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排序方式: 共有653条查询结果,搜索用时 31 毫秒
1.
Aram Ismail Elizabeth Lewis Birgitta Sjdin Bengt Mannervik 《International journal of molecular sciences》2021,22(8)
Glutathione transferases (GSTs) form a family of detoxication enzymes instrumental in the inactivation and elimination of electrophilic mutagenic and carcinogenic compounds. The Pi class GST P1-1 is present in most tissues and is commonly overexpressed in neoplastic cells. GST P1-1 in the dog, Canis lupus familiaris, has merits as a marker for tumors and as a target for enzyme-activated prodrugs. We produced the canine enzyme CluGST P1-1 by heterologous bacterial expression and verified its cross-reactivity with antihuman-GST P1-1 antibodies. The catalytic activity with alternative substrates of biological significance was determined, and the most active substrate found was benzyl isothiocyanate. Among established GST inhibitors, Cibacron Blue showed positive cooperativity with an IC50 value of 43 nM. Dog GST P1-1 catalyzes activation of the prodrug Telcyta, but the activity is significantly lower than that of the human homolog. 相似文献
2.
Hanna Harrysson Birgitta Swolin Michael Axelsson Ingrid Undeland 《International Journal of Food Science & Technology》2020,55(6):2462-2471
Whole body saline-perfused rainbow trout (Oncorhynchus mykiss) was ice-stored for 4 weeks and compared with unwashed/washed minces from unbled and bled trout in terms of rancid odour, peroxide value (PV), thiobarbituric acid reactive substances (TBARS) and redness loss. Muscle from saline-perfused fish, which had 72% less total haem, was deficient in rancid odour during the whole storage, while bled (54% less haem) and unbled samples developed rancid odour already after ~4 and 2 days; higher intensity without bleeding. PV/TBARS also developed in the order unbled > bled > perfused samples; however, PV/TBARS were not as completely prevented as rancid odour after perfusion. Saline washing (3 × 3 volumes) of unbled mince removed 84% haem and yielded the second most stable sample while saline washing (1 × 1 volumes) destabilised unbled mince, despite 64% haem removal. Concurrent antioxidant removal during washing of minces obviously counteracted the effect of blood removal and washing fish mince with small volumes of solution should be used with great care. 相似文献
3.
Glenn P. Svensson Eylem Akman Gündüz Natalia Sjöberg Erik Hedenström Jean-Marc Lassance Hong-Lei Wang Christer Löfstedt Olle Anderbrant 《Journal of chemical ecology》2014,40(4):387-395
The greater wax moth, Galleria mellonella (L.), is a serious and widespread pest of the honeybee, Apis mellifera L. In contrast to most moths, for which long-range mate finding is mediated by female-produced sex pheromones, G. mellonella males attract conspecific females over long distances by emitting large amounts of a characteristic scent in combination with bursts of ultrasonic calls. The male scent for this species was previously identified as a blend of nonanal and undecanal. When these compounds were bioassayed, characteristic short-range sexual behavior, including wing fanning, was triggered in conspecific females, but the aldehyde blend failed to elicit attraction over longer distances. We identified, via analysis and synthesis, a third male-specific compound, 5,11-dimethylpentacosane. We show that it acts as a behavioral synergist to the aldehydes. In wind tunnel experiments, very few female moths responded to the aldehyde blend or to 5,11-dimethylpentacosane tested separately, but consistently showed orientation and source contact when a combination of all three compounds was applied. The level of attraction to the three-component mixture was still lower than that to male extract, indicating that the composition of compounds in the synthetic blend is suboptimal, or that additional pheromone components of G. mellonella are yet to be identified. The identification of 5,11-dimethylpentacosane is an important step for the development of an efficient long-range attractant that will be integrated with other environmentally safe strategies to reduce damage to beehives caused by wax moths. 相似文献
4.
This study outlined the influence of a number of parameters affecting the emission rate from one of the largest sources of VOC in the building stock in the Nordic countries. This source is flooring systems of polyvinyl chloride or linoleum attached to a substrate of moisture damaged or insufficiently dried concrete. The secondary emission rate of degradation products was measured, with the Field and Laboratory Emission Cell, on different flooring systems consisting of three different floorings and three adhesives, exposed to three different aqueous solutions in the range of 11-13.1 pH. The conclusion drawn in this study is that the great majority of the secondary emission originates from the floor adhesive. The occurrence of adhesive and the amount of adhesive used have a significant influence on the emission rate. A critical pH value for degradation of the adhesive seems to lie somewhere between 11 and 13 pH. PRACTICAL IMPLICATIONS: When designing a floor system or a renovation of a damaged flooring system, it is important to bear in mind the influence of parameters that may drastically shorten the service life. Flooring adhesive may decompose in a moist alkaline environment and give rise to unacceptable secondary emission rates. 相似文献
5.
ABSTRACT This paper describes the formation of the planning issue ‘Nordic Superblock’ through the early planning phase of the Hiedanranta area in Tampere, Finland. The workshops with citizens and professionals as participants, held after a planning competition, were an important part of the area’s initial planning. The paper argues that the superblock issue emerged because the institutional context differed from the traditional zoning process. Furthermore, the issue itself challenged the traditional planning process and the current urban development regime. The case is a promising example of the outcome of expert–citizen interaction; however, it also reveals some bottlenecks in the planning process. 相似文献
6.
7.
Constantin Mihai Gabriel Ştefan Liviu-Daniel Ionescu Bogdan Duong Ngoc Q. K. Demarty Claire-Héléne Sjöberg Mats 《International Journal of Computer Vision》2021,129(5):1526-1550
International Journal of Computer Vision - In this paper, we report on the creation of a publicly available, common evaluation framework for image and video visual interestingness prediction. We... 相似文献
8.
J. H. Sjølund D. Peeters E. Lund 《Structural and Multidisciplinary Optimization》2018,58(5):1885-1897
In this work, a new thickness parameterization which allows for internal ply-drops without intermediate voids is introduced in the Discrete Material and Thickness Optimization (DMTO) method. With the original DMTO formulation, material had to be removed from the top in order to prevent non-physical intermediate voids in the structure. The new thickness formulation relies on a relation between density variables and ply-thicknesses rather than constitutive properties. This new formulation allows internal ply-drops which is essential for composite structures as it is common practice to cover dropped plies as to avoid delaminations. Furthermore, it is demonstrated how the new thickness formulation in some cases improves the convergence characteristics. Finally, it is also shown how solid-shell elements can be utilized within the DMTO method for structural optimization of tapered laminated composite structures. 相似文献
9.
Anna Runnemalm Jörgen Ahlberg Anders Appelgren Stefan Sjökvist 《Journal of Nondestructive Evaluation》2014,33(3):398-406
The interest for thermography as a method for spot weld inspection has increased during the last years since it is a full-field method suitable for automatic inspection. Thermography systems can be developed in different ways, with different physical setups, excitation sources, and image analysis algorithms. In this paper we suggest a single-sided setup of a thermography system using a flash lamp as excitation source. The analysis algorithm aims to find the spatial region in the acquired images corresponding to the successfully welded area, i.e., the nugget size. Experiments show that the system is able to detect spot welds, measure the nugget diameter, and based on the information also separate a spot weld from a stick weld. The system is capable to inspect more than four spot welds per minute, and has potential for an automatic non-destructive system for spot weld inspection. The development opportunities are significant, since the algorithm used in the initial analysis is rather simplified. Moreover, further evaluation of alternative excitation sources can potentially improve the performance. 相似文献
10.
Zandra Arwidsson Kristin Elgh-Dalgren Thomas von Kronhelm Ragnar Sjöberg Bert Allard Patrick van Hees 《Journal of hazardous materials》2010,173(1-3):697-704
Removal of Cu, Pb, and Zn by the action of the two biodegradable chelating agents [S,S]-ethylenediaminedisuccinic acid (EDDS) and methylglycinediacetic acid (MGDA), as well as citric acid, was tested. Three soil samples, which had previously been treated by conventional soil washing (water), were utilized in the leaching tests. Experiments were performed in batches (0.3 kg-scale) and with a WTC-mixer system (Water Treatment Construction, 10 kg-scale). EDDS and MGDA were most often equally efficient in removing Cu, Pb, and Zn after 10–60 min. Nonetheless, after 10 d, there were occasionally significant differences in extraction efficiencies. Extraction with citric acid was generally less efficient, however equal for Zn (mainly) after 10 d. Metal removal was similar in batch and WTC-mixer systems, which indicates that a dynamic mixer system could be used in full-scale. Use of biodegradable amino polycarboxylic acids for metal removal, as a second step after soil washing, would release most remaining metals (Cu, Pb and Zn) from the present soils, however only after long leaching time. Thus, a full-scale procedure, based on enhanced metal leaching by amino polycarboxylic acids from soil of the present kind, would require a pre-leaching step lasting several days in order to be efficient. 相似文献