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991.
白腐菌的研究进展及其在重金属修复中的展望 总被引:3,自引:0,他引:3
白腐菌是一类特殊的丝状真菌,能降解多种污染物质,具有广谱、彻底、高效、无专一性的 特点,在生物修复中有广阔的应用前景。综述了白腐菌的分类、酶系、降解机理以及应用于有机 物污染的研究现状,特别介绍了白腐菌在重金属污染的生物修复的应用进展情况,包括白腐菌吸 附重金属的原理、在重金属污染的废水中的研究应用现状及在修复重金属污染土壤中需考虑的 因素。同时展望了白腐菌在重金属污染及复合污染的生物修复中的应用前景。 相似文献
992.
根据福建山地的气候生态特征和茶树生物学特性,以茶树安全生育的气象指标、茶叶产量形成的热量指标和优质茶形成的关键气象因子为原则,运用气温场计算方程上机计算,结果是:(1)大叶种茶树:闽西南海拔400~560m,闽中海拔200~400m为最适宜带;闽西南海拔600~874m,闽中和闽东北海拔200~600m为适宜带。(2)中、小叶种茶树:闽西南海拔600~874m,闽中、闽东北海拔200~600m为最适宜带;闽西南海拔1200m,闽中海拔1100m,闽北、闽东北海拔600~900m为适宜带;闽西南海拔1500~1700m,闽中海拔1200~1500m,闽北、闽东北海拔950~1200m为次适宜带。据此,作者提出科学开发福建山地,发展茶叶的三条配套技术措施。 相似文献
993.
根据GenBank上WSSV囊膜蛋白基因vp19和vp28的序列,设计并合成两对引物,PCR扩增得到vp19和vp28两基因,大小分别为370bp和630bp.通过EcoRI位点连接两基因,再按正确的阅读框插入表达载体pET-22b(+)中,构建出重组表达载体pET-vp(19+28)并转化大肠杆菌BL21(DE3).基因工程菌株35℃IPTG诱导,表达产物经SDS-PAGE检测显示有与预期大小41kDa相吻合的融合蛋白带.用Ni2+-柱纯化的基因工程蛋白免疫新西兰大白兔制备抗血清,进行螯虾活体中和病毒实验,结果表明抗血清对WSSV的中和效率达到了100%. 相似文献
994.
《Fungal biology》2020,124(12):1013-1023
The vegetative mycelium of Agaricus bisporus supplies developing white button mushrooms with water and nutrients. However, it is not yet known which part of the mycelium contributes to the feeding of the mushrooms and how this depends on growth conditions. Here we used photon counting scintillation imaging to track translocation of the 14C-radiolabeled metabolically inert amino acid analogue α-aminoisobutyric acid (14C-AIB). Translocation to the periphery of the mycelium was observed in actively growing vegetative mycelium with a velocity of up to 6.6 mm h−1, which was 30-fold higher than the growth rate. Furthermore, 14C-AIB translocated to neighboring colonies after fusion by anastomosis depending on the relative growth rate in these colonies. When mushrooms started to develop, translocation of 14C-AIB was redirected to the fruiting bodies via mycelium and hyphal cords. More abundant mycelial cord formation and a 5-fold higher rate of translocation was observed for cultures growing directionally from inoculum located at one side of the substrate, when compared to non-directional growth (inoculum mixed throughout the substrate). The maximum translocation distance was also greater (≥50 and 22 cm, respectively). In conclusion, 14C-AIB translocation switches between vegetative growth and towards developing mushrooms, especially via cords and when source–sink relationships change. 相似文献
995.
This research explores the intertwined construction of race and gender in a wide variety of white supremacist newsletters and periodicals published between 1969 and 1993. While traditional accounts of the white supremacist movement treat it as a movement concerned with race relations, I read this discourse as a site of the construction of race. Additionally, I argue that race and gender are inextricably linked. Exploring how meaning works in white supremacist discourse, this research provides an analysis of the construction of racial and gender difference within the framework of the equality versus difference dichotomy. Within this framework, difference requires hierarchy, so that any effort to redress inequality is posited as a threat to difference. The primary project of the white supremacist movement is the construction of white racial and gender identities as naturalized and hierarchized differences. 相似文献
996.
Lili Sun Mengshi Zhang Xiaomei Liu Qianzhuo Mao Chen Shi Leon V. Kochian Hong Liao 《植物学报(英文版)》2020,62(7):984-997
On acid soils, the trivalent aluminium ion (Al3+) predominates and is very rhizotoxic to most plant species. For some native plant species adapted to acid soils including tea (Camellia sinensis), Al3+ has been regarded as a beneficial mineral element. In this study, we discovered that Al3+ is actually essential for tea root growth and development in all the tested varieties. Aluminum ion promoted new root growth in five representative tea varieties with dose‐dependent responses to Al3+ availability. In the absence of Al3+, the tea plants failed to generate new roots, and the root tips were damaged within 1 d of Al deprivation. Structural analysis of root tips demonstrated that Al was required for root meristem development and activity. In situ morin staining of Al3+ in roots revealed that Al mainly localized to nuclei in root meristem cells, but then gradually moved to the cytosol when Al3+ was subsequently withdrawn. This movement of Al3+ from nuclei to cytosols was accompanied by exacerbated DNA damage, which suggests that the nuclear‐targeted Al primarily acts to maintain DNA integrity. Taken together, these results provide novel evidence that Al3+ is essential for root growth in tea plants through maintenance of DNA integrity in meristematic cells. 相似文献
997.
998.
《Cytokine》2015,76(2):272-279
Over the past few decades, our understanding of the role of adipose tissue has changed dramatically. Far from simply being a site of energy storage or a modulator of the endocrine system, adipose tissue has emerged as an important regulator of multiple important processes including inflammation. Adipokines are a diverse family of soluble mediators with a range of specific actions on the immune response. Autoimmune diseases are perpetuated by chronic inflammatory responses but the exact etiology of these diseases remains elusive. While researchers continue to investigate these causes, millions of people continue to suffer from chronic diseases. To this end, an increased interest has developed in the connection between adipose tissue-secreted proteins that influence inflammation and the onset and perpetuation of autoimmunity. This review will focus on recent advances in adipokine research with specific attention on a subset of adipokines that have been associated with autoimmune diseases. 相似文献
999.
1000.
Irpex
lacteus was genetically transformed using an laccase expression vector to get increased laccase producing strains. Stable integration
of the vector was confirmed by PCR using the vector-specific primers, and the transformants showed increased laccase activities.
When the transformants were grown with several endocrine disrupting chemicals, laccase activity of each transformant was induced
up to six times higher than that of the wild type. They showed increased degrading activities against EDCs as well as increased
removal rates of estrogenic activities generated by the EDCs than the wild type, and the laccase expression was increased
during the degradations of the EDCs. 相似文献