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61.
Summary. Fatty acid oxidation is usually thought of as being a preferred ATP source during sepsis, as shown by the decrease in respiratory quotient in septic patients and animals. However, fatty acid oxidation may be impaired relative to circulating triglyceride levels, resulting in increased cycling between triglycerides and non-esterified fatty acids. The rate of fatty acid oxidation is critically dependent on the stage of sepsis. Carnitine may be depleted during sepsis by a combination of muscle wasting, erythrocyte haemolysis, decreased tissue uptake, reduced kidney reabsorption of free carnitine, and increased excretion of acyl-carnitines. Whether there may be any beneficial effects of carnitine supplementation during sepsis, is, as yet, uncertain.  相似文献   
62.
1,3-Alternate calix[4]arenes, decorated with four nonpolar ‘all-trans’ tetracyclic nuclei and cation-stabilizing β-methoxyethoxy appendages, were synthesized from commercially available starting materials and through straightforward functional groups transformations/couplings. Their Na+-transport activities, when compared with those exerted by the known conformationally-rigidified 1,3-alternate calix[4]arene AB/cis cholic acid conjugates, suggest that the cation conductance is related to the morphology of the pendant steroids.  相似文献   
63.
The bottom-up fabrication of synthetic cells (protocells) from molecules and materials, is a major challenge of modern chemistry. A significant breakthrough has been the engineering of protocells capable of chemical communication using bio-derived molecules and ex situ stabilised cell machineries. These, however, suffer from short shelf-lives, high costs, and require mild aqueous conditions. In this Concept Article we analyse the chemistry at the heart of protocell communication to highlight new opportunities for synthetic chemists in protocell engineering. Specifically, we (i) categorise the main bio-derived chemical communication machineries in enzyme cascades, DNA strand displacement, and gene-mediated communication; (ii) review the chemistries of these signal transduction machineries; and (iii) introduce new types of bio-inspired, fully synthetic artificial enzymes to replace their natural counterparts. Developing protocells that incorporate synthetic analogues of bio-derived signal transduction machineries will improve the robustness, stability, and versatility of protocells, and broaden their applications to highly strategic fields such as photocatalysis and fine chemicals production.  相似文献   
64.
The coadsorption of Na with CO and O on Ni(111) is studied by high‐resolution electron energy loss spectroscopy. Experimental evidence for a very short‐range interaction between Na and coadsorbates is reported, in contrast with recent theoretical predictions overestimating nonlocal alkali‐induced effects. Loss spectra show distinct features, as a consequence of different local [CO]:[Na] and [O]:[Na] stoichiometries.  相似文献   
65.
The present research is focused on the use of comprehensive 2-D GC (GCxGC) for the thorough elucidation of fatty acid (FA) profiles contained in vegetable oils; the samples analysed consisted of extra-virgin olive oil and refined hazelnut oil. The enhanced sensitivity and the formation of group-type patterns provided by GCxGC enabled the identification and quantification of both well-known and rather unexpected FAs contained in the lipid matrices. Peak assignment was, in most cases, supported by using pure standard compounds. Of particular interest was the identification of a series of odd-numbered FAs in both samples. The results attained to demonstrate the usefulness of GCxGC also for the analysis of supposedly low-complex samples.  相似文献   
66.
The interaction of oxygen with alkalis (Na, K) on Ni(111) was studied by high-resolution electron energy loss spectroscopy. Loss measurements revealed for the first time a softening of the O-Ni bond and, simultaneously, a strengthening of the alkali-Ni bond in the alkali+O coadsorbed phase, in perfect agreement with recent theoretical calculations. The weakening of the O-Ni bond was ascribed to the alkali-induced filling of the O 2p(z) antibonding orbitals. Different physical mechanisms were discussed for explaining the strengthening of the alkali-substrate bond whenever alkalis are coadsorbed with O adatoms.  相似文献   
67.
A preliminary Raman investigation of the ionic liquid N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR(13)TFSI) and its 2/1 complex with the lithium salt LiN(SO(2)CF(3))(2) is reported. The study was performed over a temperature range extending from -100 to +60 degrees C, i.e., with PYR(13)TFSI in the crystalline and melt states. For comparison purposes, the study was extended to PYR(13)I, which is the precursor used in the synthesis of PYR(13)TFSI.  相似文献   
68.
Some small molecules, such as phthalocyanines, capable of exhibiting greatly enhanced capacities and acting as internal tags, are shown to be effective as replacements for polydisperse polyethylene glycols, in soluble polymer-supported type synthesis of some piperidine and piperazine derivatives.  相似文献   
69.
Journal of Radioanalytical and Nuclear Chemistry - The application of the k0-standardization method of neutron activation analysis offers the great advantage to perform multi-elemental analyses...  相似文献   
70.
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