Quantifying and leveraging predictive uncertainty for medical image assessment

The interpretation of medical images is a challenging task, often complicated by the presence of artifacts, occlusions, limited contrast and more. Most notable is the case of chest radiography, where there is a high inter-rater variability in the detection and classification of abnormalities. This is largely due to inconclusive evidence in the data or subjective definitions of disease appearance. An additional example is the classification of anatomical views based on 2D Ultrasound images. Often, the anatomical context captured in a frame is not sufficient to recognize the underlying anatomy. Current machine learning solutions for these problems are typically limited to providing probabilistic predictions, relying on the capacity of underlying models to adapt to limited information and the high degree of label noise. In practice, however, this leads to overconfident systems with poor generalization on unseen data. To account for this, we propose a system that learns not only the probabilistic estimate for classification, but also an explicit uncertainty measure which captures the confidence of the system in the predicted output. We argue that this approach is essential to account for the inherent ambiguity characteristic of medical images from different radiologic exams including computed radiography, ultrasonography and magnetic resonance imaging. In our experiments we demonstrate that sample rejection based on the predicted uncertainty can significantly improve the ROC-AUC for various tasks, e.g., by 8% to 0.91 with an expected rejection rate of under 25% for the classification of different abnormalities in chest radiographs. In addition, we show that using uncertainty-driven bootstrapping to filter the training data, one can achieve a significant increase in robustness and accuracy. Finally, we present a multi-reader study showing that the predictive uncertainty is indicative of reader errors.     

Four new diarylheptanoids from Rhizoma Zingiberis

Four new diarylheptanoids, (1S, 3R, 5R, 6R)-1, 5-epoxy-3, 6 dihydroxy-1-(4-hydroxy-3, 5-dimethoxyphenyl)-7-(4-hydroxy-3-methoxyphenyl) heptane (1), (1R, 3R, 5S)-1, 5-epoxy-3-acetoxy-1-(4, 5-dihydroxy-3-methoxyphenyl)-7-(3, 4- hydroxyphenyl) heptane (2), (3R, 5S, 6R, 7S)-3, 6-epoxy-7-hydroxyl-1-(4-hydroxyphenyl)-7-(3-methoxy-4-hydroxyphenyl) heptane (3), (E)-3-keto-1-(3-methoxy-4-hydroxyphenyl)-7-(4, 5-dihydroxy-3-methoxyphenyl)-4- heptene (4), were isolated from Rhizoma Zingiberis, and their structures were determined based on HR-ESI-MS and extensive spectroscopic techniques (UV, IR, 1D-NMR and 2D-NMR). Compounds 1–4 exhibited no cytotoxicity against HepG2 cell lines.

     

正念干预改善运动员心理康复效果的系统综述和Meta分析

目的 综合评价正念干预对运动员心理康复的效果。方法 检索2010年1月1日至2019年12月31日Web of Science、EBSCO、PubMed、Medline、OpenDissertations、Psychology and Behavioral Sciences Collection、Academic Search Premier、中国知网(CNKI)、维普和万方数据库有关正念干预促进运动员心理康复的研究,对纳入文献进行质量评价,采用Review Manager 5.3软件进行Meta分析。结果 共纳入18项研究。正念干预对运动员心理康复即刻效果呈中到大效应量(d= 0.69, 95%CI 0.53~0.86, P< 0.001),但存在发表偏倚。正念组干预的追踪效应量不显著(d= -0.08, 95%CI -0.33~0.16, P= 0.50)。正念干预的康复效果受研究质量的影响(I² = 88.1%, P= 0.004)。结论 正念干预对运动员心理康复的效果主要表现为改善心境,促进流畅体验,提高消极体验的接受性,提高对目标的行动力和提高训练的投入程度。正念干预效果受研究质量的影响。     

Evaluation of the short-term results of closed reduction and percutaneous K-wires fixation of displaced intra-articular calcaneal fractures (DIACF)

PurposeOptimum management of displaced intra-articular calcaneal fractures (DIACF) still controversial. Open surgery carries the risk of wound complications, while non-operative management has a high incidence of arthrosis. To avoid these complications, minimally invasive and percutaneous fixation was introduced. The purpose of this study was to prospectively evaluate the short term clinical and radiological outcomes after closed reduction and percutaneous fixation of DIACF using K-wires.Patients and methodsOutcomes of twenty patients were evaluated at the final follow up. A functional assessment using the AOFAS scoring system. Radiological parameters recorded included three angles (Böhler’s, Gissane and posterior facet inclination angles) and three distances (calcaneal length, height and width). Any complications were reported at any follow-up.ResultsThe mean patient’s age was 33 ± 15.2 years, 8 (40%) patients with type II fractures, 10 (50%) patients with type III fractures, and 2 (10%) with type IV fracture according to Sanders classification. After a mean follow-up of 9 months, the mean AOFAS score was 84, excellent in 9 patients (45%), good in 9 (45%), and fair in 2 (10%). At the final follow-up the Böhler’s angle, Gissane angle and PFIA was 25.1° ± (5.2), 119.9° ± (9.4) and 51.7° ± (5.9) respectively and the calcaneal height, length and width was 41.8 mm ± (2.1), 75.1 mm ± (3.01) and 40.9 mm ± (2.6) respectively. We had no cases of deep infection, 20% had significant subtalar arthritis.ConclusionThe closed reduction and percutaneous fixation technique for DIACF management offered acceptable clinical and radiographic outcomes, with fewer complications when compared to other management options.     

大学生网络成瘾量表的初步编制

目的编制可供评估网络成瘾倾向的自评量表。方法采用自编《大学生网络成瘾量表》为研究工具对197名在校大学生为被试进行测试。结果①初步编制的《大学生网络成瘾量表》共46条目,包括2个分量表:网络成瘾倾向和网络成瘾类型分量表,其中网络成瘾倾向分量表分为成瘾症状成分(即成瘾症状、消极影响2个维度)和认知、情感体验成分(即内心体验、自我认知2个维度);网络成瘾类型分为网络关系成瘾、网络娱乐成瘾、信息搜集成瘾和网络性成瘾4个维度;②本量表具有较好的信度:成瘾倾向分量表及各维度的同质性信度为0·80~0·95,网络成瘾类型分量表为0·78,符合测量学标准;网络成瘾倾向分量表及各维度的重测信度除消极影响为0·67外,其他为0·75~0·88,网络成瘾类型分量表为0·74,也都基本达到心理测量学标准;③本量表成瘾倾向分量表的成瘾标志和消极影响维度与陈淑惠《中文网络成瘾量表》各个因子以及总分的相关(0·78~0·83)均显示有统计学意义,说明其具有良好的结构效度。结论该量表评价内容范围较宽、提供信息量较大,题目量适中,并且其信、效度较好,为后续研究打下了良好基础。     

个体成长模型在纵向研究中的应用--以大学新生交往主动性为例

目的介绍个体成长模型方法对大学新生适应能力中交往主动性的3次测查数据采用普通回归模型和个体成长模型进行分析。结果个体成长模型的拟合度比普通回归模型的拟合度要好,个体成长模型可在个体水平上分析个体随时间产生的变化。结论个体成长模型具有许多优点,熟悉这种重要的分析方法对纵向数据研究者是非常有益处的。     

旋转强恒磁场对SD大鼠骨骼生长发育及相关激素的影响

目的探讨旋转强恒磁场（RCSMF）对SD大鼠的骨骼生长发育及相关激素的影响，为RCSMF促进人体增高的临床应用奠定基础。方法取25日龄的SD大鼠置RCSMF下，1．5h／d。每5天取血检测大鼠生长激素（GH）、类胰岛素生长因子（IGF-Ⅰ）、雌激素（E2）等与骨骼发育相关的激素，同时测量每组大鼠的身长、体重和尾长，并用骨形态计量学方法研究RCSMF对大鼠骨组织形态学和动态学参数的影响。结果RCSMF处理后大鼠的身长[实验组（25．28±0．41）cm。对照组（24．05±0．35）cm；P〈0．01]、体重[实验组（445．90±16．88）g，对照组（382．22±12．78）g；P〈0．01]、胫骨长[实验组（3．89±0．13）cm，对照组（3．66±0．10）cm；P〈0．01]和股骨长[实验组（3．65±0．08）cm，对照组（3．51±0．06）cm；P〈0．01]，上述多项参数以及骨骺板等相关形态计量学数据实验组明显高于对照组。回归分析身长与相关激素的关系显示：大鼠身长与GH、IGF—I和E2有显著相关性。结论RCSMF有促进骨骼生长发育的作用，其作用机理是通过刺激与骨骼生长发育相关激素的生成、释放，并影响软骨细胞的增殖功能来完成的。     

Le moment de la crise d'opposition chez l'enfant à risque autistique : un tournant dans la construction psychique

ObjectiveTo contribute to the identification of clinical signs found during the follow-up of children at risk for autism and which reflect a progressive recognition of the other.MethodClinical observation of two autistic children followed from 3 to 5 year-olds in a Part-Time Therapeutic Health Center.ResultsAt the end of the second year of treatment, a discriminate search for the mother's attention and affection is observed, as well as specific reactions to separations and reencounters. Furthermore, when compared with the previous year, the two children present explosive oppositional behaviours which are different from the previous crises of anxious disorganization. This modification of the clinical picture leads us to think that in spite of the absence of verbal language, the rareness of vocalizations and the furtive visual exchanges, a certain recognition of the other in his or her proper characteristics is being built. At the same time it is postulated that this movement is accompanied by a psychic structuring in accordance with the works by A. Bullinger, E. Bick, D. Meltzer and G. Haag.ConclusionThe hypothesis of a pivotal role of the oppositional tantrums will need to be confirmed by other observations made in different clinical contexts.     

PLGA为佐剂的OVA纳米疫苗皮下注射可预防小鼠过敏反应性气道炎症和调节Th1/Th2反应

目的 探讨聚乳酸.羟基乙酸共聚物[poly（D,L-lactic-co-glycolic）acid,PLGA]包裹的卵清蛋白（OVA）纳米癌苗（POM）对哮喘小鼠的免疫治疗效果.方法 包裹不同剂量（低、中、高）的OVA纳米粒子和对照（OVA、空白纳米粒子、PBS）通过皮下注射给予小鼠,再用OVA进行致敏和激发,通过肺组织学、支气管肺泡灌洗液（BALF）细胞计数、测定BALF和脾细胞培养上清液中细胞因子的含量,观察小鼠呼吸道炎症和免疫学改变.结果 肺部组织学和BALF中细胞计数结果显示,与PBS对照组相比,OVA治疗组、中剂量和高剂量OVA纳米组的肺部嗜酸性浸润显著减轻,BALF中总细胞和嗜酸性细胞显著减少.卸胞因子测定结果显示,与PBS对照组相比,中、高剂量OVA纳米组的BALF和脾细胞培养上清液中IFN-γ显著升高,Ⅱ,4水平显著降低.OVA治疗组中IL-4水平显著下降,而IFN-γ水平无显著差异.结论 OVA纳米疫苗可预防哮喘嗜酸性气道炎症,其可能的机制之一是调节了过敏性哮喘的Th1/Th2失平衡反应.