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941.
Silvia C. Capelli Hans‐Beat Bürgi Sax A. Mason Dylan Jayatilaka 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(10):949-952
Neutron diffraction data have been collected at 12, 50, 150 and 295 K for the dipeptide glycyl‐L‐alanine, C5H10N2O3, in order to obtain accurate positional and anisotropic displacement parameters for the H atoms. The values of these parameters serve as a benchmark for assessing the equivalent parameters obtained from a so‐called Hirshfeld‐atom refinement of X‐ray diffraction data described elsewhere [Capelli et al. (2014). IUCrJ, 1 , 361–379]. The flexibility of the glycyl‐L‐alanine molecule in the solid and the hydrogen‐bonding interactions as a function of temperature are also considered. 相似文献
942.
Jesús Martínez-Solís Fernando Calzada Elizabeth Barbosa Miguel Valds 《Molecules (Basel, Switzerland)》2021,26(9)
The antihyperglycemic and antilipidemic effects of the tea infusion extracts of leaves from Annona cherimola Miller (IELAc-0.5, IELAc-1.5, and IELAc-3.0) were evaluated on normoglycemic (NG) and streptozocin-induced diabetic (STID) mice. In the acute test, IELAc-1.5 at 300 mg/kg bodyweight (bw) exhibited antihyperglycemic activity on STID mice since the first hour of treatment. Then, its antidiabetic potential was analyzed in a subchronic evaluation. IELAc-1.5 was able to reduce the blood glucose level, glycated hemoglobin (HbA1c), cholesterol (CHO), and triglycerides (TG); high-density lipoprotein (HDL) showed an increase at the end of treatment. IELAc-1.5 did not modify the urine profile at the end of the evaluation, and neither toxicity nor macroscopic organ damage were observed in acute and subchronic assays. In addition, a major flavonol glycoside present in the tea infusion extracts was identified using high-performance liquid chromatography with diode array detection (HPLC-DAD). The analysis of the tea infusion extracts by HPLC revealed that rutin was the major component. This study supports the use of tea infusions from Annona cherimola for the treatment of diabetes and suggests that rutin could be responsible, at least in part, for their antidiabetic properties. 相似文献
943.
Numerical Algorithms - Continuous representations are fundamental for modeling sampled data and performing computations and numerical simulations directly on the model or its elements. To... 相似文献
944.
Gabriela Islas M. Elena Páez-Hernández Silvia Corona-Avendaño Alberto Rojas-Hernández Enrique Barrado 《液相色谱法及相关技术杂志》2016,39(14):658-665
A new method based on the combination of dispersive solid-phase extraction and capillary electrophoresis is proposed for the determination of sulfamethoxazole in milk samples. Butylamide silica was synthesized and used as extractant. Factors involved in sample treatment method such as: butylamide silica amount, NaOH concentration in methanol, sample volume, and dispersion time were evaluated using a Taguchi parameter design. Under optimal conditions, average recoveries ranged from 73 to 85% with a limit of detection of 0.05?mg?L?1 were achieved. The proposed method is a useful technique for cleanup milk samples. 相似文献
945.
Exploiting Free‐Energy Minima to Design Novel EphA2 Protein–Protein Antagonists: From Simulation to Experiment and Return 下载免费PDF全文
Dr. Matteo Incerti Dr. Daniele Pala Dr. Carmine Giorgio Dr. Jlenia Brunetti Prof. Luisa Bracci Prof. Paola Vicini Prof. Elisabetta Barocelli Dr. Luigi Capoferri Prof. Silvia Rivara Prof. Massimiliano Tognolini Prof. Marco Mor Prof. Alessio Lodola 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(24):8048-8052
The free‐energy surface (FES) of protein–ligand binding contains information useful for drug design. Here we show how to exploit a free‐energy minimum of a protein‐ligand complex identified by metadynamics simulations to design a new EphA2 antagonist with improved inhibitory potency. 相似文献
946.
Marianne Smits Yun Ling Prof. Dr. Silvia Lenaerts Prof. Dr. Sabine Van Doorslaer 《Chemphyschem》2012,13(18):4251-4257
Photocatalytic soot oxidation is studied on P25 TiO2 as an important model reaction for self‐cleaning processes by means of electron paramagnetic resonance (EPR) and Fourier transform infrared (FTIR) spectroscopy. Contacting of carbon black with P25 leads on the one hand to a reduction of the local dioxygen concentration in the powder. On the other hand, the weakly adsorbed radicals on the carbon particles are likely to act as alternative traps for the photogenerated conduction‐band electrons. We find furthermore that the presence of dioxygen and oxygen‐related radicals is vital for the photocatalytic soot degradation. The complete oxidation of soot to CO2 is evidenced by in situ FTIR spectroscopy, no intermediate CO is detected during the photocatalytic process. 相似文献
947.
Santos Kleilton Oliveira Barbosa Rossemberg Cardoso da Silva Buriti Josué Bezerra Junior André Gonçalves de Sousa Wladymyr Jefferson Bacalhau de Barros Sandra Maria Carvalho de Oliveira Rodrigo José Fook Marcus Vinícius Lia 《Journal of Thermal Analysis and Calorimetry》2019,136(2):725-735
Journal of Thermal Analysis and Calorimetry - The objective of this work was to develop chitosan films incorporated with the eggshell membrane powder (MCO) by the solvent evaporation method with... 相似文献
948.
Rita Traversi Silvia Becagli Emiliano Castellano Ombretta Largiuni Alessio Migliori Mirko Severi 《International journal of environmental analytical chemistry》2013,93(6-7):457-470
The chemical analysis of shallow firn cores sampled in coastal and plateau areas in Northern Victoria Land and along a transect from Talos Dome to Dome C (East Antarctica, Pacific Ocean sector) allowed a global view of spatial and temporal changes in chemical composition of snow depositions over the last 100 years. Variations in concentration of primary (sea spray) and secondary (biogenic emission, atmospheric inputs) source markers were observed and discussed as a function of distance from the sea and altitude. In the stations characterized by relatively high snow accumulation rates, the sub-sampling resolution was sufficient to obtain a stratigraphic dating by using the periodical variations of seasonal markers. In these stations, a subdivision in “summer” and “winter” samples was carried out in order to study the seasonal changes of the contributions of the measured compounds to the snow composition as elevation and distance from the sea increase. Some evidence of post-depositional effects which are able to change the original deposition of chloride and nitrate, was observed at stations with low accumulation rates. The reliability of the depth/concentration profile of these substances for reconstructing past deposition was also discussed. 相似文献
949.
950.
Tumour‐Targeted Drug Delivery with Mannose‐Functionalized Nanoparticles Self‐Assembled from Amphiphilic β‐Cyclodextrins 下载免费PDF全文
Zhou Ye Dr. Quan Zhang Shengtao Wang Priya Bharate Silvia Varela‐Aramburu Prof. Mengji Lu Prof. Peter H. Seeberger Prof. Jian Yin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(43):15216-15221
Multivalent mannose‐functionalized nanoparticles self‐assembled from amphiphilic β‐cyclodextrins (β‐CDs) facilitate the targeted delivery of anticancer drugs to specific cancer cells. Doxorubicin (DOX)‐loaded nanoparticles equipped with multivalent mannose target units were efficiently taken up via receptor‐mediated endocytosis by MDA‐MB‐231 breast cancer cells that overexpress the mannose receptor. Upon entering the cell, the intracellular pH causes the release of DOX, which triggers apoptosis. Targeting by multivalent mannose significantly improved the capability of DOX‐loaded nanoparticles to inhibit the growth of MDA‐MB‐231 cancer cells with minimal side effects in vivo. This targeted and controlled drug delivery system holds promise as a nanotherapeutic for cancer treatment. 相似文献