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101.
Prostaglandin D2 synthase (PGDS) (beta-trace protein) is a highly abundant cerebrospinal fluid (CSF) glycoprotein. A number of studies have been performed to determine the potential value of this protein for the diagnosis of various neurological disorders. The measurement of total PGDS levels in CSF has proved marginally useful for this purpose, but promising results were obtained while investigating changes in the posttranslational modifications (PTM) pattern. Using 2-DE analysis, we previously showed that PGDS is differentially expressed in ante- and post mortem CSF samples. In the present study, we examined whether the PGDS isoforms may help to distinguish stroke and neurodegenerative disease patients from healthy subjects. The pattern of PGDS PTM was analyzed in CSF from patients with various neurological disorders (n = 44) using IEF/immunoblotting techniques. Strong alterations of this pattern were detected in patients with different forms of degenerative dementia. These findings are consistent with PGDS being altered in some neurological diseases and provide new opportunities for clinical applications. 相似文献
102.
Martínez-Lozano JA Marín MJ Tena F Utrillas MP Sánchez-Muniosguren L González-Frías C Cuevas E Redondas A Lorente J de Cabo X Cachorro V Vergaz R de Frutos A Díaz JP Expósito FJ de la Morena B Vilaplana JM 《Photochemistry and photobiology》2002,76(2):181-187
An analysis is made of experimental ultraviolet erythemal solar radiation data measured during the years 2000 and 2001 by the Spanish UV-B radiation evaluation and prediction network. This network consists of 16 Robertson-Berger type pyranometers for evaluating solar erythemal radiation and five Brewer spectroradiometers for evaluating the stratospheric ozone. On the basis of these data the Ultraviolet Index (UVI) was evaluated for the measuring stations that are located either in coastal regions or in the more densely populated regions inland on the Iberian Peninsula. It has been checked that in most cases the maximum irradiance values corresponded to solar noon, although there were exceptions that could be explained by cloudiness. The maximum experimental values of the UVI were around 9 during the summer, though frequently passing this value at the inland measurement stations. The annual accumulated dose of irradiation on a horizontal plane has also been studied, as well as the evolution through the year in units of energy, standard erythemal doses and minimum erythemal doses, according to different phototypes. 相似文献
103.
H. Dupont Durst Luis Echegoyen George W. Gokel Angel Kaifer 《Tetrahedron letters》1982,23(43):4449-4452
The 13C spin-lattice relaxation times (T1's) of cryptands [2.1.1], [2.2.1] and [2.2.2] as well as those of the corresponding cryptate complexes with Li+, Na+, and K+ in CDCl3 and CH3OH:D2O (90:10) were measured and the results are interpreted in terms of molecular compression and desolvation effects. 相似文献
104.
Gas chromatography-mass spectrometry with the mass spectrometer operated in the tandem mode at a constant accelerating voltage was used to analyse for triterpanes in Arabian crude oils. Specific molecular parent-daughter ion pairs were selected for quantitative measurements owing to their metastable transitions in the first field-free region. More accurate relative distribution ratios of hydrocarbon biomarkers were determined by this sequential gating technique than by the conventional diagnostic daughter ion mass fragmentogram in common GC-MS. The data and spectra obtained from MS-MS operation may serve as unique “fingerprints” for these regional crudes 相似文献
105.
Steady-state mass transfer experiments were done to determine whether certain strains of bacteria in homogeneous suspension will accumulate at the gas:liquid interface and thereby significantly increase the oxygen transfer rate to the suspension. In particular, with suspensions ofB. licheniformis, the measured transfer rates are as much as three times the rate expected for a uniform suspension. In contrast, suspensions ofM. luteus show no increase in oxygen flux above expected values. The fact thatB. licheniformis is motile, whereasM. luteus is not suggests that cell motility may play an important role in the accumulation process.
相似文献106.
Jos Luis Lpez Marcos Mandado Ana M. Graa Ricardo A. Mosquera 《International journal of quantum chemistry》2002,86(2):190-198
The atomic and bond properties of a series of alkanenitriles were calculated in order to analyze the transferability of the CN, methyl, and methylene groups. The calculations were carried out using the atoms in molecules (AIM) theory on RHF/6‐31++G**// RHF/6‐31G** wave functions obtained for compounds CN–R (R ranging from H to C11H23). Linear correlations between L(Ω) and N(Ω) were used to establish N(CH2) and N(CH3) nearly transferable values. Average values and maximum differences to the mean value of several properties were used for classifying the CN group. It shows a transferable behavior along the CN–R series for R>Et. The methyl group presents specific properties when R<Pr. The methylene groups can be classified considering both their position with respect to the end of the chain and the position with respect to the CN group. The atomic energy displays a dependence on the molecular size. Although this behavior does not allow to consider this property as transferable, both the ab initio total electronic molecular energies and the experimental heats of formation can be fitted, by linear regression analysis, as a function of the number of methylene groups. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001 相似文献
107.
De La Rosa Luis B. Reshamwala Sultan Latimer Vivian M. Shawky Bahaa T. Dale Bruce E. Stuart Earnest D. 《Applied biochemistry and biotechnology》1994,(1):483-497
The herbaceous crops that may provide fermentable carbohydrates for production of fuels and chemicals also contain 10–20%
protein. Protein coproduction with biomass-derived fuels and chemicals has important advantages: (1) food and fuel production
can be integrated, and (2) protein is a high-value product that may significantly improve overall process economics. We report
the results of an integrated approach to producing protein and fermentable sugars from one herbaceous species, Coastal Bermudagrass
(CBG). The ammonia fiber explosion (AFEX) process makes possible over 90% conversion of cellulose and hemicellulose to simple
sugars (about 650 mg reducing sugars/g dry CBG) at 5 IU cellulase/g vs < 20% conversion for untreated CBG. The AFEX treatment
also improves protein extraction from CBG; over 80% protein recovery is possible from AFEX-treated CBG vs about 30% recovery
from untreated CBG. 相似文献
108.
Quassinoids from Picrasma crenata 总被引:1,自引:0,他引:1
From woods of Picrasma crenata, a new stereoisomer dihydronorneoquassin was obtained together with others well knowns dihydronorneoquassin, parain, alpha-neoquassin, beta-neoquassin and quassin. The structures were determined by spectroscopic data and chemical evidence. 相似文献
109.
Diego Pallarola Luis Domenianni Graciela Priano Fernando Battaglini 《Electroanalysis》2007,19(6):690-697
In this work, two well known polymers, carboxymethyl dextran and poly(ethyleneglycol), are used for easily producing a platform for electrochemical affinity assays, avoiding nonspecific adsorption of proteins. In this way, modified electrode surfaces able to bind a recognition agent are constructed through simple and reliable reactions. 相似文献
110.
G. Rauret R. Rubio L. Pineda J. F. López Sanchez J. L. Beltran 《Fresenius' Journal of Analytical Chemistry》1991,341(10):631-635
Summary For studying the mechanisms of trace metal mobilization in sediments several strategies have been employed, such as single extraction, sequential extractions, ion exchange, or progressive acidification. Several authors assert that sequential extraction is the best option. In this study two procedures are used in order to assess the mobility of copper and lead in heavily polluted river sediments: sequential extraction using a modified Tessier procedure, and progressive acidification, using an automated method. Six heavily polluted sediment samples are studied by applying the two procedures. The amount of metal released at different pH-values (pH 5 and pH 2) is compared with the resulting distribution when the sequential extraction procedure is applied. The information obtained from the two different approaches is discussed. For both metals a different behaviour is observed when applying each of the two procedures. Thus, copper is more easily released than lead when progressive acidification is followed, whereas an inverse situation is observed when sequential extraction is applied. 相似文献