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排序方式: 共有2920条查询结果,搜索用时 15 毫秒
931.
Lorenzo Belluomini Alberto Caldart Alice Avancini Alessandra Dodi Ilaria Trestini Dzenete Kadrija Marco Sposito Daniela Tregnago Miriam Casali Silvia Teresa Riva Giulia Sartori Jessica Menis Michele Milella Sara Pilotto 《International journal of molecular sciences》2021,22(1)
Infectious diseases represent a relevant issue in lung cancer patients. Bacterial and viral infections might influence the patients’ prognosis, both directly affecting the immune system and indirectly impairing the outcome of anticancer treatments, mainly immunotherapy. In this analysis, we aimed to review the current evidence in order to clarify the complex correlation between infections and lung cancer. In detail, we mainly explored the potential impact on immunotherapy outcome/safety of (1) bacterial infections, with a detailed focus on antibiotics; and (2) viral infections, discriminating among (a) human immune-deficiency virus (HIV), (b) hepatitis B/C virus (HBV-HCV), and (c) Sars-Cov-2. A series of studies suggested the prognostic impact of antibiotic therapy administration, timing, and exposure ratio in patients treated with immune checkpoint inhibitors, probably through an antibiotic-related microbiota dysbiosis. Although cancer patients with HIV, HBV, and HCV were usually excluded from clinical trials evaluating immunotherapy, some retrospective and prospective trials performed in these patient subgroups reported similar results compared to those described in not-infected patients, with a favorable safety profile. Moreover, patients with thoracic cancers are particularly at risk of COVID-19 severe outcomes and mortality. Few reports speculated about the prognostic implications of anticancer therapy, including immunotherapy, in lung cancer patients with concomitant Sars-Cov-2 infection, showing, to date, inconsistent results. The correlation between infectious diseases and immunotherapy remains to be further explored and clarified in the context of dedicated trials. In clinical practice, the accurate and prompt multidisciplinary management of lung cancer patients with infections should be encouraged in order to select the best treatment options for these patients, avoiding unexpected toxicities, while maintaining the anticancer effect. 相似文献
932.
Martina Mandarano Elena Orecchini Guido Bellezza Jacopo Vannucci Vienna Ludovini Sara Baglivo Francesca Romana Tofanetti Rita Chiari Elisabetta Loreti Francesco Puma Angelo Sidoni Maria Laura Belladonna 《International journal of molecular sciences》2021,22(9)
The enzyme indoleamine 2,3-dioxygenase 1 (IDO1) degrade tryptophan (Trp) into kynurenine (Kyn) at the initial step of an enzymatic pathway affecting T cell proliferation. IDO1 is highly expressed in various cancer types and associated with poor prognosis. Nevertheless, the serum Kyn/Trp concentration ratio has been suggested as a marker of cancer-associated immune suppression. We measured Kyn and Trp in blood samples of a wide cohort of non-small-cell lung cancer (NSCLC) patients, before they underwent surgery, and analyzed possible correlations of the Kyn/Trp ratio with either IDO1 expression or clinical–pathological parameters. Low Kyn/Trp significantly correlated with low IDO1 expression and never-smoker patients; while high Kyn/Trp was significantly associated with older (≥68 years) patients, advanced tumor stage, and squamous cell carcinoma (Sqcc), rather than the adenocarcinoma (Adc) histotype. Moreover, high Kyn/Trp was associated, among the Adc group, with higher tumor stages (II and III), and, among the Sqcc group, with a high density of tumor-infiltrating lymphocytes. A trend correlating the high Kyn/Trp ratio with the probability of recurrences from NSCLC was also found. In conclusion, high serum Kyn/Trp ratio, associated with clinical and histopathological parameters, may serve as a serum biomarker to optimize risk stratification and therapy of NSCLC patients. 相似文献
933.
Giuseppe Sancataldo Sara Anselmo Valeria Vetri 《Microscopy research and technique》2020,83(7):811-816
The formation of amyloid structures has traditionally been related to human neurodegenerative pathologies and, in recent years, the interest in these highly stable nanostructures was extended to biomaterial sciences. A common method to monitor amyloid growth is the analysis of Thioflavin T fluorescence. The use of this highly selective dye, diffused worldwide, allows mechanistic studies of supramolecular assemblies also giving back important insight on the structure of these aggregates. Here we present experimental evidence of self‐quenching effect of Thioflavin T in presence of amyloid fibrils. A significant reduction of fluorescence lifetime of this dye which is not related to the properties of analyzed amyloid structures is found. This result is achieved by coupling Fluorescence Lifetime Imaging Microscopy with phasor approach as suitable model‐free methods and constitute a serious warning that have to be taken in account if is dye is used for quantitative studies. 相似文献
934.
Catia Arbizzani Sara Righi Francesca Soavi Marina Mastragostino 《International Journal of Hydrogen Energy》2011,36(8):5038-5046
Non-precious metal catalysts for the oxygen reduction reaction (ORR) in proton-exchange-membrane fuel cells (PEMFCs) were obtained by pyrolysis of iron citrate and polyacrylonitrile on mesoporous xerogel carbon support. Chemical-physical characterizations, electrochemical studies by the rotating disc electrode, and electrochemical tests in a PEMFC configuration demonstrated that the porosity of the pristine carbon promotes the formation of graphene and carbon nanotube structures featuring ORR catalytic activity. 相似文献
935.
In recent years the integration of spatial data coming from different sources has become a crucial issue for many geographical
applications, especially in the process of building and maintaining a Spatial Data Infrastructure (SDI). In such context new
methodologies are necessary in order to acquire and update spatial datasets by collecting new measurements from different
sources. The traditional approach implemented in GIS systems for updating spatial data does not usually consider the accuracy
of these data, but just replaces the old geometries with the new ones. The application of such approach in the case of an
SDI, where continuous and incremental updates occur, will lead very soon to an inconsistent spatial dataset with respect to
spatial relations and relative distances among objects. This paper addresses such problem and proposes a framework for representing
multi-accuracy spatial databases, based on a statistical representation of the objects geometry, together with a method for
the incremental and consistent update of the objects, that applies a customized version of the Kalman filter. Moreover, the
framework considers also the spatial relations among objects, since they represent a particular kind of observation that could
be derived from geometries or be observed independently in the real world. Spatial relations among objects need also to be
compared in spatial data integration and we show that they are necessary in order to obtain a correct result in merging objects
geometries. 相似文献
936.
Rosa Sara Groen 《Urban Research & Practice》2016,9(3):250-274
The Hague, Geneva and Vienna are three cities that historically grew into global centers, specialized in human rights, nonproliferation, security, and peace and justice-related topics. The aim of this paper is to compare the policy of these cities on international organizations (IOs) and international nongovernmental organizations (INGOs). These cities experience increased competition from other international cities hosting IOs and INGOs due to globalization. Therefore, the need exists to reformulate strategies in attracting and retaining IOs and INGOs. Through an intensive comparative method, this paper seeks to describe the parallels and differences between these three cities, concerning their strategies. Furthermore, it describes the current need to make use of well-coordinated lobbying strategies, policy networks and thematic policy coalitions in order to gain and retain IOs and INGOs in a successful way. 相似文献
937.
Marinella Levi Sara Cortesi Carlo Vezzoli Giuseppe Salvia 《Packaging Technology and Science》2011,24(7):387-400
Each year in Italy, millions of tons of fruits and vegetables are harvested, packed and transported to national and foreign retail outlets. Packaging is an essential component of this system, but what is its environmental impact? This study takes into consideration the delivery from the field to the retail outlet of 12 types of fruits and vegetables grown and harvested in Italy and sold in Italy and Europe. The study compares two different packaging and distribution systems: one‐way with corrugated boxes and reusable with plastic containers. A number of different scenarios were generated by combining the most diffused packaging sizes with the most important production and selling locations for each type of fruit and vegetable and by considering the specific route required to perform the transportation with each distribution system. The environmental impact of each system in each scenario has then been analysed using the life cycle assessment methodology. Two algorithms and a number of coefficients were derived to simplify data collection and impact analysis for all scenarios. This provides an easy tool to evaluate the potential environmental burden of the two alternative distribution systems in a specific scenario by taking into consideration only a few variables (such as size of packaging and transportation distance). These algorithms and coefficients are presented in the work, along with the process that led to their generation and with considerations about the main critical environmental aspects for both distribution systems. The work aims to suggest possible design solutions that can make each system more sustainable. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
938.
Giuliana Ferrero Hector Monclús Gianluigi Buttiglieri Sara Gabarron Joaquim Comas Ignasi Rodríguez‐Roda 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(6):784-789
BACKGROUND: Membrane bioreactors are used in an increasing number of wastewater treatment facilities because of their compactness and efficiency in solid‐liquid separation, but energy requirements are still higher than other competitive technologies such as conventional activated sludge. RESULTS: In this paper the development of an air‐scour control algorithm based on short‐term and long‐term membrane permeability evolution is presented. An open loop calibration and partial validation was carried out in a semi‐industrial scale pilot plant where manual changes in air‐scour flow had been previously carried out. The control system was successfully tested in closed loop in an industrial scale pilot plant, defining a maximum daily air‐scour decrease or increase of 6% of the air‐scour recommended by membranes suppliers. An average air‐scour saving of 13% and a maximum of 20%, calculated in terms of air flow saved, were achieved during the validation test without any apparent long‐term effect on membrane permeability. CONCLUSION: It was proven that the air‐scour control system is an important tool capable of reducing operational costs in MBR systems. Copyright © 2011 Society of Chemical Industry 相似文献
939.
Using digital image correlation, we track the displacement fluctuations within a persistent shear band in a dense sand specimen bounded by glass walls undergoing plane strain compression. The data evidences a clear, systematic, temporally recurring pattern of vortex formation, dissolution, and reformation throughout macroscopic softening and critical state regimes. During softening, locally affine deformation zones are observed at various locations along the shear band, which we argue to be kinematic signatures of semi-stable force chains. Force chain collapse then occurs, inducing vortex formation. Local jamming at the conflux of opposing displacements between adjacent vortices arrests the vortices, providing an avenue for potential new force chains to form amidst these jammed regions. The process repeats itself temporally throughout the critical state. The pattern further correlates with fluctuations in macroscopic shear stress. We characterize the nature of the observed vortices, as they are different in our sands comprised of irregular shaped particles, as compared to previous observations from experiments and numerical simulations which involved circular or rounded particles. The results provide an interesting benchmark for behavior of non-circular/non-spherical particles undergoing shear. 相似文献
940.
Lee Jihye Moon Sangmi Kwon Soonho Chu Myeonghun Bae Sara You Cheolwoo Liu Huaping Kim Jeong-Ho Kim Dae Jin Park Hosung Kim Jin Young Hwang Intae 《Wireless Personal Communications》2018,102(1):383-398
Wireless Personal Communications - Vehicle communication can facilitate efficient coordination among vehicles on the road and enable future vehicular applications such as vehicle safety... 相似文献