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101.
Velasco E Infante M Durán M Esteban-Cardeñosa E Lastra E García-Girón C Miner C 《Electrophoresis》2005,26(13):2539-2552
Mutational analysis of large multiexon genes without prevalent mutations is a laborious undertaking that requires the use of a high-throughput scanning technique. The Human Genome Project has enabled the development of powerful techniques for mutation detection in large multiexon genes. We have transferred heteroduplex analysis (HA) by conformation-sensitive gel electrophoresis of the two major breast cancer (BC) predisposing genes, BRCA1 and BRCA2, to a multicapillary DNA sequencer in order to increase the throughput of this technique. This new method that we have called heteroduplex analysis by capillary array electrophoresis (HA-CAE) is based on the use of multiplex-polymerase chain reaction (PCR), different fluorescent labels and HA in a 16-capillary DNA sequencer. To date, a total of 114 different DNA sequence variants (19 insertions/deletions and 95 single-nucleotide substitutions - SNS) of BRCA1 and BRCA2 from 431 unrelated BC families have been successfully detected by HA-CAE. In addition, we have optimized the multiplex-PCR conditions for the colorectal cancer genes MLH1 and MSH2 in order to analyze them by HA-CAE. Both genes have been amplified in 13 multiplex groups, which contain the 35 exons, and their corresponding flanking intronic sequences. MLH1 and MSH2 have been analyzed in nine hereditary nonpolyposis colorectal cancer patients, and we have found six different DNA changes: one complex deletion/insertion mutation in MLH1 exon 19 and another five SNS. Only the complex mutation and one SNS may be classified as cancer-prone mutations. Our experience has revealed that HA-CAE is a simple, fast, reproducible and sensitive method to scan the sequences of complex genes. 相似文献
102.
Y.?CastroEmail author B.?Ferrari R.?Moreno A.?Durán 《Journal of Sol-Gel Science and Technology》2005,35(1):51-55
SiO2-ZrO2 sols have been prepared via acid catalysis using a commercial colloidal suspension of zirconia and two silica alkoxides; tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES). Suspensions with 10, 15 and 25-mol% of ZrO2 were prepared. The stability of the suspensions was followed by rheological measurements showing that the amount of water incorporated with the colloidal suspension is the factor that limits the maximum ZrO2 content. Coatings have been prepared by dipping using the suspensions up to 25-mol% ZrO2 onto glass-slides at different withdrawal rates. EPD process has been used to prepare coatings onto stainless steel AISI 304 using the suspension with 25-mol% ZrO2 at different pHs. The parameters associated with the EPD process (current density, electric field, potential and deposition time) have been evaluated. The critical thickness for a ZrO2 addition of 25-mol% was 0.8 μm and it increased for diminishing ZrO2 content. 相似文献
103.
Thin-film exchangers have a large heat-transfer area per unit liquid volume that make them very efficient for industrial use. Unfortunately, they are usually less applied for education purposes. In this work, a simple experimental device with a fluid flowing as a falling film has been assembled. In addition, an experimental guide allows students to determine the individual heat-transfer coefficient in the exchanger.The experimental setup consists of two pipes bundled as a shell-and-tube heat exchanger. The cold liquid flows in the form of a thin film that runs down inside the inner tube; the hot liquid flows down concurrently in the external one.In order to test the operation of the device, experimental results are given for a simple test with water. Heat-transfer coefficients are calculated and a theoretical correlation obtained from the literature is compared with the experimental results. In addition, a fit of the data allows for the formulation of a new empirical equation for the transient regime. 相似文献
104.
105.
106.
We have applied the meson cloud model to calculate the asymmetries in D and D(s) meson production in high-energy Sigma(-)-nucleus and pi(-)-nucleus collisions. We find a good agreement with recent data. Our results suggest that the asymmetries may decrease at large x(F). 相似文献
107.
R.M. Durán Delgado G. Gustafson L. Lönnblad 《The European Physical Journal C - Particles and Fields》2007,52(1):113-119
We investigate some recent measurements of Fermi–Dirac correlations by the LEP collaborations indicating surprisingly small
source radii for the production of baryons in e+e- annihilation at the Z0 peak. In hadronization models there is besides the Fermi–Dirac correlation effect also a strong dynamical (anti-) correlation.
We demonstrate that the extraction of the pure FD effect is highly dependent on a realistic Monte Carlo event generator, both
for separation of those dynamical correlations that are not related to Fermi–Dirac statistics, and for corrections of the
data and background subtractions. Although the model can be tuned to well reproduce single particle distributions, there are
large model uncertainties when it comes to correlations between identical baryons. We therefore, unfortunately, have to conclude
that it is at present not possible to draw any firm conclusion about the source radii relevant for baryon production at LEP.
PACS 13.60.Rj; 13.66.Bc 相似文献
108.
Mariângela B. M. De Azevedo Joel Alderete Jaime A. Rodriguez Ana O. Souza Daniel Rettori Marcio A. Torsoni Adelaide Faljoni-Alario Marcela Haun Nelson Durân 《Journal of inclusion phenomena and macrocyclic chemistry》2000,37(1-4):93-101
Violacein is a poorly water-soluble antitumoraland antibacterial drug. The solubility can be enhanced by complexation with-cyclodextrin. The inclusion complex was prepared by the co-precipitation method in molarratios of 1 : 1 and 1 : 2 of violacein/-cyclodextrin, respectively. The acutetoxicity (E. coli strain) of violacein did not changeup to 400 M, either in thepresence or absence of cyclodextrin. Cytotoxicity (V-79 cellculture) through DNA and MTT assays was significantlydecreased in the presence of the 1 : 2 molar ratio complex.Studies on erythrocyte lipid peroxidation by the thiobarbituricacid (TBA) methodshowed that violacein and violacein/-CD (1 : 2) at100 M cause 50% and 80% inhibition, respectively. At 500 M theviolacein/-CD complexinhibited lipid peroxidation completely; however, withfree violacein only 65% inhibition was reached at that concentration. 相似文献
109.
We introduce a non-linear injective transformation τ from the set of non-vanishing normalized Hausdorff moment sequences to the set of normalized Stieltjes moment sequences by the formulaT[(a n ) n=1 ∞ ] n = 1/a1 ...a n . Special cases of this transformation have appeared in various papers on exponential functionals of Lévy processes, partly motivated by mathematical finance. We give several examples of moment sequences arising from the transformation and provide the corresponding measures, some of which are related toq-series. 相似文献
110.
Areces P Angeles Durán M Plumet J Hursthouse MB Light ME 《The Journal of organic chemistry》2002,67(10):3506-3509
Some N-substituted-3-azabicyclo[3.3.0]octen-7-one derivatives have been synthesized in an enantiomerically pure form starting from tri-O-acetyl-D-glucal via intramolecular Pauson-Khand (IPK) cycloaddition. 相似文献