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101.
Epilepsy affects more than 0.5% of the world population and is known to be associated with a large genetic component eliciting an electrical hyperexcitability in the central nervous system. However, its pathogenic mechanisms remain poorly understood. In order to gain greater molecular incite in the pathogenesis in epilepsy, we analyzed proteomes of human cerebral cortices. Quantitative proteome analysis was used to compare signals corresponding to individual proteins between epileptic cerebral cortices from patients with temporal lobe epilepsy and age-matched non-epileptic subjects. To minimize individual variations, gender and age of the patients were matched. Changes of several spots were consistent among 6 pairs of epileptic patients and nonepileptic subjects. One of the spots was identified as the mitochondrial type Mn-superoxide dismutase (Mn-SOD) confirmed by Western blot analysis with Mn-SOD antibody and enzyme activity assay. Such results were agreeable with chemical and physical parameters given by the 2-dimensional electrophoresis (2-DE) gel. Mn-SOD was consistently down-regulated in epileptic cerebral cortices compared with those of nonepileptic subjects. Our results demonstrate a clear link between pathogenesis of epilepsy and SOD. Additionally, we identified four proteins that were consistently over-expressed in all epileptic temporal neocortices specimens and the other four proteins that were found to be expressed less than non-epileptic control subjects. These proteomic data provide cellular markers in the understanding mechanism of the epilepsy pathogenesis. 相似文献
102.
Abe K Abe K Abe T Adam I Akimoto H Aston D Baird KG Baltay C Band HR Barklow TL Bauer JM Bellodi G Berger R Blaylock G Bogart JR Bower GR Brau JE Breidenbach M Bugg WM Burke D Burnett TH Burrows PN Calcaterra A Cassell R Chou A Cohn HO Coller JA Convery MR Cook V Cowan RF Crawford G Damerell CJ Daoudi M de Groot N de Sangro R Dong DN Doser M Dubois R Erofeeva I Eschenburg V Fahey S Falciai D Fernandez JP Flood K Frey R Hart EL Hasuko K Hertzbach SS Huffer ME Huynh X Iwasaki M Jackson DJ 《Physical review letters》2003,90(14):141804
We present an improved direct measurement of the parity-violation parameter A(b) in the Z boson-b-quark coupling using a self-calibrating track-charge technique applied to a sample enriched in Z-->bb events via the topological reconstruction of the B hadron mass. Manipulation of the Stanford Linear Collider electron-beam polarization permits the measurement of A(b) to be made independently of other Z-pole coupling parameters. From the 1996-1998 sample of 400,000 hadronic Z decays, produced with an average beam polarization of 73.4%, we find A(b)=0.906+/-0.022(stat)+/-0.023(syst). 相似文献
103.
Rotor-assisted population transfer (RAPT) was developed as a method for enhancing MAS NMR sensitivity of quadrupolar nuclei by transferring polarization associated with satellite transitions to the central m=12-->-12 transition. After a single RAPT transfer, there still remains polarization in the satellite transitions that can be transferred to the central transition. This polarization is available without having to wait for the spin system to return to thermal equilibrium. We describe a new RAPT scheme that uses the remaining polarization of the satellites to obtain a further enhancement of the central transition by performing RAPT-enhanced experiments multiple times before waiting for re-equilibration of the spin system. For 27Al (I=5/2) in albite we obtain a multiple RAPT enhancement of 3.02, a 48% increase over single RAPT. For 93Nb (I=9/2) in NaNbO(3) we obtain a multiple RAPT enhancement of 5.76, an 89% increase over single RAPT. We also describe a data processing procedure for obtaining the maximum possible signal-to-noise ratio. 相似文献
104.
Sim TB Kang SH Lee KS Lee WK Yun H Dong Y Ha HJ 《The Journal of organic chemistry》2003,68(1):104-108
5-Funtionalized enantiomerically pure oxazolidin-2-ones were prepared in one pot from commercially available chiral aziridines bearing an electron-withdrawing group at C-2 with retention of the configuration in high yields by regioselective aziridine ring-opening followed by intramolecular cyclization. 相似文献
105.
Song HY Joo JM Kang JW Kim DS Jung CK Kwak HS Park JH Lee E Hong CY Jeong S Jeon K Park JH 《The Journal of organic chemistry》2003,68(21):8080-8087
The proposed structure of lasonolide A was synthesized employing radical cyclization reactions of beta-alkoxyacrylates for preparation of the tetrahydropyranyl units A and B, but the spectroscopic data did not match those of the natural product. Both enantiomers of a revised structure featuring 17E,25Z double bonds were synthesized, and the (-)-isomer was found to be the biologically active enantiomer. 相似文献
106.
Cho YS Karupaiyan K Kang HJ Pae AN Cha JH Koh HY Chang MH 《Chemical communications (Cambridge, England)》2003,(18):2346-2347
Synthesis of novel substituted tetrahydropyrans with adjacent exo-methylene groups at the C3 and C4 positions via Prins-type cyclization has been described. 相似文献
107.
It is shown that all Banach space operators which have Fourier
type p(1 < p 2) with respect to a second countable
locally compact abelian group G also have
Fourier type p with
respect to every closed discrete subgroup H
of G. The same
statement holds for any closed subgroup H
of G when p = 2.
Also shown as a corollary is that Fourier type 2 operators have
Walsh type 2.
Received: 10 June 2002 相似文献
108.
De Corte F van Sluijs R Simonits A Kucera J Smodis B Byrne AR De Wispelaere A Bossus D Frána J Horák Z Jaćimović R 《Fresenius' Journal of Analytical Chemistry》2001,370(1):38-41
After installation and calibration of k0-assisted NAA in three Central European research institutes (AEKI-Budapest, NPI-Rez, and IJS, Ljubljana), its validation was established via the analysis of three BCR certified reference materials. The matrices of choice were: CRM 277 estuarine sediment, CRM 038 coal fly ash from pulverized coal, and CRM 101 spruce needles. For some elements, e.g. Zn, Cd, and Hg, the analyses were not only performed instrumentally (INAA), but also in the radiochemical mode (RNAA). The work was performed in the framework of a European Copernicus Project. 相似文献
109.
Double-quantum and double-quantum-filtered satellite-transition magic-angle spinning (STMAS) experiments are proposed. The experiments efficiently convert satellite-transition coherence from single- to double-quantum with a central-transition selective pi-pulse. The conversion allows the selection of double-quantum coherence transfer pathways with phase cycling that completely filters out unwanted diagonal and outer satellite-transition peaks. Both experiments are demonstrated with RbNO3 and AlPO4-berlinite as model compounds for obtaining clean STMAS spectra of spins 3/2 and 5/2, respectively. 相似文献
110.
A lecture hall partition of length n is an integer sequence
satisfying
Bousquet-Mélou and Eriksson showed that the number of lecture hall partitions of length n of a positive integer N whose alternating sum is k equals the number of partitions of N into k odd parts less than 2n. We prove the fact by a natural combinatorial bijection. This bijection, though defined differently, is essentially the same as one of the bijections found by Bousquet-Mélou and Eriksson. 相似文献