A novel active contour model for serial image segmentation

A novel method for the segmentation of serial images is proposed. In the presented framework, the driving force acts as the attracting term to propel the evolving curve towards the object boundaries, and the adaptive term changes the sign of driving force accordingly. Therefore, the evolving curves can arrive at the desired direction without a requirement for the initial curve to be strictly inside or outside the object. A weighted length term is used to keep the smoothness of curve and penalize the formulation of discontinuities. To prevent the level set function deviating from a signed distance function, a distance rectifying flow is also added to the model; therefore the time-consuming re-initialization procedure is completely avoided. Experiments on both synthetic image and CT serial images demonstrate the feasibility and efficiency of the method.     

High Order Finite Difference Hermite WENO Fixed-Point Fast Sweeping Method for Static Hamilton-Jacobi Equations

In this paper, we combine the nonlinear HWENO reconstruction in [43] andthe fixed-point iteration with Gauss-Seidel fast sweeping strategy, to solve the staticHamilton-Jacobi equations in a novel HWENO framework recently developed in [22].The proposed HWENO frameworks enjoys several advantages. First, compared withthe traditional HWENO framework, the proposed methods do not need to introduceadditional auxiliary equations to update the derivatives of the unknown function $phi$.They are now computed from the current value of $phi$ and the previous spatial derivatives of $phi$. This approach saves the computational storage and CPU time, which greatlyimproves the computational efficiency of the traditional HWENO scheme. In addition,compared with the traditional WENO method, reconstruction stencil of the HWENOmethods becomes more compact, their boundary treatment is simpler, and the numerical errors are smaller on the same mesh. Second, the fixed-point fast sweeping methodis used to update the numerical approximation. It is an explicit method and doesnot involve the inverse operation of nonlinear Hamiltonian, therefore any Hamilton-Jacobi equations with complex Hamiltonian can be solved easily. It also resolves someknown issues, including that the iterative number is very sensitive to the parameter $ε$ used in the nonlinear weights, as observed in previous studies. Finally, to furtherreduce the computational cost, a hybrid strategy is also presented. Extensive numerical experiments are performed on two-dimensional problems, which demonstrate thegood performance of the proposed fixed-point fast sweeping HWENO methods.     

Neuro-fuzzy feature evaluation with theoretical analysis

The article provides a fuzzy set theoretic feature evaluation index and a connectionist model for its evaluation along with their theoretical analysis. A concept of weighted membership function is introduced which makes the modeling of the class structures more appropriate. A neuro-fuzzy algorithm is developed for determining the optimum weighting coefficients representing the feature importance. It is shown theoretically that the evaluation index has a fixed upper bound and a varying lower bound, and it monotonically increases with the lower bound. A relation between the evaluation index, interclass distance and weighting coefficients is established. Effectiveness of the algorithms for evaluating features both individually and in a group (considering their independence and dependency) is demonstrated along with comparisons on speech, Iris, medical and mango-leaf data. The results are also validated using scatter diagram and k-NN classifier.     

多b值扩散加权成像联合DCE-MRI在小肝癌鉴别诊断中的应用

目的 探讨多b值扩散加权成像(DWI)联合动态增强(DCE-MRI)在小肝癌(SHCC)鉴别诊断中的应用.方法 收集2016年3月至2019年3月就诊于我院的临床疑似SHCC患者80例,均行常规MRI、DCE-MRI及多b值DWI检查,分别测量b值为20、60、100、400、600、800s/mm2时病灶的ADC值,...     

336例创伤数据对中国人创伤评分权重系数的评价

目的为了评价国内对ＴＲＩＳＳ评分权重系数的修订，对３３６例创伤患者分别用国外权重和国内权重评定伤情后进行比较。方法３３６例采用ＴＲＩＳＳ法计算生存概率Ｐｓ，所需权重分别采用新近报道的国内权重和国外ＭＴＯＳ权重。Ｐｓ≥０．５预测生存，Ｐｓ＜０．５预测死亡，将预测生死与实际生死结果进行比较。结果中国人权重在敏感性和区别度方面高于国外权重，误判率低于国外权重。结论中国人权重对中国人的创伤程度评估有价值，为进一步精确修订权重，建议建立大型中国人创伤数据库     

酒精性肝炎自噬关键基因的筛选及生物信息学分析

目的 筛选酒精性肝炎（AH）的自噬关键基因,探讨AH潜在的生物标志物和治疗靶点。 方法  采用基因表达综合数据库（GEO）中的2个AH基因芯片和从MSigDB、GeneCards数据库中获得的自噬相关数据集,通过加权基因共表达网络分析（WGCNA）获取关键基因。对筛选的关键基因进行基因本体（GO）、京都基因和基因组百科全书（KEGG）功能富集分析,蛋白质相互作用（PPI）分析,免疫浸润分析,构建信使RNA（mRNA）-微小RNA（miRNA）网络,进行酒精性肝病不同分期的自噬相关关键基因的表达差异分析,并进一步通过实时荧光定量逆转录聚合酶链反应（RT-qPCR）在AH患者和小鼠肝脏组织中验证。 结果  本研究筛选得到了11个与AH自噬相关的基因（EEF1A2、CFTR、SOX4、TREM2、CTHRC1、HSPB8、TUBB3、PRKAA2、RNASE1、MTCL1、HGF）,均为上调基因。在AH患者和小鼠肝脏组织中,SOX4、TREM2、HSPB8、PRKAA2在AH组中的相对表达量均高于对照组。 结论  SOX4、TREM2、HSPB8、PRKAA2可能是AH潜在的生物标志物和治疗靶点。     

Weighted cumulative exposure models helped identify an association between early knee-pain consultations and future knee OA diagnosis

ObjectiveTo establish the association between prior knee-pain consultations and early diagnosis of knee osteoarthritis (OA) by weighted cumulative exposure (WCE) models.Study Design and SettingData were from an electronic health care record (EHR) database (Consultations in Primary Care Archive). WCE functions for modeling the cumulative effect of time-varying knee-pain consultations weighted by recency were derived as a predictive tool in a population-based case-control sample and validated in a prospective cohort sample. Two WCE functions ([i] weighting of the importance of past consultations determined a priori; [ii] flexible spline-based estimation) were comprehensively compared with two simpler models ([iii] time since most recent consultation; total number of past consultations) on model goodness of fit, discrimination, and calibration both in derivation and validation phases.ResultsPeople with the most recent and most frequent knee-pain consultations were more likely to have high WCE scores that were associated with increased risk of knee OA diagnosis both in derivation and validation phases. Better model goodness of fit, discrimination, and calibration were observed for flexible spline-based WCE models.ConclusionWCE functions can be used to model prediagnostic symptoms within routine EHR data and provide novel low-cost predictive tools contributing to early diagnosis.     

脑卒中后失语症患者功能磁共振成像研究

目的 通过多模态磁共振分析脑卒中后失语症患者语言功能区的血流量及代谢改变,阐明失语症的机制,为临床失语症的治疗、预后及康复训练提供理论依据.方法 选取2018年10月至2019年10月就诊于牡丹江医学院附属红旗医院神经内科脑梗死后失语患者,按《西方失语症成套测验》判断所有失语患者类型,共纳入35例脑梗死后失语患者,其中...     

浅谈“甲襞微循环加权积分法”

作者观测了2763例不同病种不同病期患者的甲襞微循环,对于1984年闻世的“甲襞微循环加权积分法”给予高度的评价。同时指出,这种检查方法需要在临床实践中加以充实和提高。作者认为,“管襻脱落”的发生机理和临床意义不同于“管襻出血”,应该把“管襻脱落”作为一项独立的观测指标。汗腺导管的出现率差别很大,应重视其临床意义,增加其权值。甲襞微循环形态,流态及襻周状态部分指标的分值宜作适当的补充和修订。为了把对病人甲襞微循环连续观测的结果更形象更直观地表示出来,作者提出了b=2a-X的校正公式。