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排序方式: 共有909条查询结果,搜索用时 234 毫秒
901.
902.
Mode of action of lipoic acid in diabetes 总被引:1,自引:0,他引:1
Metabolic aberrations in diabetes such as hyperglycemia, ketonemia, ketonuria, reduced glycogen in tissues and reduced rates
of fatty acid synthesis in the liver are corrected by the administration of lipoic acid. Dithiol octanoic acid is formed from
lipoic acid by reduction and substitutes for Coenzyme A in several enzymatic reactions such as pyruvate dehydrogenase, citrate
synthase, acetyl Coenzyme A carboxylase, fatty acid synthetase, and triglyceride and phospholipid biosynthesis; but not in
the oxidation of fatty acids because of the slow rates of thiolysis of β-keto acyl dithioloctanoic acid. The overall effect
of these changes in the key enzymic activities is seen in the increased rates of oxidation of glucose and a reduction in fatty
acid oxidation in diabetes following lipoic acid administration. 相似文献
903.
Milk proteins are crucial for the development of all newborn mammals. Caseins that constitute the bulk of the protein in mammalian milk have been shown to be members of a multigene family in at least two species. They are among the most rapidly diverging groups of proteins, and their numbers vary widely among species. beta- and kappa-Caseins are the only caseins present in human milk. Using polymerase chain reaction on genomic DNA from somatic cell hybrids, we have localized the human beta-casein gene (CSN2) to 4pter----q21. 相似文献
904.
James F. Ponder Akanksha K. Menon Raghunath R. Dasari Sandra L. Pittelli Karl J. Thorley Shannon K. Yee Seth R. Marder John R. Reynolds 《Liver Transplantation》2019,9(24)
Conjugated polymers with high electrical conductivities are attractive for applications in capacitors, biosensors, organic thermoelectrics, and transparent electrodes. Here, a series of solution processable dioxythiophene copolymers based on 3,4‐propylenedioxythiophene (ProDOT) and 3,4‐ethylenedioxythiophene (EDOT) is investigated as thermoelectric and transparent electrode materials. Through structural manipulation of the polymer repeat unit, the conductivity of the polymers upon oxidative solution doping is tuned from 1 × 10?3 to 3 S cm?1, with a polymer consisting of a solubilizing alkylated ProDOT unit and an electron‐rich biEDOT unit (referred to as PE2) showing the highest electrical conductivity. Optimization of the film casting method and screening of dopants result in AgPF6‐doped PE2 achieving a high electrical conductivity of over 250 S cm?1 and a thermoelectric power factor of 7 μW m?1 K?2. Oxidized spray cast films of PE2 are also assessed as a transparent electrode material for use with another electrochromic polymer. This bilayer shows reversible electrochemical switching from a colored charge‐neutral state to a highly transmissive color‐neutral, oxidized state. These results demonstrate that dioxythiophene‐based copolymers are a promising class of materials, with ProDOT–biEDOT serving as a soluble analog to the well‐studied PEDOT as a p‐type thermoelectric and electrode material. 相似文献
905.
Claire Rooney Catherine Geh Victoria Williams Johannes M. Heuckmann Roopika Menon Petra Schneider Katherine Al-Kadhimi Michael Dymond Neil R. Smith Dawn Baker Tim French Paul D. Smith Elizabeth A. Harrington J. Carl Barrett Elaine Kilgour 《PloS one》2016,11(2)
FGFR1 amplification occurs in ~20% of sqNSCLC and trials with FGFR inhibitors have selected FGFR1 amplified patients by FISH. Lung cancer cell lines were profiled for sensitivity to AZD4547, a potent, selective inhibitor of FGFRs 1–3. Sensitivity to FGFR inhibition was associated with but not wholly predicted by increased FGFR1 gene copy number. Additional biomarker assays evaluating expression of FGFRs and correlation between amplification and expression in clinical tissues are therefore warranted. We validated nanoString for mRNA expression analysis of 194 genes, including FGFRs, from clinical tumour tissue. In a panel of sqNSCLC tumours 14.4% (13/90) were FGFR1 amplified by FISH. Although mean FGFR1 expression was significantly higher in amplified samples, there was significant overlap in the range of expression levels between the amplified and non-amplified cohorts with several non-amplified samples expressing FGFR1 to levels equivalent to amplified samples. Statistical analysis revealed increased expression of FGFR1 neighboring genes on the 8p12 amplicon (BAG4, LSM1 and WHSC1L1) in FGFR1 amplified tumours, suggesting a broad rather than focal amplicon and raises the potential for codependencies. High resolution aCGH analysis of pre-clinical and clinical samples supported the presence of a broad and heterogeneous amplicon around the FGFR1 locus. In conclusion, the range of FGFR1 expression levels in both FGFR1 amplified and non-amplified NSCLC tissues, together with the breadth and intra-patient heterogeneity of the 8p amplicon highlights the need for gene expression analysis of clinical samples to inform the understanding of determinants of response to FGFR inhibitors. In this respect the nanoString platform provides an attractive option for RNA analysis of FFPE clinical samples. 相似文献
906.
907.
An improved chemiluminescence assay suggests non nitric oxide-mediated action of lysophosphatidylcholine and acetylcholine 总被引:2,自引:0,他引:2
N K Menon A Wolf M Zehetgruber R J Bing 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1989,191(3):316-319
Using a new nitric oxide analyser, we have developed a sensitive chemiluminescence assay to detect trace quantities of NO in aqueous solutions. This improved technique in combination with the bioassay has been employed to verify the theory that NO released by vascular endothelium, accounts for the relaxation produced by acetylcholine, lysophosphatidylcholine and calcium ionophore A23187. Our results show that while calcium ionophore A23187 continuously released NO, acetylcholine and lysophosphatidylcholine relaxed vascular strips without releasing NO over the basal level. 相似文献
908.
The activity of 3-hydroxy-3-methylglutaryl-CoA (HMGCoA) reductase of rat liver microsomes was inhibited by the addition of FeSO4 and the cytosolic protein, fermodulin. Modulation of the activity was obtained only in the combined presence of Fe2+ and fermodulin. Using ammonium sulfate fractionation, heat treatment, and chromatography on CM-Sephadex and then on an Fe2+-Blue Sepharose affinity matrix, fermodulin was purified to homogeneity. The molecular weight of the purified protein, as determined by filtration through a Sephacryl S-200 column, was 58,000. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis the protein resolved into two subunits of Mr 43,000 and 28,000. Fermodulin showed ultraviolet absorption and fluorescence spectra typical of tryptophan-containing proteins, and addition of FeSO4 quenched the fluorescence. Using the Millipore filter assay the binding of 1.6 mol 55FeCl2/mol fermodulin was observed in the presence of Tris-HCl buffer. The inhibitory effect of fermodulin at nonsaturating concentrations was potentiated by bicarbonate, ATP.Mg, and ADP.Mg. 相似文献
909.