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排序方式: 共有400条查询结果,搜索用时 15 毫秒
61.
Pathways of bacterial contamination during egg incubation and larval rearing of turbot, Scophthalmus maximus 总被引:1,自引:0,他引:1
Overall microbial levels in the water system of a turbot farm were similar to those found in regular sea-water. At the end of an incubation period, however, the numbers of colony-forming units (CFU) in Artemiu cultures and turbot eg incubation jars were up to four orders of magnitude higher than sea-water level. Rinsing of the foot organisms (rotifers) prior to feeding them to turbot larvae, however, significantly reduced bacterial numbers, thus reducing the number of cross-contaminations. Several species of Aeromonas, Pseudomonas and Vibrio among others, were identified in the eggs and larvae, or in the water in which these were incubated. Scanning electron microscop shows that the surface of unfertilized turbot eggs is a breeding ground for bacteria; the removal of these eggs from incubation jars is therefore recommended. The epidermis of turbot larvae was virtually free ofmicroorganisms. 相似文献
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Corrado Marcenò Riccardo Guarino Javier Loidi Mercedes Herrera Maike Isermann Ilona Knollová Lubomír Tichý Rossen T. Tzonev Alicia Teresa Rosario Acosta Úna FitzPatrick Dmytro Iakushenko John A. M. Janssen Borja Jiménez‐Alfaro Zygmunt Kącki Iva Keizer‐Sedláková Vitaliy Kolomiychuk John S. Rodwell Joop H. J. Schaminée Urban Šilc Milan Chytrý 《应用植被学》2018,21(3):533-559
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Ulrich Nowitzki Gabriel Gelius-Dietrich Maike Schwieger Katrin Henze William Martin 《European journal of biochemistry》2004,271(20):4123-4131
Two chloroplast phosphoglycerate kinase isoforms from the photosynthetic flagellate Euglena gracilis were purified to homogeneity, partially sequenced, and subsequently cDNAs encoding phosphoglycerate kinase isoenzymes from both the chloroplast and cytosol of E. gracilis were cloned and sequenced. Chloroplast phosphoglycerate kinase, a monomeric enzyme, was encoded as a polyprotein precursor of at least four mature subunits that were separated by conserved tetrapeptides. In a Neighbor-Net analysis of sequence similarity with homologues from numerous prokaryotes and eukaryotes, cytosolic phosphoglycerate kinase of E. gracilis showed the highest similarity to cytosolic and glycosomal homologues from the Kinetoplastida. The chloroplast isoenzyme of E. gracilis did not show a close relationship to sequences from other photosynthetic organisms but was most closely related to cytosolic homologues from animals and fungi. 相似文献
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Mixotrophy in the terrestrial green alga Apatococcus lobatus (Trebouxiophyceae,Chlorophyta)
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The green microalga Apatococcus lobatus is widely distributed in terrestrial habitats throughout many climatic zones. It dominates green biofilms on natural and artificial substrata in temperate latitudes and is regarded as a key genus of obligate terrestrial consortia. Until now, its isolation, cultivation and application as a terrestrial model organism has been hampered by slow growth rates and low growth capacities. A mixotrophic culturing approach clearly enhanced the accumulation of biomass, thereby permitting the future application of A. lobatus in different types of bio‐assays necessary for material and biofilm research. The ability of A. lobatus to grow mixotrophically is assumed as a competitive advantage in terrestrial habitats. 相似文献
68.
The Nox1/4 Dual Inhibitor GKT137831 or Nox4 Knockdown Inhibits Angiotensin‐II‐Induced Adult Mouse Cardiac Fibroblast Proliferation and Migration. AT1 Physically Associates With Nox4
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69.
Functional foods might be helpful in improving the nutritional status and preventing certain diseases. In order to inform the consumer about the benefit of a product it will be necessary to enable scientifically proved health claims. These health claims have to be supported by studies and should make clear how a product can influence health. Only if there are proven facts, functional foods could establish on the market as foods of the future in the longer term beside the naturally healthful products. It will be of no use neither to the consumer nor to the food industry to promote these product group with exaggerated promises as a kind of miracle cure which can help against all diseases. The acceptance of the consumer will depend on credible product concepts. Another important precondition for functional foods is that there are absolutely no health risks associated with the consumption of these products. Recommendations regarding fortification and intake of functional foods must consider this aspect. Side effects by excessive doses or imbalances are to be avoided. The consumer should know that the point is not to take as much as possible of potentially healthful single substances but to show clearly that physiological dosages, which can also be attained by a higher intake of traditional food are associated with the best benefit‐risk relation, i.e. show the greatest benefit and minimal risk. In general functional foods do not resolve any nutritional problem. The effects are limited, especially if the nutrition is imbalanced (e.g. hyperenergetic, high fat). In these cases the addition of functional foods offers no or only small corrective effects. Functional foods represent no substitute for a fully balanced nourishment with a high amount of naturally healthy foods such as vegetables, fruits, whole grain products as well as milk and milk products. 相似文献
70.
Maike Lenz Niels Borlinghaus Leonie Weinmann Bettina M. Nestl 《World journal of microbiology & biotechnology》2017,33(11):199
Imine reductases are nicotinamide-dependent enzymes that catalyze the asymmetric reduction of various imines to the corresponding amine products. Owing to the increasing roles of chiral amines and heterocyclic compounds as intermediates for pharmaceuticals, the demand for novel selective synthesis strategies is vitally important. Recent studies have demonstrated the discovery and structural characterization of a number of stereoselective imine reductase enzymes. Here, we highlight recent progress in applying imine reductases for the formation of chiral amines and heterocycles. It particularly focuses on the utilization of imine reductases in reductive aminations of aldehydes and ketones with various amine nucleophiles, one of the most powerful reactions in the synthesis of chiral amines. Second, we report on the synthesis of saturated substituted N-heterocycles by combining them with further biocatalysts, such as carboxylic acid reductases, oxidases or transaminases. Finally, we summarize the latest applications of imine reductases in the promiscuous asymmetric hydrogenation of a highly reactive carbonyl compound and the engineering of the cofactor specificity from NADPH to NADH. 相似文献