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排序方式: 共有817条查询结果,搜索用时 62 毫秒
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Vasileios Mourmouras Gabriele Cevenini Elena Cosci Maria C. Epistolato Maurizio Biagioli Letizia Barbagli Pietro Luzi Susanna Mannucci and Clelia Miracco 《Journal of cutaneous pathology》2009,36(6):637-646
Background: Nucleolin is a major nucleolar argyrophilic protein involved in carcinogenesis. There are only few studies on its tissue expression in human cancer and none in melanoma. We aimed at exploring this protein and its prognostic impact in cutaneous melanocytic lesions.
Methods: We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.
Results: Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.
Conclusion: An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma. 相似文献
Methods: We studied 193 cases including benign, dysplastic and malignant melanocytic lesions. Nuclear positivity was evaluated by immunohistochemistry and quantified by automated image analysis.
Results: Most dysplastic and malignant lesions showed high percentages of cells with abnormal patterns of nuclear positivity (Abn+N) consisting in multiple, irregular, positive dots (ID+) and a coarse, irregularly positive nucleoplasm (CNpl+) or both (ID+CNpl+). The patterns CNpl+ and/or ID+CNpl+ were never observed in benign lesions, in which ID+ were also virtually absent. Abn+N% was significantly lower in dysplastic nevi than in primary melanomas and metastases and in primary melanomas than in metastases (p < 0.05). Furthermore, Abn+N was the second powerful prognostic discriminator, after melanoma thickness, and a significantly lower survival was observed in vertical growth phase melanoma patients showing Abn+N in more than 50% of melanoma cells.
Conclusion: An altered nuclear nucleolin expression seems to accompany melanoma progression. Further investigation on nucleolin functionality and subcellular trafficking could add information on its altered role in melanoma. 相似文献
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Applying spatial distribution analysis techniques to classification of 3D medical images 总被引:3,自引:0,他引:3
Pokrajac D Megalooikonomou V Lazarevic A Kontos D Obradovic Z 《Artificial intelligence in medicine》2005,33(3):261-280
OBJECTIVE: The objective of this paper is to classify 3D medical images by analyzing spatial distributions to model and characterize the arrangement of the regions of interest (ROIs) in 3D space. METHODS AND MATERIAL: Two methods are proposed for facilitating such classification. The first method uses measures of similarity, such as the Mahalanobis distance and the Kullback-Leibler (KL) divergence, to compute the difference between spatial probability distributions of ROIs in an image of a new subject and each of the considered classes represented by historical data (e.g., normal versus disease class). A new subject is predicted to belong to the class corresponding to the most similar dataset. The second method employs the maximum likelihood (ML) principle to predict the class that most likely produced the dataset of the new subject. RESULTS: The proposed methods have been experimentally evaluated on three datasets: synthetic data (mixtures of Gaussian distributions), realistic lesion-deficit data (generated by a simulator conforming to a clinical study), and functional MRI activation data obtained from a study designed to explore neuroanatomical correlates of semantic processing in Alzheimer's disease (AD). CONCLUSION: Performed experiments demonstrated that the approaches based on the KL divergence and the ML method provide superior accuracy compared to the Mahalanobis distance. The later technique could still be a method of choice when the distributions differ significantly, since it is faster and less complex. The obtained classification accuracy with errors smaller than 1% supports that useful diagnosis assistance could be achieved assuming sufficiently informative historic data and sufficient information on the new subject. 相似文献
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Petter Fagerberg Evangelia Charmandari Christos Diou Rachel Heimeier Youla Karavidopoulou Penio Kassari Evangelia Koukoula Irini Lekka Nicos Maglaveras Christos Maramis Ioannis Pagkalos Vasileios Papapanagiotou Katerina Riviou Ioannis Sarafis Athanasia Tragomalou Ioannis Ioakimidis 《Nutrients》2021,13(3)
Fast self-reported eating rate (SRER) has been associated with increased adiposity in children and adults. No studies have been conducted among high-school students, and SRER has not been validated vs. objective eating rate (OBER) in such populations. The objectives were to investigate (among high-school student populations) the association between OBER and BMI z-scores (BMIz), the validity of SRER vs. OBER, and potential differences in BMIz between SRER categories. Three studies were conducted. Study 1 included 116 Swedish students (mean ± SD age: 16.5 ± 0.8, 59% females) who were eating school lunch. Food intake and meal duration were objectively recorded, and OBER was calculated. Additionally, students provided SRER. Study 2 included students (n = 50, mean ± SD age: 16.7 ± 0.6, 58% females) from Study 1 who ate another objectively recorded school lunch. Study 3 included 1832 high-school students (mean ± SD age: 15.8 ± 0.9, 51% females) from Sweden (n = 748) and Greece (n = 1084) who provided SRER. In Study 1, students with BMIz ≥ 0 had faster OBER vs. students with BMIz < 0 (mean difference: +7.7 g/min or +27%, p = 0.012), while students with fast SRER had higher OBER vs. students with slow SRER (mean difference: +13.7 g/min or +56%, p = 0.001). However, there was “minimal” agreement between SRER and OBER categories (κ = 0.31, p < 0.001). In Study 2, OBER during lunch 1 had a “large” correlation with OBER during lunch 2 (r = 0.75, p < 0.001). In Study 3, fast SRER students had higher BMIz vs. slow SRER students (mean difference: 0.37, p < 0.001). Similar observations were found among both Swedish and Greek students. For the first time in high-school students, we confirm the association between fast eating and increased adiposity. Our validation analysis suggests that SRER could be used as a proxy for OBER in studies with large sample sizes on a group level. With smaller samples, OBER should be used instead. To assess eating rate on an individual level, OBER can be used while SRER should be avoided. 相似文献
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Anastasios Serbis Vasileios Giapros Eleni P Kotanidou Assimina Galli-Tsinopoulou Ekaterini Siomou 《World journal of diabetes》2021,12(4):344-365
During the last two decades, there have been several reports of an increasing incidence of type 2 diabetes mellitus (T2DM) in children and adolescents, especially among those belonging to minority ethnic groups. This trend, which parallels the increases in prevalence and degree of pediatric obesity, has caused great concern, even though T2DM remains a relatively rare disease in children. Youth T2DM differs not only from type 1 diabetes in children, from which it is sometimes difficult to differentiate, but also from T2DM in adults, since it appears to be an aggressive disease with rapidly progressive β-cell decline, high treatment failure rate, and accelerated development of complications. Despite the recent research, many aspects of youth T2DM still remain unknown, regarding both its pathophysiology and risk factor contribution, and its optimal management and prevention. Current management approaches include lifestyle changes, such as improved diet and increased physical activity, together with pharmacological interventions, including metformin, insulin, and the recently approved glucagon-like peptide-1 analog liraglutide. What is more important for everyone to realize though, from patients, families and physicians to schools, health services and policy-makers alike, is that T2DM is a largely preventable disease that will be addressed effectively only if its major contributor (i.e., pediatric obesity) is confronted and prevented at every possible stage of life, from conception until adulthood. Therefore, relevant comprehensive, coordinated, and innovative strategies are urgently needed. 相似文献
7.
Zoi Tsimtsiou Ioanna Tsiligianni Anastasia Papaioannou Dimitrios Gougourelas Konstantinos Kolokas Vasileios Gkizlis Emmanuil Chatzimanolis Philippe-Richard J. Domeyer 《Health & social care in the community》2021,29(3):818-828
Despite the unequivocal value of vaccination in reducing the global burden of infectious diseases, the anti-vaccination movement thrives. The vast majority of the existing validated tools explore attitudes regarding vaccination in children. The aim of our study was to develop and validate a scale assessing attitudes towards adult immunisation. This national cross-sectional study included adult healthcare users who visited 23 Greek Primary Healthcare Units. The development of the scale was the result of literature review, semi-structured interviews and pilot testing of its preliminary versions. The initial version contained 15 items measuring respondents’ attitudes on a 6-point Likert scale. The sample was randomly split into two halves. Exploratory factor analysis, performed in the first sample, was used for the creation of multi-item scales; confirmatory factor analysis was used in the second sample to assess goodness of fit. Moreover, concurrent validity, internal consistency reliability, test–retest reliability and ceiling and floor effects were explored. The total sample consisted of 1,571 individuals. Overall ‘Cronbach's alpha’ (0.821) indicated good internal consistency. The initial exploratory factor analysis resulted in a three-factor model. The subsequent confirmatory factor analysis indicated that an 11-item version of the scale provided the best fit of the model to the data (RMSEA = 0.050, SRMR = 0.053, TLI = 0.937, CFI = 0.955, AIC = 24,999.949). All subscales (‘value of adult vaccination’, ‘safety concerns’ and ‘perceived barriers’) demonstrated strong concurrent associations with participants’ attitudes and behaviour regarding vaccination (p < .001). No ceiling or floor effects were noted for any of the subscales (0.13%, 2.61% and 0.51%; 0.13%, 0.57% and 0.45% respectively). The 11-item ATAVAC scale proved to be a reliable and valid tool, suitable for assessing attitudes towards adult vaccination. 相似文献
8.
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
9.
Charalampos Siristatidis Konstantinos Dafopoulos Nikolas Christoforidis George Anifandis Vasileios Pergialiotis Nikolaos Papantoniou 《Gynecological endocrinology》2017,33(12):968-971
Recombinant DNA technologies have produced Corifollitropin alfa (CFa) used during IVF/ICSI in order to keep the circulating FSH levels above the threshold necessary to support multi-follicular growth for a week. In this prospective case-control study, we compared 70 participants treated with 150?μg CFa combined with 150?IU of follitropin beta (study group) with 70 subfertile participants with matching baseline characteristics, conforming with the same inclusion criteria and treated with an antagonist protocol using follitropin beta (control group). Live birth was the primary outcome, while secondary outcome measures were IVF/ICSI cycles characteristics, including adverse events and complications. Live birth was determined in reduced rates in the study compared to the control group, reaching statistical significance [6/70 versus 20/70, p?=?0.002], as also in the respective number of clinical pregnancies [9/70 versus 23/70, p?=?0.005], although the incidence of miscarriage was similar for both groups [6/70 versus 5/70, p?>?0.99]. Most of the secondary parameters examined were similar between groups. Logistic regression revealed that protocol and AFC had a direct impact on live birth. Ovarian stimulation with CFa does not seem to constitute an equally effective method as compared with follitropin beta to be offered in a general subfertile population seeking IVF/ICSI treatments. 相似文献
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