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排序方式: 共有1119条查询结果,搜索用时 15 毫秒
991.
Lionel Ripoll Claire Bordes Pedro Marote Sabrina Etheve Abdelhamid Elaissari Hatem Fessi 《Polymer International》2012,61(7):1127-1135
The adsorption of amino‐functionalized poly(methyl methacrylate) particles prepared by emulsion polymerization onto polyamide/elastane fibres was investigated. The influence of several physicochemical parameters (pH, ionic strength) on the colloidal stability and surface properties of the cationic latex particles was first examined. Then, particle adsorption was studied as a function of particle concentration, particle size, time, pH and salinity. The results obtained demonstrated that the adsorption process was mainly governed by electrostatic interactions and the adsorption isotherms were analysed on the basis of a Langmuir model. Finally, the effect of washing steps on the adsorbed particles was investigated. The results obtained indicated strong interactions between particles and textile fibres. Copyright © 2012 Society of Chemical Industry 相似文献
992.
Sabrina Sartori Xiumei Qi Nico Eigen Jiri Muller Thomas Klassen Martin Dornheim Bjørn C. Hauback 《International Journal of Hydrogen Energy》2009
In this work Mg- and K-containing alanates have been investigated as possible hydrogen storage materials. Ball milling was carried out under argon or at moderate/high hydrogen pressure in order to obtain an improved driving force for the formation of potential new alanate phases. Powder X-ray diffraction and volumetric measurements were used in order to identify reaction mechanisms and phases forming in these systems. New unidentified peaks were detected for the mixtures 2MgH2 + 3Al + KH and 2CaH2 + Al + 2KH. However, they do not seem to belong to reversible hydride phases. 相似文献
993.
Lina Chianese Maria Quarto Fabiana Pizzolongo Maria Grazia Calabrese Simonetta Caira Rosalba Mauriello Sabrina De Pascale Francesco Addeo 《International Dairy Journal》2009,19(4):181-189
A study on casein genetic polymorphism in water buffalo milk of Mediterranean breed, reared in Southern Italy, was carried out by means of immunoelectrophoretic and chromatographic techniques coupled with mass spectrometry analysis. When compared with reference αs1-CN variant A, the results showed the occurrence of a new αs1-casein (αs1-CN) B genetic variant having a single silent amino acid substitution Leu178(A) → Ser178(B). In Mediterranean buffalo milks the allelic frequency of new αs1-CN B was very similar to that determined in Mozzarella di bufala campana (MBC), a Protected Denomination of Origin (PDO) cheese, made exclusively from whole raw buffalo milk of this breed. The relative percentage of the two αs1-CN variants, either in bulk milk or MBC cheese, can be used in defining the authenticity of PDO MBC cheese. 相似文献
994.
Bahador Nabgan Tuan Amran Tuan Abdullah Muhammad Tahir Walid Nabgan Sugeng Triwahyono Aishah Abdul Jalil Yahya Gambo Maryam Ibrahim Kamal Moghadamian 《International Journal of Hydrogen Energy》2017,42(34):21571-21585
The effect of different pellet sizes of nickel (Ni) and lanthanum (La) promoted Al2O3 support on the catalytic performance for selective hydrogen production from polyethylene terephthalate (PET) plastic waste via steam reforming process has been investigated. The catalysts were prepared by impregnation method and were characterized using XRD, BET, TPD-CO2, TPR, SEM, EDX, TEM and TGA. The results showed that NiLa-co-impregnated Al2O3 catalyst has excellent activity for the production of hydrogen. Feed conversion of 88.53% was achieved over 10% Ni/Al2O3 catalyst which increased to 95.83% in the case of 10% Ni-5% La/Al2O3 catalysts with a H2 selectivity of 70.44%. The catalyst performance in term of gas production and feed conversion was further investigated under various operating parameters, e.g., feed flow-rate, and catalyst pellet size. It was found that at 0.4 ml/min feed flow rate, highest feed conversion and H2 selectivity were achieved. The Ni particles, which are the noble-based active species are highly effective, thus offered good hydrogen production in the phenol-PET steam reforming process. Incorporation of La as a promoter in Ni/Al2O3 catalyst has significantly increased the catalyst reusability with prolonged stability. The NiLa/Al2O3 catalyst with larger size showed remarkable activity due to the presence of significant temperature gradients inside the pellet compared to smaller size. Additionally, the catalyst showed only slight decrease in H2 selectivity and feed conversion even after 24 h, although production of carbon nanotubes was evidenced on its surface. 相似文献
995.
N.N. Ramly N.A. Aini N. Sahli S.F. Aminuddin M.Z.A. Yahya A.M.M. Ali 《International Journal of Hydrogen Energy》2017,42(14):9284-9292
Proton exchange membrane materials based on sulfonated poly ether ether ketone (SPEEK) with Methyl Cellulose (MC) are developed by solution cast technique and exposed to UV radiation with Bezoin Ethyl Ether (BEE) as photoinitiator. The addition of MC into SPEEK polymer enhances the conductivity up to 8.7 × 10?3 Scm?1 at 30 °C temperature and 80% relative humidity. This new crosslinked hybrid membrane shows good prospect for the use as proton exchange membrane in fuel cell. 相似文献
996.
Mourad Assidi Fatimah M. Yahya Maryam H. Al-Zahrani Razan Elkhatib Ali Zari Aisha Elaimi Jaudah Al-Maghrabi Ashraf Dallol Abdelbaset Buhmeida Muhammad Abu-Elmagd 《International journal of molecular sciences》2021,22(23)
Ovarian cancer (OC) is the deadliest among all gynecological cancers. Epidemiological studies showed that obesity might influence many cancers including OC. One of the key factors that may link obesity and OC is leptin (LEP), known as an adipokine with pleiotropic effects on body homeostasis. This study aims to investigate the expression pattern of LEP, assess the methylation profiles of LEP and their associations with clinicopathological features including survival outcomes of OC patients. The protein expression of LEP was evaluated in 208 samples using both tissue microarray and immunohistochemistry techniques. The methylation profiles of LEP were measured in 63 formalin-fixed, paraffin-embedded tumor tissues by quantitative polymerase chain reaction using a MethyLight assay. Our results showed a significant association of LEP protein overexpression with several clinicopathological variables, mainly tumor subtype, LVI, age of menarche, tumor size and stage (p < 0.04). Kaplan–Meier analysis (using low expression versus high expression as a discriminator) indicated that LEP protein overexpression is a powerful positive prognosticator of both OC recurrence (DFS) and disease-specific survival (DSS) in our OC cohort (log-rank p = 0.01 and p = 0.002, respectively). This implies that patients with high LEP expression profiles live longer with less recurrence rates. Methylation analysis results demonstrated a clear association between no/low LEP protein expression pattern (38%) and LEP promoter CpG island hypermethylation (43%). Results of this study suggest that LEP is a powerful prognosticator of OC recurrence and DSS. LEP expression in OC seems to be regulated by its promoter hypermethylation through gene partial/total silencing. Further multi-institutional studies using larger cohorts are required to demystify the intricate molecular functions of this leptin-driven effects in OC pathophysiology and to accurately assess its theranostic potential and validate its prognostic/predictive power in OC onset, progression towards more effective and personalized management of OC patients. 相似文献
997.
Grgorio Crini Ludovic Janus Michel Morcellet Giangiacomo Torri Annamaria Naggi Sabrina Bertini Carmen Vecchi 《应用聚合物科学杂志》1998,69(7):1419-1427
Macroporous beads containing N-vinyl-tertio-butyl carbamate (NVTBC) have been prepared by suspension copolymerization using divinylbenzene as crosslinking agent. After solvolysis, parent copolymers containing vinylamine (VA) were functionalized by β-cyclodextrin (β-CD) using the mono-tosyl derivative of β-CD as the intermediate (β-CDOTs). Several copolymers with various degrees of substitution were synthesized. Several factors (reaction time, amounts of the reactants, composition of solvent, and temperature) were studied. Characterization was achieved by crosspolarization magic angle spinning nuclear magnetic resonance spectroscopy (CPMAS NMR). The textural features (specific area and porous volume) of the beads were also determined. These insoluble macroporous copolymers containing β-CD were then used for the recovery of various organic pollutants from aqueous solutions. Some preliminary studies (time, concentration, kinetics, and β-CD content) are presented here. The results of sorption experiments show that they exhibit high sorption capacities toward substituted benzene derivatives. The mechanism of sorption is an acid-base interaction due to the amino groups of the polymer network and/or the formation of an inclusion complex due to the β-CD molecules. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1419–1427, 1998 相似文献
998.
Sabrina Orzetti Federica Tommasi Antonella Bertola Giorgia Bortolin Elisabetta Caccin Sara Cecco Emanuela Ferrarin Elisa Giacomin Paolo Baldo 《International journal of molecular sciences》2022,23(6)
The impressive advances in the knowledge of biomarkers and molecular targets has enabled significant progress in drug therapy for crucial diseases such as cancer. Specific areas of pharmacology have contributed to these therapeutic outcomes—mainly targeted therapy, immunomodulatory therapy, and gene therapy. This review focuses on the pharmacological profiles of these therapeutic classes and intends, on the one hand, to provide a systematic definition and, on the other, to highlight some aspects related to pharmacovigilance, namely the monitoring of safety and the identification of potential toxicities and adverse drug reactions. Although clinicians often consider pharmacovigilance a non-priority area, it highlights the risk/benefit ratio, an essential factor, especially for these advanced therapies, which represent the most innovative and promising horizon in oncology. 相似文献
999.
Timo Henneck AhmedElmontaser Mergani Sabrina Clever Anna E. Seidler Graham Brogden Sandra Runft Wolfgang Baumgrtner Katja Branitzki-Heinemann Maren von Kckritz-Blickwede 《International journal of molecular sciences》2022,23(6)
Formation of neutrophil extracellular traps (NETs) is a two-faced innate host defense mechanism, which, on the one hand, can counteract microbial infections, but on the other hand, can contribute to massive detrimental effects on the host. Cholesterol depletion from the cellular membrane by Methyl-β-cyclodextrin (MβCD) is known as one of the processes initiating NET formation. Since neutrophils mainly act in an inflammatory environment with decreased, so-called hypoxic, oxygen conditions, we aimed to study the effect of oxygen and the oxygen stress regulator hypoxia-inducible factor (HIF)-1α on cholesterol-dependent NET formation. Thus, murine bone marrow-derived neutrophils from wild-type and HIF-knockout mice or human neutrophils were stimulated with MβCD under normoxic (21% O2) compared to hypoxic (1% O2) conditions, and the formation of NETs were studied by immunofluorescence microscopy. We found significantly induced NET formation after treatment with MβCD in murine neutrophils derived from wild-type as well as HIF-1α KO mice at both hypoxic (1% O2) as well as normoxic (21% O2) conditions. Similar observations were made in freshly isolated human neutrophils after stimulation with MβCD or statins, which block the HMG-CoA reductase as the key enzyme in the cholesterol metabolism. HPLC was used to confirm the reduction of cholesterol in treated neutrophils. In summary, we were able to show that NET formation via MβCD or statin-treatment is oxygen and HIF-1α independent. 相似文献