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Impact of endoscopic ultrasound-guided radiofrequency ablation in managing pancreatic malignancy
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作者 Cosmas Rinaldi Adithya Lesmana 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第2期163-168,共6页
Pancreatic malignancy is still the most lethal gastrointestinal malignancy.It has a very poor prognosis with low survival rate.Surgery is still the main treatment option for pancreatic malignancy.Most patients already... Pancreatic malignancy is still the most lethal gastrointestinal malignancy.It has a very poor prognosis with low survival rate.Surgery is still the main treatment option for pancreatic malignancy.Most patients already have locally advanced and even late stage disease due to non-specific abdominal symptoms.Even though some cases are still suitable for surgical treatment,due to its aggressiveness adjuvant chemotherapy is becoming the standard treatment for controlling the disease.Radiofrequency ablation(RFA)is a thermal therapy that has been used as one of the standard treatments for liver malignancy.It can also be performed intraoperatively.There are several reports on percutaneous RFA treatment for pancreatic malignancy using transabdominal ultrasound and guided by computed tomography scan.However,due to its anatomical location and the risk of high radiation exposure,these methods seem to be very limited.Endoscopic ultrasound(EUS)has been widely used for pancreatic abnormality evaluation due to its ability to detect more accurately,especially small pancreatic lesions,compared to other imaging modalities.By the EUS approach,it is easier to achieve good visualization of tumor ablation and necrosis as the echoendoscope position is closer to the tumor area.Based on studies and a recent meta-analysis,EUS-guided RFA is a promising treatment approach for most pancreatic malignancy cases,but most studies only collected data from a small sample size.Larger studies are needed before clinical recommendations can be made. 展开更多
关键词 Endoscopic ultrasound Radio frequency ablation PERCUTANEOUS SURGERY Pancreatic malignancy
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High-frequency Ultrasound Evaluation of Effects of Early Treatment with Metoprolol on Myocardial Inflammatory Cytokine Expression in Rats with Acute Myocardial Infarction 被引量:4
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作者 武文 黄晓玲 +2 位作者 张江霞 高宇 杨亚利 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2012年第5期774-778,共5页
This study evaluated the effects of early treatment with β-adrenergic blocker metoprolol on ventricular remodeling and function after acute myocardial infarction (AMI) by using high frequency ultrasound.The relations... This study evaluated the effects of early treatment with β-adrenergic blocker metoprolol on ventricular remodeling and function after acute myocardial infarction (AMI) by using high frequency ultrasound.The relationship between the efficacy and the expression level of cardiac myocardial inflammatory cytokine was examined in rats.The rat model of AMI was induced by ligating the left ante-rior descending artery.The surviving rats were randomly assigned to two experimental groups:MI control (MI) group and MI metoprolol (MI-B) group,with the rats undergoing sham operation serving as normal control (Sham).MI-B group was given metoprolol for 4 weeks (refer to the CCS-2 protocol) and the other two groups received equal volume of saline via intragastric (i.g.) administation.The ventricular remodeling and function were evaluated by high frequency ultrasound 4 weeks after the treatment.Then all rats were sacrificed for pathological examination and immunohistochemistrical detection of inflammatory cytokines,including IL-1β,IL-6,IL-10 and TNF-α.Compared with the MI group,the left ventricular end-systolic dimension,end-diastolic dimension,end-systolic volume and end-diastolic volume of the MI-B group were significantly decreased (P<0.01),while the left ventricular anterior wall end-diastolic thickness,ejection fraction and fractional shortening were obviously increased (P<0.01).The conspicuous improvement in the left ventricular morphology and function was coincident with the markedly reduced TNF-α and IL-1β expression and the increased IL-10 expression.We are led to conclude that early metoprolol treatment for AMI can regulate myocardial inflammatory cytokine expression to improve cardiac function and the underlying mechanism might be that it decreases the level of pro-inflammatory cytokines and increases the level of its anti-inflammatory counterparts in cardiac myocytes.Our study also showed that echocardiography is a useful technique for the structural and functional assessment of left ventricle after acute myocardial infarction. 展开更多
关键词 high frequency ultrasound myocardial infarction METOPROLOL CYTOKINES inflammation
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A Static Bioimpedance and Dynamic Acoustic Myography Preliminary Assessment of Low Frequency Therapeutic Ultrasound Treatment of the Shoulder Muscle Trapezius: An Equine Study 被引量:1
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作者 Diane lsbell Sebastian Laguna Adrian Harrison 《Open Journal of Veterinary Medicine》 2021年第4期125-135,共11页
<strong>Background:</strong><b><span style="font-family:;" "=""> </span></b><span style="font-family:;" "="">In horses, thera... <strong>Background:</strong><b><span style="font-family:;" "=""> </span></b><span style="font-family:;" "="">In horses, therapeutic ultrasound has been shown to be beneficial for suspensory ligament injuries, and more generally to stimulate tissue repair and reduce localized pain. However, it has yet to be examined in relation to soft tissue injuries sustained during competition or in connection with rider/saddle interactions. <b>Aim: </b>The aim of the present study was to examine the efficacy of topical low-frequency therapeutic ultrasound on the shoulder muscles of injured horses. <b>Methods:</b></span><b><span style="font-family:;" "=""> </span></b><span style="font-family:;" "="">Muscle mass and cellular health was assessed for <i>M. trapezius</i> using non-invasive multi-frequency bioimpedance, and dynamic improvements in <i>M. trapezius</i> and <i>M. latissimus dorsi</i> were examined using acoustic myography (AMG). A total of 8 injured horses (painful to palpation and atrophied) were treated using an</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">EQ Pro Therapy unit, following a set protocol that comprised treatment every other day for 10 treatments. Pre-treatment values were then compared with post-treatment measurements (1 & 6 months later). </span><b><span style="font-family:;" "="">Results:</span></b><b><span style="font-family:;" "=""> </span></b><span style="font-family:;" "="">The mfBIA results for <i>M. trapezius</i> showed a significant improvement (P</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">0.05) of EQ Pro Therapy treatment for the membrane capacitance (Mc) and phase angle (PA) parameters when comparing the Pre <span>vs</span> Post</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">1 and Post</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">1 <span>vs</span> Post</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">2 measurements. Similar improvements were seen for the AMG measurements for <i>M. trapezius</i> and <i>M. latissimus dorsi</i> where statistically significant improvements in the muscle efficiency (E-score) and temporal summation (T-score) as well as the spatial summation (S-score) and mean of the ST-scores were noted</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">(P</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">0.05 to P</span><span style="font-family:;" "=""> </span><span style="font-family:;" "=""><</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">0.01).</span><span style="font-family:;" "=""> </span><b><span style="font-family:;" "="">Conclusion:</span></b><span style="font-family:;" "=""> The present findings suggest that </span><span style="font-family:;" "="">EQ Pro Therapy treatment is efficacious in terms of equine cases involving soft tissue shoulder muscle injuries (</span><span style="font-family:;" "="">painful to palpation and atrophied).</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">The main improvements noted were not only increased muscle mass and cellular health</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">but also </span><span style="font-family:;" "="">improved force production, better coordination</span><span style="font-family:;" "="">,</span><span style="font-family:;" "=""> and lateral balance, which persisted for at least six months after treatment.</span> 展开更多
关键词 Horse Skeletal Muscle Acoustic Myography Low frequency ultrasound
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Clinical Value of Transperineal 3D Volume Ultrasound Combined with 2D High Frequency Ultrasound in Anal Fistula 被引量:3
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作者 Dan Yang Xiufen Yao 《Journal of Biosciences and Medicines》 2020年第5期12-19,共8页
Objective: To explore the clinical diagnostic value of transperineal volume ultrasound combined with two-dimensional high-frequency ultrasound for anal fistula. Methods: A total of 52 patients with anal fistula admitt... Objective: To explore the clinical diagnostic value of transperineal volume ultrasound combined with two-dimensional high-frequency ultrasound for anal fistula. Methods: A total of 52 patients with anal fistula admitted to the Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine from December 2017 to July 2018 were selected. They were all undergoing transperineal 3D volume ultrasound combined with 2D high-frequency ultrasound examination, and the diagnosis results were analyzed. The results of ultrasonography and surgical pathology were compared. Results: Among 52 patients, 3D volume ultrasound combined with 2D high-frequency ultrasound were used to diagnose 32 cases of anal fistula intersphincteric type, 14 cases of transsphincter type, 5 cases of supra-sphincter type, and 1 case of extra-sphincter type. T supervisor classification accuracy rate is 90%. The detection rate of branch pipes was 92%, and the compliance rate of internal fistula was 95%. Two-dimensional high-frequency ultrasound was used to diagnose 34 cases of anal fistula intersphincteric type, 14 cases of transsphincter type, 4 cases of supra-sphincter type, and 0 cases of extra-sphincter type. The detection rate of branch canals was 42%, and the accuracy of type classification was 90%. The coincidence rate was 95%. There was a statistically significant difference in the detection rate of the anal fistula branch and the coincidence rate of the internal fistula between the two methods (both P Conclusion: 1) The overall coincidence rate of three-dimensional volumetric ultrasound combined with two-dimensional high-frequency ultrasound in the diagnosis of anal fistula is high;2) Three-dimensional volumetric ultrasound technology has great application prospects in infants and anal fistulas. 展开更多
关键词 TWO-DIMENSIONAL HIGH-frequency ultrasound Anal Fistula Three-Dimensional VOLUME ultrasound COMBINED with TWO-DIMENSIONAL HIGH-frequency ultrasound
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Application Value of High-Frequency Ultrasound and Contrast-Enhanced Ultrasound in Patients with Knee Osteoarthritis with Different TCM Syndromes 被引量:1
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作者 Yufei Wang Yingcong Xiao +5 位作者 Zhao Shen Peilu Wang He Chang Hongjuan Mao Xiufen Yao Youmin Guo 《Journal of Biosciences and Medicines》 2020年第12期149-156,共8页
<strong>Objective:</strong> To explore the application value of high-frequency ultrasound and contrast-enhanced ultrasound in different syndrome types of knee osteoarthritis, and to provide more imaging ev... <strong>Objective:</strong> To explore the application value of high-frequency ultrasound and contrast-enhanced ultrasound in different syndrome types of knee osteoarthritis, and to provide more imaging evidence for clinical diagnosis and treatment. <strong>Method:</strong> Sixty patients with KOA were selected according to TCM classification, which were mainly divided into Qi stagnation and blood stasis type and cold-dampness blockage type. All knee joints were routinely examined by high frequency ultrasound, and those with synovial hyperplasia were examined by contrast-enhanced ultrasound. High frequency ultrasound is the examination of synovium, cartilage and collateral ligament of knee joint based on two-dimensional ultrasound. Contrast-enhanced ultrasound (CEUS) refers to the contrast examination of synovium in knee joint patients with synovial hyperplasia. <strong>Result: </strong>Among them, the suprapatellar sac effusion and synovial thickening of Qi stagnation and blood stasis type were more obvious than those of cold-dampness arthralgia type (P < 0.05), and the degree of wear of the intercondylar cartilage of cold-dampness arthralgia type was more obvious than that of Qi stagnation. The blood stasis type is heavier and the meniscus bulge is higher (P < 0.05). The radiography of synovial hyperplasia showed that the area under the curve of Qi stagnation and blood stasis type was higher than that of cold dampness arthralgia type (P < 0.05), and the peak time was significantly shorter than that of cold dampness arthralgia type. There was no statistical difference in effective peak gradient and onset time of type (P > 0.05). <strong>Conclusion: </strong>To a certain extent, the high-frequency ultrasound and contrast-enhanced ultrasound performance of knee osteoarthritis can be used as a dialectical reference for different TCM syndrome types. 展开更多
关键词 Knee Osteoarthritis High-frequency ultrasound Contrast-Enhanced ultrasound Syndrome
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Breast Lump Recognition Algorithms Based on Ultrasound Radio-Frequency Signals
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作者 YAN Yu CAI Xiaowei +2 位作者 ZHU Wei CAI Runqiu WU Yiyun 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2019年第4期635-640,共6页
A method for evaluating the benign and malignant breast tumors based on radio?frequency(RF)data was explored by extracting the characteristic parameters of breast ultrasound RF signals.The breast biopsy data were used... A method for evaluating the benign and malignant breast tumors based on radio?frequency(RF)data was explored by extracting the characteristic parameters of breast ultrasound RF signals.The breast biopsy data were used as the reference data for judging the lump benign or malignant.The extracted ultrasound RF data were reconstructed and segmented by computer aided method to obtain the breast tumor region of interest(ROI)and its characteristic parameters(entropy and standard deviation).The characteristic parameters were statistically analyzed to evaluate the relationship between characteristic parameters and benign or malignant breast tumors.The results indicate the entropy and standard deviation of normal region is much higher than that of lump region,which shows that the standard deviation and entropy characteristic parameters of ultrasonic RF signals are meaningful in the diagnosis of breast tumors.The proposed method provides a new direction for computer?aided diagnosis of benign and malignant breast tumors. 展开更多
关键词 ultrasound radio‑frequency signal breast lump signal processing standard deviation ENTROPY
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Generation of Ultrasound Based on the Frequency Response Characteristics of the “Koss Pro Headphone” with R. David Case Sound Wave Files’—A Case Study
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作者 R. David Case D. Chuckravanen 《World Journal of Engineering and Technology》 2021年第2期374-383,共10页
The research aim of this work is to analyse the characteristics of R. David Case Sound waves that are posited to have positive effects on people suffering from tinnitus. Moreover, the participants who listened to thes... The research aim of this work is to analyse the characteristics of R. David Case Sound waves that are posited to have positive effects on people suffering from tinnitus. Moreover, the participants who listened to these sound wave files using specific headsets or headphones of the Koss models (ktx Pro, ksc-75) showed improved health condition such as alleviating tinnitus that they are suffering from. Therefore, these discoveries have encouraged R. David Case to pursue positively his journey into finding out what is special about those sounds when being listened specifically with Koss models. In this research, we focus mainly on the technical aspects of R. David Case sound signals which he has recorded. These specific sound waves were analysed using time domain, frequency domain as well as the effect of using the Koss Pro headphone frequency response characteristics applied to the sound. Results obtained from the analysis demonstrated that the generation of ultrasound c</span><span style="font-family:Verdana;">an</span><span style="font-family:Verdana;"> be the underlying reason for the treatment of the tin</span><span style="font-family:Verdana;">n</span><span style="font-family:Verdana;">itus. 展开更多
关键词 ultrasound TINNITUS David Case Sound Wave File frequency Analysis Healing
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High Frequency Ultrasound in Determining the Causes of Acute Shoulder Joint Pain
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作者 Mustafa Z. Mahmoud 《Open Journal of Radiology》 2016年第4期275-284,共10页
Shoulder ultrasonography is approved as the examination of choice for rotator cuff abnormality in many centers around the world since it is an inexpensive and safe tool for investigation of rotator cuff abnormalities.... Shoulder ultrasonography is approved as the examination of choice for rotator cuff abnormality in many centers around the world since it is an inexpensive and safe tool for investigation of rotator cuff abnormalities. The goal of this study was to determine the ultrasound findings in patients with acute shoulder joint pain, and also to identify possible predictors of shoulder pain, as well as to compare the ultrasound diagnostic performance to that of MRI in such condition. A total of 65 (mean age 28 ± 1.2 years) consequential patients were recruited for a period of six months between July 2015 and June 2016 in this study. Collected data were confined on age, medical history, and clinical symptoms. Shoulder ultrasound was performed with a linear array transducer (10 - 15 MHz) connected to HI vision Avius ultrasound unit;Hitachi. MRI for the shoulder joint was performed in all cases to confirm the ultrasound results, using 1.5-T MRI system (Magnetom Espree);Siemens. Statistical analysis was completed using the standard Statistical Package for the Social Sciences (SPSS Inc., Chicago, IL, USA) version 20 for windows. Ultrasound manages to determine the causes of acute shoulder joint pain in 98% of the patients. Fitted achievement values for shoulder ultrasound in the diagnosis the causes of shoulder joint pain were 100% sensitivity and a range of 96% to 100% of accuracy. Ultrasound presents a high sensitivity and accuracy in diagnosis a wide spectrum of shoulder joint lesions, with a diagnostic performance near to that of MRI. 展开更多
关键词 High frequency ultrasound Magnetic Resonance Imaging Prospective Cohort Study Rotator Cuff Shoulder Joint
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A FREQUENCY DOMAIN QUANTITATIVE MEASUREMENT METHOD FOR BLOOD FLOW VELOCITY WITH BIDIRECTIONAL DOPPLERULTRASOUND AVOIDING DOWN-BAND CHANNEL
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作者 Wang Weiqi,Shao Qianming,Yu Jianguo(Department of Electronic Engineering,Fudan University, Shanghai, 200433, China) 《Chinese Journal of Biomedical Engineering(English Edition)》 1996年第4期147-154,共8页
The up-band signal of the second ultrasonic beam contained reversecomPOnent or blooll now. Using double ultrasonic beam,bidirectional Doppler ultrasound can avoid the use or two kinds or band filters and be simplified... The up-band signal of the second ultrasonic beam contained reversecomPOnent or blooll now. Using double ultrasonic beam,bidirectional Doppler ultrasound can avoid the use or two kinds or band filters and be simplified into a singlekind or band filter. In order to make the output more accurate,the inrluence of angle effect can be overcome by the table-out method and another special methodcalled cose recorrection.The experiment result is that when the deviation angle varies from-- 18' to +20' the relative error or output is less than 5%. 展开更多
关键词 ultrasound BLOOD FLOW VELOCITY frequency separation Down-bandchannel
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The High Frequency (HF) Ultrasound as a Useful Imaging Technique for the Efficacy Assessment of Different Anti-Cellulite Treatments
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作者 Mlosek Robert Krzysztof Malinowska Sylwia +2 位作者 Debowska Renata Lewandowski Marcin Nowicki Andrzej 《Journal of Cosmetics, Dermatological Sciences and Applications》 2013年第1期90-98,共9页
The purpose of the research was to evaluate the role of high frequency ultrasound in monitoring and efficacy assessment of anti-cellulite treatments. A group of 66 women used 3 different types of anti-cellulite treatm... The purpose of the research was to evaluate the role of high frequency ultrasound in monitoring and efficacy assessment of anti-cellulite treatments. A group of 66 women used 3 different types of anti-cellulite treatments;additionally a placebo group (n = 18) was created. The μ-Scan ultrasound device with a 35 MHz mechanical probe was used for the examinations. The following parameters were subjected to the ultrasound evaluation: epidermis thickness, dermis thickness, dermis echogenicity, the length and area of subcutaneous tissue bands projecting into the dermis (dermis-hypodermis junction), as well as the presence/absence of edema within the dermis. As a result of anti-cellulite treatment, the length and area of dermis-hypodermis junction significantly decreased, and dermis echogenicity significantly increased. Ultrasound imaging made it possible to evaluate the efficacy of the applied treatments. The high frequency ultrasound is a useful imaging technique for the application in aesthetic dermatology and cosmetology. 展开更多
关键词 Aesthetic Medicine CELLULITE Anti-Cellulite Treatment High frequency ultrasound Skin ultrasound
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Development of a High-frequency Ultrasound System for High-speed Image Scanning 被引量:1
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作者 WU Jian-xing CHEN Pei-zhan +2 位作者 WANG Jian-lin CHEN Guan-chun CHEN Tai-song 《Chinese Journal of Biomedical Engineering(English Edition)》 2013年第2期79-85,92,共8页
High-frequency image technique has been widely applied in medical diagnosis recently. For high voltage protection, high speed stage and trigger control circuitry are difficult to implement a high-frequency ultrasound ... High-frequency image technique has been widely applied in medical diagnosis recently. For high voltage protection, high speed stage and trigger control circuitry are difficult to implement a high-frequency ultrasound imaging system. In this study, we utilized a linear servo with high noise tolerance and a novel multi-depth expression method to overcome those issues in developed high-speed image system. B-mode image of the chicken phantom by 25 MHz transducer shows the resolution of lateral and axial resolutions are up to 123 μm and 59 μm respectively. In addition, the experiment demonstrates that the axial resolution and depth of field (DOF) can be improved by time gain compensation(TGC) and multi-depth method. The results indicate that the proposed system could achieve over 24 fps for 1 mm scan distance and 100 lines per frame. In the future, the developed system is potential for other clinical applications such as ophthalmology and dermatology. 展开更多
关键词 high-frequency ultrasound time gain compensation (TGC) multi-focus scan
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A Flexible and High Speed Digital Scan Converter for High Frequency Ultrasound Imaging
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作者 QIU Wei-bao YU Yan-yan SUN Lei 《Chinese Journal of Biomedical Engineering(English Edition)》 2011年第3期109-114,共6页
This paper presents a flexible and high speed digital scan converter (DSC) with the ability to handle high frequency ultrasound imaging in real-time. The characteristics in imaging system such as focus length of trans... This paper presents a flexible and high speed digital scan converter (DSC) with the ability to handle high frequency ultrasound imaging in real-time. The characteristics in imaging system such as focus length of transducer, the swing radius and sampling length etc. could be changed easily in compliance with the researcher's application based on this flexible digital scan converter. Linear interpolation is employed to achieve the coordinate transformations algorithm. Custom-built software is programmed to preliminarily handle the algorithm according to different ultrasound imaging applications. High performance FPGA will implement high speed interpolation calculation based on the preliminary data which are stored in the DDR2 SDRAM from the software. 64 bit 66 MHz PCI is employed to accomplish high speed data transmission. Experiment has shown that more than 500 frame rate could be achieved based on this high speed digital scan converter. The designed flexible and high speed digital scan converter could be used in current FPGA based high frequency ultrasound imaging system. 展开更多
关键词 flexible digital scan conversion high frequency ultrasound imaging FPGA
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Dual Treatment Strategy by Venous Ulcers: Pilot Study to Dual-Frequency Ultrasound Application
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作者 Ilja Kruglikov Ekaterina Kruglikova 《Journal of Cosmetics, Dermatological Sciences and Applications》 2011年第4期157-163,共7页
We propose a new dual treatment strategy by venous ulcer, consisting in simultaneous modulation of matrix metalloproteinases (MMPs) and heat shock proteins (HSPs) in the wound. One treatment method which can efficient... We propose a new dual treatment strategy by venous ulcer, consisting in simultaneous modulation of matrix metalloproteinases (MMPs) and heat shock proteins (HSPs) in the wound. One treatment method which can efficiently modulate both these substances is based on the application of dual-frequency ultrasound (LDM). This strategy was checked in a pilot study on 10 patients with chronic venous ulcers and demonstrated excellent healing rate. 展开更多
关键词 VENOUS ULCER DUAL-frequency ultrasound Matrix METALLOPROTEINASES Heat Shock PROTEINS
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High frequency components in avian vocalizations
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作者 李建强 张雁云 张正旺 《Chinese Birds》 2011年第3期125-131,共7页
Ultrasonic communication in vertebrates is attracting increasing research interest.To determine if ultrasonic vocalization is common in birds,we recorded their vocalizations with ultrasound detectors in the Dongzhai N... Ultrasonic communication in vertebrates is attracting increasing research interest.To determine if ultrasonic vocalization is common in birds,we recorded their vocalizations with ultrasound detectors in the Dongzhai National Nature Reserve of Henan Province,China.We found varying degrees of high frequency components in the vocalizations of 14 species and in several of these species,the frequency of harmonics was up to the range of ultrasound.We suggest that more studies are required to determine whether the high frequency components in avian vocalizations have functions and what these functions are.In addition,the ability of birds to hear sounds in the high frequency range also requires re-examination. 展开更多
关键词 avian vocalization high frequency components ultrasound FUNCTIONS
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Reference values of carotid intima-media thickness and arterial stiffness in Chinese adults based on ultrasound radio frequency signal:A nationwide,multicenter study
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作者 Changyang Xing Xiujing Xie +28 位作者 Yu Wu Lei Xu Xiangping Guan Fan Li Xiaojun Zhan Hengli Yang Jinsong Li Qi Zhou Yuming Mu Qing Zhou Yunchuan Ding Yingli Wang Xiangzhu Wang Yu Zheng Xiaofeng Sun Hua Li Chaoxue Zhang Cheng Zhao Shaodong Qiu Guozhen Yan Hong Yang Yinjuan Mao Weiwei Zhan Chunyan Ma Ying Gu Wu Chen Mingxing Xie Tianan Jiang Lijun Yuan 《Chinese Medical Journal》 SCIE CAS CSCD 2024年第15期1802-1810,共9页
Background:Carotid intima-media thickness(IMT)and diameter,stiffness,and wave reflections,are independent and important clinical biomarkers and risk predictors for cardiovascular diseases.The purpose of the present st... Background:Carotid intima-media thickness(IMT)and diameter,stiffness,and wave reflections,are independent and important clinical biomarkers and risk predictors for cardiovascular diseases.The purpose of the present study was to establish nationwide reference values of carotid properties for healthy Chinese adults and to explore potential clinical determinants.Methods:A total of 3053 healthy Han Chinese adults(1922 women)aged 18-79 years were enrolled at 28 collaborating tertiary centers throughout China between April 2021 and July 2022.The real-time tracking of common carotid artery walls was achieved by the radio frequency(RF)ultrasound system.The IMT,diameter,compliance coefficient,βstiffness,local pulse wave velocity(PWV),local systolic blood pressure,augmented pressure(AP),and augmentation index(AIx)were then automatically measured and reported.Data were stratified by age groups and sex.The relationships between age and carotid property parameters were analyzed by Jonckheere-Terpstra test and simple linear regressions.The major clinical determinants of carotid properties were identified by Pearson’s correlation,multiple linear regression,and analyses of covariance.Results:All the parameters of carotid properties demonstrated significantly age-related trajectories.Women showed thinner IMT,smaller carotid diameter,larger AP,and AIx than men.Theβstiffness and PWV were significantly higher in men than women before forties,but the differences reversed after that.The increase rate of carotid IMT(5.5µm/year in women and 5.8µm/year in men)and diameter(0.03 mm/year in both men and women)were similar between men and women.For the stiffness and wave reflections,women showed significantly larger age-related variations than men as demonstrated by steeper regression slopes(all P for age by sex interaction<0.05).The blood pressures,body mass index(BMI),and triglyceride levels were identified as major clinical determinants of carotid properties with adjustment of age and sex.Conclusions:The age-and sex-specific reference values of carotid properties measured by RF ultrasound for healthy Chinese adults were established.The blood pressures,BMI,and triglyceride levels should be considered for clinical application of corresponding reference values. 展开更多
关键词 Intima-media thickness Arterial stiffness Reference values ultrasound radio frequency signal Wave reflections
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Influence enhancement effect of bi-frequency ultrasonic irradiation by TA fluorescence method
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作者 FAN Xinnan~(1,2), ZHU Changping~(1,2), FENG Ruo~(2,1), WANG Yuming~3, He Shichuan~1 (1 Department of Computer & Information Engineering, Hohai University, Changzhou 210032, China) (2 Institute of Acoustics, Nanjing University, Nanjing 210093, China) (3 Changzhou College of Mechanical and Electrical Engineering, Changzhou 210032, China) 《声学技术》 CSCD 2004年第S1期36-38,共3页
Based on a previous research of cavitation effect under bi-frequency ultrasound irradiation, this paper studies bi-frequency irradiations with similar experimental settings. The additional irradiation sources with fre... Based on a previous research of cavitation effect under bi-frequency ultrasound irradiation, this paper studies bi-frequency irradiations with similar experimental settings. The additional irradiation sources with frequencies of 1.04MHz, 0.8MHz and 1.7MHz are individually combined with the main ultrasonic irradiation source with frequency of 28kHz to form bi-frequency ultrasonic irradiation. The intensity of 28kHz irradiation was fixed at 12.5W/cm^2, while the intensity of the ultrasound at the other three frequencies is varied from1 W/cm^2 to 18 W/cm^2. It turns out that under the influence of the bi-frequency irradiation, the fluorescence intensity is obviously greater than the sum of those at individual frequencies. So the frequency of the additional sonication strikingly influences the fluorescence enhancement effect. For example, the fluorescence enhancement effect of 1.04MHz is stronger than that of 1.7MHz, and the enhancement effect of 0.8MHz is further stronger than that of 1.04MHz. Under the sonic intensity of (7.9)W/cm^2, the fluorescence intensity of 1.04MHz is approximately twice that of 1.7MHz while the fluorescence intensity of 0.8MHz is approximately 1.5 times that of 1.04MHz. 展开更多
关键词 TA FLUORESCENCE method TEREPHTHALATE frequency effect bi-frequency ultrasound.
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高频超声在构建SD大鼠皮下移植性乳腺癌模型中的应用 被引量:1
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作者 潘福治 叶冬熳 +1 位作者 郑华川 于韬 《现代肿瘤医学》 CAS 2024年第8期1393-1396,共4页
目的:应用MADB-106大鼠乳腺癌细胞悬液皮下移植法建立SD大鼠乳腺癌移植性肿瘤动物模型,并使用高频超声监测肿瘤生长情况。方法:选取7~8周龄雌性SD乳鼠16只,将处于对数生长期的MADB-106大鼠乳腺癌细胞悬液于大鼠腹股沟皮下接种,应用高频... 目的:应用MADB-106大鼠乳腺癌细胞悬液皮下移植法建立SD大鼠乳腺癌移植性肿瘤动物模型,并使用高频超声监测肿瘤生长情况。方法:选取7~8周龄雌性SD乳鼠16只,将处于对数生长期的MADB-106大鼠乳腺癌细胞悬液于大鼠腹股沟皮下接种,应用高频超声观察成瘤率、肿块大小、血供情况及其它声像图特征。结果:SD大鼠接种成功率为100%,死亡2只,剩余14只生长良好;超声检查肿块为类圆形,内部低回声且稍不均匀,边界尚清,后方回声衰减,彩色多普勒扫查肿块内部及周边可见较丰富血流信号;3周后切除瘤体组织,大体观肿块成灰白色,多呈椭圆形,部分边缘呈分叶状改变,肿瘤血管较丰富,镜下可见肿瘤细胞大小形状各异,核大深染,异型性明显。结论:通过MADB-106大鼠乳腺癌细胞接种于雌性SD大鼠腹股沟皮下,成功建立了大鼠乳腺癌移植性肿瘤动物模型。高频超声技术可以在SD大鼠乳腺癌皮下成瘤过程中对肿物的大小、形态、边界、内部回声及血流等生物学情况进行动态检测,是观察和评价瘤体动态变化过程的重要技术手段。 展开更多
关键词 大鼠乳腺癌 MADB-106细胞株 移植动物模型 高频超声
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当前不同去肾神经术的特点和存在的问题
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作者 亢园园 罗淞元 +2 位作者 许建忠 罗建方 卢成志 《心血管病学进展》 CAS 2024年第10期875-879,884,共6页
多个国家临床指南和专家共识均指出,经导管肾动脉消融去肾神经术(RDN)治疗高血压是除了改善生活方式和药物治疗以外第三种抗高血压治疗方法。射频、超声、乙醇等多种不同方式的RDN器械被研发并开展了系列临床研究。现将详细分析这些不同... 多个国家临床指南和专家共识均指出,经导管肾动脉消融去肾神经术(RDN)治疗高血压是除了改善生活方式和药物治疗以外第三种抗高血压治疗方法。射频、超声、乙醇等多种不同方式的RDN器械被研发并开展了系列临床研究。现将详细分析这些不同RDN消融技术的基本特性、临床研究结果及存在的问题和争议,并对未来的发展方向进行探讨。 展开更多
关键词 去肾神经术 射频 超声 高血压
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用于血管内超声成像的高频换能器研制
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作者 李霞 陈益良 苏敏 《声学技术》 CSCD 北大核心 2024年第1期142-146,共5页
血管内超声(Intravascular Ultrasound,IVUS)成像技术可以精确评估血管腔口径、血管壁形态和其他相关血流和血管特性,在冠状动脉疾病的诊断、治疗指导和治疗后的评估中发挥着重要作用。文章设计并制备了一种用于血管内超声成像的高频超... 血管内超声(Intravascular Ultrasound,IVUS)成像技术可以精确评估血管腔口径、血管壁形态和其他相关血流和血管特性,在冠状动脉疾病的诊断、治疗指导和治疗后的评估中发挥着重要作用。文章设计并制备了一种用于血管内超声成像的高频超声换能器,并对换能器的电学和声学性能进行测试和表征。结果表明,所制备IVUS换能器的中心频率为38.9 MHz,-6 dB相对带宽为56.6%,在谐振频率42.3 MHz处的电阻抗为22.6Ω,在反谐振频率48.2MHz处的电阻抗为56.5Ω,有效机电耦合系数为0.48。使用该换能器进行线仿体成像实验的结果显示,换能器的纵向分辨率为54μm,横向分辨率为209μm。最后,将文中制备的超声换能器与国外同类型换能器进行比较,结果表明,该换能器的性能良好,能够满足血管内超声临床检测需求,未来有望能够突破技术瓶颈,实现国产替代。 展开更多
关键词 心血管疾病 血管内超声成像 高频超声换能器
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高频超声检查和剪切波弹性成像在尿毒症周围神经病变中的诊断价值研究
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作者 张兆光 徐慧颖 +4 位作者 李璇 刘静 孙昊琦 陈学勋 董晓红 《医学影像学杂志》 2024年第8期115-118,123,共5页
目的 探讨高频超声检查和剪切波弹性成像在尿毒症周围神经病变中的诊断价值。方法 选取我院收治的尿毒症患者96例,其中伴周围神经病变患者46例(UPN组),不伴周围神经病变患者50例(NUPN组),以及同期健康体检者40例(对照组)。三组均进行年... 目的 探讨高频超声检查和剪切波弹性成像在尿毒症周围神经病变中的诊断价值。方法 选取我院收治的尿毒症患者96例,其中伴周围神经病变患者46例(UPN组),不伴周围神经病变患者50例(NUPN组),以及同期健康体检者40例(对照组)。三组均进行年龄、性别、病史时长、实验室检查、电生理等指标检测,同时行双侧胫神经高频超声检查探查及剪切波弹性成像测量胫神经横截面积(CSA)、杨氏模量(Emean)、长径、宽径、周长,绘制受试者工作特征曲线(ROC),评价各项指标的诊断效能。结果 与对照组比较,UPN组与NUPN组血肌酐、血尿素氮、血磷浓度显著升高,而白蛋白显著降低,差异有统计学意义(P<0.05);与NUPN组比较,UPN组病史时长、β_2-微球蛋白、甲状旁腺素(PTH)、血钾浓度、血磷浓度均显著升高,而血红蛋白、白蛋白、血钠浓度均显著下降,差异有统计学意义(P<0.05)。三组胫神经测量值组间比较,UPN组测得胫神经的Emean、CSA、周长等均高于NUPN组及对照组,差异有统计学意义(P<0.05);测得三组样本胫神经的Emean、CSA、周长的曲线下面积(AUC)分别为0.899、0.675、0.582,最佳截断值分别为55.56 kPa、0.23 cm~2、1.91 cm。结论 高频超声检查和剪切波弹性成像在尿毒症周围神经病变中具有较好的诊断价值,可作为临床尿毒症周围神经病变的诊断和监测手段。 展开更多
关键词 尿毒症周围神经病变 胫神经 杨氏模量 高频超声检查 剪切波弹性成像
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