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951.
转基因技术是近20年发展起来的在体内研究基因功能的分子生物学方法之一,近年来在原有技术的基础上,取得了许多新进展。综述条件转基因技术研究的新进展。阐明转基因的诱导表达系统争条件基因剔除系统的原理、操作过程以及这两系统各自的优缺点。 相似文献
952.
生物技术与生物学实验技术是两个内涵不同的概念。我们在生物教学以及生物有关教材的编写过程中,应给以区别和注意。 相似文献
953.
Industrial Ecology and Ecological Engineering 总被引:1,自引:0,他引:1
David Rogers Tilley 《Journal of Industrial Ecology》2003,7(2):13-32
Ecological engineering (EE) and industrial ecology (IE) strive to balance humanity's activities with nature. The disciplines have emerged separately but share theoretical foundations and philosophies on how to address today's complex environmental issues. Although EE and IE share motive, goals, theories, and philosophies, there are many differences. These similarities and differences may make for a strong symbiotic relationship between the two fields. The goals of this article are (1) to compare and contrast the two fields to identify opportunities for collaboration and integration and (2) to suggest three cross-disciplinary focal areas that bridge EE and IE.
The first symbiotic area, ecosystem engineering for byproduct recovery, is defined as the design, creation, and management of living ecosystems (e.g., forests, wetlands) that utilize the by-products of industrial systems. Examples of this exist, including constructed wetlands for lead recovery and phyto-mining of nickel tailings. The second symbiotic focus is entitled "ecosystem analogues for industrial ecology", which fits with a founding principle of IE to strive to have industry emulate the energy efficiencies and material cycles of natural ecosystems. This focal area quantifies the ecological analogy and exploits the tremendous library of design alternatives that nature has developed over thousands of years to deal with varied resource situations. The third focal area is termed "eco-system information engineering." The means by which living ecosystems have created robust knowledge systems and information cycles should be understood in terms useful for managing current society's information explosion. As industrial society evolves toward the information society, holistic models are needed that account for the available energy and material resources required to operate effective information ecosystems, such as service industries. 相似文献
The first symbiotic area, ecosystem engineering for byproduct recovery, is defined as the design, creation, and management of living ecosystems (e.g., forests, wetlands) that utilize the by-products of industrial systems. Examples of this exist, including constructed wetlands for lead recovery and phyto-mining of nickel tailings. The second symbiotic focus is entitled "ecosystem analogues for industrial ecology", which fits with a founding principle of IE to strive to have industry emulate the energy efficiencies and material cycles of natural ecosystems. This focal area quantifies the ecological analogy and exploits the tremendous library of design alternatives that nature has developed over thousands of years to deal with varied resource situations. The third focal area is termed "eco-system information engineering." The means by which living ecosystems have created robust knowledge systems and information cycles should be understood in terms useful for managing current society's information explosion. As industrial society evolves toward the information society, holistic models are needed that account for the available energy and material resources required to operate effective information ecosystems, such as service industries. 相似文献
954.
955.
应用GIS技术进行野生动物生境研究概况及展望 总被引:14,自引:1,他引:13
1 GIS的特性及对野生动物生境研究产生的影响近年来 ,生物多样性的研究和保护已在多层次、多水平上展开 [2 7] ,其中对野生动物生境的保护和研究是非常重要的一方面。生境 ( habitat)一词首先由美国的 Grinnel于 1 91 7年提出 ,指的是生物的居住场所 ,即生物个体、种群或群落能在其中完成生命过程的空间 [11]。自然界的生物都有它特定的生活环境 ,都有各自要求的适宜的环境条件。由于生物种类繁多 ,生物和环境、生物和生物之间的关系错综复杂 ,因此 ,野生动物生境的保护涉及到许多与时间动态及空间格局相关的问题。传统动物生态学和动物… 相似文献
956.
双液相系统酶化学技术制取茶色素 总被引:13,自引:0,他引:13
应用双液相酶化学技术研究茶色素的形成与制取,并以单液(水)相系统进行茶多酚酶促氧化制取茶色素为对照,引入氧载体后,构成了双液相酶化学氧化系统,对其中溶解氧浓度,PPO活性,TFs,TRs含量的变化和HPLC图谱等分析研究,制品中TFs的HPLC图谱可知:TOP-1中TFs的峰高和峰面积均高于TOP-2制品中TFs,尤以TFG与TFDG较高,TOP-1制品中儿茶素类残留量较对照少,尤其是简单儿茶素的列留量(如DL-C(-)-EC)少得更多。 相似文献
957.
The mammalian Mediator complex 总被引:2,自引:0,他引:2
Conaway JW Florens L Sato S Tomomori-Sato C Parmely TJ Yao T Swanson SK Banks CA Washburn MP Conaway RC 《FEBS letters》2005,579(4):904-908
958.
959.
John A. Pickett Gudbjorg I. Aradottír Michael A. Birkett Toby J. A. Bruce Antony M. Hooper Charles A. O. Midega Huw D. Jones Michaela C. Matthes Johnathan A. Napier Jimmy O. Pittchar Lesley E. Smart Christine M. Woodcock Zeyaur R. Khan 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2014,369(1639)
To reduce the need for seasonal inputs, crop protection will have to be delivered via the seed and other planting material. Plant secondary metabolism can be harnessed for this purpose by new breeding technologies, genetic modification and companion cropping, the latter already on-farm in sub-Saharan Africa. Secondary metabolites offer the prospect of pest management as robust as that provided by current pesticides, for which many lead compounds were, or are currently deployed as, natural products. Evidence of success and promise is given for pest management in industrial and developing agriculture. Additionally, opportunities for solving wider problems of sustainable crop protection, and also production, are discussed. 相似文献
960.
精原干细胞移植为研究精子发生、雄性生殖能力及新型转基因技术奠定了基础.尽管已利用小鼠建立了较成熟的移植技术体系,白消安受体制备法和曲细精管及睾丸网移植法已得到广泛应用,但白消安可导致动物较高的死亡率,局部射线照射和无内源性精子发生受体动物的制备费用较昂贵,热处理受体制备法应用范围较窄且效果不稳定;三种移植方法均对操作有较高的技术要求,曲细精管、睾丸输出管移植需要显微注射装置,而睾丸网移植需要超声仪的辅助.而且,移植效果在不同实验间、物种间差异较大,移植效率有待提高,对移植排斥反应的认识也有待进一步深入.对睾丸结构和精原干细胞生物学特性的深入研究,将有助于建立更简单高效的受体制备和移植的方法. 相似文献