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排序方式: 共有243条查询结果,搜索用时 15 毫秒
91.
Wayne Martindale 《Biotechnology & genetic engineering reviews》2013,29(1):115-134
The emergence of food security as a key policy issue in developed nations has been concomitant with the need to reduce greenhouse gas emissions and the implementation of Environmental Management Systems in primary industries. Biotechnological interventions such as biorefinery platforms that produce chemicals and fuels provide opportunities to reconcile the security and environmental sustainability criteria increasingly sought after by governments. Indeed, sustainable and more carbon neutral options have been positively benchmarked against scenarios based solely on petrochemical feedstocks. Notably, biotechnology companies are beginning to use Environmental Management Systems employed by other industries to advocate the benefits of green technologies that employ GM, industrial enzymes and bio-materials. Management systems such as Life Cycle Analysis are providing a powerful means to measure benefits and augment change in the biotechnology sector. These methods are discussed here in the context of the emergent 21st Century debates on security. The evidence presented leads to a conclusion where biotechnologies are likely to offer increasingly high impact options for sustainability and security criteria required for food and fuel supply. 相似文献
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Subramanya Srikantan Kotb Abdelmohsen Eun Kyung Lee Kumiko Tominaga Sarah S. Subaran Yuki Kuwano Ritu Kulshrestha Rohit Panchakshari Hyeon Ho Kim Xiaoling Yang Jennifer L. Martindale Bernard S. Marasa Mihee M. Kim Robert P. Wersto Fred E. Indig Dipanjan Chowdhury Myriam Gorospe 《Molecular and cellular biology》2011,31(18):3790-3801
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Tominaga K Srikantan S Lee EK Subaran SS Martindale JL Abdelmohsen K Gorospe M 《Molecular and cellular biology》2011,31(20):4219-4231
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Deuterostome evolution: early development in the enteropneust hemichordate, Ptychodera flava 总被引:1,自引:1,他引:0
SUMMARY Molecular and morphological comparisons indicate that the Echinodermata and Hemichordata represent closely related sister‐phyla within the Deuterostomia. Much less is known about the development of the hemichordates compared to other deuterostomes. For the first time, cell lineage analyses have been carried out for an indirect‐developing representative of the enteropneust hemichordates, Pty‐ chodera flava. Single blastomeres were iontophoretically labeled with DiI at the 2‐ through 16‐cell stages, and their fates followed through development to the tornaria larval stage. The early cleavage pattern of P. flava is similar to that of the direct‐developing hemichordate, Saccoglossus kowalevskii, as well as that displayed by indirect‐developing echinoids. The 16‐celled embryo contains eight animal “mesomeres,” four slightly larger “macromeres,” and four somewhat smaller vegetal “micromeres.” The first cleavage plane was not found to bear one specific relationship relative to the larval dorsoventral axis. Although individual blastomeres generate discrete clones of cells, the appearance and exact locations of these clones are variable with respect to the embryonic dorsoventral and bilateral axes. The eight animal mesomeres generate anterior (animal) ectoderm of the larva, which includes the apical organ; however, contributions to the apical organ were found to be variable as only a subset of the animal blastomeres end up contributing to its formation and this varies from embryo to embryo. The macromeres generate posterior larval ectoderm, and the vegetal micromeres form all the internal, endomesodermal tissues. These blastomere contributions are similar to those found during development of the only other hemichordate studied, the direct‐developing enteropneust, S. kowalevskii. Finally, isolated blastomeres prepared at either the two‐ or the four‐cell stage are capable of forming normal‐appearing, miniature tornaria larvae. These findings indicate that the fates of these cells and embryonic dorsoventral axial properties are not committed at these early stages of development. Comparisons with the developmental programs of other deuterostome phyla allow one to speculate on the conservation of some key developmental events/mechanisms and propose basal character states shared by the ancestor of echinoderms and hemichordates. 相似文献
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We describe a method for producing specific PCR primers directly from PCR product, bypassing the usual need to know the primer sequence. Lack of abundance of primers derived from a PCR product is compensated for by the incorporation of an arbitrary 5'TAG sequence which acts as a surrogate template target for the bulk amplification phase. We use the technique to amplify clonospecific rearranged immunoglobulin genes, which have applications as markers of lymphoid neoplasms for tracing the success of therapy. The principle may have wider application wherever conserved and variable regions of DNA are juxtaposed. 相似文献