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排序方式: 共有1614条查询结果,搜索用时 34 毫秒
971.
Caroline de Souza Pereira Helenita Costa Quadros Dr. Diogo Rodrigo Magalhaes Moreira Dr. William Castro Romulo Ivisson Santos De Deus Da Silva Dr. Milena Botelho Pereira Soares Dr. Diana Fontinha Dr. Miguel Prudêncio Vinicius Schmitz Prof. Hélio F. Dos Santos Mathieu Gendrot Isabelle Fonta Joel Mosnier Dr. Bruno Pradines Prof. Maribel Navarro 《ChemMedChem》2021,16(4):662-678
Plasmodium parasites kill 435 000 people around the world every year due to unavailable vaccines, a limited arsenal of antimalarial drugs, delayed treatment, and the reduced clinical effectiveness of current practices caused by drug resistance. Therefore, there is an urgent need to discover and develop new antiplasmodial candidates. In this work, we present a novel strategy to develop a multitarget metallic hybrid antimalarial agent with possible dual efficacy in both sexual and asexual erythrocytic stages. A hybrid of antimalarial drugs (chloroquine and primaquine) linked by gold(I) was synthesized and characterized by spectroscopic and analytical techniques. The CQPQ-gold(I) hybrid molecule affects essential parasite targets, it inhibits β-hematin formation and interacts moderately with the DNA minor groove. Its interaction with PfTrxR was also examined in computational modeling studies. The CQPQ-gold(I) hybrid displayed an excellent in vitro antimalarial activity against the blood-stage of Plasmodium falciparum and liver-stage of Plasmodium berghei and efficacy in vivo against P. berghei, thereby demonstrating its multiple-stage antiplasmodial activity. This metallic hybrid is a promising chemotherapeutic agent that could act in the treatment, prevention, and transmission of malaria. 相似文献
972.
Diana Rocha-Mendoza Erica Kosmerl Abigail Krentz Lin Zhang Shivani Badiger Gonzalo Miyagusuku-Cruzado Alba Mayta-Apaza Monica Giusti Rafael Jiménez-Flores Israel García-Cano 《Journal of dairy science》2021,104(2):1262-1275
In recent years, acid whey production has increased due to a growing demand for Greek yogurt and acid-coagulated cheeses. Acid whey is a dairy by-product for which the industry has long struggled to find a sustainable application. Bulk amounts of acid whey associated with the dairy industry have led to increasing research on ways to valorize it. Industry players are finding ways to use acid whey on-site with ultrafiltration techniques and biodigesters, to reduce transportation costs and provide energy for the facility. Academia has sought to further investigate practical uses and benefits of this by-product. Although modern research has shown many other possible applications for acid whey, no comprehensive review yet exists about its composition, utilization, and health benefits. In this review, the industrial trends, the applications and uses, and the potential health benefits associated with the consumption of acid whey are discussed. The proximal composition of acid whey is discussed in depth. In addition, the potential applications of acid whey, such as its use as a starting material in the production of fermented beverages, as growth medium for cultivation of lactic acid bacteria in replacement of commercial media, and as a substrate for the isolation of lactose and minerals, are reviewed. Finally, the potential health benefits of the major protein constituents of acid whey, bioactive phospholipids, and organic acids such as lactic acid are described. Acid whey has promising applications related to potential health benefits, ranging from antibacterial effects to cognitive development for babies to human gut health. 相似文献
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976.
Maynard Diana Lepori Benedetto Petrak Johann Song Xingyi Laredo Philippe 《Scientometrics》2020,125(2):1275-1290
Scientometrics - Understanding knowledge co-creation in key emerging areas of European research is critical for policy makers wishing to analyze impact and make strategic decisions. However, purely... 相似文献
977.
ABSTRACTThe lack of diversity in engineering and perpetuation of inequities through engineering designs have motivated the rise of new curricula centred on the integration of traditional technical content with social aspects of technology. However, the ‘revolutionizing’ of curricula has primarily been spearheaded by junior faculty, women and faculty of colour. This article uses an autoethnographic approach to explore the development of social justice-oriented curricula within engineering from the perspectives of junior women and faculty of colour. Drawing on feminist and critical race theory, we discuss how power dynamics within the school, university and engineering more broadly have shaped the development and teaching of justice-oriented engineering. Through the lens of our experiences, we show that, despite the support from some institutional allies and administrators, stereotypes, hegemonic norms and microaggressions can undermine efforts for social and structural change in engineering education, even as such changes are supported and promoted by the institution. 相似文献
978.
Cosmin M. Cotrut Alina Vladescu Mihaela Dinu Diana M. Vranceanu 《Ceramics International》2018,44(1):669-677
Surface functionalization of pure titanium (cp-Ti) with hydroxyapatite (HAp) was successfully achieved by means of electrochemical deposition (ED) in a solution containing calcium nitrate and ammonium dihydrogen phosphate. The aim of this study is to evaluate the influence of the deposition temperature on the elemental and phase composition, chemical bonds, morphology, and in vitro electrochemical behaviour in biological simulated media (simulated body fluid - SBF). The roughness and wettability of the developed coatings are also investigated. By increasing the deposition temperature from 50 °C to 75 °C, the HAp coatings present a well-crystalized structure, denser and a nobler behaviour in terms of electrochemical behaviour in SBF at 37 °C. Also, by increasing the deposition temperature from 50 °C to 75 °C, the contact angle has decreased from 76.1° to 27.4°, exhibiting a highly hydrophilic surface. Taking into consideration all the obtained data, electrodeposition of HAp at 75 °C was found preferable when compared to 50 °C. The characteristics of the HAp coatings can be easily adjusted by optimizing the electrochemical deposition parameters and/or controlling specific features like pH, temperature, or ionic concentration of electrolyte, etc. 相似文献
979.
Mara L. Polo Marisa E. Spontón Alfredo Huespe Diana A. Estenoz Gregorio R. Meira 《应用聚合物科学杂志》2021,138(5):49782
In the first article of this sequel (J. Appl. Polym. Sci., 2018, 135, 45747), an experimental and theoretical investigation was developed on the two-steps synthesis of linear segmented thermoplastic polyurethanes. The reactions were carried out at 60°C, with methylene diphenyl diisocyanate (MDI), two poly(tetramethylene oxide) macrodiols, and 1,4-butanediol (BD) as chain extender. In our second article (J. Appl. Polym. Sci., 2019, 136, 46946), a mathematical model for the prepolymerization was developed, that involved integrating a differential equation for each generated polymer species. The present article extends such model, and predicts the molecular structure along the finishing stage. In each stage, the new model first solves the molar balances at polymer topologies level (i.e.,: Disregarding the molar mass distribution [MMD] of the reacted macrodiol chains), and then calculates the MMD of the evolving polymer and its main subsets through an algebraic convolution procedure. The model reproduces the prepolymerization predictions of our previous article, but is three orders of magnitude faster. In the finishing stage, up to 156,000 polymer topologies and 4.53 × 108 polymer species were calculated; and the rate constant was readjusted to (k2 = 0.00129 L mol−1 s−1), in order to fit the measured MMDs. 相似文献
980.
Basu N Abare M Buchanan S Cryderman D Nam DH Sirkin S Schmitt S Hu H 《The Science of the total environment》2010,409(1):70-77
In August 2009 a combined epidemiological and ecological pilot study was conducted to investigate allegations of human rights abuses in the form of exposures to toxic metals experienced by mine workers and Indigenous Mam Mayan near the Marlin Mine in Guatemala. In the human study there were no differences in blood and urine metals when comparing five mine workers with eighteen non-mine workers, and there were no discernible relationships between metal exposures and self-reported health measures in any study group. On the other hand, individuals residing closest to the mine had significantly higher levels of certain metals (urinary mercury, copper, arsenic, and zinc) when compared to those living further away. The levels of blood aluminum, manganese, and cobalt were elevated in comparison to established normal ranges in many individuals; however, there was no apparent relationship to proximity to the mine or occupation, and thus are of unclear significance. In the ecological study, several metals (aluminum, manganese, and cobalt) were found significantly elevated in the river water and sediment sites directly below the mine when compared to sites elsewhere. When the human and ecological results are combined, they suggest that exposures to certain metals may be elevated in sites near the mine but it is not clear if the current magnitude of these elevations poses a significant threat to health. The authors conclude that more robust studies are needed while parallel efforts to minimize the ecological and human impacts of mining proceed. This is critical particularly as the impact of the exposures found could be greatly magnified by expected increases in mining activity over time, synergistic toxicity between metals, and susceptibility for the young and those with pre-existing disease. 相似文献