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Antidiastole Value of Three-dimensional Ultrasonography and Power Doppler between Uterine Parenchyma Lumps and Endometrial Cancer:A Retrospective Study 被引量:11
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作者 Yan ZHANG Jing CHEN +1 位作者 Zeng ZHEN Xiao-yan XU 《Current Medical Science》 SCIE CAS 2019年第5期816-819,共4页
Sometimes endometrial polyps,submucosal myomas,and endometrial cancer show similar findings under ultrasonography.The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensi... Sometimes endometrial polyps,submucosal myomas,and endometrial cancer show similar findings under ultrasonography.The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensional(3D)power Doppler ultrasonography angiography(PDA)between endometrial cancer and uterine parenchyma lumps.The data of the blood flow indices in 3D-PDA including the vascularization index(VI),flow index(FI),and vascularization flow index(VFI)in 40 patients with endometrial cancer and 41 patients with uterine parenchyma lumps(endometrial polyps and submucosal myomas)were retrospectively analysed and compared utilizing Virtual Organ Computer-aided AnaLysis(VOCAL)software.The results showed that all the blood flow parameters(VI,FI,VFI)were significantly higher in women with endometrial cancer than in those with uterine parenchyma lumps(P<0.001).The area under the curve of ROC of VI,FI,and VFI was 0.98,0.84,and 0.97,respectively.Thus,the best predictor of endometrial carcinoma was VI with a sensitivity of 97.0% and a specificity of 91.0%.The optimal cutoff value of VI was 4.06%.Our data demonstrated that all of the blood flow signal parameters(including VI,FI,and VFI)in 3D power Doppler ultrasonography had significant antidiastole values between endometrial cancer and uterine parenchyma lumps to assist clinicians in properly diagnosing patients. 展开更多
关键词 power doppler three-dimensional ultrasound UTERINE PARENCHYMA lump ENDOMETRIAL CARCINOMA BLOOD flow signal parameter
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Real-time Three-Dimensional Color Doppler Flow Imaging: An Improved Technique for Quantitative Analysis of Aortic Regurgitation 被引量:3
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作者 吕清 刘夏天 +3 位作者 谢明星 王新房 王静 庄磊 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2006年第1期148-152,共5页
The recently introduced real-time three-dimensional color Doppler flow imaging (RT-3D CDFI) technique provides a quick and accurate calculation of regurgitant jet volume (RJV) and fraction. In order to evaluate RT... The recently introduced real-time three-dimensional color Doppler flow imaging (RT-3D CDFI) technique provides a quick and accurate calculation of regurgitant jet volume (RJV) and fraction. In order to evaluate RT-3D CDFI in the noninvasive assessment of aortic RJV and regurgitant jet fraction (RJF) in patients with isolated aortic regurgitation, real-time three-dimensional echocardiographic studies were performed on 23 patients with isolated aortic regurgitation to obtain LV end-diastolic volumes (LVEDV), end-systolic volumes (LVESV) and RJV, and then RJF could be calculated. The regurgitant volume (RV) and regurgitant fraction (RF) calculated by two-dimensional pulsed Doppler (2D-PD) method served as reference values. The results showed that aortic RJV measured by the RT-3D CDFI method showed a good correlation with the 2D-PD measurements (r= 0.93, Y=0.89X+ 3.9, SEE= 8.6 mL, P〈0.001 ); the mean (SD) difference between the two methods was - 1.5 (9.8) mL. % RJF estimated by the RT-3D CDFI method was also correlated well with the values obtained by the 2D-PD method (r=0.88, Y=0.71X+ 14.8, SEE= 6.4 %, P〈0. 001); the mean (SD) difference between the two methods was -1.2 (7.9) %. It was suggested that the newly developed RT-3D CDFI technique was feasible in the majority of patients. In patients with eccentric aortic regurgitation, this new modality provides additional information to that obtained from the two-dimensional examination, which overcomes the inherent limitations of two-dimensional echocardiography by depicting the full extent of the jet trajectory. In addition, the RT-3D CDFI method is quick and accurate in calculating RJV and RJF. 展开更多
关键词 real-time three-dimensional echocardiography color doppler flow imaging aortic regurgitation
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Changes in three-dimensional power Doppler ultrasound features before and after neoadjuvant chemotherapy for cervical cancer and their relationship with malignant molecule expression
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作者 Ju-Hua Pan Ye-Qing Ren Qing-Lian Ma 《Journal of Hainan Medical University》 2019年第11期69-74,共6页
Objective:To study the changes in three-dimensional power Doppler ultrasound features before and after neoadjuvant chemotherapy for cervical cancer and their relationship with malignant molecule expression.Methods: Th... Objective:To study the changes in three-dimensional power Doppler ultrasound features before and after neoadjuvant chemotherapy for cervical cancer and their relationship with malignant molecule expression.Methods: The patients who were diagnosed with cervical cancer and received neoadjuvant chemotherapy in Wuhan Red Cross Hospital between March 2015 and October 2017 were selected as the cervical cancer group, and the patients who received cervical biopsy and were diagnosed with stage I cervical intraepithelial neoplasia by pathological findings during the same period were selected as the control group. Before biopsy, three-dimensional power Doppler ultrasonography was performed to measure VI, FI and VFI;the tissues of cervical cancer group before and after chemotherapy as well as the biopsy tissues of control group were collected to measure the expression of proliferation genes, invasion genes and angiogenesis genes.Results: The VI, FI and VFI levels as well as the Piwil2 gene (Piwil2), CyclinD1, N-Myc downstream regulated gene 3 (NDRG3), CXC chemokine ligand 5 (CXCL5), cathepsin-L (CAT-L), EGF-containing fibulin-like extracellular matrix protein 1 (EFEMP1), angiotensin (Ang)1, Ang2 and angiopoietin-like protein 4 (ANGPTL4) mRNA expression levels in the tissues of cervical cancer group before and after chemotherapy were all significantly higher than those of control group whereas the thrombospondin 2 (THBS2), Smac gene (Smac), large tumor suppressor kinase 1 (LATS1), reversion-inducing-cysteine-rich protein with kazal motifs (RECK) and plas minogen activator inhibitor 1 (PAI-1) mRNA expression levels in the tissues were all significantly lower than those of control group, and the VI, FI and VFI levels as well as the Piwil2, CyclinD1, NDRG3, CXCL5, CAT-L, EFEMP1, Ang1, Ang2 and ANGPTL4 mRNA expression levels in the tissues of cervical cancer group after chemotherapy were all significantly lower than those before chemotherapy whereas the THBS2, Smac, LATS1, RECK and PAI-1 mRNA expression levels were all significantly higher than those before chemotherapy;the VI, FI and VFI levels in cervical cancer tissues were positively correlated with the Piwil2, CyclinD1, NDRG3, CXCL5, CAT-L, EFEMP1, Ang1, Ang2 and ANGPTL4 mRNA expression levels, and negatively correlated with the THBS2, Smac, LATS1, RECK and PAI-1 mRNA expression levels.Conclusion: The changes in the three-dimensional power Doppler ultrasound parameters before and after neoadjuvant chemotherapy for cervical cancer can reflect the changes in proliferation, invasion and angiogenesis gene expression in the lesions. 展开更多
关键词 CERVICAL cancer three-dimensional power doppler ultrasound Proliferation INVASION ANGIOGENESIS
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High-precision three-dimensional atom localization via probe absorption at room temperature
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作者 Mengmeng Luo Wenxiao Liu +1 位作者 Dingyu Cai Shaoyan Gao 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第12期258-264,共7页
A scheme is used to explore the behavior of three-dimensional(3D)atom localization in a Y-type hot atomic system.We can obtain the position information of the atom due to the position-dependent atom–field interaction... A scheme is used to explore the behavior of three-dimensional(3D)atom localization in a Y-type hot atomic system.We can obtain the position information of the atom due to the position-dependent atom–field interaction.We study the influences of the system parameters and the temperature on the atom localization.More interestingly,the atom can be localized in a subspace when the temperature is equal to 323 K.Moreover,a method is proposed to tune multiparameter for localizing the atom in a subspace.The result is helpful to achieve atom nanolithography,photonic crystal and measure the center-of-mass wave function of moving atoms. 展开更多
关键词 three-dimensional atom localization probe absorption doppler effect
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Three-Dimensional Velocity Distribution Measurement Using Ultrasonic Velocity Profiler with Developed Transducer
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作者 Naruki Shoji Hiroshige Kikura +1 位作者 Hideharu Takahashi Wongsakorn Wongsaroj 《Journal of Flow Control, Measurement & Visualization》 2022年第1期32-55,共24页
This study describes an ultrasonic velocity profiler that uses a <span style="white-space:normal;"><span style="font-family:;" "="">new ultrasonic array transducer with u... This study describes an ultrasonic velocity profiler that uses a <span style="white-space:normal;"><span style="font-family:;" "="">new ultrasonic array transducer with unique 5-element configuration</span></span><span style="white-space:normal;"><span style="font-family:;" "="">, with all five elements acting as transmitters and four elements as receivers. The receivers are designed to reduce the amount of uncertainty. As the fluid moves through this setup, four Doppler frequencies are obtained. The multi-dimensional velocity information along the measurement line can be reconstructed. The transducer has a compact geometry suitable for a wide range of applications, including narrow flow areas. The transducer’s basic frequency and sound pressure are selected and evaluated to be compatible with the application. First, to confirm the measurement ability, the measurement of the developed system in two-dimensional flow is validated by comparing it to the theoretical data. The uncertainty of measurement was within 15%. Second, the three-dimensional measurement in turbulent and swirling flow is proved experimentally to check the applicability of the proposed technique.</span></span> 展开更多
关键词 doppler Frequency Liquid Velocity three-dimensional Measurement Transducer Design ULTRASONIC
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Coherent Doppler lidar wind retrieval for a typhoon based on the genetic simulated annealing algorithm
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作者 刘珍 原禄城 +6 位作者 汤杰 张云鹏 刘继桥 竹孝鹏 杨巨鑫 时伟 陈卫标 《Chinese Optics Letters》 SCIE EI CAS CSCD 2024年第4期1-7,共7页
A method of spectrum estimation based on the genetic simulated annealing(GSA)algorithm is proposed,which is applied to retrieve the three-dimensional wind field of typhoon Nangka observed by our research group.Compare... A method of spectrum estimation based on the genetic simulated annealing(GSA)algorithm is proposed,which is applied to retrieve the three-dimensional wind field of typhoon Nangka observed by our research group.Compared to the genetic algorithm(GA),the GSA algorithm not only extends the detection range and guarantees the accuracy of retrieval results but also demonstrates a faster retrieval speed.Experimental results indicate that both the GA and GSA algorithms can enhance the detection range by 35%more than the least squares method.However,the convergence speed of the GSA algorithm is 17 times faster than that of the GA,which is more beneficial for real-time data processing. 展开更多
关键词 coherent doppler lidar three-dimensional wind field retrieval genetic simulated annealing algorithm spectrum estimation TYPHOON
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复式交汇河道水流紊动特性分析 被引量:4
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作者 吴迪 孙可明 郭维东 《沈阳农业大学学报》 CAS CSCD 北大核心 2009年第1期76-79,共4页
利用室内水槽模型,深入模拟了交汇的复式河道水流的流态。采用三维多普勒三向流速仪对复式交汇河流不同垂线的脉动流速进行了观测,并对下游某一断面的时均流速、紊动强度、雷诺应力等沿垂线的分布规律进行了分析。结果表明:在滩槽交界... 利用室内水槽模型,深入模拟了交汇的复式河道水流的流态。采用三维多普勒三向流速仪对复式交汇河流不同垂线的脉动流速进行了观测,并对下游某一断面的时均流速、紊动强度、雷诺应力等沿垂线的分布规律进行了分析。结果表明:在滩槽交界附近存在一个流速间断面,在这个区域水流所受阻力较大,过汇流口后,水槽内水流流态基本符合明渠流动特性。 展开更多
关键词 紊动特性 复式河道 三维多普勒流速仪 流速间断面
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应用LDV对压水反应堆棒束间流场的研究
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作者 宋传琳 孙厚钧 《气动实验与测量控制》 CSCD 1991年第4期28-33,共6页
在50年代,对于反应堆棒束周围的速度分布与湍流强度分布就有人进行过试验研究,但几乎所有的人都是借助于传统的探头,其探头对流场往往会造成剧烈的扰动。本文介绍了用作者研制成的具有高分辨率的偏振差动式激光测速仪(简称 PLDV)测量压... 在50年代,对于反应堆棒束周围的速度分布与湍流强度分布就有人进行过试验研究,但几乎所有的人都是借助于传统的探头,其探头对流场往往会造成剧烈的扰动。本文介绍了用作者研制成的具有高分辨率的偏振差动式激光测速仪(简称 PLDV)测量压水热核反应堆中棒束间的平均速度场分布、湍流强度、自相关函数和功率谱的试验研究,初步结果表明,在平行于棒束轴向棒束间流动参数,其测量结果是准确、合理的,测量系统可靠,其试验方法也是正确的。 展开更多
关键词 激光测速仪 棒束 湍流 强度
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Evaluation of Two Momentum Control Variable Schemes and Their Impact on the Variational Assimilation of Radar Wind Data:Case Study of a Squall Line 被引量:10
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作者 Xin LI Mingjian ZENG +3 位作者 Yuan WANG Wenlan WANG Haiying WU Haixia MEI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第10期1143-1157,共15页
Different choices of control variables in variational assimilation can bring about different influences on the analyzed atmospheric state. Based on the WRF model's three-dimensional variational assimilation system, t... Different choices of control variables in variational assimilation can bring about different influences on the analyzed atmospheric state. Based on the WRF model's three-dimensional variational assimilation system, this study compares the be- havior of two momentum control variable options-streamfunction velocity potential (ψ-χ) and horizontal wind components (U-V)-in radar wind data assimilation for a squall line case that occurred in Jiangsu Province on 24 August 2014. The wind increment from the single observation test shows that the ψ-χ control variable scheme produces negative increments in the neighborhood around the observation point because streamfunction and velocity potential preserve integrals of velocity. On the contrary, the U-V control variable scheme objectively reflects the information of the observation itself. Furthermore, radial velocity data from 17 Doppler radars in eastern China are assimilated. As compared to the impact of conventional observation, the assimilation of radar radial velocity based on the U-V control variable scheme significantly improves the mesoscale dynamic field in the initial condition. The enhanced low-level jet stream, water vapor convergence and low-level wind shear result in better squall line forecasting. However, the ψ-χ control variable scheme generates a discontinuous wind field and unrealistic convergence/divergence in the analyzed field, which lead to a degraded precipitation forecast. 展开更多
关键词 three-dimensional variational assimilation momentum control variable doppler radar data squall line
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The correlation of vascularization index and flow index of thyroid cancer ultrasound with tumor malignancy
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作者 Bing Liao Fan Zeng +1 位作者 Ling Li Qiong Hong 《Journal of Hainan Medical University》 2017年第6期108-111,共4页
Objective:To study the correlation of ultrasound vascularization index and flow index of thyroid cancer with tumor malignancy.Methods: A total of 140 patients with thyroid nodule who accepted surgical resection in our... Objective:To study the correlation of ultrasound vascularization index and flow index of thyroid cancer with tumor malignancy.Methods: A total of 140 patients with thyroid nodule who accepted surgical resection in our hospital between May 2013 and June 2016 were selected as the research subjects, the patients with malignant thyroid nodule were included in the malignant group of the research and patients with benign thyroid nodule were included in the benign group of research. Three-dimensional power Doppler ultrasonography was conducted before operation to determine vascularization index (VI), flow index (FI) and vascularization flow index (VFI);tumor tissues were collected after operation to detect the expression of angiogenesis as well as cell proliferation, apoptosis and invasion-related molecules.Results:VI, FI and VFI levels of tumor tissue of malignant group were significantly higher than those of benign group;VEGF, MK, Ang-2, IGF-Ⅱ, Bcl-2, Livin, Wip1, S100A4, TCF,β-catenin and SATB1 protein expression in tumor tissue of malignant group were significantly higher than those of benign group and positively correlated with VI, FI and VFI levels while CCNG2 and p27 protein expression were significantly lower than those of benign group and negatively correlated with VI, FI and VFI levels.Conclusion:Ultrasound vascularization index and flow index of thyroid cancer increase significantly and are closely related to the angiogenesis as well as cell proliferation, apoptosis and invasion. 展开更多
关键词 THYROID cancer three-dimensional power doppler ULTRASOUND ANGIOGENESIS Proliferation Apoptosis INVASION
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Doppler Radar Data Assimilation with a Local SVD-En3DVar Method 被引量:3
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作者 徐道生 邵爱梅 邱崇践 《Acta meteorologica Sinica》 SCIE 2012年第6期717-734,共18页
An observation localization scheme is introduced into an ensemble-based three-dimensional variational (3DVar) assimilation method based on the singular value decomposition technique (SVD-En3DVar) to im- prove assi... An observation localization scheme is introduced into an ensemble-based three-dimensional variational (3DVar) assimilation method based on the singular value decomposition technique (SVD-En3DVar) to im- prove assimilation skill. A point-by-point analysis technique is adopted in which the weight of each obser- vation decreases with increasing distance between the analysis point and the observation point. A set of numerical experiments, in which simulated Doppler radar data are assimilated into the Weather Research and Forecasting (WRF) model, is designed to test the scheme. The results are compared with those ob- tained using the original global and local patch schemes in SVD-En3DVar, neither of which includes this type of observation localization. The observation localization scheme not only eliminates spurious analysis increments in areas of missing data, but also avoids the discontinuous analysis fields that arise from the local patch scheme. The new scheme provides better analysis fields and a more reasonable short-range rainfall forecast than the original schemes. Additional forecast experiments that assimilate real data from i0 radars indicate that the short-term precipitation forecast skill can be improved by assimilating radar data and the observation localization scheme provides a better forecast than the other two schemes. 展开更多
关键词 doppler radar ENSEMBLE data assimilation 3DVar three-dimensional variational) method SVD (singular value decomposition) localization
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