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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:14
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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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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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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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Optimization of three-dimensional boiling enhancement structure at evaporation surface for high power light emitting diode 被引量:2
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作者 Jian-hua XIANG Chao ZHOU +3 位作者 Chun-liang ZHANG Gui-yun LIU Cong-gui CHEN Wei ZHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第7期1405-1413,共9页
A theoretical model of phase change heat sink was established in terms of thermal resistance network. The influence of different parameters on the thermal resistance was analyzed and the crucial impact factors were de... A theoretical model of phase change heat sink was established in terms of thermal resistance network. The influence of different parameters on the thermal resistance was analyzed and the crucial impact factors were determined. Subsequently, the forming methods including ploughing-extrusion and stamping method of boiling enhancement structure at evaporation surface were investigated, upon which three-dimensional microgroove structure was fabricated to improve the efficiency of evaporation. Moreover, the crucial parameters related to the fabrication of miniaturized phase change heat sink were optimized. The heat transfer performance of the heat sink was tested. Results show that the developed phase change heat sink has excellent heat transfer performance and is suitable for high power LED applications. 展开更多
关键词 high power LED phase change heat sink ploughing-extrusion boiling enhancement three-dimensional microgroove
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Roughness evaluation of three-dimensional asphalt pavement based on two-dimensional power spectral density 被引量:2
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作者 Ding Zhike Xu Feiyun Zhao Xun 《Journal of Southeast University(English Edition)》 EI CAS 2022年第4期401-407,共7页
To solve the problem of the lack of comprehensive evaluation of three-dimensional(3D)asphalt pavement roughness,a method for evaluating the asphalt pavement roughness is proposed based on two-dimensional(2D)power spec... To solve the problem of the lack of comprehensive evaluation of three-dimensional(3D)asphalt pavement roughness,a method for evaluating the asphalt pavement roughness is proposed based on two-dimensional(2D)power spectral density(PSD).By calculating the 2D PSD of a 3D asphalt pavement and converting it into the longitudinal average asphalt pavement PSD,the relationship between the evaluation method of the 3D asphalt pavement roughness and the current evaluation standard of roughness is established.Combined with the road-fitting formula used in international standards,the elevation data of the A,B,C,and D grades of the 3D asphalt pavement are simulated by the harmonic superposition method.According to the proposed method,the longitudinal PSD of each level of simulated asphalt pavement is calculated and compared with the standard spectral line of each pavement level.This approach verifies the effectiveness of the proposed method in evaluating the roughness of the 3D asphalt pavement.Compared with the PSD of a certain horizontal profile elevation,it is verified that the fluctuation amplitude of the spectral line calculated by the proposed method is greatly improved.The results show that the proposed method can evaluate the roughness of asphalt pavements more comprehensively and accurately and has strong practicability. 展开更多
关键词 ROUGHNESS power spectral density three-dimensional asphalt pavement
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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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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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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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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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Optimization of Wireless Power Receiving Coil for Near-Infrared Capsule Robot
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作者 WANG Wei ZHOU Cheng +3 位作者 JIANG Jinlei CUI Xinyuan YAN Guozheng CUI Daxiang 《Journal of Shanghai Jiaotong university(Science)》 2025年第3期425-432,共8页
An optimizing method for designing the wireless power receiving coil(RC)is proposed in this paper to address issues such as insufficient and fluctuating power supply in the near-infrared capsule robot.An elec-tromagne... An optimizing method for designing the wireless power receiving coil(RC)is proposed in this paper to address issues such as insufficient and fluctuating power supply in the near-infrared capsule robot.An elec-tromagnetic and circuit analysis is conducted to establish the magnetic induction intensity and equivalent circuit models for the wireless power transmission system.Combining these models involves using the number of layers in each dimension as the optimization variable.Constraints are imposed based on the normalized standard deviation of the receiving-end load power and spatial dimensions.At the same time,the optimization objective aims to maximize the average power of the receiving-end load.This process leads to formulating an optimization model for the RC.Finally,three-dimensional RCs with three different sets of parameters are wound,and the receiving-end load power of these coils is experimentally tested under various drive currents.The experimental values of the receiving-end load power exhibit a consistent trend with theoretical values,with experimental values consistently lower than theoretical values.The optimized coil parameters are determined by conducting comparative exper-iments,with a theoretical value of 4.6%for the normalized standard deviation of the receiving-end load power and an average experimental value of 9.6%.The study addressed the power supply issue of near-infrared capsule robots,which is important for early diagnosing and treating gastrointestinal diseases. 展开更多
关键词 near-infrared capsule robot fuorescence imaging wireless power transmission three-dimensional receiving coil design and optimization
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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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超微血管成像血流检测在痛风性关节炎的临床应用价值
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作者 卢建明 田锦 +2 位作者 孙艳娟 武雅婷 常瑞姣 《宁夏医学杂志》 2025年第2期135-138,共4页
目的探讨超声结合超微血管成像血流检测在痛风性关节炎的临床应用价值。方法收集痛风患者85例,分别进行超声检查,对探测到的痛风石及增生滑膜进行能量多普勒及肌骨超声结合超微血管成像血流检测并将血流行半定量分级(0~3级)。结果不同hs... 目的探讨超声结合超微血管成像血流检测在痛风性关节炎的临床应用价值。方法收集痛风患者85例,分别进行超声检查,对探测到的痛风石及增生滑膜进行能量多普勒及肌骨超声结合超微血管成像血流检测并将血流行半定量分级(0~3级)。结果不同hs-CRP水平的患者超声检查出滑膜增生、关节积液、双轨征、痛风石、骨侵蚀及聚集体比较差异无统计学意义(P>0.05);血清尿酸增高组与正常组PDI和SMI血流检出率差异无统计学意义(P>0.05);SMI在血流半定量0、1级检出血流相当或低于PDI,血流半定量2级、3级高于PDI,血流检出及分级SMI优于PDI(P<0.05);hs-CRP明显增高组SMI血流高分级较轻度增高组和正常组明显增多(P<0.05);hs-CRP与增生滑膜PDI分级、滑膜增生程度分级的相关性相比,hs-CRP与滑膜增生SMI血流分级相关性最好(r=0.546)。结论SMI在检测痛风患者痛风石与增生滑膜内的血流信号较PDI更为敏感,SMI对痛风性关节炎患者增生滑膜血流检测及血流分级,可以作为评估其活动性的一项指标,hs-CRP与SMI血流对痛风的发作频率有一定的预测作用。 展开更多
关键词 痛风性关节炎 肌骨超声 能量多普勒 超微血管成像
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Comparison of three diagnostic imaging modalities for use in diabetic inferior arterial lesions
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作者 Ying Bo Jia Xie +3 位作者 Fan Xu Guo Yang Dong-Ling Li Xiao-Hang Yan 《World Journal of Diabetes》 2025年第7期217-226,共10页
BACKGROUND Underdiagnosis of peripheral arterial disease results in inadequate treatment and more serious consequences.Hence,clinicians have focused on early diagnosis and treatment.AIM To investigate the effectivenes... BACKGROUND Underdiagnosis of peripheral arterial disease results in inadequate treatment and more serious consequences.Hence,clinicians have focused on early diagnosis and treatment.AIM To investigate the effectiveness of the combination of doppler ultrasonography(DUS),three-dimensional dynamic contrast-enhanced magnetic resonance an-giography(CE-MRA),and CT angiography(CTA)in assessing lower extremity arterial disease in diabetes mellitus(DM).METHODS This study retrospectively analyzed the imaging and clinical data of 116 patients diagnosed with DM complicated with lower extremity vascular diseases from January 2021 to June 2023.All patients underwent unilateral or bilateral DUS,CTA,and CE-MRA as well as invasive digital subtraction angiography(DSA).The application values of DUS,CE-MRA,and CTA were compared.RESULTS A total of 152 lower extremity arteries in the 116 patients were graded following the classification of vascular branches.The Kappa values between DUS and DSA were 0.780,0.755,and 0.806 for diagnosing moderate stenosis and 0.484,0.699,and 0.449 for severe stenosis of grade 1 arteries,grade 2 arteries,and grade 3 arteries,respectively.The Kappa values between CE-MRA and DSA were 0.784,0.814,and 0.835 for diagnosing moderate stenosis and 0.694,0.748,and 0.606 for severe stenosis of grade 1 arteries,grade 2 arteries,and grade 3 arteries,respectively.The Kappa values between CTA and DSA were 0.900,0.858,and 0.878 for diagnosing moderate stenosis and 0.882,0.823,and 0.756 for severe stenosis of grade 1 arteries,grade 2 arteries,and grade 3 arteries,respectively.CONCLUSION DUS,CE-MRA,and CTA demonstrated comparable accuracy in diagnosing lower extremity arterial disease in DM,and the consistency between CTA and DSA diagnoses was higher than the other two imaging methods. 展开更多
关键词 doppler ultrasonography three-dimensional dynamic contrast-enhanced magnetic resonance angiography Computerized tomography angiography Diabetes Lower-extremity arterial disease
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测风激光雷达远距离测量技术及应用
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作者 王改利 杨亮亮 +5 位作者 陈沛 范梦奇 马丽 郝勇 秦胜光 王琪超 《气象科技》 2025年第4期457-467,共11页
测风激光雷达具备高时空分辨率和非接触式测量的能力,对于森林火灾的防控和救援具有重要意义。然而,现有测风激光雷达探测距离难以满足森林草原火灾现场对远距离风场监测的需求。为此,本文从大功率激光发射技术与晴空弱信号算法两个方... 测风激光雷达具备高时空分辨率和非接触式测量的能力,对于森林火灾的防控和救援具有重要意义。然而,现有测风激光雷达探测距离难以满足森林草原火灾现场对远距离风场监测的需求。为此,本文从大功率激光发射技术与晴空弱信号算法两个方面展开研究,提出了大功率激光发射与噪声抑制技术,开发了基于激光雷达频谱信号的弱信号风速精度优化算法,从硬件技术与数据处理两方面实现了探测距离的综合提升。研究结果表明,采用上述技术和算法后测风激光雷达可以实现15 km的大范围风场测量,在12600 m处的数据获取率超过90%;与测风塔进行对比,探测精度具有很好的一致性,水平风速和风向的决定系数均在0.99以上,风速平均偏差在0.05 m/s以下,风向平均偏差在2°以下。 展开更多
关键词 森林火灾 三维风场探测 测风激光雷达 激光大功率发射技术 弱信号处理算法
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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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应用于5.8 GHz多普勒雷达的高性能接收机
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作者 毛励剑 崔杰 +1 位作者 阮颖 陈磊 《微电子学》 北大核心 2025年第4期579-584,共6页
针对5.8 GHz多普勒雷达应用,使用HL 55 nm CMOS工艺设计了一种高性能接收机电路,接收机主要由跨导低噪声放大器(LNTA)、混频器(MIXER)、本振缓冲器(LO Buffer)以及跨阻放大器(TIA)组成。该接收机输入使用变压器巴伦实现单端转差分以获... 针对5.8 GHz多普勒雷达应用,使用HL 55 nm CMOS工艺设计了一种高性能接收机电路,接收机主要由跨导低噪声放大器(LNTA)、混频器(MIXER)、本振缓冲器(LO Buffer)以及跨阻放大器(TIA)组成。该接收机输入使用变压器巴伦实现单端转差分以获得良好共模噪声抑制,LNTA采用了辅助支路噪声抵消技术实现了低噪声,同时也具有低功耗、无电感、高输出阻抗的特点;系统层面上,使用占空比的方式,令模块进行工作休眠以实现极低功耗。后仿真结果显示,在无本振泄漏情况下,接收机整体在50 Hz处中频的噪声系数(NF)为27 dB,转换增益为41 dB;接收机整体输入1 dB压缩点(IP1dB)为-28 dBm。连续模式下,接收机功耗为4.75mW,低功耗模式下,功耗仅为23.76μW。测试结果显示,接收机在1 MHz处的噪声系数最低为26.2 dB,增益最高为41.6 dB,版图面积仅为680μm×384μm。 展开更多
关键词 多普勒雷达 低功耗 跨阻放大器 CMOS 巴伦
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多模态超声在老年人肌少症筛检中的应用价值研究
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作者 胡静怡 宋馨 +6 位作者 谢峥 周蓓 刘佳 邓学东 周培莹 莫丽亚 吴永华 《医学新知》 2025年第6期657-664,共8页
目的应用多模态超声评估老年人骨骼肌的肌肉质量、弹性硬度和血流灌注情况,分析其对肌少症的诊断价值。方法选取60岁以上肌少症患者和健康老年人作为肌少症组和对照组,分别使用肌骨超声、声触诊组织成像量化技术和能量多普勒超声对双侧... 目的应用多模态超声评估老年人骨骼肌的肌肉质量、弹性硬度和血流灌注情况,分析其对肌少症的诊断价值。方法选取60岁以上肌少症患者和健康老年人作为肌少症组和对照组,分别使用肌骨超声、声触诊组织成像量化技术和能量多普勒超声对双侧肱二头肌和股直肌进行肌肉厚度、截面积、剪切波速度以及血流能量信号进行测量和评分,并参照双能X射线吸收法(dual energy X-ray absorptiometry,DEXA)的相对骨骼肌质量指数结果,分析多模态超声参数对肌少症的诊断价值。结果共纳入73例研究对象,其中肌少症组36例、对照组37例。肌少症组的年龄、肱二头肌和股直肌剪切波速度显著高于对照组(P<0.05);肱二头肌和股直肌厚度、截面积、血流能量信号评分显著低于对照组(P<0.05)。各多模态超声参数中,肌肉的剪切波速度诊断效能最佳,其中肱二头肌剪切波速度的受试者工作特征曲线的曲线下面积(area under curve,AUC)为0.96[95%CI(0.87,0.98)],诊断肌少症的敏感度和特异度分别为86.50%和98.89%;股直肌剪切波速度的AUC为0.91[95%CI(0.84,0.95)],敏感度和特异度分别为81.08%和90.38%。肱二头肌和股直肌厚度、截面积、血流能量信号评分与DEXA结果呈正相关,剪切波速度与DEXA结果呈负相关。结论多模态超声技术可评估老年人四肢骨骼肌的形态结构学、生物力学和微循环状态,对肌少症有良好的诊断价值,为肌少症的早期筛检提供客观、多维度的量化诊断指标。 展开更多
关键词 肌少症 多模态超声 肌骨超声 声触诊组织成像量化技术 能量多普勒超声 诊断
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