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排序方式: 共有326条查询结果,搜索用时 15 毫秒
81.
Blanc F Vissers YM Adel-Patient K Rigby NM Mackie AR Gunning AP Wellner NK Skov PS Przybylski-Nicaise L Ballmer-Weber B Zuidmeer-Jongejan L Szépfalusi Z Ruinemans-Koerts J Jansen AP Bernard H Wal JM Savelkoul HF Wichers HJ Mills EN 《Molecular nutrition & food research》2011,55(12):1887-1894
Scope : Roasting rather than boiling and Maillard modifications may modulate peanut allergenicity. We investigated how these factors affect the allergenic properties of a major peanut allergen, Ara h 1. Methods and results : Ara h 1 was purified from either raw (N‐Ara h 1) or roasted (R‐Ara h 1) peanuts. Boiling (100°C 15 min; H‐Ara h 1) resulted in a partial loss of Ara h 1 secondary structure and formation of rod‐like branched aggregates with reduced IgE‐binding capacity and impaired ability to induce mediator release. Glycated Ara h 1 (G‐Ara h 1) formed by boiling in the presence of glucose behaved similarly. However, H‐ and G‐Ara h1 retained the T‐cell reactivity of N‐Ara h 1. R‐Ara h 1 was denatured, comprised compact, globular aggregates, and showed no evidence of glycation but retained the IgE‐binding capacity of the native protein. Conclusion : Ara h 1 aggregates formed by boiling were morphologically distinct from those formed by roasting and had lower allergenic activity. Glycation had no additional effect on Ara h 1 allergenicity compared with heating alone. Taken together with published data on the loss of Ara h 2/6 from boiled peanuts, this supports the hypothesis that boiling reduces the allergenicity of peanuts. 相似文献
82.
83.
Specht A Thomann JS Alarcon K Wittayanan W Ogden D Furuta T Kurakawa Y Goeldner M 《Chembiochem : a European journal of chemical biology》2006,7(11):1690-1695
We report here the syntheses and the photolytic properties of 3-(4,5-dimethoxy-2-nitrophenyl)-2-butyl (DMNPB) esters as new photoremovable groups for carboxylic acids, and their use for the caging of L-glutamate. A high-yielding synthesis of the DMNPB esters led to a 4:1 threo/erythro diastereomeric mixture, which could be separated by HPLC. While these esters were stable in neutral buffer, photolysis at 364 nm induced a > or =95 % release of the carboxylic acid, with a 0.26 quantum yield for L-glutamate formation. L-Glutamate release was also possible by two-photon photolysis with an action cross section of 0.17 GM at 720 nm. Laser photolysis at 350 nm generated a transient species at around 410 nm, attributed to a quinonoid aci-nitro intermediate that decayed in the submillisecond time range (t(1/2)=0.53 ms) for the faster gamma-L-glutamyl threo-esters. Given the absorbance of these esters (lambda(max)=350 nm; epsilon=4500), the threo DMNPB esters represent new caging groups that can be efficiently photolyzed at near-UV wavelengths. An efficient and rapid photolytic release of L-glutamate has been demonstrated on hippocampal neurons in primary culture. 相似文献
84.
Valérie Loizeau Hanan Tanouti Audrie Marcheguet Guillaume Loubière Philippe Aegerter Hocine Drioueche Sandra Pembebjoglou 《Hemodialysis international. International Symposium on Home Hemodialysis》2023,27(4):364-369
Background
There are two techniques for puncturing an arteriovenous fistula: one where the needle is inserted bevel up and then rotated to a bevel down position, and another where the needle is inserted bevel down. The aim of this study was to compare these two methods of needle insertion on minimum compression time required for hemostasis after needle removal.Methods
This was a prospective, randomized, cross-over, blinded, single-center, routine care study. Each patient's average post-dialysis puncture site compression time was determined during a 2-week baseline period while using bevel-up access puncture. Subsequently, minimum post-dialysis puncture-site compression time was determined during each of two sequential follow-up periods, during which fistula puncture was done with needles inserted bevel up or down, respectively. The order of treatments (bevel up or bevel down insertion) was randomized. During each follow-up period, the minimum compression time necessary to avoid bleeding on needle removal was determined by progressively shortening the compression time. Puncture-associated pain was also assessed as prepump and venous pressures and ability to achieve desired blood flow rate during the dialysis session.Results
Forty-two patients were recruited. The baseline compression time after needle removal averaged 9.99 ± 2.7 min During the intervention periods, the minimum compression time was on average 10.8 min (9.23–12.4) when the access needles had been inserted bevel down versus 11.1 min (9.61–12.5) when the access needles had been inserted bevel up (p = 0.72). There was no difference in puncture-associated pain between the two insertion techniques, and no difference in prepump or venous pressures or ability to achieve the desired blood flow rate during the dialysis session.Conclusion
Bevel-up and bevel-down needle orientation during arteriovenous fistula puncture are equivalent techniques in terms of achieving hemostasis on needle removal, and puncture-associated pain. 相似文献85.
86.
Canalle Gabrielle Karine Salgado Ana Carolina Loscio Bernadette Farias 《Journal of Intelligent Information Systems》2021,57(1):25-50
Journal of Intelligent Information Systems - Data fusion is the process of merging records from multiple sources which represent the same real-world object into a single representation. This review... 相似文献
87.
The electrochemical reduction of flavin adenine dinucleotide (FAD) is studied in a classical electrochemical cell as well as in two types of microreactors: the first one is a one-channel reactor and the other one, a multichannel filter-press reactor. The ultimate goal is to use the reduced form of flavin (FADH2), in the presence of formate dehydrogenase (FDH), in order to continuously regenerate the reduced form of nicotinamide adenine dinucleotide (NADH) for chiral syntheses. Various voltammetric and adsorption measurements were carried out for a better understanding of the redox behavior of the FAD as well as its adsorption on gold. Diffusivity and kinetic electrochemical parameters of FAD were determined. 相似文献
88.
89.
Rafaelle Gomes Santiago Bianca Ferreira dos Santos Isabela Gomes Lima Karine Oliveira Moura Dárley Carrijo Melo Wilson Mantovani Grava 《Chemical Engineering Communications》2019,206(11):1367-1374
AbstractThe presence of humidity in gas streams is usually associated to several problems in the performance of industrial unit operations. Therefore, gas drying is one of the most important primary stages in the process that is commonly carried out by adsorption, using hydrophilic porous materials. These materials are typically regenerated by temperature swings (TSA), which in the presence of contaminants in the gas stream, may lead to adsorbent degradation and reduced lifespan of the drying process. The objective of this study is to investigate the hydrothermal stability of a zeolitic material used in the process of natural gas drying, by means of an aging test developed to simulate the operating conditions of a typical TSA. The textural characteristics, elemental analysis, and H2O/CO2 adsorption capacity are determined along the heating/cooling cycles. The presence of hydrocarbons, represented by n-heptane, is the most significant factor that contributed to the aging of the adsorbent within the temperature and pressure ranges under study. 相似文献
90.
Manoela Klüppel Riekes Monika Piazzon Tagliari Andrea Granada Gislaine Kuminek Marcos Antonio Segatto Silva Hellen Karine Stulzer 《Materials science & engineering. C, Materials for biological applications》2010,30(7):1008-1013
The aim of this work was to investigate the inclusion complexation between amiodarone (AMD), a practically water insoluble anti arrhythmic agent, and β-cyclodextrin (βCD) in order to improve the solubility and the dissolution rate of the drug, in an attempt to enhance its bioavailability. The complexation was done through different methods: physical mixture (PM), coevaporated (CV), freeze-drying (FD) and spray-drying (SD). The data analysis indicated that the complexes produced by freeze-drying and spray-drying techniques resulted in amorphous samples (data obtained by DSC and XRPD), and showed a possible chemical interaction between OH-βCD group and AMD tertiary amine (visualized by FT-IR). Also, they presented higher thermal stability (demonstrated by TG) and the improvement of the drug dissolution rate. 相似文献