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51.
Khek Yu Ho 《中国癌症研究》2022,34(5):539
White-light endoscopy with tissue biopsy is the gold standard interface for diagnosing gastric neoplastic lesions. However, misdiagnosis of lesions is a challenge because of operator variability and learning curve issues. These issues have not been resolved despite the introduction of advanced imaging technologies, including narrow band imaging, and confocal laser endomicroscopy. To ensure consistently high diagnostic accuracy among endoscopists, artificial intelligence (AI) has recently been introduced to assist endoscopists in the diagnosis of gastric neoplasia. Current endoscopic AI systems for endoscopic diagnosis are mostly based upon interpretation of endoscopic images. In real-life application, the image-based AI system remains reliant upon skilful operators who will need to capture sufficiently good quality images for the AI system to analyze. Such an ideal situation may not always be possible in routine practice. In contrast, non-image-based AI is less constraint by these requirements. Our group has recently developed an endoscopic Raman fibre-optic probe that can be delivered into the gastrointestinal tract via the working channel of any endoscopy for Raman measurements. We have also successfully incorporated the endoscopic Raman spectroscopic system with an AI system. Proof of effectiveness has been demonstrated in in vivo studies using the Raman endoscopic system in close to 1,000 patients. The system was able to classify normal gastric tissue, gastric intestinal metaplasia, gastric dysplasia and gastric cancer, with diagnostic accuracy of >85%. Because of the excellent correlation between Raman spectra and histopathology, the Raman-AI system can provide optical diagnosis, thus allowing the endoscopists to make clinical decisions on the spot. Furthermore, by allowing non-expert endoscopists to make real-time decisions as well as expert endoscopists, the system will enable consistency of care. 相似文献
52.
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
53.
The coronavirus disease (COVID-19) presented a unique opportunity for the World Health Organization (WHO) to utilise public health intelligence (PHI) for pandemic response. WHO systematically captured mainly unstructured information (e.g. media articles, listservs, community-based reporting) for public health intelligence purposes. WHO used the Epidemic Intelligence from Open Sources (EIOS) system as one of the information sources for PHI. The processes and scope for PHI were adapted as the pandemic evolved and tailored to regional response needs. During the early months of the pandemic, media monitoring complemented official case and death reporting through the International Health Regulations mechanism and triggered alerts. As the pandemic evolved, PHI activities prioritised identifying epidemiological trends to supplement the information available through indicator-based surveillance reported to WHO. The PHI scope evolved over time to include vaccine introduction, emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, unusual clinical manifestations and upsurges in cases, hospitalisation and death incidences at subnational levels. Triaging the unprecedented high volume of information challenged surveillance activities but was managed by collaborative information sharing. The evolution of PHI activities using multiple sources in WHO’s response to the COVID-19 pandemic illustrates the future directions in which PHI methodologies could be developed and used. 相似文献
54.
目的 通过构建基于临床数据中心的可疑呼吸道传染病发现与预测模型, 实现对可疑传染病的发现与预测。 方法 选取某三甲医院的临床数据, 基于历史传染病数据进行病历结构化建模, 构建呼吸道传染病知识图谱, 利用XGboost算法和知识图谱推理技术形成发现与预测合并决策模型, 并使用医院历史数据做交叉验证, 得到准确度较高的模型。 结果 发现与预测模型的平均查准率为92.55%, 查全率为91.49%, 综合F1值为92.01%, 均优于单独的知识图谱模型或XGboost模型, 将模型与医院的电子病历系统和临床辅助决策系统进行集成, 应用于对真实临床病例的预测。 结论 该方法能够很好地针对新发可疑呼吸道传染病进行预测, 辅助医院及时启动传染病应急预案, 减少传染病发生早期时医务人员的感染概率。 相似文献
55.
56.
Yassir Mubarak Hussein Mustafa Mohammad Sharif Zami Omar Saeed Baghabra Al-Amoudi Mohammed A. Al-Osta Yakubu Sani Wudil 《Materials》2022,15(24)
Earth materials have been used in construction as safe, healthy and environmentally sustainable. It is often challenging to develop an optimum soil mix because of the significant variations in soil properties from one soil to another. The current study analyzed the soil properties, including the grain size distribution, Atterberg limits, compaction characteristics, etc., using multilinear regression (MLR) and artificial neural networks (ANN). Data collected from previous studies (i.e., 488 cases) for stabilized (with either cement or lime) and unstabilized soils were considered and analyzed. Missing data were estimated by correlations reported in previous studies. Then, different ANNs were designed (trained and validated) using Levenberg-Marquardt (L-M) algorithms. Using the MLR, several models were developed to estimate the compressive strength of both unstabilized and stabilized soils with a Pearson Coefficient of Correlation (R2) equal to 0.2227 and 0.766, respectively. On the other hand, developed ANNs gave a higher value for R2 than MLR (with the highest value achieved at 0.9883). Thereafter, an experimental program was carried out to validate the results achieved in this study. Finally, a sensitivity analysis was carried out using the resulting networks to assess the effect of different soil properties on the unconfined compressive strength (UCS). Moreover, suitable recommendations for earth materials mixes were presented. 相似文献
57.
Le Peng Gaoxiang Luo Andrew Walker Zachary Zaiman Emma K Jones Hemant Gupta Kristopher Kersten John L Burns Christopher A Harle Tanja Magoc Benjamin Shickel Scott D Steenburg Tyler Loftus Genevieve B Melton Judy Wawira Gichoya Ju Sun Christopher J Tignanelli 《J Am Med Inform Assoc》2023,30(1):54
ObjectiveFederated learning (FL) allows multiple distributed data holders to collaboratively learn a shared model without data sharing. However, individual health system data are heterogeneous. “Personalized” FL variations have been developed to counter data heterogeneity, but few have been evaluated using real-world healthcare data. The purpose of this study is to investigate the performance of a single-site versus a 3-client federated model using a previously described Coronavirus Disease 19 (COVID-19) diagnostic model. Additionally, to investigate the effect of system heterogeneity, we evaluate the performance of 4 FL variations.Materials and methodsWe leverage a FL healthcare collaborative including data from 5 international healthcare systems (US and Europe) encompassing 42 hospitals. We implemented a COVID-19 computer vision diagnosis system using the Federated Averaging (FedAvg) algorithm implemented on Clara Train SDK 4.0. To study the effect of data heterogeneity, training data was pooled from 3 systems locally and federation was simulated. We compared a centralized/pooled model, versus FedAvg, and 3 personalized FL variations (FedProx, FedBN, and FedAMP).ResultsWe observed comparable model performance with respect to internal validation (local model: AUROC 0.94 vs FedAvg: 0.95, P = .5) and improved model generalizability with the FedAvg model (P < .05). When investigating the effects of model heterogeneity, we observed poor performance with FedAvg on internal validation as compared to personalized FL algorithms. FedAvg did have improved generalizability compared to personalized FL algorithms. On average, FedBN had the best rank performance on internal and external validation.ConclusionFedAvg can significantly improve the generalization of the model compared to other personalization FL algorithms; however, at the cost of poor internal validity. Personalized FL may offer an opportunity to develop both internal and externally validated algorithms. 相似文献
58.
在浩瀚的肾移植相关文献中, 本文汲取和盘点2020年肾移植临床国际前沿热点和难点, 移植新技术、新方法、新视野及新进展荟萃, 主要内容包括排斥反应, 免疫抑制优化应用与调控, 移植感染, 移植后恶性肿瘤, 无创检测与生物标志物, 供者器官保存、修复及利用, 肾移植术后肾病复发, 多因素影响移植肾长期存活, 计算机与人工智能等。加强对肾移植领域文献的阅读与思考, 站在更高的起点开拓视野, 结合中国肾移植临床实践, 以推动肾移植获得更好的长期效果。 相似文献
59.
肿瘤新抗原是一类肿瘤特异性抗原,是潜在的肿瘤免疫治疗理想靶标。由于肿瘤新抗原产生及刺激T细胞应答的生理过程复杂,如何高效地发现与鉴定肿瘤新抗原仍是一个巨大的挑战。随着肿瘤免疫基因组学数据的积累和人工智能预测方法的深入研究,研究者能够借助人工智能新算法进行肿瘤新抗原预测方法的研究,为基于肿瘤新抗原的肿瘤免疫治疗奠定坚实的基础。本文围绕肿瘤新抗原胞内处理、抗原提呈和T细胞识别等生理过程系统综述了肿瘤新抗原预测方法的进展。 相似文献
60.