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251.
252.
北方草甸退化草地治理技术与示范 总被引:3,自引:0,他引:3
国家重点研发计划"北方草甸退化草地治理技术与示范"项目(2016YFC0500600),重点针对我国草甸和草甸草原生态系统所受干扰强度大、退化机理错综复杂、恢复机制及有效治理技术缺乏等问题,从"十三五"规划有关"美丽中国"、"绿色发展"与"生态文明"建设的战略需求出发,着重开展草地退化恢复机理、恢复治理技术、生态产业技术创新应用等三个方面的研究,创建可复制、可移植、系统性的综合治理技术及新型生态产业技术,提出草甸退化草地治理的整套技术方案,为我国草牧业与生态环境和谐发展、牧民稳定增收提供技术支撑。 相似文献
254.
青蒿素生物合成研究进展 总被引:3,自引:0,他引:3
本文论述了青蒿素生物合成的研究进展,涉及生物合成和储藏位点、生物合成的中间体和前体、生物合成的途径以及生物途径代谢调节的关键酶等方面。 相似文献
255.
Liu Chun-Zhao Guo Chen Wang Yuchun Ouyang Fan 《World journal of microbiology & biotechnology》2003,19(5):535-538
Artemisinin, an anti-malarial drug isolated from the annual wormwood Artemisia annua L., has a marked activity against chloroquine-resistant and chloroquine-sensitive strains of Plasmodium falciparum, and is useful in treatment of cerebral malaria. Shoot cultures of Artemisia annua L. were established on Murashige and Skoog basal medium which contained (per litre) 30 g sucrose, 0.5 mg 6-benzyladenine and 0.05 mg naphthaleneacetic acid. Using an optimized combination of sucrose (30 g/l), nitrate (45 mM), inorganic phosphate (200 mg/l), gibberellic acid (7 mg/l) and the ratio of NH4
+-N to NO3
–-N of 1:3, artemisinin production reached 26.7 mg/l after 30 days. This procedure provides a potential alternative for production of artemisinin from in vitro tissue cultures. 相似文献
256.
Clinical translation of scaffold-based bone tissue engineering (BTE) therapy still faces many challenges despite intense investigations and advancement over the years. To address these clinical barriers, it is important to analyse the current technical challenges in constructing a clinically relevant scaffold and subsequent clinical issues relating to bone repair. This review highlights the key challenges hampering widespread clinical translation of scaffold-based vascularised BTE, with a focus on the repair of large non-union defects. The main limitations of current scaffolds include the lack of sufficient vascularisation, insufficient mechanical strength as well as issues relating to the osseointegration of the bioresorbable scaffold and bone infection management. Critical insights on the current trends of scaffold technologies and future directions for advancing next-generation BTE scaffolds into the clinical realm are discussed. Considerations concerning regulatory approval and the route towards commercialisation of the scaffolds for widespread clinical utility will also be introduced. 相似文献
257.
Xiuran Yin Mingwei Cai Yang Liu Guowei Zhou Tim Richter-Heitmann David A. Aromokeye Ajinkya C. Kulkarni Rolf Nimzyk Henrik Cullhed Zhichao Zhou Jie Pan Yuchun Yang Ji-Dong Gu Marcus Elvert Meng Li Michael W. Friedrich 《The ISME journal》2021,15(3):848
Asgard is a recently discovered archaeal superphylum, closely linked to the emergence of eukaryotes. Among Asgard archaea, Lokiarchaeota are abundant in marine sediments, but their in situ activities are largely unknown except for Candidatus ‘Prometheoarchaeum syntrophicum’. Here, we tracked the activity of Lokiarchaeota in incubations with Helgoland mud area sediments (North Sea) by stable isotope probing (SIP) with organic polymers, 13C-labelled inorganic carbon, fermentation intermediates and proteins. Within the active archaea, we detected members of the Lokiarchaeota class Loki-3, which appeared to mixotrophically participate in the degradation of lignin and humic acids while assimilating CO2, or heterotrophically used lactate. In contrast, members of the Lokiarchaeota class Loki-2 utilized protein and inorganic carbon, and degraded bacterial biomass formed in incubations. Metagenomic analysis revealed pathways for lactate degradation, and involvement in aromatic compound degradation in Loki-3, while the less globally distributed Loki-2 instead rely on protein degradation. We conclude that Lokiarchaeotal subgroups vary in their metabolic capabilities despite overlaps in their genomic equipment, and suggest that these subgroups occupy different ecologic niches in marine sediments.Subject terms: Archaeal physiology, Stable isotope analysis, Microbial ecology 相似文献
258.
259.
Co-lyophilization with ligands and lyoprotectants markedly activated horseradish and soybean peroxidases in the oxidation of guaiacol in organic solvents (Dai & Klibanov (1999) Proc. Natl. Acad. Sci. USA
96: 9475–9478). However, such excipients gave little or no activation of these enzymes in non-specific reactions, sulfoxidation of thioanisole and epoxidation of styrene, presumably because they do not require a precise fine tuning of the enzyme active site. 相似文献