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41.
Skeletal muscle metabolism in Duchenne muscular dystrophy (DMD): an in-vitro proton NMR spectroscopy study 总被引:1,自引:0,他引:1
The metabolic differences in the skeletal muscle of patients with Duchenne muscular dystrophy (DMD) and normal subjects (controls) were investigated using in-vitro high-resolution proton NMR spectroscopy. In all, 56 metabolites were unambiguously identified in the perchloric acid extract of muscle tissue using one- and two-dimensional NMR. The concentrations of glycolytic substrate glucose (Glc; p < 0.05), gluconeogenic amino acids such as glutamine (Gln; p < 0.05) and alanine (Ala; p < 0.05) and the glycolytic product lactate (Lac; p < 0.05) were statistically significantly lower in DMD patients as compared to controls. A significant reduction in the concentrations of total creatine (TCr; p < 0.05), glycerophosphoryl choline + phosphoryl choline + carnitine (GPC/PC/Car; p < 0.05), choline (Cho; p < 0.05) and acetate (Ace; p < 0.05) was also observed in these patients. Decrease in the level of glucose may be attributed to the reduction in the concentrations of gluconeogenic substrates or membrane abnormalities in degenerated muscle of DMD patients. Lower levels of choline containing compounds indicate membrane abnormalities. Decrease in the concentration of lactate in the muscle of DMD patients may be due to the reduction in anaerobic glycolytic activity or lower substrate concentration. The decrease in the concentration of acetate may reflect reduced transport of fatty acids into mitochondria due to decreased concentration of carnitine in DMD patients. Kreb's cycle intermediate alpha-ketoglutarate was observed only in the diseased muscle, which is suggestive of predominant oxidative metabolism for energy generation. 相似文献
42.
Polymer electrolyte films prepared from poly (methyl methacrylate) and LiAsF6 with different concentrations of plasticizer (DBP) are described. The formation of polymer-salt complexes has been confirmed
by XRD and FTIR spectral studies. The temperature dependence of the conductivity of the polymer films obeys the VTF relation.
Values of conductivities of the polymer complexes are presented and discussed. 相似文献
43.
Sonal M. Patel Uma V. Chudasama Pralhad A. Ganeshpure 《Reaction Kinetics and Catalysis Letters》2002,76(2):317-325
Metal(IV) phosphates of tin, zirconium and titanium in different morphological forms, viz. amorphous, calcined and crystalline, have been used as catalysts for selective cyclodehydration of 1,4-butanediol to tetrahydrofuran. A comparative study of the three catalysts for the above reaction has been carried out to understand the effect of their composition and morphology on the catalytic activity. 相似文献
44.
45.
Near infrared (NIR) spectrometry was used for the rapid characterization of quality parameters in desi chickpea flour (besan). Partial least square regression, principal component regression (PCR), interval partial least squares (iPLS), and synergy interval partial least squares (siPLS) were used to determine the protein, carbohydrate, fat, and moisture concentrations of besan. Spectra were collected in reflectance mode using a lab-built predispersive filter-based instrument from 700 to 2500?nm. The quality parameters were also determined by standard methods. The root mean square error (RMSE) for the calibration and validation sets was used to evaluate the performance of the models. The correlation coefficients for moisture, fat, protein, and carbohydrates in chickpea flour exceeded 0.96 using PLS and PCR models using the full spectral range. Wavelengths from 2100 to 2345?nm had the lowest RMSE for quality parameters by iPLS. The error was further decreased by 0.41, 0.1, and 1.1% for carbohydrates, fats, and proteins by siPLS. The NIR spectral regions yielding the lowest RMSE of prediction were 1620–2345?nm for carbohydrates, 1180–1590?nm and 1860–2094?nm for fat, and 1700–2345?nm for proteins. The study shows that chickpea flour quality parameters were accurately determined using the optimized wavelengths. 相似文献
46.
Overall measurement of methanogenic activity of sludge and or slurry is thought as a key for understanding the basic physiology
of anaerobic consortia involved in anaerobic digestion process of an alternative biomass. In this study, the methanogenic
activity of biogas plant slurry was used to evaluate the anaerobic digestion of ossein factory wastes such as sinews and primary
clarified bone waste (PCBW) and cyanobacterial biomass in standard assay conditions. A maximum methanogenic activity was reported
here when ossein factory wastes mixed with cyanobacterial biomass in specific proportions in which sinews and PCBW alone also
favored to a significant methane yield. Cyanobacterial biomass alone did not give a desirable methanogenic activity. Approximately
48% of total solids were destroyed from these wastes after 30 days. This study gives information on the use of these wastes
with suitable proportions for taking an effort in a large-scale anaerobic digestion in an effective way of ossein factory. 相似文献
47.
Bipin Singh Koranga Mohan Narayan S. Uma Sankar 《International Journal of Theoretical Physics》2011,50(5):1515-1521
The recent measurement of Δ
sol
by the KamLAND experiment with very small errors, makes definitive predictions for the energy dependence of the solar neutrino
survival probability P
ee
. We fix Δ
sol
to be the KamLAND best fit value of 8×10−5 eV2 and study the energy dependence of P
ee
for solar neutrinos, in the framework of two flavour oscillations and also of three flavour oscillations. For the case of
two flavour oscillations, P
ee
has a measurable slope in the 5–8 MeV range but the solar spectrum measurements in this range find P
ee
to be flat. The predicted values of P
ee
, even for the best fit value of θ
sol
, differ by 2–3 σ from the Super-K measured values in each of the three energy bins of the 5–8 MeV range. If future measurements of solar neutrinos
by Super-K and SNO find a flat spectrum with reduced error bars (by a factor of 2), it will imply that two flavour oscillations
can no longer explain both KamLAND data and the solar spectrum. However a flat solar neutrino spectrum and the Δ
sol
measured by KamLAND can be reconciled in a three flavour oscillation framework with a moderate value of θ
13≈13°. 相似文献
48.
In this paper dynamic routing and wavelength assignment strategies have been proposed for multiclass WDM optical networks. Multiclass optical networks provide multiple classes of services to the subscriber according to the requirement, which in turn increase operational profitability. Each class of service could be characterized by parameters like number of wavelengths, expected call holding time and average arrival rate of request. The proposed strategies have been analyzed and compared with existing strategies on the basis of blocking probabilities for multiclass traffic scenarios. Simulation results on different network topologies demonstrate that the performance of proposed strategies “Fixed shortest/alternate shortest path routing with wavelength reservation (FSASWR)” and “Fixed alternate shortest path routing with least priority wavelength assignment (FASPL)” are much better as compared to existing strategies. Proposed strategies minimize blocking probability of the multiclass network using limited number of wavelengths. 相似文献
49.
K. Rajender Reddy M. Venkateshwar C. Uma Maheswari P. Santhosh Kumar 《Tetrahedron letters》2010,51(16):2170-1420
An efficient synthesis of 1-iodoalkynes and iodophenols was easily achieved by employing simple KI and TBHP. The reaction does not involve the use of a metal and base combination. A variety of substituted alkynes and phenols were prepared with good to excellent yield. 相似文献
50.
P. S. Anjana V. Deepu S. Uma P. Mohanan J. Philip M. T. Sebastian 《Journal of Polymer Science.Polymer Physics》2010,48(9):998-1008
Cerium oxide‐filled high density polyethylene (HDPE) composites for microwave substrate applications were prepared by sigma‐blend technique. The HDPE was used as the matrix and the dispersion of CeO2 in the composite was varied up to 0.5 by volume fraction, and the dielectric properties were studied at 1 MHz and microwave frequencies. The variations of thermal conductivity (keff), coefficient of thermal expansion (αc) and Vicker's microhardness with the volume fraction of the filler were also measured. The relative permittivity (εeff) and dielectric loss (tan δ) were found to increase with increase in CeO2 content. For 0.4 volume fraction loading of the ceramic, the composite had εeff = 5.7, tan δ = 0.0068 (at 7 GHz), keff = 2.6 W/m °C, αc = 98.5 ppm/°C, Vicker's microhardness of 18 kg/mm2 and tensile strength of 14.6 MPa. Different theoretical approaches have been used to predict the effective permittivity, thermal conductivity, and coefficient of thermal expansion of composite systems and the results were compared with the experimental data. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 998–1008, 2010 相似文献