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排序方式: 共有249条查询结果,搜索用时 15 毫秒
241.
Hedenström E Edlund H Wassgren AB Bergström G Anderbrant O Ostrand F Sierpinski A Auger-Rozenberg MA Herz A Heitland W Varama M 《Journal of chemical ecology》2006,32(11):2525-2541
We present the identification of the sex pheromone in the pine sawfly, Gilpinia pallida, including analysis of the female pheromone content, male antennal response and attraction in the field, and synthesis of the most active pheromone component. Several 3,7-dimethyl-2-alkanols were identified from female whole-body extracts, including some compounds with a 2R configuration. This is the first observation of such compounds in a pine sawfly species. Antennae of male G. pallida responded strongly in electroantennograph (EAG) recordings to the (2S,3R,7R)-isomers of the propionates of 3,7-dimethyl-2-tridecanol, 3,7-dimethyl-2-tetradecanol, and 3,7-dimethyl-2-pentadecanol, as well as to the acetates of the tri- and pentadecanols (the acetate of the tetradecanol was not tested). The propionate of (2S,3R,7R)-3,7-dimethyl-2-tetradecanol caught more males in the field than the corresponding isomer of tri- or pentadecanol. We suggest that the (2S,3R,7R)-isomer of 3,7-dimethyl-2-tetradecanol is likely the main sex pheromone precursor in G. pallida, with a subsidiary role for the (2S,3R,7R)-isomer of the tridecanol. Preparation of highly pure (2R,3R,7R)- and (2S,3R,7R)-stereoisomers of 3,7-dimethyl-2-tetradecanol, including the biological active esters, was performed via chemoenzymatic methods and is described in detail. 相似文献
242.
Food allergy is an important issue in the field of food safety because of the hazards for affected persons and the hygiene requirements and legal regulations imposed on the food industry. Consumer protection and law enforcement require suitable analytical techniques for the detection of allergens in foods. Immunological methods are currently preferred; however, confirmatory alternatives are needed. The determination of allergenic proteins by liquid chromatography and mass spectrometry has greatly advanced in recent years, and gel-free allergenomics is becoming a routinely used approach for the identification and quantitation of food allergens. The present review provides a brief overview of the principles of proteomic procedures, various chromatographic set ups, and mass spectrometry instrumentation used in allergenomics. A compendium of published liquid chromatography methods, proteomic analyses, typical marker peptides, and quantitative assays for 14 main allergy-causing foods is also included. 相似文献
243.
Nadine Ansorge Christian Dannecker Udo Jeschke Elisa Schmoeckel Helene Hildegard Heidegger Aurelia Vattai Maximiliane Burgmann Bastian Czogalla Sven Mahner Sophie Fuerst 《International journal of molecular sciences》2022,23(9)
Vulvar cancer incidence numbers have been steadily rising over the past decades. In particular, the number of young patients with vulvar cancer has recently increased. Therefore, the need to identify new prognostic factors and, in addition, therapeutic options for vulvar carcinoma is more apparent. The aim of this study was to analyze the influx of COX-2 positive tumor-infiltrating lymphocytes and monocytes and their influence on prognosis. Using subtyping by immunofluorescence, the majority of COX-2 expressing immune cells were identified as FOXP3-positive regulatory T cells. In addition, peri- and intra-tumoral macrophages in the same tumor tissue were detected simultaneously as M2-polarized macrophages. COX-2 positive immune cells were independent negative prognostic markers in long-term overall survival of patients with vulvar cancer. These results show an influence of immune cell infiltration for vulvar carcinoma patients. Immune cell infiltration and immune checkpoint expression may, therefore, become interesting targets for further research on new vulvar cancer treatment strategies. 相似文献
244.
Michelle Dai Winnie Xu Helene Chesnais Nancy Anabaraonye James Parente Shampa Chatterjee Chamith S. Rajapakse 《International journal of molecular sciences》2022,23(21)
A major pathophysiological cause of cardiovascular disease is vascular plaque calcification. Fluorine 18–Sodium Fluoride (18F-NaF) PET/CT can be used as a sensitive imaging modality for detection of vascular calcification. The aim of this study was to find a non-invasive, cost-efficient, and readily available metric for predicting vascular calcification severity. This retrospective study was performed on 36 participants who underwent 18F-NaF fused PET/CT scans. The mean standard uptake values (SUVs) were calculated from manually sectioned axial sections over the aortic arch and thoracic aorta. Correlation analyses were performed between SUVs and calculated atherogenic indices (AIs). Castelli’s Risk Index I (r = 0.63, p < 0.0001), Castelli’s Risk Index II (r = 0.64, p < 0.0001), Atherogenic Coefficient (r = 0.63, p < 0.0001), Atherogenic Index of Plasma (r = 0.51, p = 0.00152), and standalone high-density lipoprotein (HDL) cholesterol (r = −0.53, p = 0.000786) were associated with aortic calcification. AIs show strong association with aortic arch and thoracic aorta calcifications. AIs are better predictors of vascular calcification compared to standalone lipid metrics, with the exception of HDL cholesterol. Clinical application of AIs provides a holistic metric beneficial for enhancing screening and treatment protocols. 相似文献
245.
Ohne Zusammenfassung 相似文献
246.
247.
Ouwen Zhai Helene Baust Dr.-Ing. Marco Gleiß Prof. Dr.-Ing. Hermann Nirschl 《化学,工程师,技术》2023,95(1-2):189-198
The scale up of solid bowl centrifuges is a major challenge as the process and material behavior are complex and difficult to describe. A common approach to forecast the process behavior is to use analytical models and transfer the experience gained from the lab to the industrial scale. In this context, time-consuming and cost-intensive pilot scale experiments are necessary. This paper presents a methodology to improve the scale up process and make it more sustainable by using a numerical model that allows the real-time tracking of the process and a more reliable scale up process. For this approach, the material behavior is derived from laboratory experiments whereby the scalability is given. Here, the determination of material functions allows an accurate representation of the material behavior for solid bowl centrifuges of different scales. The focus of this paper is the detailed explanation of material related functions for the scale up of decanter centrifuges. 相似文献
248.
Raghuraj Hoshing Dr. Blaise W. Leeber III Dr. Helene Kuhn Dr. David Caianiello Brandon Dale Michael Saladino Robert Lusi Natalie Palaychuk Sarah Weingarten Prof. Amit Basu 《Chembiochem : a European journal of chemical biology》2022,23(6):e202100532
Yariv reagents are glycosylated triphenylazo dyes that bind to arabinogalactan proteins (AGPs), proteoglycans found in plant cell walls that are integral for plant growth and development. Yariv reagents are widely utilized as imaging, purification, and quantification tools for AGPs and represent the only small molecule probe for interrogating AGP function. The ability of Yariv reagents to bind to AGPs is dependent on the structure of the terminal glycoside on the dye. The reason for this selectivity has not been understood until the present work. Using circular dichroism spectroscopy, we show that the Yariv reagents form supramolecular aggregates with helical chirality. More significantly, the ability of the Yariv reagent to bind AGPs is correlated with this helical chirality. This finding paves the way towards developing a more detailed understanding of the nature of the Yariv-AGP complex, and the design of AGP-binding reagents with higher affinities and selectivities. 相似文献
249.
Katharina Henn Helene Christine Reinbach Søren Bøye Olsen Margit Dall Aaslyng Susanne Margarete Bølling Laugesen Wender L. P. Bredie 《Journal of food science》2023,88(3):1144-1158
Despite the known health benefits and the potential for substituting less environmentally sustainable consumed foods such as meat, the current intake of pulses in developed countries remains less than recommended. Barriers are related to sensory characteristics and lack of knowledge about preparation, while drivers of environmental benefits are intangible. The aim of this study was to investigate the effect of additional information about health or environmental benefits of pulses on the acceptance of novel pulse-based products from chickpeas, black beans, and faba beans. Perceptions of these pulse-based spreads in a blind and informed stage were assessed with 202 consumers in urban and suburban areas of Denmark. In general, the familiar chickpea spread followed by the relatively most unfamiliar black bean spread was liked the most. Only for these two products, additional information increased hedonic perception, regardless of the context (health or environmental benefits). If consumers did not like the spread, as found for the faba bean spread, providing additional information did not significantly alter this perception. Participants’ preferences and willingness to pay (WTP) in a discrete choice experiment corresponded to hedonic scores, whereas providing additional information increased the WTP. These findings suggest that extrinsic cues such as health or environmental benefits may only be useful in products with an acceptable baseline taste profile. Moreover, black beans might be investigated as a promising source for further product development due to their acceptance by consumers besides being the comparably most unfamiliar pulse type. 相似文献