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1.
Stephanie H. Ameis John D. Haltigan Rachael E. Lyon Amanda Sawyer Pat Mirenda Connor M. Kerns Isabel M. Smith Tracy Vaillancourt Joanne Volden Charlotte Waddell Lonnie Zwaigenbaum Teresa Bennett Eric Duku Mayada Elsabbagh Stelios Georgiades Wendy J. Ungar Anat Zaidman-Zait Meng-Chuan Lai Peter Szatmari for the Pathways in ASD Study Team 《Journal of child psychology and psychiatry, and allied disciplines》2022,63(5):553-562
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辽宁省周围血管病及肿瘤介入诊疗技术质控中心 《介入放射学杂志》2022,31(7):642-650
【摘要】 介入联合抗生素已成为肝脓肿的主要治疗手段,但临床工作中仍存在诸多治疗难点且缺乏治疗规范。本共识对肝脓肿介入治疗的适应证及禁忌证、介入治疗操作细节、并发症防治和特殊情况下介入治疗策略进行归纳和说明,并阐述肝脓肿形成原因、危险因素、抗生素选择和预防措施等,旨在为广大临床工作者提供肝脓肿介入治疗的有益指导。 相似文献
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L. Umapathy G.G. Perez-Carrillo M.B. Keerthivasan J.A. Rosado-Toro M.I. Altbach B. Winegar C. Weinkauf A. Bilgin for the Alzheimers Disease Neuroimaging Initiative 《AJNR. American journal of neuroradiology》2021,42(4):639
BACKGROUND AND PURPOSE:Accurate and reliable detection of white matter hyperintensities and their volume quantification can provide valuable clinical information to assess neurologic disease progression. In this work, a stacked generalization ensemble of orthogonal 3D convolutional neural networks, StackGen-Net, is explored for improving automated detection of white matter hyperintensities in 3D T2-FLAIR images.MATERIALS AND METHODS:Individual convolutional neural networks in StackGen-Net were trained on 2.5D patches from orthogonal reformatting of 3D-FLAIR (n = 21) to yield white matter hyperintensity posteriors. A meta convolutional neural network was trained to learn the functional mapping from orthogonal white matter hyperintensity posteriors to the final white matter hyperintensity prediction. The impact of training data and architecture choices on white matter hyperintensity segmentation performance was systematically evaluated on a test cohort (n = 9). The segmentation performance of StackGen-Net was compared with state-of-the-art convolutional neural network techniques on an independent test cohort from the Alzheimer’s Disease Neuroimaging Initiative-3 (n = 20).RESULTS:StackGen-Net outperformed individual convolutional neural networks in the ensemble and their combination using averaging or majority voting. In a comparison with state-of-the-art white matter hyperintensity segmentation techniques, StackGen-Net achieved a significantly higher Dice score (0.76 [SD, 0.08], F1-lesion (0.74 [SD, 0.13]), and area under precision-recall curve (0.84 [SD, 0.09]), and the lowest absolute volume difference (13.3% [SD, 9.1%]). StackGen-Net performance in Dice scores (median = 0.74) did not significantly differ (P = .22) from interobserver (median = 0.73) variability between 2 experienced neuroradiologists. We found no significant difference (P = .15) in white matter hyperintensity lesion volumes from StackGen-Net predictions and ground truth annotations.CONCLUSIONS:A stacked generalization of convolutional neural networks, utilizing multiplanar lesion information using 2.5D spatial context, greatly improved the segmentation performance of StackGen-Net compared with traditional ensemble techniques and some state-of-the-art deep learning models for 3D-FLAIR.White matter hyperintensities (WMHs) correspond to pathologic features of axonal degeneration, demyelination, and gliosis observed within cerebral white matter.1 Clinically, the extent of WMHs in the brain has been associated with cognitive impairment, Alzheimer’s disease and vascular dementia, and increased risk of stroke.2,3 The detection and quantification of WMH volumes to monitor lesion burden evolution and its correlation with clinical outcomes have been of interest in clinical research.4,5 Although the extent of WMHs can be visually scored,6 the categoric nature of such scoring systems makes quantitative evaluation of disease progression difficult. Manually segmenting WMHs is tedious, prone to inter- and intraobserver variability, and is, in most cases, impractical. Thus, there is an increased interest in developing fast, accurate, and reliable computer-aided automated techniques for WMH segmentation.Convolutional neural network (CNN)-based approaches have been successful in several semantic segmentation tasks in medical imaging.7 Recent works have proposed using deep learning–based methods for segmenting WMHs using 2D-FLAIR images.8-11 More recently, a WMH segmentation challenge12 was also organized (http://wmh.isi.uu.nl/) to facilitate comparison of automated segmentation of WMHs of presumed vascular origin in 2D multislice T2-FLAIR images. Architectures that used an ensemble of separately trained CNNs showed promising results in this challenge, with 3 of the top 5 winners using ensemble-based techniques.12Conventional 2D-FLAIR images are typically acquired with thick slices (3–4 mm) and possible slice gaps. Partial volume effects from a thick slice are likely to affect the detection of smaller lesions, both in-plane and out-of-plane. 3D-FLAIR images, with isotropic resolution, have been shown to achieve higher resolution and contrast-to-noise ratio13 and have shown promising results in MS lesion detection using 3D CNNs.14 Additionally, the isotropic resolution enables viewing and evaluation of the images in multiple planes. This multiplanar reformatting of 3D-FLAIR without the use of interpolating kernels is only possible due to the isotropic nature of the acquisition. Network architectures that use information from the 3 orthogonal views have been explored in recent works for CNN-based segmentation of 3D MR imaging data.15 The use of data from multiple planes allows more spatial context during training without the computational burden associated with full 3D training.16 The use of 3 orthogonal views simultaneously mirrors how humans approach this segmentation task.Ensembles of CNNs have been shown to average away the variances in the solution and the choice of model- and configuration-specific behaviors of CNNs.17 Traditionally, the solutions from these separately trained CNNs are combined by averaging or using a majority consensus. In this work, we propose the use of a stacked generalization framework (StackGen-Net) for combining multiplanar lesion information from 3D CNN ensembles to improve the detection of WMH lesions in 3D-FLAIR. A stacked generalization18 framework learns to combine solutions from individual CNNs in the ensemble. We systematically evaluated the performance of this framework and compared it with traditional ensemble techniques, such as averaging or majority voting, and state-of-the-art deep learning techniques. 相似文献
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中国医疗保健国际交流促进会皮肤科分会 《中华皮肤科杂志》2021,54(5):371-375
【摘要】 女阴硬化性苔藓是一种反复发作的慢性炎症性疾病,几乎各年龄阶段均可发生,绝经期、围绝经期和青春期前女性更常见。典型损害为象牙白/瓷白色硬化萎缩斑,晚期可发生外阴、尿道、肛门结构畸变,造成性生活、排尿及排便困难。中国医疗保健国际交流促进会皮肤科分会组织多位专家在借鉴国内外临床研究和诊疗指南的基础上,补充了中国专家的经验和观点,制定女阴硬化性苔藓中国专家共识。 相似文献
6.
Alastair JS Webb Amy Lawson Linxin Li Sara Mazzucco Peter M Rothwell for the Oxford Vascular Study Phenotyped Cohort 《Journal of cerebral blood flow and metabolism》2021,41(6):1463
Cerebral arterial pulsatility is strongly associated with cerebral small vessel disease and lacunar stroke yet its dependence on central versus local haemodynamic processes is unclear. In a population-based study of patients on best medical managment, 4–6 weeks after a TIA or non-disabling stroke, arterial stiffness and aortic systolic, diastolic and pulse pressures were measured (Sphygmocor). Middle cerebral artery peak and trough flow velocities and Gosling’s pulsatility index were measured by transcranial ultrasound. In 981 participants, aortic and cerebral pulsatility rose strongly with age in both sexes, but aortic diastolic pressure fell more with age in men whilst cerebral trough velocity fell more in women. There was no significant association between aortic systolic or diastolic blood pressure with cerebral peak or trough flow velocity but aortic pulse pressure explained 37% of the variance in cerebral arterial pulsatility, before adjustment, whilst 49% of the variance was explained by aortic pulse pressure, arterial stiffness, age, gender and cardiovascular risk factors. Furthermore, arterial stiffness partially mediated the relationship between aortic and cerebral pulsatility. Overall, absolute aortic pressures and cerebral blood flow velocity were poorly correlated but aortic and cerebral pulsatility were strongly related, suggesting a key role for transmission of aortic pulsatility to the brain. 相似文献
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Yasushi Sawayama Hidehiro Itonaga Takuya Fukushima Nobuaki Nakano Hiroshi Fujiwara Atae Utsunomiya Takahiro Fukuda Toshihiro Miyamoto Tetsuya Eto Kaname Miyashita Hirohisa Nakamae Masao Ogata Atsushi Yamanoha Yasuhiko Miyazaki Junya Kanda Yoshiko Atsuta Koji Kato ATL Working Group of the Japan Society for Hematopoietic Cell Transplantation 《American journal of hematology》2019,94(5):E143-E146
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结核病与糖尿病均是临床上的常见病和多发病,两者可合并存在,相互影响。活动性结核病作为感染因素可加重糖尿病病情,而糖尿病患者又是发生结核病的高危人群,结核病与糖尿病双重负担将成为重大的全球公共卫生问题。因此,需重视结核病与糖尿病共病的治疗管理。本共识重点介绍了结核病与糖尿病共病的危害、发病机制、双向筛查、临床特点、诊断、治疗和管理等内容。 相似文献
10.
Arunaloke Chakrabarti Prashant Sood Shivaprakash M. Rudramurthy Sharon Chen Joseph Jillwin Ranganathan Iyer Ajanta Sharma Belgode Narasimha Harish Indranil Roy Anupma J. Kindo Deepinder Chhina Jayanthi Savio Deepak Mendiratta Malini R. Capoor Shukla Das Anita Arora Jagdish Chander Immaculata Xess Appalaraju Boppe Ujjwayini Ray Ratna Rao Vandana Kalwaje Eshwara Sangeeta Joshi Atul Patel Raman Sardana Anjali Shetty Umabala Pamidimukkala for the SIHAM Candidemia Network 《Mycoses》2020,63(11):1149-1163