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91.
R Grassi O Catalano L Romano A Pinto S Giovine A Rotondo 《Canadian Metallurgical Quarterly》1996,92(3):229-235
OBJECTIVES: The objective of this study was to estimate incidence rates for breast cancer, the most commonly occurring cancer in women, in the growing Hispanic population of Connecticut. METHODS: The population-based Connecticut Tumor Registry (CTR) routinely obtains only limited information on Hispanic origin and maiden name. In this study, surnames of CTR breast cancer patients diagnosed in 1989-1991 were matched with a list of Spanish surnames. To assess misclassification, both surnames and maiden names (from death certificates) of female Connecticut residents who had died in 1989-1991 from any cause of death at 20 years of age and older were matched with the Spanish-surname list. RESULTS: Age-specific incidence rates (1989-1991) for 'Hispanic' women (with Spanish surname) were lower than those for 'non-Hispanic' white women (with non-Spanish surname) for age 35-39 years and older. Errors in these estimated rates were probably small because among decedents the number with a Spanish surname differed by only 9% from the number with a Spanish maiden name; false positives were almost balanced by false negatives. CONCLUSION: Matching of surnames in the cancer registry with a Spanish surname list provided reasonably accurate estimates of cancer incidence rates in Hispanic women, although individual women were misclassified as 'Hispanic' or 'non-Hispanic'. 相似文献
92.
93.
Laura Gozzelino Bruno Minetti Roberto Gerbaldo Gianluca Ghigo Francesco Laviano Giuseppina Lopardo Carmen Plapcianu Angelo Agostino Stefano Cagliero Marco Truccato Luca Zilberti Enrica Mezzetti 《Journal of Superconductivity and Novel Magnetism》2011,24(1-2):307-312
Magnetic shielding properties of MgB2 bulk samples synthesized by the SPS (Spark?CPlasma?CSintering) technique were characterized in low applied magnetic fields at temperatures ranging from 20 to 37 K. The used growth technique allows one to produce this compound in different shapes and sizes required for shielding applications. In this framework, shielding magnetic-induction field profiles generated by MgB2-based shield components, shaped as planar thick disks, were measured by means of a suitable Hall probe in-plane array. The magnetic field distribution at different vertical distances above the sample was also obtained by a micrometric motion of the probe ensemble. Magnetic field profiles were then analyzed in the framework of the critical state model and the critical current density, J c , was evaluated. The J c magnitude indicates that the material under test is a good candidate for passive magnetic shield manufacturing up to temperatures close to the transition one. 相似文献
94.
Russier J Ménard-Moyon C Venturelli E Gravel E Marcolongo G Meneghetti M Doris E Bianco A 《Nanoscale》2011,3(3):893-896
In this study we compare the biodegradation of both single-walled (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) using two different oxidative conditions. In particular, we demonstrate that oxidized multi-walled carbon nanotubes are highly degraded, although not to completeness when treated with horseradish peroxidase (HRP) in the presence of hydrogen peroxide. 相似文献
95.
Several milk components related to immune defences (lysozyme, lactoferrin and gamma-globulins, gamma-G) and to inflammation (somatic cell counts, SCC; N-acetyl-beta-glucosaminidase, NAGase; albumin) were considered. Forty-one quarters and 685 samples of 24 cows were included in the study; among them 534 samples were defined as negative (78.0%), 93 as diseased (13.5%) and 58 (8.5%) as subclinical. The pattern of each milk component in quarters always negative during the follow-up period was evaluated by a mixed model. Statistical analysis showed that days in milk (DIM), age (primiparous, pluriparous), herd and the interaction between herd and days in milk significantly influenced all the markers, with very few exceptions. A subset of samples including the negative quarters before the first outcome of an infection or a subclinical mastitis and the samples from quarters always negative was also selected. The analysis showed that herd, DIM and health status had a significant influence on most markers. Overall, primiparous cows were confirmed to have higher levels of most of the markers than pluriparous cows. The presence of a herd effect on non specific immune defences in fully negative quarters implies that when the mechanisms behind their release are fully elucidated, it might be possible to modulate them. Udder tissues were confirmed as an important source of some immune components, as supported by the inconsistency between SCC mean values and NAGase, lysozyme and lactoferrin values. Overall, quarters with high levels of NAGase, lysozyme and gamma-G, exposed to bacteria, did not develop subclinical mastitis. Hence, invading pathogens could induce the development of subclinical IMI when these components and gammaG are in low concentration. 相似文献
96.
Chiara Vitale-Brovarone Francesco Baino Francesca Tallia Cristina Gervasio Enrica Verné 《Journal of materials science. Materials in medicine》2012,23(10):2369-2380
In this work, the use of foam-like glass–ceramic scaffolds as trabecular coatings on ceramic prosthetic devices to enhance implant osteointegration is proposed. The feasibility of this innovative device was explored in a simplified, flat geometry: glass–ceramic scaffolds, prepared by polymeric sponge replication and mimicking the trabecular architecture of cancellous bone, were joined to alumina square substrates by a dense glass coating (interlayer). The role played by different formulations of starting glasses was examined, with particular care to the effect on the mechanical properties and bioactivity of the final coating. Microindentations at the coating/substrate interface and tensile tests were performed to evaluate the bonding strength between the sample’s components. In vitro bioactive behaviour was assessed by soaking in simulated body fluid and evaluating the apatite formation on the surface and inside the pores of the trabecular coating. The concepts disclosed in the present study can have a significant impact in the field of implantable devices, suggesting a valuable alternative to traditional, often invasive bone-prosthesis fixation. 相似文献
97.
Giuseppe Pepe Enrica Calce Valentina Verdoliva Michele Saviano Vittorio Maglione Alba Di Pardo Stefania De Luca 《International journal of molecular sciences》2020,21(22)
Identification of molecules able to promote neuroprotective mechanisms can represent a promising therapeutic approach to neurodegenerative disorders including Huntington’s disease. Curcumin is an antioxidant and neuroprotective agent, even though its efficacy is limited by its poor absorption, rapid metabolism, systemic elimination, and limited blood–brain barrier (BBB) permeability. Herein, we report on novel biodegradable curcumin-containing nanoparticles to favor the compound delivery and potentially enhance its brain bioavailability. The prepared hyaluronan-based materials able to self-assemble in stable spherical nanoparticles, consist of natural fatty acids chemically conjugated to the natural polysaccharide. The aim of this study is to provide a possible effective delivery system for curcumin with the expectation that, after having released the drug at the specific site, the biopolymer can degrade to nontoxic fragments before renal excretion, since all the starting materials are provided by natural resource. Our findings demonstrate that curcumin-encapsulated nanoparticles enter the cells and reduce their susceptibility to apoptosis in an in vitro model of Huntington’s disease. 相似文献
98.
Luca Maria Chiesa Emanuela Zanardi Maria Nobile Enrica Ferretti Sergio Ghidini 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(5):779-788
Monitoring environmental contaminants in edible animal species is important for the assessment of environmental quality and for food safety as well. In this study, the occurrence of 2,3,7,8 dioxins, and furans, dioxin-like polychlorinated biphenyls, six non-dioxin-like polychlorinated biphenyl indicators (ndl-PCBs), seven polybrominated diphenylethers (PBDEs), four polycyclic aromatic hydrocarbons (PAHs) and four metals (As, Hg, Ni, Pb) was evaluated in 90 European eels (Anguilla anguilla) from Lake Garda. The results on eel samples showed a frequent contamination of dl-PCBs, found at concentrations higher than the maximum limit (ML) provided by European Union in 41 % of the eels. Two PBDE congeners (BDE 47 and BDE 99) were detected in almost all the samples. The contamination by PAHs was found negligible; only one sample had a high concentration of benzo[a]pyrene. Concerning metals, Pb showed concentrations higher than the maximum level (ML) in 77% of the samples, while Ni content could be a cause of acute toxicity due to dermatitis. Extreme consumers (95th percentile) are subjected to an actual risk attributable to dioxins, furans, and mainly dl-PCBs and PBDEs. The contamination of Lake Garda eels is therefore a matter of concern and a constant monitoring of the pollution levels of its freshwater is mandatory. 相似文献
99.
Francesco Baino Enrica Verné Elisa Fiume Oscar Peitl Edgar D. Zanotto Simone M. Brandão Silvana A. Schellini 《International Journal of Applied Ceramic Technology》2019,16(5):1850-1863
This review focuses on the applications of bioactive glasses and glass-ceramics in the field of orbital implants for ocular surgery. This use is relatively novel and less popular compared to the applications in orthopedics and dentistry for the repair of bone and teeth. Recent studies have shown the suitability of bioactive glasses and glass-ceramics in contact with soft tissues for promoting additional effects associated to the release of therapeutic inorganic ions. Specifically, the angiogenic and antibacterial actions that may be elicited by selected glass compositions are highly appealing for the development of new-generation orbital implants, since improved vascularization and antiseptic properties are the key for a higher success rate of anophthalmic socket procedures. An overall picture of existing orbital implants based on bioactive glasses is here provided, and the further potential and open challenges for future research in this field are highlighted and discussed. 相似文献
100.
Ivet Ferrer Marianna Garfí Enrica Uggetti Laia Ferrer-MartíEnric Velo 《Biomass & bioenergy》2011,35(5):1668-1674
Low-cost tubular digesters originally developed in tropical regions have been adapted to the extreme weather conditions of the Andean Plateau (3000-4000 m.a.s.l.). The aim of this study was to characterise biogas production in household digesters located at high altitude, operating under psychrophilic conditions. To this end, two pilot digesters were monitored and field campaigns were carried out in two representative digesters of rural communities. Digesters’ useful volume ranged between 2.4 and 7.5 m3, and hydraulic residence time (HRT) between 60 and 90 days. The temperature inside the digester’s greenhouse ranged between 20 and 25 °C. Treating cow manure, a specific biogas production around 0.35 m3 kgVS−1 was obtained, with some 65% CH4 in biogas. In order to fulfil daily requirements for cooking and lighting, biogas production should be enhanced without increasing implementation costs as not to impede the expansion of this technology at household scale. In this sense, HRT below 60 days and OLR above 1 kgVS m−3 day−1 should be investigated to decrease digesters’ volume (i.e. costs) and increase biogas production rate. The adaptation of conventional gas burners to biogas characteristics can also contribute in improving the efficiency of the system. 相似文献