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101.
    
Trabectedin is used for the treatment of advanced soft tissue sarcomas (STSs). In this study, we evaluated if trabectedin could enhance the efficacy of irradiation (IR) by increasing the intrinsic cell radiosensitivity and modulating tumor micro-environment in fibrosarcoma (HS 93.T), leiomyosarcoma (HS5.T), liposarcoma (SW872), and rhabdomyosarcoma (RD) cell lines. A significant reduction in cell surviving fraction (SF) following trabectedin + IR compared to IR alone was observed in liposarcoma and leiomyosarcoma (enhancement ratio at 50%, ER50: 1.45 and 2.35, respectively), whereas an additive effect was shown in rhabdomyosarcoma and fibrosarcoma. Invasive cells’ fraction significantly decreased following trabectedin ± IR compared to IR alone. Differences in cell cycle distribution were observed in leiomyosarcoma and rhabdomyosarcoma treated with trabectedin + IR. In all STS lines, trabectedin + IR resulted in a significantly higher number of γ-H2AX (histone H2AX) foci 30 min compared to the control, trabectedin, or IR alone. Expression of ATM, RAD50, Ang-2, VEGF, and PD-L1 was not significantly altered following trabectedin + IR. In conclusion, trabectedin radiosensitizes STS cells by affecting SF (particularly in leiomyosarcoma and liposarcoma), invasiveness, cell cycle distribution, and γ-H2AX foci formation. Conversely, no synergistic effect was observed on DNA damage repair, neoangiogenesis, and immune system.  相似文献   
102.
    
The pandemic emergency determined by the spreading worldwide of the SARS-CoV-2 virus has focused the scientific and economic efforts of the pharmaceutical industry and governments on the possibility to fight the virus by genetic immunization. The genetic material must be delivered inside the cells by means of vectors. Due to the risk of adverse or immunogenic reaction or replication connected with the more efficient viral vectors, non-viral vectors are in many cases considered as a preferred strategy for gene delivery into eukaryotic cells. This paper is devoted to the evaluation of the gene delivery ability of new synthesized gemini bis-pyridinium surfactants with six methylene spacers, both hydrogenated and fluorinated, in comparison with compounds with spacers of different lengths, previously studied. Results from MTT proliferation assay, electrophoresis mobility shift assay (EMSA), transient transfection assay tests and atomic force microscopy (AFM) imaging confirm that pyridinium gemini surfactants could be a valuable tool for gene delivery purposes, but their performance is highly dependent on the spacer length and strictly related to their structure in solution. All the fluorinated compounds are unable to transfect RD-4 cells, if used alone, but they are all able to deliver a plasmid carrying an enhanced green fluorescent protein (EGFP) expression cassette, when co-formulated with 1,2-dioleyl-sn-glycero-3-phosphoethanolamine (DOPE) in a 1:2 ratio. The fluorinated compounds with spacers formed by six (FGP6) and eight carbon atoms (FGP8) give rise to a very interesting gene delivery activity, greater to that of the commercial reagent, when formulated with DOPE. The hydrogenated compound GP16_6 is unable to sufficiently compact the DNA, as shown by AFM images.  相似文献   
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This article investigates the impact of sulfur dioxide attack, deposition of dark particles in urban environments and laser cleaning with Nd:YAG 1064 nm on color change in a range of ornamental limestones. We have used the CIELAB and CIELCH systems to compare the relative importance of the variation of each coordinate for the color change. Sulfur dioxide and dark particle deposition seems to increase the chroma, most particularly in the yellow component. Particle deposition also leads to an obvious darkening of stone surfaces. Laser irradiation at 1064 nm affects the red component of limestone, particularly if they already possess a reddish color. In general, the more intense the original color of the stone the greater are the chromatic changes, but the direction change of the color‐parameter affected by a particular process remains the same. It has always been apparent in an atmosphere heavily polluted with soot that the main changes to light‐colored stones are the exponential decrease in the parameter L* (darkening–blackening). This has important aesthetic and social implications. However, in the near future it may be that in cleaner atmospheres, perhaps more dominated by organic pollutants, a yellowing process may be of greater concern. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 320–331, 2007  相似文献   
104.
This paper is a first attempt at modelling the long-term dynamicsof market structure and innovation in the pharmaceutical industryin a history-friendly way. The model examines the relationshipsbetween the nature of the search space, demand, the patternsof competition, and industry evolution in the age of randomscreening and in the age of molecular biology, and shows thatconcentration in the pharmaceutical industry is shaped by lackof cumulativeness in innovative activities and market fragmentation.The model conforms to our appreciative understanding and respondsto changes in parameters concerning demand, costs, economiesof scale, opportunity conditions and the relative advantagesof new biotechnology firms (NBFs) vis-à-vis incumbents.With the exception of cost increases, the model is quite robustto these changes in its essential features: it is quite difficultto raise substantially concentration and to have NBFs displacingincumbents.  相似文献   
105.
Summary The essential oil obtained by steam distillation of the leaves and flowers ofArtemisia vallesiaca All., a plant widely employed in the liqueur making industry and of almost completely unknown chemical composition, after separation on a silica gel column, was investigated by means of GLC, IR and mass spectrometry. Camphene, 1,8-cineole, camphor and borneol accounted for 67–68% of the oil. Over one hundred minor compounds were found by capillary gas chromatography and 52 were identified (Table 1).
Die flüchtigen Aromastoffe von Artemisia vallesiaca All. (Berg-Genippi)
Zusammenfassung Das ätherische Öl — erhalten durch Wasserdampfdistillation aus Blättern und Blüten derArtemisia vallesiaca All., einer Pflanze, die in der Wermut-und Likörproduktion viel verwendet wird, aber chemisch fast unbekannt ist — wurde nach Säulenchromatographie an Kieselgel analysiert mittels GLC, IR und GLC-MS. Camphen, 1,8-Cineol, Campher und Borneol bilden 67–68% des ätherischen Öl. Mehr als 100 weitere Bestandteile wurden durch GLC gefunden und 52 von diesen wurden identifiziert (Tabelle 1).
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106.
Microwave power module for space applications   总被引:1,自引:0,他引:1  
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107.
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109.
A solution of heat‐denatured whey proteins was prepared by heating 100 g kg−1 whey protein isolate (WPI) at pH 7.0 to 75 °C for 15 min in the absence of salt. Heat treatment caused the globular protein molecules to unfold, but electrostatic repulsion opposed strong protein–protein aggregation and so prevented gel formation. When the heat‐denatured whey protein solution was cooled to room temperature and mixed with 15 mM CaCl2, it formed a gel. We investigated the influence of the presence of sucrose in the protein solutions prior to CaCl2 addition on the gelation rate. At relatively low concentrations (0–100 g kg−1), sucrose decreased the gelation rate, presumably because sucrose increased the aqueous phase viscosity. At higher concentrations (100–300 g kg−1), sucrose decreased the gelation rate, probably because sugar competes for the water of hydration and therefore increases the attraction between proteins. These data have important implications for the application of cold‐setting WPI ingredients in sweetened food products such as desserts. © 2000 Society of Chemical Industry  相似文献   
110.
Graph-based semi-supervised classification depends on a well-structured graph. However, it is difficult to construct a graph that faithfully reflects the underlying structure of data distribution, especially for data with a high dimensional representation. In this paper, we focus on graph construction and propose a novel method called semi-supervised ensemble classification in subspaces, SSEC in short. Unlike traditional methods that execute graph-based semi-supervised classification in the original space, SSEC performs semi-supervised linear classification in subspaces. More specifically, SSEC first divides the original feature space into several disjoint feature subspaces. Then, it constructs a neighborhood graph in each subspace, and trains a semi-supervised linear classifier on this graph, which will serve as the base classifier in an ensemble. Finally, SSEC combines the obtained base classifiers into an ensemble classifier using the majority-voting rule. Experimental results on facial images classification show that SSEC not only has higher classification accuracy than the competitive methods, but also can be effective in a wide range of values of input parameters.  相似文献   
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