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Ultrafast power Doppler imaging for ischemic encephalopathy:A case report
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作者 Li-Jie Huang Jian-Feng Jiao +2 位作者 Qiong He Jian-Wen Luo Yi Guo 《World Journal of Clinical Cases》 SCIE 2023年第31期7640-7646,共7页
BACKGROUND Severely elevated intracranial pressure due to various reasons,such as decreased cerebral perfusion,can lead to devastating neurological outcomes,such as brain herniation.Decompression craniectomy is a life... BACKGROUND Severely elevated intracranial pressure due to various reasons,such as decreased cerebral perfusion,can lead to devastating neurological outcomes,such as brain herniation.Decompression craniectomy is a life-saving procedure that is commonly performed for such a critical situation,but the changes in cerebral microvessels after brain herniation and decompression are unclear.Ultrafast power Doppler imaging(uPDI)is a new microvascular imaging technology that utilizes high frame rate plane/diverging wave transmission and advanced clutter filters.uPDI significantly improves Doppler sensitivity and can detect microvessels,which are usually invisible using traditional ultrasound Doppler imaging.CASE SUMMARY In this report,uPDI was used for the first time to observe the brain blood flow of a hypoperfusion area in a 4-year-old girl who underwent decompression craniectomy due to refractory intracranial hypertension(ICP)after malignant brain tumor surgery.B-mode imaging was used to verify the increased densities of the cerebral cortex and basal ganglia that were observed by computed tomography.CONCLUSION uPDI showed the local blood supplies and anatomical structures of the patient after decompressive craniectomy.uPDI is potentially a more intuitive and noninvasive method for evaluating the effects of severe ICP on cerebral microvessels. 展开更多
关键词 Decompression craniectomy Ultrafast power doppler imaging Cortical layer necrosis Luxury perfusion Case report
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Power Doppler ultrasonographic assessment of the ankle in patients with inflammatory rheumatic diseases 被引量:1
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作者 Takeshi Suzuki 《World Journal of Orthopedics》 2014年第5期574-584,共11页
Ankle involvement is frequent in patients with inflammatory rheumatic diseases, but accurate evaluation by physical examination is often difficult because of the complex anatomical structures of the ankle. Over the la... Ankle involvement is frequent in patients with inflammatory rheumatic diseases, but accurate evaluation by physical examination is often difficult because of the complex anatomical structures of the ankle. Over the last decade, ultrasound(US) has become a practical imaging tool for the assessment of articular and periarticular pathologies, including joint synovitis, tenosynovitis, and enthesitis in rheumatic diseases. Progress in power Doppler(PD) technology has enabled evaluation of the strength of ongoing inflammation. PDUS is very useful for identifying the location and kind of pathologies in rheumatic ankles as well as for distinguishing between inflammatory processes and degenerative changes or between active inflammation and residual damage. The aim of this paper is to illustrate the US assessment of ankle lesions in patients with inflammatory rheumatic diseases, including rheumatoid arthritis, spondyloarthritis, and systemic lupus erythematosus, focusing on the utility of PDUS. 展开更多
关键词 ANKLE power doppler Ultrasound RHEUMATOID ARTHRITIS Psoriatic ARTHRITIS SPONDYLOARTHRITIS TENOSYNOVITIS ENTHESITIS
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Correlation between Perifollicular Vascularity and Outcome in Stimulated Intrauterine Insemination Treatment Cycles: A Study Using Two-Dimensional Transvaginal Power Doppler Ultrasound
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作者 Nadia M. Madkour Wael S. Nossair +3 位作者 Essa M. Arafa Amany M. Abdelghany Ekramy A. Mohamed Walid A. Abdelsalam 《Open Journal of Obstetrics and Gynecology》 2014年第15期973-980,共8页
Objective:?The aim of this study is to assess any potential relationship between perifollicular vascularity and occurrence of pregnancy in cases of stimulated IUI cycles using the subjective grading system by 2D trans... Objective:?The aim of this study is to assess any potential relationship between perifollicular vascularity and occurrence of pregnancy in cases of stimulated IUI cycles using the subjective grading system by 2D transvaginal power Doppler ultrasonography.?Design: A prospective cross sectional cohort study. Method: This is a prospective cross-sectional cohort study of 90 stimulated IUI treatment cycles. Selected women were prescribed clomiphene citrate combined with highly purified urinary follicle stimulating hormone. All patients underwent serial transvaginal ultrasound scans starting from day 6 to 7 of the cycle. Perifollicular Doppler blood flows were assessed in dominant follicles ≥18 mm. The patients then were categorized into 3 groups (high vascularity group {G3 & G4}, low vascularity group {G1 & G2} and mixed grades group). Other parameters measured included number of follicles ≥ 18 mm in both ovaries, endometrial thickness and estradiol (E2) level . Human chorionic gonadotropin (hCG) injection 10,000 IU IM was given to the patient when the dominant follicle reached 18 mm in diameter. At that time, the endometrium was evaluated as regards endometrial thickness. IUI was carried out using prepared/“washed” semen (husband). All patients received luteal support in the form of progesterone from day of IUI for 14 days. Serum Β-hCG was estimated 2 weeks after insemination. Results: In this study, from all 90 cases only 8 cases got pregnant with pregnancy rate of 8.88% (6 cases got pregnant in high grade vascularity group;2 cases in mixed grades group and no cases got pregnant?in low grade group). There was statistically significant difference among the 3 groups as regarding?the pregnancy rate (P value = 0.02). There is statistically significant difference in perifollicular resistance index (RI) and pulsatility index (PI) between pregnant and non pregnant cases (P value = 0.016 and 0.047 respectively). In this study, there is no statistically significant difference between pregnant and non pregnant cases as regarding endometrial thickness and E2 level at the day of hCG administration (P value = 0.39 and 0.76 respectively). Conclusion: Perifollicular blood-flow assessment by 2D transvaginal power Doppler is a good predictive for the outcome of stimulated IUI cycles. 展开更多
关键词 Perifollicular VASCULARITY IUI 2D power doppler Ultrasound
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Preoperative serum vascular endothelial growth factor correlated to three dimensional power Doppler indices in ovarian masses
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作者 Maged R. AbouSeeda Ghada M. Mansour Sahar S. Ez-Elarab 《Open Journal of Obstetrics and Gynecology》 2014年第3期112-119,共8页
Objective: To assess the preoperative serum levels of vascular endothelial growth factor (VEGF) in ovarian masses compared to normal controls and to find a correlation between VEGF and Doppler indices in ovarian masse... Objective: To assess the preoperative serum levels of vascular endothelial growth factor (VEGF) in ovarian masses compared to normal controls and to find a correlation between VEGF and Doppler indices in ovarian masses. Methods: The study was conducted from December 2009 to September 2012 in the oncology and ultrasound units in department of obstetrics and gynecology, Ain Shams University on 150 patients with ovarian masses. During preoperative workup, serum Ca-125 levels and serum VEGF levels were obtained. Ultrasonographic examination included two and three dimensional power Doppler ultrasound (3DPD). Laparotomic approaches were undertaken to obtain the final pathologic results. VEGF was measured in one hundred normal cases as controls. Results: Final ovarian pathology revealed seventy three malignant ovarian masses and seventy seven were benign. Serum Ca-125 levels in malignant cases were higher compared to those in benign cases (p < 0.001). Preoperative serum VEGF revealed higher levels in malignant ovarian masses than benign conditions and normal controls (p < 0.001). Three dimensional power Doppler indices, vascularization index (VI), flow index (FI) and vascularization flow index (VFI), correlated positively with serum VEGF levels. Conclusion: Preoperative serum VEGF revealed higher levels in malignant ovarian masses than benign conditions and normal controls. These levels positively correlated with the Doppler vascular indices of the masses. 展开更多
关键词 OVARIAN Cancer OVARIAN Mass Three DIMENSIONAL power doppler VEGF VI FI VFI
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Comparative Study of Radiological Changes in Hands and Feet in Patients Suffering from Early Rheumatoid Arthritis by Power Doppler Ultrasound and Direct Digital Radiography
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作者 Gargy Mondal Biswadip Ghosh +1 位作者 Manoranjan Ghosh Pampa Halder 《Open Journal of Rheumatology and Autoimmune Diseases》 2014年第1期39-42,共4页
Rheumatoid arthritis is a chronic multisystem disease of unknown cause. The characteristic feature of RA is persistent inflammatory synovitis. The natural history of disease is such that the early months of the diseas... Rheumatoid arthritis is a chronic multisystem disease of unknown cause. The characteristic feature of RA is persistent inflammatory synovitis. The natural history of disease is such that the early months of the disease are critical period during which reversible joint damage occurs. So early diagnosis of RA and appropriate drug application is the only way to save a patient from this crippling disease. In India, the cost of investigations is a significant factor for most of the patients. Ultrasonography or Power Doppler Ultra Sound (PDUS) has the advantage of being economic in spite of its sensitivity in assessing both inflammatory and destructive changes. The aim of the present study was to evaluate the diagnostic efficiency of PDUS in early rheumatoid arthritis. The study was performed with the patients attending Rheumatology Clinic. A total number of 106 patients of clinically suspected rheumatoid arthritis were studied as per selection criteria. Radiological examinations of hands were done by digital radiography and PDUS in a group of 53 patients, assessment of foot changes by PDUS and Digital Radiography were done in another similar group of 53 patients. Final diagnosis by ACR EULAR-2010 criteria is done for all the patients. The comparative study reveals that synovial vascularity as demonstrated by PDUS is much more effective in diagnosing early rheumatoid arthritis, both in hand and in feet than digital radiograph. PDUS of feet may yield earlier and better findings than hands, which is conventionally used in patients suffering from early rheumatoid arthritis. 展开更多
关键词 R.A.—Rheumatoid Arthritis PDUS—power doppler Ultrasound D.R.—Digital Radiography ACR-EULAR—American College of RHEUMATOLOGY (ACR) and the European LEAGUE against RHEUMATISM (EULAR) RF—Rheumatoid Factor CRP—c-Reactive Protein MRI—Magnetic Resonance Imaging
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Use of power Doppler sonography for differential diagnosis of small hepatocellular carcinoma and adenomatous hyperplastic nodule 被引量:1
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作者 徐金锋 吴瑛 +3 位作者 佘志红 王慧芳 冯晓凤 宋红 《Chinese Medical Journal》 SCIE CAS CSCD 2003年第2期212-214,共3页
To evaluate applicability of power Doppler sonography (PDS) in differential diag nosis of small hepatocellular carcinoma (SHCC) and adenomatous hyperplastic nodu le (AHN) Methods Twenty two cases of SHCC and 15 cas... To evaluate applicability of power Doppler sonography (PDS) in differential diag nosis of small hepatocellular carcinoma (SHCC) and adenomatous hyperplastic nodu le (AHN) Methods Twenty two cases of SHCC and 15 cases of AHN were investigated by PDS an d the findings were campared with those of digital subtraction angiography (DSA) Results The rates of arterial and portal flow in an afferent tumor vessel were 86 4% a n d 40 9% in SHCCs, respectively The rate of portal flow in an afferent tumor v essel was 60 0% in AHNs, while no arterial flow was detected ( P <0 01) In addition, PDS revealed a constant flow in an efferent tumor vessel (50 0%) c ontinuing to a portal branch in 10 (45 5%) of the 22 SHCCs cases to a hepatic v ein in 1 (4 5%) of the 22 SHCCs, but to nothing else in the AHNs ( P <0 01) Conclusions Power Doppler sonography is of value in distinguishing SHCC from AHN, and arteri al afferent tumor vessels from constant flow efferent tumor vessels at PDS 展开更多
关键词 power doppler sonography hepatocellular car cinoma adenomatous hyperplastic nodule
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经阴道三维能量多普勒超声联合二维剪切波弹性成像预测备孕女性妊娠结局的临床价值
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作者 冯菲 李瑞霞 +3 位作者 孟文玉 陈高进 张文霞 陈飞 《临床超声医学杂志》 CSCD 2024年第3期223-228,共6页
目的应用经阴道三维能量多普勒超声(3D-PDI)联合二维剪切波弹性成像(2D-SWE)评估备孕女性子宫内膜容受性,探讨其预测妊娠结局的临床应用价值。方法选取在我院接受卵泡检测的87例备孕女性,均于排卵第7~8天(种植窗期)行经阴道3D-PDI检查,... 目的应用经阴道三维能量多普勒超声(3D-PDI)联合二维剪切波弹性成像(2D-SWE)评估备孕女性子宫内膜容受性,探讨其预测妊娠结局的临床应用价值。方法选取在我院接受卵泡检测的87例备孕女性,均于排卵第7~8天(种植窗期)行经阴道3D-PDI检查,于增殖期行2D-SWE检查,然后随访6周,根据妊娠结局将其分为受孕组31例和未受孕组56例。比较两组子宫内膜厚度、容积、回声类型、血流分型、子宫螺旋动脉搏动指数(PI)、阻力指数(RI)、收缩期峰值流速与舒张末期流速比值(S/D)、血管化指数(VI)、血流指数(FI)、血管化血流指数(VFI),以及子宫内膜杨氏模量平均值(以下简称杨氏模量值)的差异。绘制受试者工作特征(ROC)曲线分析经阴道3D-PDI和2D-SWE参数单独及联合应用对备孕女性妊娠结局的预测价值。结果受孕组子宫内膜厚度和FI均高于未受孕组,S/D和子宫内膜杨氏模量值均低于未受孕组,差异均有统计学意义(均P<0.05);两组子宫内膜容积、回声类型、血流分型及PI、RI、VI、VFI比较差异均无统计学意义。ROC曲线分析显示,子宫内膜厚度、FI、S/D和子宫内膜杨氏模量值预测备孕女性妊娠结局的曲线下面积分别为0.789、0.851、0.853和0.840,联合应用的曲线下面积为0.895,高于各参数单独应用,差异均有统计学意义(均P<0.05)。结论经阴道3D-PDI联合2D-SWE可准确评估备孕女性子宫内膜容受性,对预测其妊娠结局有较好的临床应用价值。 展开更多
关键词 超声检查 经阴道 能量多普勒 三维 剪切波弹性成像 二维 备孕女性 子宫内膜容受性 妊娠结局
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三维能量多普勒定量技术对乳腺癌组织学分级的预测价值探讨
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作者 葛丹 姚洁 +2 位作者 姚春 江婷 欧斐 《浙江医学》 CAS 2024年第10期1083-1086,I0004,共5页
目的探讨三维能量多普勒超声(3D-PDUS)中血管定量参数对乳腺癌组织学分级的预测价值。方法回顾性选择2018年1月至2023年6月在杭州市中医院行手术治疗的乳腺癌患者77例(恶性肿块86个),所有肿块均经病理组织学检查证实,根据组织学分级分... 目的探讨三维能量多普勒超声(3D-PDUS)中血管定量参数对乳腺癌组织学分级的预测价值。方法回顾性选择2018年1月至2023年6月在杭州市中医院行手术治疗的乳腺癌患者77例(恶性肿块86个),所有肿块均经病理组织学检查证实,根据组织学分级分为Ⅰ级组、Ⅱ级组、Ⅲ级组。比较3组患者年龄、常规超声检查所见、3D-PDUS指标。常规超声检查所见包括淋巴结转移、肿块内部钙化、肿块Adler血流分级;3D-PDUS指标包括肿块体积、血管参数[血管形成指数(VI)、血流指数(FI)、血管形成-血流指数(VFI)]。应用logistic回归分析乳腺癌组织学分级的危险因素。采用ROC曲线分析VI、FI、VFI对乳腺癌组织学分级的预测准确度。结果Ⅲ级组VI、FI、VFI高于Ⅱ级组,Ⅱ级组高于Ⅰ级组,差异均有统计学意义(均P<0.05)。其中FI为乳腺癌不同组织学分级的独立危险因素(P<0.001)。ROC曲线分析显示VI、FI、VFI对乳腺癌组织学分级的预测准确度均较高(AUC=0.888、0.891、0.894,均P<0.001)。结论3D-PDUS显示的VI、FI、VFI是瘤内血管化重要定量指标,可为乳腺癌患者组织学分级提供可靠的影像学预测信息。 展开更多
关键词 三维能量多普勒超声 乳腺癌 组织学分级 超声 病理
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二维超声联合三维血管成像对慢性子宫内膜炎的诊断价值
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作者 周毛毛 刘玮 +2 位作者 杨洋 陈宥艺 刘莉 《中国妇幼健康研究》 2024年第4期32-37,共6页
目的 探讨经阴道二维超声联合三维能量多普勒血管成像(3D-PDA)检查子宫内膜对慢性子宫内膜炎(CE)的诊断价值。方法 选取2023年1月至2023年8月西安市第四医院收治的210例女性患者作为研究对象,均行经阴道超声及宫腔镜检查,以病理诊断结... 目的 探讨经阴道二维超声联合三维能量多普勒血管成像(3D-PDA)检查子宫内膜对慢性子宫内膜炎(CE)的诊断价值。方法 选取2023年1月至2023年8月西安市第四医院收治的210例女性患者作为研究对象,均行经阴道超声及宫腔镜检查,以病理诊断结果为标准,分为CE组(n=119)和无CE的对照组(n=91),比较两组经阴道二维超声检查的子宫内膜厚度、回声均匀性、子宫内膜Applebaum分型情况,以及3D-PDA检查的子宫内膜血流参数,包括血管化指数(VI)、血流指数(FI)及血管-血流指数(VFI)。采用受试者工作特征(ROC)曲线分析子宫内膜厚度、回声均匀性、子宫内膜Applebaum分型、VI、FI、VFI对CE的诊断价值。结果 CE组子宫内膜厚度、Ⅱ型及Ⅲ型血流占比、VI、FI、VFI均小于对照组,内膜回声不均匀占比、Ⅰ型血流占比均多于对照组(t/χ^(2)值介于-2.831~89.249之间,P<0.05)。ROC曲线分析显示,子宫内膜厚度、内膜回声均匀性、VI、FI、VFI五项联合检测的诊断价值最高,AUC值为0.942,灵敏度87.90%,特异度为79.50%。结论 经阴道二维超声联合三维能量多普勒血管成像检查子宫内膜对CE的诊断价值较高,可作为一种无创性的临床诊断方法推广使用。 展开更多
关键词 慢性子宫内膜炎 三维能量多普勒血管成像 子宫内膜Applebaum分型
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早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限的相关性
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作者 汤倩 姜海娜 +1 位作者 韩宏霞 邓金凤 《中国实验诊断学》 2024年第2期173-178,共6页
目的 分析早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限(FGR)的相关性。方法 选取76例于天津中医药大学附属北辰中医医院2021年4月—2022年9月进行早孕期NT检查的孕妇为研究对象,根据胎儿是否存在生长受限... 目的 分析早孕期三维能量多普勒联合频谱多普勒定量评估胎盘血流灌注预测胎儿生长受限(FGR)的相关性。方法 选取76例于天津中医药大学附属北辰中医医院2021年4月—2022年9月进行早孕期NT检查的孕妇为研究对象,根据胎儿是否存在生长受限分为对照组69例,FGR组7例。以此对比产妇基本资料,两组超声参数:胎盘血管化指数(VI)、胎盘血流指数(FI)、血管化-血流指数(VFI)、子宫动脉阻力指数(UtA-RI)、子宫动脉搏动指数(UtA-PI)、胎儿静脉导管搏动指数(DV-PI),分析发生FGR独立危险因素,超声参数与FGR的相关性,ROC曲线分析不同指标预测FGR的效能。结果 FGR与年龄、BMI指数、孕期贫血、产次无关,无统计学差异(P>0.05);主要与胎膜早破、羊水过少、脐带异常、胎粪污染、胎盘异常有关,具有统计学差异(P<0.05)。与对照组相比,FGR组VI、VFI、水平较低,UtA-RI、UtA-PI、DV-PI水平有所提升(P<0.05)。以FGR为因变量(0=否,1=是),建立Logistic回归模型,结果显示,VI、VFI、UtA-RI、UtA-PI、DV-PI是导致FGR的独立危险因素(P<0.05)。VI、VFI参数与FGR呈负相关;UtA-RI、UtA-PI、DV-PI参数与FGR呈正相关(P<0.05)。ROC曲线显示,VI、VFI、UtA-RI、UtA-PI、DV-PI单一及联合预测均有较高效能,而联合检查预测价值最高(P<0.05)。结论 早孕期采用三维能量多普勒联合频谱多普勒预测FGR的效能较高,有助于早期诊断并及时采取干预措施。 展开更多
关键词 胎儿生长受限 三维能量多普勒 频谱多普勒 胎盘血流灌注 相关性
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融合卫星姿态的星地信道建模及硬件模拟
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作者 周强军 吕崇玉 +3 位作者 陈小敏 华博宇 台鑫 朱秋明 《信号处理》 CSCD 北大核心 2024年第6期1019-1029,共11页
针对传统星地信道模型及其硬件模拟方法没有考虑卫星姿态对信道特性影响的问题,本文基于几何地理随机模型(Geometry-based Stochastic Model,GBSM)框架,提出了一种融合卫星姿态的星地信道模型。该模型通过构建四个独立的坐标系并引入姿... 针对传统星地信道模型及其硬件模拟方法没有考虑卫星姿态对信道特性影响的问题,本文基于几何地理随机模型(Geometry-based Stochastic Model,GBSM)框架,提出了一种融合卫星姿态的星地信道模型。该模型通过构建四个独立的坐标系并引入姿态修正矩阵,来描述卫星姿态变化对星地信道特性造成的影响。在此基础上,本文基于现场可编程门阵列(Field Programmable Gate Array,FPGA),设计并研制了一种星地信道硬件模拟器。硬件模拟器采用差分迭代的算法来生成信道衰落因子,可以极大提高硬件模拟的实时性,确保生成的衰落数据与实际场景相匹配。同时,还采用了并行处理架构,可以支持最大640 MHz带宽的星地信道模拟。为了将衰落数据与并行架构相匹配,引入了并行内插算法,可以将串行的衰落数据内插成同速率的多路并行衰落数据。此外,为了能够精准控制硬件装置输出信号的功率,设计了基于预训练的功率校正方法。通过内部校正源信号预先训练出整个模拟过程给信号带来的增益再进行功率补偿,从而保证输出信号的功率可以被精准控制。最后,在典型场景下开展仿真模拟,导出硬件模拟器的输出结果并分析其统计特性,结果表明实测输出的概率密度函数(Probability Density Function,PDF)和多普勒功率谱密度(Doppler Power Spectral Density,DPSD)与理论值吻合,证明本文设计的硬件模拟器可以准确地复现实际场景下卫星姿态发生变化的星地信道。本文提出的融合卫星姿态的星地信道模型以及研制的硬件模拟器很好地解决了传统模型以及硬件模拟方法的局限性,在卫星通信系统的优化、评估和验证环节具有极大的潜在价值。 展开更多
关键词 星地信道模型 信道模拟 姿态修正矩阵 多普勒功率谱
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超微血流成像及能量多普勒超声技术在监测类风湿关节炎活跃性的应用价值
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作者 彭锦锦 吕海霞 《中国CT和MRI杂志》 2024年第4期154-156,共3页
目的探讨超微血流成像(SMI)及能量多普勒超声(PDUS)技术在监测类风湿关节炎(RA)滑膜炎活跃性的应用价值。方法本研究入选60例RA患者,超声检测其双侧腕关节、掌指关节、近端指间关节,对受累关节的增厚滑膜,分别启用SMI及PDUS两种血流模式... 目的探讨超微血流成像(SMI)及能量多普勒超声(PDUS)技术在监测类风湿关节炎(RA)滑膜炎活跃性的应用价值。方法本研究入选60例RA患者,超声检测其双侧腕关节、掌指关节、近端指间关节,对受累关节的增厚滑膜,分别启用SMI及PDUS两种血流模式,分别记录两种技术的滑膜血流显示率和血流分级,并探讨SMI及PDUS血流分级指数与临床上常用于评估RA活跃性的实验室指标ESR、CRP及DSA28评分之间是否具有正相关性。结果(1)在60例RA患者中,共有450个关节滑膜增厚,PDUS血流模式与SMI血流模式对受累关节增厚滑膜的血流显示率分别为71.8%、81.1%,PDUS对于滑膜内低速血流的敏感性明显低于SMI,差异具有统计学意义(P=0.001)。(2)在RA临床缓解期,PDUS对亚临床滑膜炎显示率为42.9%,明显低于SMI的66.7%,差异具有统计学意义(P=0.028)。(3)PDUS与SMI对滑膜血流分级结果的一致性较好(kappa=0.721,P<0.05),但SMI较PDUS能够更敏感的显示滑膜微血管内的低速血流,提高滑膜血流分级。(4)SMI及PDUS的滑膜血流分级指数与临床上常用于评估RA活跃性的实验室指标ESR、CRP、DAS28呈正相关(P<0.05)。结论SMI技术是一种先进的超声成像技术,它可以较PDUS可以更敏感的显示微小血管内的低速血流信号,帮助临床医生判断滑膜炎的活跃性,尤其在评估RA临床缓解期的患者是否存在亚临床滑膜炎,达到真正缓解中有着一定的优势。 展开更多
关键词 类风湿关节炎 超微血流成像 能量多普勒超声 滑膜炎 活动性
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降水微物理过程的C波段垂直指向雷达反演研究
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作者 黄梓恒 阮征 +2 位作者 何关兴 徐建春 苏德斌 《成都信息工程大学学报》 2024年第2期155-162,共8页
降水微物理过程是对空中雨滴的蒸发、碰并和凝结等演化过程的最直接描述。对降水过程中微物理特征的分析,有利于提高对云体的认识,为降水估计与数值模式参数化提供技术支撑。研究依托中国气象科学研究院灾害天气国家重点实验室在广东龙... 降水微物理过程是对空中雨滴的蒸发、碰并和凝结等演化过程的最直接描述。对降水过程中微物理特征的分析,有利于提高对云体的认识,为降水估计与数值模式参数化提供技术支撑。研究依托中国气象科学研究院灾害天气国家重点实验室在广东龙门建立的超级观测站,基于C波段调频连续波雷达高时空分辨率的多普勒功率谱数据。分析了2020年6月6-9日(前汛期),受西南季风影响,形成的一次持续时间长、累积雨量大、降水分布不均的降水过程中的几种典型对流单体的空中微物理特征。 展开更多
关键词 降水微物理 多普勒功率谱 西南季风 C波段调频连续波雷达
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三维能量多普勒超声在早期不明位置妊娠诊断中的应用价值
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作者 胡凤仪 朱雅芸 +3 位作者 吴杏仪 李惠甄 区薛宜 黄伟俊 《医药前沿》 2024年第1期16-19,共4页
目的:分析三维能量多普勒超声在诊断早期不明位置妊娠(PUL)中的应用价值。方法:选取2022年1—12月广东医科大学顺德妇女儿童医院收治的60例PUL患者,随访至孕12周,根据手术结果或妊娠结局分组,将宫内早孕26例作为宫内组,将异位妊娠22例... 目的:分析三维能量多普勒超声在诊断早期不明位置妊娠(PUL)中的应用价值。方法:选取2022年1—12月广东医科大学顺德妇女儿童医院收治的60例PUL患者,随访至孕12周,根据手术结果或妊娠结局分组,将宫内早孕26例作为宫内组,将异位妊娠22例作为宫外组,将绒毛膜促性腺激素(HCG)下降至阴性且无法确定妊娠位置者12例作为流产组。所有患者均行超声检查,对比三组声像图回声类型、血流分级、黄体血流参数及三维能量多普勒超声血管参数,绘制受试者工作特征曲线(ROC)曲线,分析三维能量多普勒超声对PUL的诊断价值。结果:宫内组黄体厚壁双环型占比较宫外组高(42.31%vs9.09%,P<0.05);宫内组黄体血流分级Ⅲ级率较流产组更高(57.69%vs16.67%,P<0.05);宫外组及流产组RI水平较宫内组更高(P<0.05);流产组RI水平较宫外组更高(P<0.05);宫外组VI、VFI水平较宫内组更低(P<0.05);流产组FI、VFI水平较宫内组更低(P<0.05);RI预测非宫内妊娠结局的AUC为0.841(P<0.05);VI预测的AUC为0.682(P<0.05);FI预测的AUC为0.665(P<0.05);VFI预测的AUC为0.674(P<0.05),RI联合VI预测非宫内妊娠结局的AUC为0.917(P<0.05);RI联合FI预测的AUC为0.870(P>0.05);RI联合VFI预测的AUC为0.912(P>0.05);三组黄体低回声型、混合回声型、薄壁囊肿型比较,差异无统计学意义(P>0.05);三组血流分级Ⅰ级、Ⅱ级比较,差异无统计学意义(P>0.05)。结论:单一三维能量多普勒超声血管参数对PUL中非宫内妊娠结局的诊断价值不高,VI联合RI预测非宫内妊娠结局的诊断效能较高。 展开更多
关键词 早期不明位置妊娠 三维能量多普勒超声 诊断价值 血管形成指数 血流指数
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OFDM通信系统中的一种最大Doppler频移估计算法 被引量:1
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作者 蔡玮 朱光喜 +1 位作者 张青春 李黎 《通信学报》 EI CSCD 北大核心 2005年第11期112-116,124,共6页
在分析了已有各种Doppler估计算法的基础上,根据功率谱估计经典算法——窗函数法的原理,直接利用接收到的频域中连续导频信号,进行最大Doppler频移估计。该算法同时适合于单载波和多载波系统。仿真结果均表明:在单径和多径条件下,该算... 在分析了已有各种Doppler估计算法的基础上,根据功率谱估计经典算法——窗函数法的原理,直接利用接收到的频域中连续导频信号,进行最大Doppler频移估计。该算法同时适合于单载波和多载波系统。仿真结果均表明:在单径和多径条件下,该算法均可对正交频分复用(OFDM)传输系统中的最大Doppler频移获得较精确的估计结果。该算法十分适合于OFDM移动通信系统。 展开更多
关键词 最大doppler频移 正交频分复用 功率谱 窗函数
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三维能量多普勒超声在观察孕早期胎盘血流预测胎儿生长受限中的应用 被引量:3
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作者 王卫平 林雁 赵蒙 《广东医学》 CAS 2023年第2期204-207,共4页
目的探讨三维能量多普勒超声对胎儿生长受限的预测价值研究。方法选取2021年1—12月在医院建卡的正常孕妇400例作为研究对象,全部孕妇于孕早期11~13^(+6)周应用三维能量多普勒超声检查胎盘,获得血管化-血流指数(VFI)、血管化指数(VI)、... 目的探讨三维能量多普勒超声对胎儿生长受限的预测价值研究。方法选取2021年1—12月在医院建卡的正常孕妇400例作为研究对象,全部孕妇于孕早期11~13^(+6)周应用三维能量多普勒超声检查胎盘,获得血管化-血流指数(VFI)、血管化指数(VI)、血流指数(FI)、胎盘体积(PV)、胎盘商(PQ)的水平。绘制受试者工作特征(ROC)曲线分析VFI、VI、FI、PV、PQ对胎儿生长受限的诊断效能。结果正常孕妇400例出现胎儿生长受限35例,发生率为8.75%;将400例孕妇分为研究组35例(胎儿生长受限)和对照组365例(未发生胎儿生长受限)。两组的年龄、孕周、孕次、体质指数、初产妇的资料对比,差异无统计学意义(P>0.05)。研究组的PV、PQ均显著低于对照组,差异有统计学意义(P<0.05)。研究组的VFI、VI、FI均低于对照组,差异有统计学意义(P<0.05)。经ROC曲线分析,PV、VFI、VI的曲线下面积均高于0.7,且高于PQ、FI。PV、PQ、VFI、VI、FI的最大截断值分别为45.83、0.83、7.32、22.70、28.41,特异度为77.89%、67.74%、58.32%、57.99%、74.80%,敏感度为53.72%、73.10%、96.88%、97.60%、58.42%。结论三维能量多普勒超声对胎儿生长受限具有重要的预测价值,能为改变的诊断提供可量化指标。 展开更多
关键词 三维能量多普勒超声 孕早期 胎儿生长受限 胎盘血管参数 预测价值 可量化指标
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Doppler Ultrasound in Post-Molar Gestational Trophoblastic Neoplasia
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作者 Amr H. El-Shalakany Ghada M. Mansour +3 位作者 Nashwa E. Hassan Ibrahim M. Zewel Gamal H. Sari Sahar S. Ez-Elarab 《Open Journal of Obstetrics and Gynecology》 2020年第4期583-598,共16页
Objectives: To evaluate the role of Doppler ultrasound in prediction and follow up during management of gestational trophoblastic neoplasia (GTN). Methods: The study was performed at Oncology Unit, Maternity Hospital,... Objectives: To evaluate the role of Doppler ultrasound in prediction and follow up during management of gestational trophoblastic neoplasia (GTN). Methods: The study was performed at Oncology Unit, Maternity Hospital, Ain Shams University in the period from November 2015 to December 2018. Forty cases of complete mole, after evacuation and follow up of serum human chorionic gonodotrophin (β-hCG) titre until it reached zero level (group I) and forty post molar GTN cases (group II) were included in the study. Doppler ultrasound of the subendometrial and intramural blood flow was done for all cases of group I and II. Doppler included two dimensional and three dimensional power Doppler indices. Group II received Methotrexate (MTX) and folinic acid in a dose of 8-day MTX-FA regimen. Doppler follow up for six months of group II concurrently with the chemotherapy regimen was done. Results: A statistically significant difference was found between group I and II regarding initial readings of all Doppler parameters. Follow up for 6 months of GTN cases revealed progressive statistically significant decrease of intramural and subendometrial three dimensional power Doppler (3DPD) indices, while there was a significant increase in two dimensional (2D) Doppler parameters. Four cases were resistant to Methotrexate chemotherapy. Cut off values were determined for prediction of GTN. Multivariate analysis revealed that the most predictive parameter was the subendometrial pulsatility index (PI), odds ratio = 10.63 (95% CI: 1.30 - 86.89). The cut-off point for sub-endometrial PI was: 2.05 (AUC, 90%;sensitivity, 88%;specificity, 76%, PPV 78%, and NPV 86%) with a diagnostic accuracy of 87%. To and Fro sign may be considered a pathognomonic intramural ultrasound sign for prediction of GTN chemo-resistance or choriocarcinoma. Conclusion: Cut off values for Doppler parameters can be used for early predication of GTN. Doppler ultrasound indices can be used during follow up of GTN cases concurrently with serum β-hCG to monitor the response to treatment. 展开更多
关键词 GESTATIONAL Trophoblastic NEOPLASIA METHOTREXATE Resistance power doppler ULTRASOUND TRANSVAGINAL ULTRASOUND
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三维能量多普勒超声技术产前定量评估对胎儿宫内生长受限的诊断价值研究 被引量:1
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作者 王卫平 《黑龙江医学》 2023年第11期1350-1352,共3页
目的:探讨三维能量多普勒超声技术产前定量评估对胎儿宫内生长受限(IUGR)的诊断价值。方法:选择2020年4月—2021年3月郑州市妇幼保健院就诊的100例孕中晚期IUGR孕妇作为研究组,另选取同期于医院产检的100例正常妊娠孕妇为对照组。应用... 目的:探讨三维能量多普勒超声技术产前定量评估对胎儿宫内生长受限(IUGR)的诊断价值。方法:选择2020年4月—2021年3月郑州市妇幼保健院就诊的100例孕中晚期IUGR孕妇作为研究组,另选取同期于医院产检的100例正常妊娠孕妇为对照组。应用三维能量多普勒超声技术(3D-PDU)定量检测两组胎儿的胎盘血管化指数(VI)、血流指数(FI)、血管化—血流指数(VFI),记录两组胎儿的静脉导管血流波形,包括二尖瓣口与三尖瓣口的舒张晚期A峰、舒张早期E峰、E/A比值及肺静脉左心房开口与下腔静脉的心室收缩期S峰、舒张期D峰、心肺收缩期A峰。结果:研究组的VI值、FI值、VFI值均显著低于对照组,差异有统计学意义(t=16.990、7.799、13.069,P<0.05)。研究组的二尖瓣口E/A比值、三尖瓣口E/A比值均显著高于对照组,二尖瓣口A峰、三尖瓣口A峰显著低于对照组,差异有统计学意义(t=5.548、5.633、7.342、9.382,P<0.05);两组胎儿的二尖瓣口及三尖瓣口E峰比较,差异无统计学意义(t=0.915、0.147,P>0.05)。研究组的肺静脉左心房开口A峰、下腔静脉A峰均显著低于对照组,差异有统计学意义(t=7.342、9.382,P<0.05);两组胎儿的肺静脉左心房开及下腔静脉S峰、D峰比较,差异无统计学意义(t=0.859、0.192,P>0.05)。结论:三维能量多普勒超声技术产前定量检测胎儿的血流参数,有利于产前良好评估胎儿的宫内情况,可作为胎儿宫内生长受限的辅助诊断手段,有利于改善临床症状及妊娠结局,减少不良妊娠的发生。 展开更多
关键词 胎儿宫内生长受限 三维能量多普勒超声技术 血流动力学 诊断价值
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2D-TVS、3D-TVS容积成像和3D-PDUS联合检查在宫腔粘连诊断中的效能 被引量:1
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作者 杨艳清 《中国民康医学》 2023年第2期150-153,共4页
目的:分析阴道二维超声(2D-TVS)、三维超声(3D-TVS)容积成像、三维能量多普勒超声(3D-PDUS)联合检查在宫腔粘连诊断中的效能。方法:选取2018年1月至2021年8月该院收治的85例疑似宫腔粘连患者进行前瞻性研究。所有患者均行2D-TVS、3D-TV... 目的:分析阴道二维超声(2D-TVS)、三维超声(3D-TVS)容积成像、三维能量多普勒超声(3D-PDUS)联合检查在宫腔粘连诊断中的效能。方法:选取2018年1月至2021年8月该院收治的85例疑似宫腔粘连患者进行前瞻性研究。所有患者均行2D-TVS、3D-TVS容积成像及3D-PDUS检查,并以宫腔镜检查诊断结果作为金标准,比较2D-TVS、3D-TVS容积成像、3D-PDUS单项及联合检查在宫腔粘连诊断中的效能。结果:宫腔镜检查诊断结果显示,85例疑似宫腔粘连患者中,阳性72例,阴性13例,其中轻度粘连35例,中度粘连24例,重度粘连13例;2D-TVS检查诊断结果显示,阳性60例,阴性25例;3D-TVS容积成像检查诊断结果显示,阳性68例,阴性17例;3D-PDUS检查诊断结果显示,阳性69例,阴性16例;联合检查诊断结果显示,阳性71例,阴性14例;联合检查诊断灵敏度、特异度、准确度、阳性预测值、阴性预测值均高于2D-TVS、3D-TVS容积成像、3D-PDUS单项检查,差异有统计学意义(P<0.05);宫腔粘连组子宫内膜厚度(ED)、子宫内膜体积(EV)、内膜区血管指数(VI)、血管血流指数(VFI)均低于宫腔正常组,差异有统计学意义(P<0.05);重度粘连组ED、EV、VI、FI、VFI水平均低于中度粘连、轻度粘连组,中度粘连组ED、EV、VI、VFI水平低于轻度粘连组,差异有统计学意义(P<0.05);中度粘连组FI水平与轻度粘连组比较,差异无统计学意义(P>0.05)。结论:2D-TVS、3D-TVS容积成像、3D-PDUS联合检查诊断宫腔粘连的灵敏度、特异度、准确度、阳性预测值、阴性预测值均高于单项检查。 展开更多
关键词 二维超声 三维超声容积成像 三维能量多普勒超声 宫腔粘连 检查 诊断 效能
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获得高分辩率谱的方法之一——消Doppler双光子光谱术
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作者 郭汝平 张建秋 《新疆农业大学学报》 CAS 1994年第3期54-59,共6页
光谱测量的精度受到Doppler线宽的制约,消除由Doppler效应引起的谱线加宽,成为获得高分辩率谱首要解决的问题.高分辩激光光谱方法很多,本文仅对双光子吸收法、作一简介,以飨读者,愿高等农业院校广大读者利用光谱术... 光谱测量的精度受到Doppler线宽的制约,消除由Doppler效应引起的谱线加宽,成为获得高分辩率谱首要解决的问题.高分辩激光光谱方法很多,本文仅对双光子吸收法、作一简介,以飨读者,愿高等农业院校广大读者利用光谱术进行生物学科的测量时,了解并重视这一方法. 展开更多
关键词 光谱 doppler线宽 分辩率 双光子吸收
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