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181.
182.
Creation of ecdysone receptor chimeras in plants for controlled regulation of gene expression 总被引:10,自引:0,他引:10
A. Martinez C. Sparks P. Drayton J. Thompson A. Greenland I. Jepson 《Molecular & general genetics : MGG》1999,261(3):546-552
Transformation with a chimeric receptor containing the glucocorticoid transactivation and DNA-binding domains fused to an
ecdysteroid receptor ligand-binding domain permits ecdysone agonist-inducible gene expression in monocotyledonous plant cells.
The inducible system is based on the specific activation of a chimeric receptor containing the ligand-binding domain of the
Heliothis virescens ecdysteroid receptor and the inducer RH5992 (a 20-hydroxyecdysone agonist). RH5992 is an non-steroidal agrochemical with
a high specificity for lepidopteran ecdysone receptors. Addition of RH5992 to transformed cells results in high levels of
inducible expression in a ligand-specific manner, particularly when the effector receptor is coupled to the strong transactivator
VP16. A chimeric construct containing the Drosophila ecdysone ligand-binding domain failed to activate reporter gene activity with RH5992, while activation was observed in the
presence of muristeroneA. The system described provides the basis for an inducible gene expression system that is compatible
with agricultural use.
Received: 24 September 1998 / Accepted: 15 January 1999 相似文献
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Erythropoiesis during pregnancy and lactation. I. Effect of various hormones on erythropoiesis during lactation 总被引:1,自引:0,他引:1
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Values-led conservation 总被引:1,自引:0,他引:1
In international nature conservation policy, value‐arguments based on science and economic rationalism increasingly overshadow the aesthetic and ethical arguments that originally inspired the conservation movement. We argue that this trend risks removing conservation from the public realm, in part because it facilitates the adoption by nongovernment conservation bodies of corporate values and/or their integration with government bureaucracies. By contrast, the explicit recognition of aesthetic and ethical values would complement arguments based on science and economic utility. We subscribe to a reformist view of globalization that accepts the inevitability of a globalizing world but argues that the process needs humanizing by incorporating quality of life values in the policy process. We argue that re‐emphasis of aesthetic and ethical arguments in international conservation policy would contribute to this goal by reasserting links between conservation bodies and the public, thereby leading to more effective action on the ground. 相似文献
187.
A M Jepson 《BMJ (Clinical research ed.)》1981,282(6282):2112-2113
Parents for Children is a specialist adoption agency set up to find homes for children with special needs--that is, those with physical, mental, and emotional handicaps; older children; and sibling groups. Of the first 38 children placed, one child died and six placements broke down, although four children were later re-placed. Almost all the children referred to the agency had been in care for most of their lives. A full assessment of each child is necessary before placement, but in several cases the medical assessment in care had been inadequate. Many of the prospective parents themselves had serious medical conditions. The agency has proved that homes can be found for children in need, but there have been problems and parents require advice and support in the management of the children after placement. 相似文献
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