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Differentiation of atypical hepatic hemangioma from liver metastases: Diagnostic performance of a novel type of color contrast enhanced ultrasound 被引量:11
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作者 Xiao-Feng Wu Xiu-Mei Bai +5 位作者 Wei Yang Yu Sun Hong Wang Wei Wu, Min-Hua Chen Kun Yan 《World Journal of Gastroenterology》 SCIE CAS 2020年第9期960-972,共13页
BACKGROUND In clinical practice,the diagnosis is sometimes difficult with contrast-enhanced ultrasound(CEUS)when the case has an atypical perfusion pattern.Color parametric imaging(CPI)is an analysis software for CEUS... BACKGROUND In clinical practice,the diagnosis is sometimes difficult with contrast-enhanced ultrasound(CEUS)when the case has an atypical perfusion pattern.Color parametric imaging(CPI)is an analysis software for CEUS with better detection of temporal differences in CEUS imaging using arbitrary colors.It measures the differences in arrival time of the contrast agent in lesions so that the perfusion features of atypical hemangioma and colorectal cancer(CRC)liver metastasis can be distinguished.AIM To evaluate the role of a novel type of CPI of CEUS in the differential diagnosis of atypical hemangioma from liver metastases in patients with a history of CRC.METHODS From January 2016 to July 2018,42 patients including 20 cases of atypical hemangioma and 22 cases of liver metastases from CRC were enrolled.These patients had a mean age of 60.5±9.3 years(range:39-75 years).All patients received ultrasound,CEUS and CPI examinations.Resident and staff radiologists independently and retrospectively reviewed CEUS and CPI images.Two sets of criteria were assigned:(1)Routine CEUS alone;and(2)CEUS and CPI.The diagnostic sensitivity,specificity,accuracy and receiver operating characteristic(ROC)curve of resident and staff radiologists were analyzed.RESULTS The following CPI features were significantly different between liver hemangioma and liver metastases analyzed by staff and resident radiologists:Peripheral nodular enhancement(65%-70.0%vs 4.5%-13.6%,P<0.001,P=0.001),mosaic/chaotic enhancement(5%-10%vs 68.2%-63.6%,P<0.001,P<0.001)and feeding artery(20%vs 59.1%-54.5%,P=0.010,P=0.021).CPI imaging offered significant improvements in detection rates compared with routine CEUS in both resident and staff groups.By resident radiologists,the specificity and accuracy of CEUS+CPI were significantly increased compared with that of CEUS(77.3%vs 45.5%,P=0.030;78.6%vs 50.0%,P=0.006).In addition,the area under the curve(AUC)of CEUS+CPI was significantly higher than that of CEUS(0.803 vs 0.757,P=0.036).By staff radiologists,accuracy was improved in CEUS+CPI(81.0%vs 54.8%,P=0.010),whereas no significant differences in specificity and sensitivity were found(P=0.144,P=0.112).The AUC of CEUS+CPI was significantly higher than that of CEUS(0.890 vs 0.825,P=0.013)by staff radiologists.CONCLUSION Compared with routine CEUS,CPI could provide specific information on the hemodynamic features of liver lesions and help to differentiate atypical hemangioma from liver metastases in patients with CRC,even for senior radiologists. 展开更多
关键词 color parametric imaging contrast enhanced ultrasound Liver hemangioma Liver metastases
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Quantitative Relationship Between Simultaneous Color Contrast and Hue Difference in Complex Displays
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作者 李为 汤遇春 《Journal of Beijing Institute of Technology》 EI CAS 2000年第1期25-30,共6页
To investigate quantitatively one of the parametric effects——simultaneous color contrast on color appearance and color difference evaluation in complex displays, a set of center/surround combinations of color stimu... To investigate quantitatively one of the parametric effects——simultaneous color contrast on color appearance and color difference evaluation in complex displays, a set of center/surround combinations of color stimuli were displayed on a color monitor and the perceived color shifts of test targets induced by its surrounds were measured using binocular matching method while systematically varying hue difference between target and surround. When the hue difference increased, the magnitude of color shift in test target decreased, but the deflection angle of color shift vector from constant hue line increased. Regression analyses of experimental data indicated that the relationship between hue angle difference and the magnitude of perceived color shifts could be described quantitatively by an exponential function, and a linear function could describe quantitative relationship between hue angle difference and deflection angle of color shift vector from constant hue line. 展开更多
关键词 simultaneous color contrast color perception information displays
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Contrast Application of Color Designs in Chicago Botanic Garden
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作者 WU Dongmei 《Journal of Landscape Research》 2016年第2期27-28,34,共3页
This paper elaborated the role of color composition in plant landscape design of Chicago Botanic Garden systematically, used examples to analyze color design of plant landscapes in the garden, and the specifi c applic... This paper elaborated the role of color composition in plant landscape design of Chicago Botanic Garden systematically, used examples to analyze color design of plant landscapes in the garden, and the specifi c application of color contrast in wall plant decoration, courtyard waterscape, indoor greenhouse and tree decoration, to provide detailed references for plant landscape design of China. 展开更多
关键词 color contrast Landscape design Applied research
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Semantic Contrastive Analysis between English and Chinese Color Terms
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作者 朱海群 《教师》 2009年第10期125-127,共3页
关键词 英语 词义 汉语 教学方法
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The contrastive study of cultural connotations of color words in English and Chinese——Take“red”and“红色”for Example 被引量:1
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作者 王锦玲 《海外英语》 2014年第18期253-254,共2页
Color words, as a part of language, has different cultural connotations in different culture, which usually express strong cultural characteristics. This thesis explores the similarities and differences between the co... Color words, as a part of language, has different cultural connotations in different culture, which usually express strong cultural characteristics. This thesis explores the similarities and differences between the color word"red"and"红色". Further comprehension of color words in different cultural background can help us to communicate with others successfully. 展开更多
关键词 contrastIVE study CULTURAL connotations color WORD
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A Contrast of Cultural Connotations between English and Chinese Color Terms
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作者 孙昌娟 《科技信息》 2012年第15期278-279,332,共3页
Color is perception of people to the objective world.In human language,there are great numbers of color terms recording color of the world.These color terms are often used in human language.Gradually,they are endowed ... Color is perception of people to the objective world.In human language,there are great numbers of color terms recording color of the world.These color terms are often used in human language.Gradually,they are endowed with rich emotional elements and cultural connotations.In cross-cultural communication,different nations with different cultural backgrounds or people of the same nations with the same backgrounds but belonging to different social classes have different perceptions of various colors.The different perceptions of colors result in a series of associative meaning of color terms.This thesis intends to discuss color terms from the following five aspects.Firstly,it deals with the relationship between language and culture.Language and culture are connected with each other.So the understanding of a culture requires the understanding of the corresponding language and vice versa.Secondly,it aims at the contrast of cultural connotations of basic color terms in English and Chinese.Thirdly,it is devoted to a discussion of the possible reasons for the diversity of cultural connotations in the two languages.Fourthly,it focuses on the influences on the cross-cultural communication. 展开更多
关键词 职业技术教育 教育理论 人才培养 职业技术学院
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Using of Color Model and Contrast Variation in Wavelet Ideology for Study <i>Megaloblastic Anemia Cells</i>
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作者 Vyacheslav V. Lyashenko Asaad MA. Babker 《Open Journal of Blood Diseases》 2017年第3期86-102,共17页
Processing and analyzing of medical images is one of the priority research areas. At the same time, the processing of images of cells occupies a special place. This is due to the fact that such studies allow for a com... Processing and analyzing of medical images is one of the priority research areas. At the same time, the processing of images of cells occupies a special place. This is due to the fact that such studies allow for a comprehensive diagnosis of the state of human health, identify and prevent the development of diseases in the early stages. We investigate the effectiveness of using wavelet analysis in color models, taking into account the preliminary change in the contrast of the input image. We consider the HSV color model and the image contrast modification procedure, which is based on the histogram change in the specified range with gamma correction. As a criterion for choosing parameters for changing the contrast of the image, we consider the entropy of the image. We also showed the advisability of using the value of the entropy index for the subsequent improvement of image analysis based on the wavelet ideology. We examined the general sequence of action for the analysis of image of megaloblastic anemia cells. This sequence is based on the choice of parameters for changing the contrast of the image and application of wavelet ideology. 展开更多
关键词 WAVELET Analysis Image contrast Enhancement Medicine color Model Megaloblastic ANEMIA CELLS
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Hemodynamic Changes on Color Doppler Flow Imaging and Intravenous Contrast-enhanced Ultrasound for Assessing Transplanted Liver and Early Diagnosis of Complications 被引量:1
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作者 黄道中 陈云超 +1 位作者 李开艳 张青萍 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第3期284-286,共3页
The value of color Doppler flow imaging (CDFI) and intravenous contrast-enhanced ultrasound (CEUS) for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discu... The value of color Doppler flow imaging (CDFI) and intravenous contrast-enhanced ultrasound (CEUS) for assessing the transplanted liver and early diagnosing complications by examining hemodynamic changes was discussed. Seventy-five patients with orthotopic liver transplantation (OLT) underwent CDFI. The following parameters were measured: peak systolic velocity (PS), resistance index (RI) and Doppler perfusion index (DPI) of the hepatic artery (HA), time average velocity (TAV) of portal vein (PV) and velocity of hepatic vein (HV) in different stages postoperation, And 11 patients of them received CEUS. Thirty healthy subjects were enrolled as controls, The results showed that: (1) In 23 patients without obvious complications, TAV of PV within 15 days post-operation was significantly higher than in controls (P〈0.05), PS and DPI of HA within 7 days postoperation were lower, but RI was higher than in controls (P〈0.05); (2) When the hepatic artery thrombosis (HAT) occurred, PS and DPI of HA were obviously decreased, but TAV of PV significantly increased like a high saw-tooth wave; (3) While rejection occurred, both TAV of PV and PS of HA were decreased with the increase in RI of HA, and the triphasic wave of HV disappeared and displayed as saw-tooth wave; (4) The incidence of biliary complications in liver transplantation was increased when DPI was reduced; (5) Seven cases of hepatic carcinoma relapse after OLT demonstrated hyperecho in the arterial phase and hypoecho in the portal and later phase on CEUS; (6) In 2 cases of HA thrombus, there was no visualized enhancement in arterial phase of CEUS, but enhancement during the portal vein and parenchymal phase. It was concluded that the hemodynamic changes of PV, HA and HV in the transplanted liver are valuable for assessing the transplanted liver and early diagnosing complications on CDFI and CEUS. 展开更多
关键词 color Doppler flow imaging liver transplantation HEMODYNAMICS postoperative complications intravenous contrast-enhanced ultrasound
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超声定量参数、sTWEAK联合预测急性心肌梗死患者并发心力衰竭价值
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作者 张曦 朱晓玲 《影像科学与光化学》 2026年第1期66-71,78,共7页
目的:探讨超声定量参数、可溶性肿瘤坏死因子样凋亡弱诱导因子(sTWEAK)联合预测急性心肌梗死(AMI)患者并发心力衰竭(HF)价值,以辅助临床决策,降低HF发生风险。方法:选取2021年5月至2023年5月自贡市第四人民医院收治的116例AMI患者作为... 目的:探讨超声定量参数、可溶性肿瘤坏死因子样凋亡弱诱导因子(sTWEAK)联合预测急性心肌梗死(AMI)患者并发心力衰竭(HF)价值,以辅助临床决策,降低HF发生风险。方法:选取2021年5月至2023年5月自贡市第四人民医院收治的116例AMI患者作为研究组(AMI患者组),另遵循1:1原则纳入同期116例冠脉造影正常者作为对照组(冠脉造影正常组)。比较两组入院即刻彩超参数[左心室射血分数(LVEF)、左室收缩末期内径(LVEDD)、室壁运动积分(WMS)]、实时心肌造影(MCE)参数[心肌血流量(A·β)、时间-强度曲线上升斜率(β)、灌注计分指数(PSI)]、sTWEAK,同时根据AMI发病3周内是否发生HF,分为HF亚组和非HF亚组,统计两亚组一般资料、入院即刻超声定量参数、sTWEAK,采用偏相关性分析超声定量参数、sTWEAK与HF之间关系,采用受试者操作特征曲线及曲线下面积(AUC)分析预测效能。结果:(1)研究组血清sT-WEAK表达及LVEDD、WMS较对照组高,A·β、β、PSI、LVEF较对照组低(P<0.05);(2)两组亚组梗死位置、多支血管闭塞(≥2支)、sTWEAK、MCE参数、彩超参数上存在显著差异(P<0.05);(3)控制梗死位置、多支血管闭塞(≥2支)等混杂因素后,sTWEAK与HF发生呈正相关,A·β、PSI、LVEF与HF发生呈负相关(P<0.05);(4)sTWEAK、A·β、PSI、LVEF四者联合预测HF的AUC最大,值为0.934,敏感度及特异度分别为87.50%、88.16%。结论:超声定量参数、sTWEAK在AMI患者中呈异常表达,四者联合可提高HF的预测效能,为临床决策提供依据,有助于降低HF发生风险。 展开更多
关键词 急性心肌梗死 心力衰竭 彩超 实时心肌造影 可溶性肿瘤坏死因子样凋亡弱诱导因子
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Effective color correction method employing HSV color model 被引量:5
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作者 Jae-hyoung YU Young-tak KIM +2 位作者 Nam-ki LEE Young-sun TCHOI Hern-soo HAHN 《Journal of Measurement Science and Instrumentation》 CAS 2012年第1期39-45,共7页
This paper suggests a new algorithm to solve problems of the current retinex algorithm such as distortion of grey out and color noise due to the individual treatment of RGB channel and log function,and halo effect occ... This paper suggests a new algorithm to solve problems of the current retinex algorithm such as distortion of grey out and color noise due to the individual treatment of RGB channel and log function,and halo effect occurred by use of the Gaussian filter.The current retinex algorithm treats each channel in RGB space that brings a phenomenon to change the rate of RGB.To improve this phenomenon,the color information was fixed in the HSV color space,and retinex treatment was conducted against the V value,a luminance feature.Linear treatment was carried out to remove color noise occurred by the use of log function.S value,a saturation value was compensated in proportion to the change of V value in luminance to obtain a clearer image.The proposed algorithm was evaluated against the landscape images that had strong backlit phenomena,and it is proved to have a better performance than the current retinex algorithm,multiscale retinex with cdor restoration(MSRCR). 展开更多
关键词 RETINEX multiscale retinex with cdor restoration(MSRCR) color HSV contrast enhancement
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Color Composition and Role of Environmental Landscapes in Hengdaohezi Town,Heilongjiang Province of China 被引量:1
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作者 WANG An'an 《Journal of Landscape Research》 2012年第11期40-42,共3页
From the perspective of color expression based on visual perception theories,Hengdaohezi Town was investigated,color composition and role of three typical regions were explored.It was believed that regional landscape ... From the perspective of color expression based on visual perception theories,Hengdaohezi Town was investigated,color composition and role of three typical regions were explored.It was believed that regional landscape color was composed of dominant color, interface color and decorative color,and was perceived by observers for their diversified compositions.By analyzing color effects of the regional environmental landscapes,rational suggestions were proposed to protect the color environment according to actual situation of the town. 展开更多
关键词 Landscape color COMPOSITION contrast HARMONY ROLE
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面向用户体验优化的文化遗产纪录视频色彩校正技术研究
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作者 杜文倩 杨超 徐永涛 《现代电影技术》 2025年第7期63-71,共9页
文化遗产纪录视频的场景拍摄通常具有复杂的非均匀分布光照。这种光照的空间异质性使图像中的色彩区域差异大,色彩校正难度高、还原度低,影响用户体验。为此,本研究提出面向用户体验优化的色彩校正技术:首先依据视频图像原始对比度与二... 文化遗产纪录视频的场景拍摄通常具有复杂的非均匀分布光照。这种光照的空间异质性使图像中的色彩区域差异大,色彩校正难度高、还原度低,影响用户体验。为此,本研究提出面向用户体验优化的色彩校正技术:首先依据视频图像原始对比度与二阶颜色矩阵,计算对比度局部测量值,结合单通道响应边缘函数求取颜色分布特征,增强优化画面;再利用超像素分割法分割图像,结合画面色彩偏差纠正系数归纳超像素,消除色彩偏差;最后还原暗化边缘,确定运动残差,结合采样方差法完成色彩校正。实验表明,本方法在提高对比度、清晰度,优化阴影、纠正色彩偏差等方面效果良好,校正图像与参考图像直方图相似度超0.80,处理视频影像平均速度可提升至4秒/个。该方法对文化遗产纪录视频色彩还原度较高,处理性能出色,能够有效优化用户体验。 展开更多
关键词 用户体验优化 色彩校正 对比度 色彩偏差纠正
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基于视觉传达的光照变化条件偏振图像修复研究
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作者 晏志英 吴婕 《激光杂志》 北大核心 2025年第6期114-118,共5页
针对光照变化可能导致图像信息丢失、细节模糊,进而影响图像的视觉传达效果问题,提出基于视觉传达的光照变化条件偏振图像修复方法。利用了多元化先验信息构建入射光能量补偿目标方程,采取交替迭代法求解,实现偏振图像颜色校正;基于亮... 针对光照变化可能导致图像信息丢失、细节模糊,进而影响图像的视觉传达效果问题,提出基于视觉传达的光照变化条件偏振图像修复方法。利用了多元化先验信息构建入射光能量补偿目标方程,采取交替迭代法求解,实现偏振图像颜色校正;基于亮度可控增强算法的偏振图像对比度增强;基于无监督学习设计由判别器模块与生成器模块,构建偏振图像复原模型,实现偏振图像的修复。实验结果表明,设计方法在水平方向上与垂直方向上平均梯度G较高,分别可达6.8与5.6,两种方向上的平均梯度G整体均比较均衡,说明修复后图像清晰度高,纹理层次均衡。 展开更多
关键词 颜色校正 对比度优化 光照变化条件 偏振图像 图像修复
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超声造影诊断铂耐药复发卵巢癌患者靶向治疗后再复发的价值研究
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作者 刘爽 陈熙欢 《实用医院临床杂志》 2025年第6期128-133,共6页
目的探究彩色多普勒超声(CDUS)、超声造影(CEUS)参数与铂耐药复发卵巢癌患者尼拉帕利联合安罗替尼治疗后再复发的关系。方法收集2021年8月至2024年8月我院收治的120例铂耐药复发卵巢癌患者,所有患者均接受尼拉帕利联合安罗替尼治疗,从... 目的探究彩色多普勒超声(CDUS)、超声造影(CEUS)参数与铂耐药复发卵巢癌患者尼拉帕利联合安罗替尼治疗后再复发的关系。方法收集2021年8月至2024年8月我院收治的120例铂耐药复发卵巢癌患者,所有患者均接受尼拉帕利联合安罗替尼治疗,从治疗后开始记录复发,随访24个月,所有患者在治疗完成后均接受CDUS和CEUS检查,并比较CDUS参数[血管阻力指数(RI)、收缩期峰值流速(PSV)]、CEUS参数[造影剂达到肿瘤时间(AT)、达峰时间(TTP)、峰值强度(PI)]的差异,采用多因素Logistic回归分析复发的独立影响因素,绘制受试者工作特征曲线(ROC)分析诊断复发的效能。结果复发组体能状态评分高于非复发组,差异有统计学意义(P<0.05)。复发组CDUS的RI值显著低于非复发组,PSV值显著高于非复发组;CEUS的AT、TTP显著短于非复发组,PI显著高于非复发组,差异均有统计学意义(P<0.05)。多因素Logistic回归分析显示,CDUS的RI、PSV,CEUS的AT、TTP、PI均为复发的独立影响因素(P<0.05);CDUS的RI、PSV,CEUS的AT、TTP、PI诊断复发的AUC分别为0.862、0.738、0.765、0.776、0.727。结论CDUS和CEUS参数在评估铂耐药复发卵巢癌患者接受尼拉帕利联合安罗替尼治疗后再复发风险中具有一定的参考价值,可作为临床判断再复发可能性的辅助指标。 展开更多
关键词 彩色多普勒超声 超声造影 铂耐药复发卵巢癌 尼拉帕利 安罗替尼 再复发 诊断价值
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经颅彩色多普勒超声联合经颅超声造影与磁共振血管成像在颅内动脉狭窄诊断中的相关性及应用价值 被引量:1
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作者 夏岩 王嵘 +3 位作者 张蕾 林发 刘子琪 王晓岩 《首都医科大学学报》 北大核心 2025年第4期694-701,共8页
目的探究经颅彩色多普勒超声(transcranial color-coded Duplex ultrasound,TCCD)联合超声造影(contrast-enhanced ultrasound,CEUS)检测颅内主要动脉狭窄的灵敏度、特异度及其与磁共振血管成像(magnetic resonance angiography,MRA)检... 目的探究经颅彩色多普勒超声(transcranial color-coded Duplex ultrasound,TCCD)联合超声造影(contrast-enhanced ultrasound,CEUS)检测颅内主要动脉狭窄的灵敏度、特异度及其与磁共振血管成像(magnetic resonance angiography,MRA)检查结果的一致性和应用价值。方法选取2023年4月至2024年8月首都医科大学附属北京天坛医院医院55例疑似颅内动脉狭窄或闭塞患者,分别应用TCCD联合CEUS和MRA,检查颈内动脉终末段、大脑中动脉M1和M2段,大脑前动脉A1和A2段、大脑后动脉P1和P2段以及椎动脉V4段等血管狭窄程度。将颅内动脉狭窄程度分为正常/轻度、中度、重度/闭塞3组,计算两种检查方法的灵敏度、特异度及一致性。采用Wilcoxon符号秩检验比较两种检查费用及诊断时长的差异。结果本研究纳入55例(共110例大脑半球)高危脑血管狭窄患者(中位年龄46岁,男性占69.0%),同步行TCCD联合CEUS与MRA检测。TCCD联合CEUS与MRA在颅内动脉狭窄诊断的灵敏度和特异度较高。TCCD联合CEUS与MRA在诊断颅内动脉狭窄具有一致性,其中M2段(加权Kappa值=0.704)、A2段(加权Kappa值=0.650)诊断一致性较高;M1段(加权Kappa值=0.569)一致性中等。同时,TCCD联合CEUS检查的平均费用为240元,诊断时长21 min,而MRA为722元和287 min(P<0.001,效应量r=0.89~0.91)。结论与MRA相比,TCCD联合CEUS在颅内大脑中动脉M2段和大脑前动脉A2段的血管狭窄筛查中具有较高一致性。TCCD联合CEUS更具成本效益。MRA对颅内深部血管狭窄程度的评估更具有优势。选择二者协同应用可优化颅内血管狭窄诊疗资源配置,建议基层医疗机构以TCCD初筛和经过规范培训技术升级联合CEUS,对复杂病例转诊MRA精细化评估。 展开更多
关键词 经颅彩色多普勒超声 超声造影 磁共振血管成像 颅内动脉 卫生经济学 诊疗模式
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CDFI与超声造影评估头颈部带蒂皮瓣移植术后血流灌注的对比研究
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作者 侯佳欣 李攀 +5 位作者 胡国华 马玮 吴晓安 杨红 唐晋 叶小萍 《临床超声医学杂志》 2025年第9期748-752,共5页
目的对比分析CDFI与超声造影(CEUS)评估头颈部带蒂皮瓣移植术后血流灌注的临床价值。方法前瞻性选取我院行肿瘤根治性切除术的头颈部肿瘤患者13例,术后均行CDFI和CEUS检查(共15次,其中2例患者检查2次),获取血流灌注情况并评估皮瓣结局;... 目的对比分析CDFI与超声造影(CEUS)评估头颈部带蒂皮瓣移植术后血流灌注的临床价值。方法前瞻性选取我院行肿瘤根治性切除术的头颈部肿瘤患者13例,术后均行CDFI和CEUS检查(共15次,其中2例患者检查2次),获取血流灌注情况并评估皮瓣结局;以随访或手术探查皮瓣结局为标准,比较CDFI及CEUS评估皮瓣结局的诊断效能和一致性。以同深度非移植区为对照,应用时间-强度曲线获取达峰时间(TTP)、峰值强度(PI)和曲线下面积(AUC),比较皮瓣坏死组(5例次)、皮瓣存活组(10例次)及非移植区CEUS定量参数的差异。结果CEUS评估皮瓣结局的灵敏度和特异度分别为100%、80.0%,高于CDFI(60.0%、70.0%),差异均有统计学意义(均P<0.05)。一致性分析显示,CDFI评估皮瓣结局与随访或手术探查结果的一致性较低(Kappa=0.286,P=0.264),而CEUS评估皮瓣结局与随访或手术探查结果的一致性较好(Kappa=0.727,P=0.003)。时间-强度曲线分析显示,皮瓣坏死组PI低于非移植区,差异有统计学意义(P=0.026),但与皮瓣存活组比较差异无统计学意义;皮瓣坏死组AUC低于皮瓣存活组及非移植区,差异均有统计学意义(均P<0.05)。结论CEUS在评估头颈部带蒂皮瓣移植术后血流灌注方面显著优于CDFI,具有一定的临床价值。 展开更多
关键词 超声检查 多普勒 彩色 造影剂 头颈部皮瓣 血流灌注
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基于双补偿和对比调节的水下图像增强方法
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作者 赵西超 刘浩 +1 位作者 宫晓蕙 陈根龙 《电光与控制》 北大核心 2025年第10期63-69,共7页
光在水中传播出现衰减和散射,会导致所成的水下图像出现色偏和模糊,这些问题会给后续水下图像特征提取、目标识别等任务带来巨大的挑战。为此,提出了一种基于颜色通道双补偿和对比调节的水下图像增强方法。该方法通过对颜色通道进行双补... 光在水中传播出现衰减和散射,会导致所成的水下图像出现色偏和模糊,这些问题会给后续水下图像特征提取、目标识别等任务带来巨大的挑战。为此,提出了一种基于颜色通道双补偿和对比调节的水下图像增强方法。该方法通过对颜色通道进行双补偿,有效地解决了水下图像色偏的问题。通过参考原始图像对颜色矫正图像在HSV空间进行调节,进一步优化了图像质量。在三个数据集上对比所提方法和其他八种典型的方法,结果显示所提方法的客观评价结果在三个数据集上均位于前列;另外,所提方法的运行时间比其他方法中最快的方法还少36%左右,表明所提方法对不同衰减程度的水下图像都具有良好的颜色矫正能力,并且具有较低的算法复杂度。 展开更多
关键词 水下图像增强 颜色补偿 对比调节 双补偿
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彩色对比敏感度精细化测量及模型建立
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作者 呼香美 廉玉生 +1 位作者 刘江浩 胡永乐 《印刷与数字媒体技术研究》 北大核心 2025年第4期25-32,61,共9页
对比敏感度函数(Contrast Sensitivity Function,CSF)是评价人眼视觉功能的重要参数,用于描述人眼视觉系统的空间特性。目前,对CSF的研究大多仅测量和建立亮度和色度两个模型,而不同色相的CSF差异较大,仅通过亮度和色度CSF模型无法完备... 对比敏感度函数(Contrast Sensitivity Function,CSF)是评价人眼视觉功能的重要参数,用于描述人眼视觉系统的空间特性。目前,对CSF的研究大多仅测量和建立亮度和色度两个模型,而不同色相的CSF差异较大,仅通过亮度和色度CSF模型无法完备表征彩色对比敏感特性。本研究通过开展心理物理实验,精细化测量了6个色相的明度CSF阈值、6个色相的彩度CSF阈值和12个色相的色调CSF阈值;并提出了一种新的指数-高斯CSF函数模型,以精细化表征彩色CSF。经对比分析可知,本研究提出的指数-高斯CSF模型精度明显优于现有模型。 展开更多
关键词 彩色对比敏感度 人眼视觉 CSF模型
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基于多模态超声参数的Logistic回归模型诊断前列腺癌的临床价值
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作者 周隽 郑兵 《临床超声医学杂志》 2025年第3期232-237,共6页
目的 基于多模态超声参数构建诊断前列腺癌(PCa)的Logistic回归模型,探讨其临床应用价值。方法 选取我院收治的疑似PCa患者180例(训练集),依据病理结果分为PCa组93例和非PCa组87例,应用二维超声观察病灶形态、内部回声、包膜、结节、钙... 目的 基于多模态超声参数构建诊断前列腺癌(PCa)的Logistic回归模型,探讨其临床应用价值。方法 选取我院收治的疑似PCa患者180例(训练集),依据病理结果分为PCa组93例和非PCa组87例,应用二维超声观察病灶形态、内部回声、包膜、结节、钙化,应用CDFI对血流分级情况,计算二维超声和CDFI图像阳性率;剪切波弹性成像获取病灶杨氏模量最大值、平均值、最小值(Emax、Emean、Emin);超声造影获取造影剂到达时间、达峰时间、基础强度、峰值强度、强度差、增强强度,比较两组上述检查结果和临床资料的差异。采用多因素Logistic回归分析筛选诊断PCa的独立影响因素,并构建诊断PCa的Logistic回归模型。绘制受试者工作特征(ROC)曲线分析模型的诊断效能;采用HosmerLemeshow拟合优度检验评估模型的拟合度。另选32例疑似PCa患者作为验证集对模型进行外部验证。结果 PCa组血清前列腺特异性抗原、前列腺特异性抗原密度(PSAD)、二维超声和CDFI图像阳性率、Emax、Emean、Emin,以及超声造影峰值强度、强度差、增强强度均高于非PCa组,差异均有统计学意义(均P<0.05);两组其余参数比较差异均无统计学意义。多因素Logistic回归分析显示,血清PSAD、Emax和强度差均为诊断PCa的独立影响因素(均P<0.05),构建的Logistic回归模型为:Logit(P)=1/[1+e^((-10.369+1.134×血清PSAD+×1.359×Emax+1.089×强度差))]。ROC曲线分析显示,模型诊断训练集中PCa的曲线下面积为0.951(95%可信区间:0.929~0.974,P<0.05);Hosmer-Lemeshow拟合优度检验显示模型具有较好的拟合度(χ^(2)=3.696,P=0.883)。外部验证结果显示,模型诊断验证集中PCa的曲线下面积为0.932(95%可信区间:0.876~0.988,P<0.05)。结论 基于多模态超声参数构建的Logistic回归模型在诊断PCa中具有较好的临床应用价值,可为临床准确诊断提供参考依据。 展开更多
关键词 超声检查 多普勒 彩色 造影剂 剪切波弹性成像 前列腺癌
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岭南文化:广彩色彩体系在现代服装设计中的应用
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作者 吴训信 柴柯 金静 《色彩》 2025年第10期54-56,共3页
在全球一体化背景下,我国服装产品存在同质化严重、文化内涵缺失等问题。针对这一问题,本文从岭南文化的广彩色彩体系入手,通过色彩搭配方式的提炼与总结,将传统用色技法应用于现代服装设计实践之中。传统文化及地域性艺术与现代服装设... 在全球一体化背景下,我国服装产品存在同质化严重、文化内涵缺失等问题。针对这一问题,本文从岭南文化的广彩色彩体系入手,通过色彩搭配方式的提炼与总结,将传统用色技法应用于现代服装设计实践之中。传统文化及地域性艺术与现代服装设计互为整合,既是对传统文化的有机继承和观照,亦是对跨文化背景下服装设计创新维度的扩充,期望通过此次研究能够为相关领域提供有价值的借鉴和参考。 展开更多
关键词 广彩 传统用色 服装设计 色彩对比
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