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791.
Alessandra Mascaro Massimo Farina Raffaella Gigli Carlo E Vitelli Lucio Fortunato 《World journal of surgical oncology》2010,8(1):1-17
A tremendous improvement in every aspect of breast cancer management has occurred in the last two decades. Surgeons, once solely interested in the extipartion of the primary tumor, are now faced with the need to incorporate a great deal of information, and to manage increasingly complex tasks. As a comprehensive assessment of all aspects of breast cancer care is beyond the scope of the present paper, the current review will point out some of these innovations, evidence some controversies, and stress the need for the surgeon to specialize in the various aspects of treatment and to be integrated into the multisciplinary breast unit team. 相似文献
792.
A re-investigation of Pistacia vera from southern Italy afforded, in addition to known compounds, two new monoterpenes (+)-9,10-cyclopropylterpine- 相似文献
793.
794.
Arne Traulsen Jorge M. Pacheco Lucio Luzzatto David Dingli 《BioEssays : news and reviews in molecular, cellular and developmental biology》2010,32(11):1003-1008
Clonal disease is often regarded as almost synonymous with cancer. However, it is becoming increasingly clear that our bodies harbor numerous mutant clones that are not tumors, and mostly give rise to no disease at all. Here we discuss three somatic mutations arising within the hematopoietic system: BCR‐ABL, characteristic of chronic myeloid leukemia; mutations of the PIG‐A gene, characteristic of paroxysmal nocturnal hemoglobinuria; the V617F mutation in the JAK2 gene, characteristic of myeloproliferative diseases. The population frequencies of these three blood disorders fit well with a hierarchical model of hematopoiesis. The fate of any mutant clone will depend on the target cell and on the fitness advantage, if any, that the mutation confers on the cell. In general, we can expect that only a mutation in a hematopoietic stem cell will give long‐term disease; the same mutation taking place in a cell located more downstream may produce just a ripple in the hematopoietic ocean. 相似文献
795.
Alberto M. Martell Luca M. Neri Loris Zamai Renat Bareggi Lucia Manzoli Lucio Cocco 《The Histochemical journal》1994,26(2):179-188
Summary Isolated nuclei and nuclear matrices, prepared from mouse erythroleukaemia cells, were reacted with the sulphhydryl-specific dye 6-iodoacetamidofluorescein. To determine whether in vitro formation of disulphide bonds might play a role in the nuclear matrix stabilization triggered by exposure of isolated nuclei to the physiological temperature of 37°C, a variety of techniques were employed to assess the state of cysteinyl residues after such an incubation. Both flow cytometry and confocal microscopy quantitative analysis did not reveal major differences in the fluorescence intensity of nuclei incubated at 37°C in comparison with those maintained at 0°C. Confocal scanning laser microscopy revealed that 6-iodoacetamidofluorescein labelled a fibrogranular network in isolated nuclei. The fluorescent pattern of the network was not affected by a 37°C exposure of nuclei. However, such a network was not detectable in isolated nuclear matrices, thus suggesting a possible protein re-arrangement during matrix preparation. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of fluorescent-labelled nuclear proteins showed no difference between heat-exposed and control samples. We conclude that oxidation of cysteinyl residues is not a major factor leading to the stabilization of nuclei incubated at 37°C. 相似文献
796.
797.
María Teresa Blanco Beatriz Sacristán Leopoldo Lucio Javier Blanco Ciro Pérez-Giraldo Antonio Cándido Gómez-García 《Revista iberoamericana de micología》2010,27(4):195-199
ObjectiveTo evaluate virulence factors involved in the adhesion process, such as cell surface hydrophobicity (CSH), adherence to plastic capacity, adherence capacity to buccal epithelial cells (BEC), and biofilm formation, in 17 strains of C. albicans isolated from bronchial aspirates of critically ill patients.MethodThe CSH of the strains of C. albicans was determined using the MATH method, a microbial adhesion to hydrocarbons test. The study of adherence to plastic was performed in microtitre plates in accordance with Christensen's technique. Biofilm formation was studied in polystyrene microtitre plates, according to the method of Ramage. Adherence to BEC was evaluated by quantifying the percentage of adhered yeasts to cells.ResultsAll the strains studied showed factors directly involved in adhesion, with variability in the degree of expression among them. Medium-high levels of CSH were found in 52.9% of the strains. The percentage of strains with high values in adherence to plastic was 35.3%. The most hydrophobic strains were the most adherent to plastic, with a correlation coefficient of 0.76. Of the 12 biofilm-producing strains, 6 were high producers. These strains had also high levels of CSH and adherence to plastic, with significant results. All the strains studied adhered to BEC, with results ranging widely from 45 to 157 yeasts/100 BEC, with no significant correlation with the rest of the parameters studied, although CSH was seen to be an indispensable prior requisite for adherence to cells.ConclusionCSH is a variable characteristic in C. albicans and is directly related to adherence to plastic and biofilm formation. Ease in evaluating CSH permits its quantification, and could be used as an indicator of the presence of other determinants of pathogenicity. 相似文献
798.
Lucio Cocco Silvia Rubbini Lucia Manzoli Anna Maria Billi Irene Faenza Daniela Peruzzi Alessandro Matteucci Marco Artico R.Stewart Gilmour Sue Goo Rhee 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》1999,1438(2):295-299
Previous reports from our laboratories and others have hinted that the nucleus is a site for an autonomous signalling system acting through the activation of the inositol lipid cycle. Among phospholipases (PLC) it has been shown previously that PLCβ1 is specifically localised in the nucleus as well as at the plasma membrane. Using NIH 3T3 cells, it has been possible to obtain, with two purification strategies, in the presence or in the absence of Nonidet P-40, both intact nuclei still maintaining the outer membrane and nuclei completely stripped of their envelope. In these nuclei, we show that not only PLCβ1 is present, but also PLCβ2, PLCβ3 and PLCβ4. The more abounding isoform is PLCβ1 followed by PLCβ3, PLCβ2 and PLCβ4, respectively. All the isoforms are enriched in nuclear preparations free from nuclear envelope and cytoplasmatic debris, indicating that the actual localisation of the PLCβ isozymes is in the inner nuclear compartment. 相似文献
799.
800.
Stefania Fioravanti Simona Gasbarri Alberto Morreale Lucio Pellacani Federico Ramadori Paolo A. Tardella 《Amino acids》2010,39(2):461-470
Non-symmetric disubstituted malonamides rAA-mGly-AA′, obtained from Meldrum’s acid, were considered as methylene active compounds and a Knoevenagel condensation methodology was developed involving piperidine and activated 4 Å molecular sieves as catalysts. The reaction is efficient, broad in scope, and easy to perform and allows access to E/Z mixtures of short malonyl dehydro peptides (MDHPs) rAA-mΔ2AA″-AA′, partially modified retro peptides characterized by an interesting combination of retro and dehydro modifications in the same structure. 相似文献