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Human B-cell glucokinase displays sigmoidal kinetics towards D-glucose or D-mannose, but fails to do so towards D-fructose. Yet, D-glucose, D-mannose and 2-deoxy-D-glucose confer to the enzyme positive cooperativity towards D-fructose. For instance, in the presence of 5 mM D-[U-14C]fructose, its rate of phosphorylation is increased to 214.3 +/- 11.0%, 134.0 +/- 4.3% and 116.5 +/- 3.0% of paired control value by D-glucose, D-mannose and 2-deoxy-D-glucose (each 6 mM), respectively. D-glucose and, to a lesser extent, D-mannose also display reciprocal kinetic cooperativity. D-fructose, however, fails to affect D-glucose or D-mannose phosphorylation under conditions in which positive cooperativity is otherwise observed. These findings are relevant to the reciprocal effects of distinct hexoses upon their phosphorylation by B-cell glucokinase and, as such, to the metabolic and functional response evoked in pancreatic islet B-cells by these sugars, when tested either separately or in combination.  相似文献   
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Thiosulfate in the form of sodium thiosulfate (STS) is a major oxidation product of hydrogen sulfide (H2S), an endogenous signaling molecule and the third member of the gasotransmitter family. STS is currently used in the clinical treatment of acute cyanide poisoning, cisplatin toxicities in cancer therapy, and calciphylaxis in dialysis patients. Burgeoning evidence show that STS has antioxidant and anti-inflammatory properties, making it a potential therapeutic candidate molecule that can target multiple molecular pathways in various diseases and drug-induced toxicities. This review discusses the biochemical and molecular pathways in the generation of STS from H2S, its clinical usefulness, and potential clinical applications, as well as the molecular mechanisms underlying these clinical applications and a future perspective in kidney transplantation.  相似文献   
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Text-based image retrieval may perform poorly due to the irrelevant and/or incomplete text surrounding the images in the web pages. In such situations, visual content of the images can be leveraged to improve the image ranking performance. In this paper, we look into this problem of image re-ranking and propose a system that automatically constructs multiple candidate “multi-instance bags (MI-bags)”, which are likely to contain relevant images. These automatically constructed bags are then utilized by ensembles of Multiple Instance Learning (MIL) classifiers and the images are re-ranked according to the final classification responses. Our method is unsupervised in the sense that, the only input to the system is the text query itself, without any user feedback or annotation. The experimental results demonstrate that constructing multiple instance bags based on the retrieval order and utilizing ensembles of MIL classifiers greatly enhance the retrieval performance, achieving on par or better results compared to the state-of-the-art.  相似文献   
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Palmitoyl CoA-glycerol-3-phosphate acyltransferase, phosphatidate phosphohydrolase, and phospholipase A were assayed in subcellular fractions of rat lung, including lamellar bodies, the putative site of storage and secretion of lung surfactant. The specific activity of each of these enzymes in lamellar bodies was relatively low and could be entirely accounted for by a small contamination of the lamellar bodies fraction by microsomes, as quantitated by the presence of the microsomal marker reduced triphosphopyridine nucleotide cytochromec reductase. These data indicate that lamellar bodies are not the site of synthesis of the lipid component of pulmonary surfactant by pathways involving these enzymes.  相似文献   
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Little is known about cultural differences in psychological adjustment and perception of illness (PI) during medical procedures in general and radiotherapy in particular. This study compares a Turkish (TP) and a French speaking Belgian (BP) population. A group of 296 consecutive patients attending the radiotherapy clinic of Institut Jules Bordet, Brussels, (n = 172) and Oncology Institute, Capa-Istanbul, (n = 124) were interviewed and assessed by a symptom checklist, the SCL-90-R, at the beginning and at the end of the radiotherapy. PI, derived from a semi-structured interview, was assessed at the beginning of radiotherapy by a five-point observer-rating scale derived from the Omega Vulnerability Rating Scale. Differences in SCL-90-R scores, taking into account country, age, gender, level of education and PI as potential explanatory variables, have been tested by a multivariate analysis of variance with a design of repeated measures using the SCL-90-R scores as dependent variables. Mainly a time effect and a country effect have been found. Some interactions between both effects have also been found. Globally, all the SCL-90-R scores decrease between the beginning and the end of the radiotherapy. The effect of country is noticeable for most of the SCL-90-R components, with higher scores in the BP, except for the positive symptom total score where the TP showed higher scores. The interaction between country and time is not significant, the scores of both the BP and TP decreasing over time, except for somatization scores (P < 0.001) where the scores of the BP were stable over time while the scores of the TP decreased considerably, and for paranoid ideation scores (P = 0.001) where the scores of the BP decreased while the scores of the TP increased. Results showed a higher rate of correct perception in the BP compared to the TP (P = 0.0001). A PI effect has been found for somatization (P = 0.02), anxiety (P = 0.01) and Global Severity Index scores (P = 0.05), with higher mean scores for the "correct perception" category. No interaction with time was found. A significant interaction effect between country and PI has been found for anxiety scores with higher scores in the correct perception category in the BP and in the "denial of implications" category in the TP (P < 0.001). Results highlight cultural differences in psychological adjustment and/or in the responses to self-report questionnaires: greater weight was given to items by the BP, more numerous items were scored by the TP, and greater weight was given to the somatization subscale compared to the psychological subscales by the TP. This study suggests that psychosocial distress is expressed differently in Belgium and Turkey, where patients express mostly somatic complaints. Finally PI, a culture-dependent factor, appears to influence psychological adjustment very differently, a correct perception of illness leading to more anxiety in the BP compared to the TP.  相似文献   
7.
Quality function deployment (QFD) is a systematic process for translating customer needs into engineering characteristics, and then communicating them throughout the enterprise in a way to ensure that details are quantified and controlled. The inherent fuzziness of relationships in QFD modeling justifies the use of fuzzy regression for estimating the relationships between both customer needs and engineering characteristics, and among engineering characteristics. Albeit QFD aims to maximize customer satisfaction, requirements related to enterprise satisfaction such as cost budget, extendibility, and technical difficulty also need to be considered. This paper presents a fuzzy multiple objective decision framework that includes not only fulfillment of engineering characteristics to maximize customer satisfaction, but also maximization of extendibility and minimization of technical difficulty of engineering characteristics as objectives subject to a financial budget constraint to determine target levels of engineering characteristics in product design. A real-world quality improvement problem is presented to illustrate the application of the decision approach.  相似文献   
8.
In sports and board games, when an opponent cheats, the other players typically greet it with disdain, anger, and disengagement. However, work has yet to fully address the role of the computer cheating in video games. In this study, participants played either a cheating or a non-cheating version of a modified open-source tower-defense game. Results indicate that when a computer competitor cheats, players perceive the opponent as being more human. Cheating also increases player aggravation and presence, but does not affect enjoyment of the experience. Additionally, players that firmly believed that their opponent was controlled by the computer exhibited significantly less state hostility compared to players that were less certain of the nature of their competitor. Game designers can integrate subtle levels of cheating into computer opponents without any real negative responses from the players. The results indicate that minor levels of cheating might also increase player engagement with video games.  相似文献   
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Network on chip (NoC) has been proposed as an appropriate solution for today’s on-chip communication challenges. Power dissipation has become a key factor in the NoCs because of their shrinking sizes. In this paper, we propose a new encoding approach aimed at power reduction by decreasing the number of switching activities on the buses. This approach assigns the symbols to data word in such a way that the more frequent words are sent by less power consumption. This algorithm dedicates the symbols with less ones to high probability data and uses transition signaling to transmit data. The proposed method, unlike the existing low power encoding, does not rely on spatial redundancy and keeps the width of the bus constant. Experimental evaluations show that our approach reduces the power dissipation up to 46 % with 2.70, 0.51, and 15.43 % power, critical path and area overhead in the NoCs, respectively.  相似文献   
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