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排序方式: 共有1663条查询结果,搜索用时 16 毫秒
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Margarita J. Ramírez-Moreno Issis C. Romero-Ibarra Mateo González-de Gortari Ángeles Hernández-Pérez Heriberto Pfeiffer 《Journal of Porous Materials》2016,23(5):1155-1162
The adsorption properties of N2 and CO2 of MCM-41 and derived alkali-containing samples were analyzed over a wide range of pressures (up to ~4500 kPa) and temperatures (between 30 and 300 °C). The high-pressure and high-temperature experiments were carried out on pure MCM-41 and K- and Na-impregnated derived samples. It was analyzed the influence of pressure and temperature on the CO2 capture capacity on pure and impregnated samples. The adsorption performance was correlated to the structure and textural properties of the materials using X-ray diffraction and N2 adsorption–desorption measurements. The addition of an alkaline element changes the textural properties of the material increasing the pore size, which positively affected the CO2 adsorption capacity of these materials at high pressure. In addition, the isosteric heats of adsorption gave information about the chemical affinity between the impregnated materials and CO2. The CO2 adsorption at ~ 4500 kPa for the samples with 5 wt% Na at 100 and 200 °C were 77.98 and 9.79 mmol g?1, respectively, while the pure MCM-41 adsorbs only 8.92 mmol g?1. 相似文献
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A first approach towards the development of geographical origin tracing models for North Moroccan olive oils based on triacylglycerols profiles 下载免费PDF全文
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The controlled synthesis of narrowly distributed low molecular weight polymers with functionalization possibilities is of great industrial interests. Although living polymerization allows for control over polymer architecture, the production of low molecular weight polymers with low polydispersities via living polymerization systems is challenged by the use of large amounts of catalysts and broadening in molecular weight distribution. This review addresses the synthesis of narrowly distributed, functional, low molecular weight polyethylene and polyethylene mimics. The review is structured for quick identification of relevant systems for the production of specific polymer architectures with specific cost, efficiency, and safety concerns. 相似文献
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Albert Maim-Barcel Lucía Martín-Saiz Jos A. Fernndez Karim Prez-Romero Santiago Garfias-Arjona Mnica Lara-Almúnia Javier Pirola-Lopetegui Joan Bestard-Escalas Gwendolyn Barcel-Coblijn 《International journal of molecular sciences》2022,23(6)
Glioblastoma (GBM) represents one of the deadliest tumors owing to a lack of effective treatments. The adverse outcomes are worsened by high rates of treatment discontinuation, caused by the severe side effects of temozolomide (TMZ), the reference treatment. Therefore, understanding TMZ’s effects on GBM and healthy brain tissue could reveal new approaches to address chemotherapy side effects. In this context, we have previously demonstrated the membrane lipidome is highly cell type-specific and very sensitive to pathophysiological states. However, little remains known as to how membrane lipids participate in GBM onset and progression. Hence, we employed an ex vivo model to assess the impact of TMZ treatment on healthy and GBM lipidome, which was established through imaging mass spectrometry techniques. This approach revealed that bioactive lipid metabolic hubs (phosphatidylinositol and phosphatidylethanolamine plasmalogen species) were altered in healthy brain tissue treated with TMZ. To better understand these changes, we interrogated RNA expression and DNA methylation datasets of the Cancer Genome Atlas database. The results enabled GBM subtypes and patient survival to be linked with the expression of enzymes accounting for the observed lipidome, thus proving that exploring the lipid changes could reveal promising therapeutic approaches for GBM, and ways to ameliorate TMZ side effects. 相似文献
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Gabriela Loscalzo Julia Scheel Jos Santiago Ibaez-Cabellos Eva García-Lopez Shailendra Gupta Jos Luis García-Gimenez Salvador Mena-Moll Alfredo Perales-Marín Jos Morales-Rosell 《International journal of molecular sciences》2022,23(1)
In a prospective study, 48 fetuses were evaluated with Doppler ultrasound after 34 weeks and classified, according to the cerebroplacental ratio (CPR) and estimated fetal weight (EFW), into fetuses with normal growth and fetuses with late-onset fetal growth restriction (LO-FGR). Overexpression of miRNAs from neonatal cord blood belonging to LO-FGR fetuses, was validated by real-time PCR. In addition, functional characterization of overexpressed miRNAs was performed by analyzing overrepresented pathways, gene ontologies, and prioritization of synergistically working miRNAs. Three miRNAs: miR-25-3p, miR-185-5p and miR-132-3p, were significantly overexpressed in cord blood of LO-FGR fetuses. Pathway and gene ontology analysis revealed over-representation of certain molecular pathways associated with cardiac development and neuron death. In addition, prioritization of synergistically working miRNAs highlighted the importance of miR-185-5p and miR-25-3p in cholesterol efflux and starvation responses associated with LO-FGR phenotypes. Evaluation of miR-25-3p; miR-132-3p and miR-185-5p might serve as molecular biomarkers for the diagnosis and management of LO-FGR; improving the understanding of its influence on adult disease. 相似文献