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491.
492.
The cure rate of germ cell tumours (GCTs) has significantly increased from the late 1970s since the introduction of cisplatin-based therapy, which to date remains the milestone for GCTs treatment. The exquisite cisplatin sensitivity has been mainly explained by the over-expression in GCTs of wild-type TP53 protein and the lack of TP53 somatic mutations; however, several other mechanisms seem to be involved, many of which remain still elusive. The findings about the role of TP53 in platinum-sensitivity and resistance, as well as the reported evidence of second cancers (SCs) in GCT patients treated only with surgery, suggesting a spectrum of cancer predisposing syndromes, highlight the need for a deepened understanding of the role of TP53 in GCTs. In the following report we explore the complex role of TP53 in GCTs cisplatin-sensitivity and resistance mechanisms, passing through several recent genomic studies, as well as its role in GCT patients with SCs, going through our experience of Center of reference for both GCTs and cancer predisposing syndromes.  相似文献   
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The authors have recently demonstrated the enhancement of the quantum dot laser modal gain, linearly scaling with the number of stacked QD layers. These results allowed the achievement of multi-quantum dot (MQD) lasers, the zero-dimensional counterpart of MQW lasers, with a modal gain as high as 42?cm(-1), in a seven-layer structure. A detailed investigation of the structural and optical properties was performed on laser structures with three, five and seven QD layers. Such an investigation clearly shows that the high uniformity of QD layer features is responsible for the linear increase of the modal gain and its high value.  相似文献   
495.
Enterococcus faecium strains were isolated from red wines undergoing malolactic fermentation and identified by comparison of their 16S rDNA gene sequences with those included in the GenEMBL Databases. The tyrosine decarboxylase gene was identified in all the strains analysed by PCR using gene-specific primers and the ability to produce tyramine in a synthetic media was analysed by RP-HPLC. Survival of an E. faecium strain was also evaluated in microvinification assays using two different musts with different ethanol concentrations (10% and 12% (v/v)). Tyramine production was monitored during the vinification trials. Our results suggest that E. faecium strains isolated from wine are able to produce tyramine and tolerate wine conditions following a pre-acidic stress.  相似文献   
496.
In this work, the effect of active coating on the shelf life of low-moisture Mozzarella cheese packaged in air and modified atmosphere (MAP) was studied. The active coating was based on sodium alginate (2%, wt/vol) and potassium sorbate (1%, wt/vol). The MAP was made up of 75% CO2 and 25% N2 (MAP1), 25% CO2 and 75% N2 (MAP2), or 50% CO2 and 50% N2 (MAP3). The product quality decay was assessed by monitoring microbiological and sensory changes during storage at 4, 8, and 14°C. Results showed that the combination of active coating and MAP was able to improve the preservation of low-moisture Mozzarella cheese. Specifically, the shelf life increased up to 160 d for samples stored at 4°C, and 40 and 11 d for those at 8 and 14°C, respectively. A faster quality decay for untreated samples packaged in air was observed. In particular, the Pseudomonas spp. growth and the appearance of molds were responsible for product unacceptability. The combination of active coating and MAP represents a strategic solution to prolong the shelf life of low-moisture Mozzarella cheese and to ensure the safety of the product under thermal abuse conditions.  相似文献   
497.
In this paper the results of experimental tests in a boundary layer wind tunnel aimed at direct comparison of the two main methods used to estimate the wind loads acting on tall buildings are presented. The tests were performed on two different models of tall buildings: a regular one with a prismatic shape; an irregular one whose external shape was inspired by that of Bank of China Tower in Hong Kong. The two models have the same square footprint and height. The two methods used to measure the wind effects were: the high frequency force balance, which allows to directly measure the global base reactions (two forces in the plane of the base, the two overturning moments and the torsional moment around the vertical axis); the synchronous multi-pressure sensing system, which measures the pressure in several points on the surface of the model, and allows, by means of numerical integration, to estimate both the floor loads and the base reactions. In order to perform a comparison between the results obtained by the high frequency force balance and synchronous multi-pressure sensing system a statistical analysis of the results was carried out; in particular, higher order moments were investigated. Moreover the spectra and the correlation structure of the loads were studied.  相似文献   
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499.
With the objective of creating an electro-responsive and antimicrobial device suitable as delivery system for Rose Bengal (RB) to the skin, a hybrid hydrogel combining Chitosan (CS) and Graphene Oxide (GO) are designed, serving as functional polymer support and active filling element, respectively. The hybrid system, synthesized using tripolyphosphate as a crosslinker via ionic gelation, shows a uniform and homogeneous surface, as verified by SEM investigations, high biocompatibility when tested on human fibroblast lung cells MRC-5 cells, and biodegradability in phosphate buffered medium at physiological pH. Drug loading and release experiments, extensively analyzed using suitable mathematical modeling, shows the enhancement of the binding efficiency conferred by GO (534 and 979 mg g−1 for blank and hybrid hydrogels, respectively) and an electro-responsive behavior (maximum BR release of 36 and 23% at 0 and 12 V, respectively). Additionally, hybrid hydrogel is found to prevent the adhesion of methicillin-resistant Staphylococcus aureus and to kill the bacterial cells by taking advantage of the sustained release of the antimicrobial RB.  相似文献   
500.
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