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This paper reviews a number of recent social science publications on the nature and causes of food insecurity in low and middle-income countries. The focus is on one specific element of food insecurity, vitamin A deficiency, which is widespread in developing countries and causes blindness and early death among millions of children. A new approach in the fight against vitamin A deficiency is `Golden Rice'. The paper explores the pros and cons of this recently developed transgenic rice variety, and tries to answer the question whether in this particular case, genetic modification technology provides a solution to food insecurity. It is concluded that Golden Rice is one of the options available, but not necessarily the most effective one. 相似文献
94.
ABSTRACT:?Xylanases are hydrolases depolymerizing the plant cell wall component xylan, the second most abundant polysaccharide. The molecular structure and hydrolytic pattern of xylanases have been reported extensively and the mechanism of hydrolysis has also been proposed. There are several models for the gene regulation of which this article could add to the wealth of knowledge. Future work on the application of these enzymes in the paper and pulp, food industry, in environmental science, that is, bio-fueling, effluent treatment, and agro-waste treatment, etc. require a complete understanding of the functional and genetic significance of the xylanases. However, the thrust area has been identified as the paper and pulp industry. The major problem in the field of paper bleaching is the removal of lignin and its derivatives, which are linked to cellulose and xylan. Xylanases are more suitable in the paper and pulp industry than lignin-degrading systems. 相似文献
95.
黄土高原草地畜牧业产业形成与发展的牧草生产力基础 总被引:7,自引:0,他引:7
在黄土高原197个区县土地利用方式重新规划的基础上,对黄土高原畜牧业产业形成与发展的牧草生产潜力进行了分析预测。结果表明:规划的牧、林、农、果用地占生产用地的比例分别是草地44%、林地22%、基本农田20%、果园14%;197个区县草地牧草生产、作物秸秆、草田轮作和果园种草预测的总牧草饲料生产潜力达104881028t/a(其中,草地牧草生产潜力约占45%,达47196462.7t/a),可载畜104881028个羊单位/a(其中草地可载畜47196462.7个羊单位/a)。按1999年不变价格计算,黄土高原预测畜牧业总产值将达到5244051万元RMB/a,是1999年畜牧业总产值的5.3倍,超过1999年黄土高原农业总产值14%。农业人口人均预测畜牧业产值大于l000元的区县占59%;小于l000元的区县占41%。此外,预测的农业总产值将达到l147.2234亿元RMB/a,其中畜牧业、果业、林业和农业产值占农业总产值的比重分别是46%、27%、14%和13%。随着畜牧业产业链的逐步建立与完善,产业发展布局的日趋合理,黄土高原畜牧业生产总值将有较大幅度的提高,黄土高原生态环境将有进一步的改善。黄土高原草地畜牧业蕴藏着巨大的发展潜力,有望成为黄土高原优化的生产一生态新产业带建制中的支柱产业。 相似文献
96.
林德贵 《中国实验动物学杂志》2010,(11):13-16
我国宠物业是一个朝阳产业,发展速度快,问题多,整体水平不高,以市场化为主。宠物业的发展应当是全面的,逐步走向成熟。我们在宠物饲养观念、宠物在社会生活中的作用研究、宠物疾病防治、宠物与人共患疾病的关注度、宠物医疗、宠物药品、宠物食品、宠物医学教育等全方位面临机会和挑战。今后,中国大陆的宠物业在宠物疫苗研制、新宠物药品研发、新中兽药研制和推广、高质量宠物食品和处方食品生产、高水平的宠物医疗机构的扩展、和宠物与人类比较医学上必将得到很大的发展机会。 相似文献
97.
We developed 10 polymorphic microsatellite loci for the Japanese paper wasp Polistes rothneyi using the magnetic particle method. Eight of the 10 loci tested were highly polymorphic, having four to eight alleles in P. rothneyi with an expected heterozygosity of 0.60–0.75. They also appeared to be applicable to other related species such as Polistes jokahamae. These loci can be used to study parameters concerning genetic relatedness such as worker reproduction and kin structure. 相似文献
98.
Matsuzaki S Yasuda Y Kobayashi S Koyama Y Kawamoto K Katayama T Tohyama M 《Biochemical and biophysical research communications》2007,358(2):540-544
The present study has examined the effect of metals, such as iron and copper on the cytotoxicity of amyloid beta protein 1-40 (Abeta40). First, we showed that monomeric Abeta40 has stronger cytotoxicity than various type of aggregated Abeta40. Next we showed the addition of metals into the monomeric Abeta40 reduced the cytotoxicity of either monomeric Abeta40 or metals (iron and copper) although the addition of metals into monomeric Abeta40 resulted in a marked increase of aggregated form of Abeta40, which composed of beta-sheeted Abeta40 and Abeta40 aggregation not characterized by beta-sheet fibrils (coagrated Abeta40). Taken together, the metals and monomeric Abeta40 affect on each other and cause the reduction of their cell toxicity. 相似文献
99.
Salmonella spp. bacteria are responsible for some of the most important zoonoses worldwide. Because Dermanyssus gallinae (DeGeer) (Acari: Dermanyssidae) has been recently reported to be an experimental vector of Salmonella Enteritidis, it would be of benefit to evaluate the presence of this bacterium in mites. A molecular detection tool associating a simple filter-based DNA preparation with a specific 16S rDNA Salmonella sp. polymerase chain reaction (PCR) amplification was described. The limit of detection with this method was 2 x 10(4) bacteria per mite. To adapt this technique for large-scale studies, two sizes of mite pools were tested and a preliminary investigation was carried out on mites from 16 currently or previously contaminated farms. Mites sampled from one farm of each type were positive for Salmonella, suggesting that Dermanyssus could act as a reservoir between flocks. In further investigations, it will be necessary to carry out a large-scale study to assess the role of D. gallinae in the epidemiology of avian salmonellosis. 相似文献
100.
抗菌肽及其工业应用前景 总被引:1,自引:0,他引:1
抗菌肽是生物体内经诱导产生的一种对抗外源性致病菌作用的防御性小分子多肽,广泛存在于动植物和微生物体内。其分子量一般在4000Da左右,带正电荷,由30~40个氨基酸组成。抗菌肽一般都具有耐热性,100℃温度下活性最长可保持30min以上。抗菌肽具广谱抗菌活性,通过破坏细胞膜等作用,可以抑制革兰氏阴性菌、革兰氏阳性菌、真菌,有些抗菌肽还具有抗原虫、病毒及抗癌功能。抗菌肽在工业应用中展示出了广阔的前景。 相似文献