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31.
L Bini B Magi B Marzocchi F Arcuri S Tripodi M Cintorino JC Sanchez S Frutiger G Hughes V Pallini DF Hochstrasser P Tosi 《Canadian Metallurgical Quarterly》1997,18(15):2832-2841
Reference two-dimensional (2-D) gels are presented for human breast ductal carcinoma and histologically normal tissue. Whole biopsy fragments were analyzed, including epithelial and nonepithelial components. Thirty-five spots have been assigned by gel matching to the human liver SWISS-2DPAGE reference map and/or to the human primary keratinocyte IPG map from the Danish Center for Human Genome. N-terminal microsequencing was applied to confirm randomly chosen matching assignments and to identify six new spots. Protein expression profiles in ductal carcinoma and in normal breast tissue appeared to be similar, except for a pattern consisting of 32 spots, which were highly expressed in all carcinoma specimens, and less intense and occasionally undetectable in normal tissue. This difference was statistically significant. Assignment has been obtained for several spots, namely GRP94, GRP78, GRP75, mitochondrial HSP60, calreticulin, protein disulfide isomerase, peptidyl-prolyl cis-trans isomerase, collagen-binding protein 2, fructose bisphosphate aldolase, glyceraldehyde-3-phosphate dehydrogenase, thioredoxin, cytochrome c oxidase VA subunit, tubulin beta isoform and macrophage migration inhibitory factor (MIF). The cancer- and tissue-specificity of the described pattern was assessed by matching to the Swiss-2DPAGE human liver, hepatoma, lymphoma, erythroleukemia reference maps. The pattern of 32 spots was found to be indicative of epithelial neoplasia. 相似文献
32.
33.
1. The construction of three-dimensional models of CYP2B isozymes from rat (CYP2B1), rabbit (CYP2B4) and man (CYP2B6), based on a multiple sequence alignment with CYP102, a unique eukaryotic-like bacterial P450 (in terms of possessing an NADPH-dependent FAD- and FMN-containing oxidoreductase redox partner) of known crystal structure, is reported. 2. The enzyme models described are shown to be consistent with experimental evidence from site-directed mutagenesis studies, antibody recognition sites and amino acid residues identified as being associated with redox partner interactions, together with the location of a key serine residue (Ser-128) likely to be involved in protein kinaseA-mediated phosphorylation. 3. A substantial number of known substrates and inhibitors of CYP2B isozymes are shown to fit the putative active sites of the enzyme models in agreement with their reported position of metabolism or mode of inhibition respectively. In particular, there is complementarity between the characteristic non-planar geometries of CYP2B substrates and key groups in the enzymes' active sites. 4. Molecular modelling of CYP2B isozymes appears to rationalize a number of the reported findings from quantitative structure-activity relationship investigations on series of CYP2B substrates and inhibitors. 相似文献
34.
35.
A. Ureña J. M. Gomez De Salazar J. Quiñones S. Merino J. Martin 《Journal of Materials Science》1996,31(3):807-817
Diffusion bonds have been produced between sheets of an Al-Li-Cu-Mg-Zr alloy using aluminium-4% copper vapour deposited metallic interlayers. Microstructural changes occurred both in the parent alloy and in the bond interface after diffusion bonding cycles and post-bonding heat treatments were analysed. Different metallographic techniques (light microscopy, scanning and transmission electron microscopy) have been used. Diffusion bonding trials were carried out using the same alloy (AA8090), both in non-superplastic (T6) and superplastic conditions. Differences in their behaviours in relation to diffusion bonding were observed. 相似文献
36.
RM Martín‐Aranda E Ortega‐Cantero ML Rojas‐Cervantes MA Vicente‐Rodríguez MA Baares‐Muoz 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(2):234-238
α,β‐Unsaturated nitriles have been synthesized by Knoevenagel condensation of a carbonylic compound with malononitrile, assisted by sonochemical irradiation. Two alkaline‐promoted clays (Li+‐ and Cs+‐exchanged saponites) have been employed as catalysts. The influence of the carbonylic compound (benzaldehyde or cyclohexanone) and the use of a solvent on the catalytic activity have been studied. Remarkable increase in the conversion values has been found when the reaction is activated by ultrasound, as compared with the thermal activation. In this green, solvent‐free procedure, α,β‐unsaturated nitriles have been produced in very high yields (97%) when the Cs+‐saponite is used as catalyst. Copyright © 2004 Society of Chemical Industry 相似文献
37.
This paper introduces and evaluates a new class of knowledge model, the recursive Bayesian multinet (RBMN), which encodes the joint probability distribution of a given database. RBMNs extend Bayesian networks (BNs) as well as partitional clustering systems. Briefly, a RBMN is a decision tree with component BNs at the leaves. A RBMN is learnt using a greedy, heuristic approach akin to that used by many supervised decision tree learners, but where BNs are learnt at leaves using constructive induction. A key idea is to treat expected data as real data. This allows us to complete the database and to take advantage of a closed form for the marginal likelihood of the expected complete data that factorizes into separate marginal likelihoods for each family (a node and its parents). Our approach is evaluated on synthetic and real-world databases. 相似文献
38.
V. Salgueiriño‐Maceira M. A. Correa‐Duarte 《Advanced materials (Deerfield Beach, Fla.)》2007,19(23):4131-4144
This Review article ponders core/shell structured nanoparticles that can be prepared with features that combine properties of different materials, including ligands that enhance their biocompatibility. These nanocomposites are not classified in terms of synthesis, but rather by how these features are distributed in the final morphology, attending to connected or isolated materials that end up in interacting or not‐interacting functionalities. In particular, we have focused on magnetic core/shell‐structured particles with a directly connected, coupled, or isolated second functionality. The current progress on methods in colloidal solution that have allowed the great development of these multifunctional magnetic and active spheres on biological and biomedical fields is reported. 相似文献
39.
An evaluation of the Spanish CSIC performance in Biotechnology, as compared with those of the French CNRS and the Italian
CNR, has been carried out to determine the balance between the generation of scientific knowledge and the transfer of technology.
This study shows a high scientific productivity mostly in journals with moderate impact factor, a low generation of patents
and an insufficient transfer of knowledge to the Spanish companies. Other indicators confirm the existence of competitive
human resources in biotechnological research producing scientific knowledge of interest for the development of patents and
that cooperates successfully at European level. 相似文献
40.
P. Cañizares J. García-Gómez C. Sáez M.A. Rodrigo 《Journal of Applied Electrochemistry》2003,33(10):917-927
The electrochemical oxidation of 4-chlorophenol, 2,4-dichlorophenol and 2,4,6-trichlorophenol aqueous wastes using boron-doped diamond electrodes was studied. This treatment led to complete mineralization of the wastes regardless of the operating conditions. A simple mechanistic model is consistent with the voltammetric and electrolysis results. According to this model, the electrochemical treatment of chlorophenol aqueous wastes involves the anodic and cathodic release of chlorine followed by the formation of non-chlorinated aromatic intermediates. Subsequent cleavage of the aromatic ring gives rise to non-chlorinated carboxylic acids. Chlorine atoms arising from the hydrodehalogenation of the chlorophenols are converted into more oxidized molecules at the anode. These molecules react with unsaturated C4 carboxylic acid to finally yield trichloroacetic acid through a haloform reaction. The non-chlorinated organic acids are ultimately oxidized to carbon dioxide and the trichloroacetic acid into carbon dioxide and volatile organo-chlorinated molecules. Both direct and mediated electrochemical oxidation processes are involved in the electrochemical treatment of chlorophenols. 相似文献