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排序方式: 共有284条查询结果,搜索用时 15 毫秒
201.
Ira Handayani Hamada Saad Shanti Ratnakomala Puspita Lisdiyanti Wien Kusharyoto Janina Krause Andreas Kulik Wolfgang Wohlleben Saefuddin Aziz Harald Gross Athina Gavriilidou Nadine Ziemert Yvonne Mast 《Marine drugs》2021,19(6)
Indonesia is one of the most biodiverse countries in the world and a promising resource for novel natural compound producers. Actinomycetes produce about two thirds of all clinically used antibiotics. Thus, exploiting Indonesia’s microbial diversity for actinomycetes may lead to the discovery of novel antibiotics. A total of 422 actinomycete strains were isolated from three different unique areas in Indonesia and tested for their antimicrobial activity. Nine potent bioactive strains were prioritized for further drug screening approaches. The nine strains were cultivated in different solid and liquid media, and a combination of genome mining analysis and mass spectrometry (MS)-based molecular networking was employed to identify potential novel compounds. By correlating secondary metabolite gene cluster data with MS-based molecular networking results, we identified several gene cluster-encoded biosynthetic products from the nine strains, including naphthyridinomycin, amicetin, echinomycin, tirandamycin, antimycin, and desferrioxamine B. Moreover, 16 putative ion clusters and numerous gene clusters were detected that could not be associated with any known compound, indicating that the strains can produce novel secondary metabolites. Our results demonstrate that sampling of actinomycetes from unique and biodiversity-rich habitats, such as Indonesia, along with a combination of gene cluster networking and molecular networking approaches, accelerates natural product identification. 相似文献
202.
Linda S. Heath Pekka E. Kauppi Peter Burschel Heinz -Detlev Gregor Robert Guderian Gundolf H. Kohlmaier Susanne Lorenz Dieter Overdieck Florian Scholz Harald Thomasius Michael Weber 《Water, air, and soil pollution》1993,70(1-4):55-69
Temperate forests currently cover about 600 MHa, about half of their potential. Almost all these forests have been directly impacted by humans. The total living biomass in trees (including roots) was estimated to contain 33.7 Gt C. The total C pool for the entire forest biome was estimated as 98.8 Gt. The current net sink flux of biomass was calculated at 205 Mt yr?1, with a similar amount removed in harvests for manufacture into various products. The major cause of this C sink is forest regrowth. Forest regrowth is possible because fossil fuels are the major source of energy in temperate countries, instead of fuelwood. Future C in these forests will be greatly influenced by human activity. Options to sequester more C include conservation of forest resources, activities that increase forest productivity such as adopting rotation ages to optimize C production, afforestation, improvement of wood utilization, and waste management. 相似文献
203.
Hund A Gollnick N Sauter-Louis C Neubauer-Juric A Lahm H Büttner M 《Veterinary microbiology》2012,154(3-4):247-256
The compulsory vaccination campaign against Bluetongue virus serotype eight (BTV-8) in Germany was exercised in the state of Bavaria using three commercial monovalent inactivated vaccines given provisional marketing authorisation for emergency use. In eleven Bavarian farms representing a cross sectional area of the state the immune reactions of sheep and cattle were followed over a two year period (2008-2009) using cELISA, a serum neutralisation test (SNT) and interferon gamma (IFN-γ) ELISPOT. For molecular diagnostics of BTV genome presence two recommended real time quantitative RT-PCR protocols were applied. The recommended vaccination scheme led to low or even undetectable antibody titers (ELISA) in serum samples of both cattle and sheep. A fourfold increase of the vaccine dose in cattle, however, induced higher ELISA titers and virus neutralising antibodies. Accordingly, repeated vaccination in sheep caused an increase in ELISA-antibody titers. BTV-8 neutralising antibodies occurred in most animals only after multiple vaccinations in the second year of the campaign. The secretion of interferon gamma (IFN-γ) in ELISPOT after in vitro re-stimulation of PBMC of BTV-8 vaccinated animals with BTV was evaluated in the field for the first time. Sera of BTV-8 infected or vaccinated animals neutralising BTV-8 could also neutralise an Italian BTV serotype 1 cell culture adapted strain and PBMC of such animals secreted IFN-γ when stimulated with BTV-1. 相似文献
204.
Darius Phiri Pierre Ackerman Brand Wessels Ben du Toit Marie Johansson Harald Säll 《Southern Forests》2015,77(4):255-262
In the water-scarce environment of South Africa, drought-tolerant eucalypt species have the potential to contribute to the timber and biomass resource. Biomass functions are a necessary prerequisite to predict yield and carbon sequestration. In this study preliminary biomass models for Eucalyptus cladocalyx, E. gomphocephala and E. grandis · E. camaldulensis from the dry West Coast of South Africa were developed. The study was based on 33 trees, which were destructively sampled for biomass components (branchwood, stems, bark and foliage). Simultaneous regression equations based on seemingly unrelated regression were fitted to estimate biomass while ensuring additivity. Models were of the classical allometric form, ln(Y) = a+x1ln(dbh)+x2ln(h), of which the best models explained between 70% and 98% of the variation of the predicted biomass quantities. A general model for the pooled data of all species showed a good fit as well as robust model behaviour. The average biomass proportions of the stemwood, bark, branches and foliage were 60%, 6%, 29% and 5%, respectively. 相似文献
205.
An ethno-pharmacognostic survey was carried out in one of the smallest ethnic and linguistic groups in Europe: the Istro-Romanians of the village of Zejane (in Croatia), which has a population of approximately 140 persons, mainly elderly. Using an intensive field participant observation methodology, we recorded about 60 remedies of the local folk pharmacopoeia, and mainly derived from plants. Among them, the uncommon traditions to use homemade vinegar from wild apple (Malus sylvestris) and Cornelian cherries (Cornus mas) for diverse medical purposes, and houseleek (Sempervivum tectorum) against ear pains have been briefly discussed. 相似文献
206.
207.
Anderson MS Venanzi ES Klein L Chen Z Berzins SP Turley SJ von Boehmer H Bronson R Dierich A Benoist C Mathis D 《Science (New York, N.Y.)》2002,298(5597):1395-1401
208.
Heikenwalder M Zeller N Seeger H Prinz M Klöhn PC Schwarz P Ruddle NH Weissmann C Aguzzi A 《Science (New York, N.Y.)》2005,307(5712):1107-1110
Prions typically accumulate in nervous and lymphoid tissues. Because proinflammatory cytokines and immune cells are required for lymphoid prion replication, we tested whether inflammatory conditions affect prion pathogenesis. We administered prions to mice with five inflammatory diseases of the kidney, pancreas, or liver. In all cases, chronic lymphocytic inflammation enabled prion accumulation in otherwise prion-free organs. Inflammatory foci consistently correlated with lymphotoxin up-regulation and ectopic induction of FDC-M1+ cells expressing the normal cellular prion protein PrPC. By contrast, inflamed organs of mice lacking lymphotoxin-alpha or its receptor did not accumulate the abnormal isoform PrPSc, nor did they display infectivity upon prion inoculation. By expanding the tissue distribution of prions, chronic inflammatory conditions may act as modifiers of natural and iatrogenic prion transmission. 相似文献
209.
210.
Saeed Muhammad Farhan Baćanović Jelena Bruns Christian Schmidt Harald Finckh Maria Renate 《植物病害和植物保护杂志》2017,124(4):331-337
Journal of Plant Diseases and Protection - A survey was conducted in Germany during 2009–2012 on seed health of organic pea and faba beans and their harvested progeny seed on up to 32 organic... 相似文献