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排序方式: 共有3473条查询结果,搜索用时 10 毫秒
31.
32.
Kiriakos Stefanidis Dorothea Tsatsou Dimitrios Konstantinidis Lazaros Gymnopoulos Petros Daras Saskia Wilson-Barnes Kathryn Hart Vronique Cornelissen Elise Decorte Elena Lalama Andreas Pfeiffer Maria Hassapidou Ioannis Pagkalos Anagnostis Argiriou Konstantinos Rouskas Stelios Hadjidimitriou Vasileios Charisis Sofia Balula Dias Jos Alves Diniz Gonalo Telo Hugo Silva Alex Bensenousi Kosmas Dimitropoulos 《Nutrients》2022,14(20)
AI-based software applications for personalized nutrition have recently gained increasing attention to help users follow a healthy lifestyle. In this paper, we present a knowledge-based recommendation framework that exploits an explicit dataset of expert-validated meals to offer highly accurate diet plans spanning across ten user groups of both healthy subjects and participants with health conditions. The proposed advisor is built on a novel architecture that includes (a) a qualitative layer for verifying ingredient appropriateness, and (b) a quantitative layer for synthesizing meal plans. The first layer is implemented as an expert system for fuzzy inference relying on an ontology of rules acquired by experts in Nutrition, while the second layer as an optimization method for generating daily meal plans based on target nutrient values and ranges. The system’s effectiveness is evaluated through extensive experiments for establishing meal and meal plan appropriateness, meal variety, as well as system capacity for recommending meal plans. Evaluations involved synthetic data, including the generation of 3000 virtual user profiles and their weekly meal plans. Results reveal a high precision and recall for recommending appropriate ingredients in most user categories, while the meal plan generator achieved a total recommendation accuracy of 92% for all nutrient recommendations. 相似文献
33.
Julian Micallef Alexander N. Baker Sarah-Jane Richards Douglas E. Soutar Panagiotis G. Georgiou Marc Walker Matthew I. Gibson 《RSC advances》2022,12(51):33080
Glycan–lectin interactions play essential roles in biology; as the site of attachment for pathogens, cell–cell communication, and as crucial players in the immune system. Identifying if a new glycan (natural or unnatural) binds a protein partner, or if a new protein (or mutant) binds a glycan remains a non-trivial problem, with few accessible or low-cost tools available. Micro-arrays allow for the interrogation of 100''s of glycans but are not widely available in individual laboratories. Biophysical techniques such as isothermal titration calorimetry, surface plasmon resonance spectrometry, biolayer interferometry and nuclear magnetic resonance spectroscopy all provide detailed understanding of glycan binding but are relatively expensive. Glycosylated plasmonic nanoparticles based on gold cores with polymeric tethers have emerged as biosensors to detect glycan–protein binding, based on colourimetric (red to blue) outputs which can be easily interpreted by a simple UV-visible spectrometer or by eye. Despite the large number of reports there are no standard protocols for each system or recommended start points, to allow a new user to deploy this technology. Here we explore the key parameters of nanoparticle size, polymeric tether length and gold concentration to provide some guidelines for how polymer-tethered glycosylated gold nanoparticles can be used to probe a new glycan/protein interactions, with minimal optimisation barriers. This work aimed to remove the need to explore chemical and nanoparticle space and hence remove a barrier for other users when deploying this system. We show that the concentration of the gold core is crucial to balance strong responses versus false positives and recommend a gold core size and polymer tether length which balances sufficient colloidal stability and output. Whilst subtle differences between glycans/lectins will impact the outcomes, these parameters should enable a lab user to quickly evaluate binding using minimal quantities of the glycan and lectin, to select candidates for further study.Polymer tethered glycosylated gold nanoparticles are optimised to provide a starting point to evaluate glycan–lectin interactions. 相似文献
34.
Panagiotis M. Angelopoulos Nikolaos Rafael Vrithias Zacharias Viskadourakis Petros Tsakiridis Konstantinos C. Vasilopoulos Antonis Peppas Georgios Asimakopoulos Anastasia V. Spyrou Michael A. Karakassides Maria Taxiarchou George Kenanakis 《Materials》2022,15(14)
The use of amorphous microspheres as filler in composites is promising due to their light weight, low cost, incombustibility, and the ability to alter relevant properties of the final composite. Contrary to glass spheres, perlite microspheres are much cheaper and can be tailor-made to facilitate purpose-oriented alteration of the final composite. We report the use of perlite microspheres for the preparation of: (1) composites, through a compression molding (hot pressing) technique; and (2) composite filaments, in a single screw extruder, as well as their use for sample printing through Fused Deposition Modeling (FDM). Proper characterization of the produced composites allows for their evaluation in terms of physical, thermal, and mechanical properties and with regards to the manufacturing technique, the filler fraction, and size. Composite samples of acceptable quality in terms of filler survival and dispersion as well as mechanical properties were produced through compression molding using fine expanded perlite microspheres (<90 μm) up to an infill ratio of 40 vol.%. Fine fillers (<90 μm) performed well in FDM, allowing printing of composite dogbone samples with a higher Young’s modulus and elongation and similar ultimate tensile strength compared to benchmark, up to an infill ratio of 20 vol.%. Composite samples present a slightly lower burning rate compared to those produced solely by ABS. Perlite microspheres present good workability in both applications, possessing satisfactory performance as filler in the composites, and can thus be assumed a promising multifunctional filler for various thermoplastics considering their low price, environmental impact, and fire rating. 相似文献
35.
Serafeim Chlapoutakis Vasiliki Epameinondas Georgakopoulou Nikolaos Trakas Georgios Kouvelos Petros Papalexis Christos Damaskos Pagona Sklapani Anastasios Grivas Panagiotis Gouveris Dimitrios Tryfonopoulos Alexandros Tzovaras Gerasimos Ardavanis-Loukeris Elissavet Grouzi Demetrios A. Spandidos Miltiadis Matsagkas 《Oncology Letters》2022,23(5)
Pulmonary embolism (PE), along with deep vein thrombosis, are collectively known as venous thromboembolism (VTE). Predisposing factors for PE include post-operative conditions, pregnancy, cancer and an advanced age; of note, a number of genetic mutations have been found to be associated with an increased risk of PE. The association between cancer and VTE is well-established, and cancer patients present a higher risk of a thrombotic event compared to the general population. In addition, PE is a significant cause of morbidity and mortality among cancer patients. The aim of the present study was to illustrate the clinical characteristics, laboratory findings, radiology features and outcomes of cancer patients who developed PE, collected from an anticancer hospital. For this purpose, adult cancer patients diagnosed with PE by imaging with computed tomography pulmonary angiography were enrolled. The following data were recorded: Demographics, comorbidities, type of cancer, time interval between cancer diagnosis and PE occurrence, the type of therapy received and the presence of metastases, clinical signs and symptoms, predisposing factors for PE development, laboratory data, radiological findings, electrocardiography findings, and the type of therapy received for PE and outcomes in a follow-up period of 6 months. In total, 60 cancer patients were enrolled. The majority of the cancer patients were males. The most common type of cancer observed was lung cancer. The majority of cases of PE occurred within the first year from the time of cancer diagnosis, while the majority of patients had already developed metastases. In addition, the majority of cancer patients had received chemotherapy over the past month, while they were not receiving anticoagulants and had central obstruction. A large proportion of patients had asymptomatic PE. The in-hospital mortality rate was 13.3% and no relapse or mortality were observed during the follow-up period. The present study demonstrates that elevated levels of lactic acid and an increased platelet count, as well as low serum levels of carcinoembryonic antigen, albumin and D-dimer, may be potential biomarkers for asymptomatic PE among cancer patients. 相似文献
36.
37.
Anastasia Oikonomou Emanuelle Astrinakis Alexandra Giatromanolaki Panagiotis Karros Dimitrios Margaritis Panos Prassopoulos 《General thoracic and cardiovascular surgery》2014,62(3):198-201
A 42-year-old woman undertook a chest radiograph for a routine evaluation prior to surgery for pelvic endometrioma, which revealed a right paratracheal mass slightly displacing the trachea to the left. CT of the thorax disclosed a well demarcated, heterogeneous, lobular, right paratracheal mass, bearing punctate, coarse, and curvilinear calcifications. MRI further revealed two components within the lesion: a larger, cystic, exhibiting thin septations, and a solid component at the lower part exhibiting strong enhancement. No continuity of the mass with the thyroid gland was demonstrated, which had normal size and no focal lesion. Histological examination of the resected mass disclosed lymph node tissue infiltrated by papillary thyroid carcinoma; subsequent total thyroidectomy revealed small foci of papillary carcinoma within both lobes of the thyroid gland. Ablative dose I-131 was administered and the patient was put on daily thyroid supplements. 相似文献
38.
39.
Panagiotis Bouras 《Hellēnikē cheirourgikē. Acta chirurgica Hellenica》2016,88(5):295-296
The complex signaling pathways and interactions inside and among cells which are responsible for the appearance and evolving of malignancy have a distinct and well separated border, the translation process, where the signals of a mutant and dysregulating genome are becoming specific proteins evolving to the malignant phenotype. We selected as translation target the Fragile X–Mental Retardation Protein (FMRP) of the breast cancer cell, a protein of whose role in translation has not clearly elucidated yet. Triple negative breast cancer cell lines (BCCL)-(BT20, MDA-MB-231, Hs578 T) were transfected by plasmid with mutant FMRP at progressively increased CGG triplets (from 45 to 200 repeats at a one by one CGG repeat step up process) and the production of the mutant protein was verified with the SUNSET method and Western blot analysis. Afterwards, the impact in proteinosynthesis inhibition and apoptosis induction of the transfected BCCL in relation to normal epithelial breast cell lines (NEBCL) was evaluated. Preliminary in vitro results showed slower rates of proteinosynthesis and higher apoptotic rate of the 78 CGG & 84 CGG repeat mutant FMRP transfected BCCL in compared to NEBCL, while for all other transfected BCCL no statistically significant differentiation was found. 相似文献
40.
Agreement of infrared temporal artery thermometry with other thermometry methods in adults: systematic review 下载免费PDF全文