This finding may have application to cancer therapy.  相似文献   
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We investigated the morphology and germination of Tamarindus indica seeds in order to discover the effects of variation in seed sources and pre-sowing treatments on germination. The experiment was carried out in the nursery of the Forestry and Wood Technology Discipline, Khulna University, Bangladesh. Seeds were collected from different but healthy trees from various locations in Bangladesh and subjected to four pre-sowing treatments, i.e., control, immersion in cold water (4°C for 24 h), immersion in hot water (80°C for 10 min) and scarification with sand paper. Seed germination was carried out in poly-bags with a mixture of topsoil and cow dung in the ratio of 3:1. The average length of the fresh seeds was 1.35±0.26 cm, their width 1.07 ±0.20 cm and thickness 0.69±0.11 cm. The results revealed that pre-sowing treatments affected the germination process of seeds, which significantly increased the germination percentage with the cold water (81.67%) and scarification with sand paper (82.33%) treatments, compared with those in the control (58.33%) and hot water treatment (59.00%). In all treatments germination started on average within 5 to 7 days after the start of the treatments and were completed from 13 to 19 days later. The greatest success in germination (82.33%) was found in scarification with sand paper, followed with 81.67% in the cold water treatment. The results of analyses of variance (ANOVA) showed significant differences (p<0.05) in germination closing dates, seed germination periods and germination percentages among the treatments but no significant difference among seed sources. However, the effect of the interaction between seed source variation and pre-treatment differed significantly in seed germination closing dates and germination percentages. We recommend cold water treatment (submersion of seed at a temperature of 4°C for a 24-h period) for seed germination of T. indica in rural Bangladesh.  相似文献   
5.
In this paper, seed morphology and effects of pre-sowing treatments were studied. Matured seeds of the species were collected from healthy trees in the National Botanical Garden, Bangladesh, and treated with five pre-sowing treatments. The average length, breadth and thickness were found to be 0.56±0.03 cm, 0.44±0.009 cm and 0.26±0.008 cm in Albizia richardiana King and Prain, and 1.32±0.02 cm, 0.55±0.04 cm and 0.11±0.002 cm in Lagerstroemia speciosa L., respectively. Germination was carried out in polybags with a mixture of topsoil, coconut husk compost, coarse sand and fine sand in a ratio of 3:4:1:1. Results revealed that the germination rates of seeds in different pre-sowing treatments were significantly increased compared to those in cold-water treatment in both species. The highest germination rate was found to be 96% in hot-water treatment followed by 87%, 83% and 49% in treatments with scarification, H2SO4 and control in A. richardiana, respectively. However, the highest germination rate (79%) was found in H2SO4 treatment followed by 64%, 62% and 25% in treatments with hot water, scarification and control in L. speciosa, respectively. The lowest germination (35% in A. richardiana and 20% in L. speciosa) was found in cold-water treatment in both cases. Analysis of variance (ANOVA) showed the significant difference among the treatments for both species. It is concluded that hot-water treatment is recommended for seed germination of both species in rural Bangladesh.  相似文献   
6.
OBJECTIVE: To estimate the potential impact of zinc biofortification of rice and wheat on public health in India and to evaluate its cost-effectiveness compared with alternative interventions and international standards. DESIGN: The burden of zinc deficiency (ZnD) in India was expressed in disability-adjusted life years (DALYs) lost. Current zinc intakes were derived from a nationally representative household food consumption survey (30-day recall) and attributed to household members based on adult equivalent weights. Using a dose-response function, projected increased zinc intakes from biofortified rice and wheat were translated into potential health improvements for pessimistic and optimistic scenarios. After estimating the costs of developing and disseminating the new varieties, the cost-effectiveness of zinc biofortification was calculated for both scenarios and compared with alternative micronutrient interventions and international reference standards. SETTING: India. SUBJECTS: Representative household survey (n = 119 554). RESULTS: The calculated annual burden of ZnD in India is 2.8 million DALYs lost. Zinc biofortification of rice and wheat may reduce this burden by 20-51% and save 0.6-1.4 million DALYs each year, depending on the scenario. The cost for saving one DALY amounts to $US 0.73-7.31, which is very cost-effective by standards of the World Bank and the World Health Organization, and is lower than that of most other micronutrient interventions. CONCLUSIONS: Not only may zinc biofortification save lives and prevent morbidity among millions of people, it may also help accommodate the need to economise and to allocate resources more efficiently. Further research is needed to corroborate these findings.  相似文献   
7.
The Organization for Economic Co-operation and Development (OECD) recommends the measurement of specific plant components for compositional assessments of new biotechnology-derived crops. These components include proximates, nutrients, antinutrients, and certain crop-specific secondary metabolites. A considerable literature on the natural variability of these components in conventional and biotechnology-derived crops now exists. Yet the OECD consensus also suggests measurements of any metabolites that may be directly associated with a newly introduced trait. Therefore, steps have been initiated to assess natural variation in metabolites not typically included in the OECD consensus but which might reasonably be expected to be affected by new traits addressing, for example, nutritional enhancement or improved stress tolerance. The compositional study reported here extended across a diverse genetic range of maize hybrids derived from 48 inbreds crossed against two different testers. These were grown at three different, but geographically similar, locations in the United States. In addition to OECD analytes such as proximates, total amino acids and free fatty acids, the levels of free amino acids, sugars, organic acids, and selected stress metabolites in harvested grain were assessed. The major free amino acids identified were asparagine, aspartate, glutamate, and proline. The major sugars were sucrose, glucose, and fructose. The most predominant organic acid was citric acid, with only minor amounts of other organic acids detected. The impact of genetic background and location was assessed for all components. Overall, natural variation in free amino acids, sugars, and organic acids appeared to be markedly higher than that observed for the OECD analytes.  相似文献   
8.
The composition of glyphosate-tolerant (Roundup Ready) soybean 40-3-2 was compared with that of conventional soybean grown in Romania in 2005 as part of a comparative safety assessment program. Samples were collected from replicated field trials, and compositional analyses were performed to measure proximates (moisture, fat, ash, protein, and carbohydrates by calculation), fiber, amino acids, fatty acids, isoflavones, raffinose, stachyose, phytic acid, trypsin inhibitor, and lectin in grain as well as proximates and fiber in forage. The mean values for all biochemical components assessed for Roundup Ready soybean 40-30-2 were similar to those of the conventional control and were within the published range observed for commercial soybean. The compositional profile of Roundup Ready soybean 40-3-2 was also compared to that of conventional soybean varieties grown in Romania by calculating a 99% tolerance interval to describe compositional variability in the population of traditional soybean varieties already on the marketplace. These comparisons, together with the history of the safe use of soybean as a common component of animal feed and human food, lead to the conclusion that Roundup Ready soybean 40-3-2 is compositionally equivalent to and as safe and nutritious as conventional soybean varieties grown commercially.  相似文献   
9.
巴西是如何开发公猪采精技术以及利用每次射精准备好人工授精(AI)所需剂量的? 我们在从Suinosul农场自己饲养的公猪采集和准备精液以用于人工授精(AI)的初级阶段中学到的其中重要一课是,“影响精液采集成功和采精量的重要因素是采精员的技术”。由于我们的员工之前没有猪人工授精方面的经验,于是我们参观了3个拥有AI中心的农场,  相似文献   
10.
Riordan M 《Science (New York, N.Y.)》1992,256(5061):1287-1293
Quarks are widely recognized today as being among the elementary particles of which matter is composed. The key evidence for their existence came from a series of inelastic electron-nucleon scattering experiments conducted between 1967 and 1973 at the Stanford Linear Accelerator Center. Other theoretical and experimental advances of the 1970s confirmed this discovery, leading to the present standard model of elementary particle physics.  相似文献   
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