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Low-intensity pulsed ultrasound reduces alveolar bone resorption during orthodontic treatment via Lamin A/C-Yes-associated protein axis in stem cells 被引量:1
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作者 Tong Wu Fu Zheng +7 位作者 Hong-Yi Tang Hua-Zhi Li Xin-Yu Cui Shuai Ding Duo Liu Cui-Ying Li Jiu-Hui Jiang Rui-Li Yang 《World Journal of Stem Cells》 SCIE 2024年第3期267-286,共20页
BACKGROUND The bone remodeling during orthodontic treatment for malocclusion often requires a long duration of around two to three years,which also may lead to some complications such as alveolar bone resorption or to... BACKGROUND The bone remodeling during orthodontic treatment for malocclusion often requires a long duration of around two to three years,which also may lead to some complications such as alveolar bone resorption or tooth root resorption.Low-intensity pulsed ultrasound(LIPUS),a noninvasive physical therapy,has been shown to promote bone fracture healing.It is also reported that LIPUS could reduce the duration of orthodontic treatment;however,how LIPUS regulates the bone metabolism during the orthodontic treatment process is still unclear.AIM To investigate the effects of LIPUS on bone remodeling in an orthodontic tooth movement(OTM)model and explore the underlying mechanisms.METHODS A rat model of OTM was established,and alveolar bone remodeling and tooth movement rate were evaluated via micro-computed tomography and staining of tissue sections.In vitro,human bone marrow mesenchymal stem cells(hBMSCs)were isolated to detect their osteogenic differentiation potential under compression and LIPUS stimulation by quantitative reverse transcription-polymerase chain reaction,Western blot,alkaline phosphatase(ALP)staining,and Alizarin red staining.The expression of Yes-associated protein(YAP1),the actin cytoskeleton,and the Lamin A/C nucleoskeleton were detected with or without YAP1 small interfering RNA(siRNA)application via immunofluorescence.RESULTS The force treatment inhibited the osteogenic differentiation potential of hBMSCs;moreover,the expression of osteogenesis markers,such as type 1 collagen(COL1),runt-related transcription factor 2,ALP,and osteocalcin(OCN),decreased.LIPUS could rescue the osteogenic differentiation of hBMSCs with increased expression of osteogenic marker inhibited by force.Mechanically,the expression of LaminA/C,F-actin,and YAP1 was downregulated after force treatment,which could be rescued by LIPUS.Moreover,the osteogenic differentiation of hBMSCs increased by LIPUS could be attenuated by YAP siRNA treatment.Consistently,LIPUS increased alveolar bone density and decreased vertical bone absorption in vivo.The decreased expression of COL1,OCN,and YAP1 on the compression side of the alveolar bone was partially rescued by LIPUS.CONCLUSION LIPUS can accelerate tooth movement and reduce alveolar bone resorption by modulating the cytoskeleton-Lamin A/C-YAP axis,which may be a promising strategy to reduce the orthodontic treatment process. 展开更多
关键词 Low-intensity pulsed ultrasound Bone resorption OSTEOGENESIS Cytoskeleton-Lamin A/C-Yes-associated protein axis Bone marrow mesenchymal stem cells Orthodontic tooth movement
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Effect of low intensity pulsed ultrasound on expression of TIMP-2 in serum and expression of mmp-13 in articular cartilage of rabbits with knee osteoarthritis 被引量:14
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作者 Jing-Bo Ji Xue-Fu Li +2 位作者 Lei Liu Guang-Zhong Wang Xin-Feng Yan 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第12期1014-1019,共6页
Objective:To study the effect of low intensity pulsed ultrasound(LIPUS) on the expression of tissue inhibitor of metalloproteinase-2(TIMP-2) in the serum and expression of matrix metallopeptidase 13(MMP-13) in the art... Objective:To study the effect of low intensity pulsed ultrasound(LIPUS) on the expression of tissue inhibitor of metalloproteinase-2(TIMP-2) in the serum and expression of matrix metallopeptidase 13(MMP-13) in the articular cartilage cells of rabbits with knee osteoarthritis(OA).Methods:Inner patellar ligament defect method was used to establish the model of knee OA.Four weeks after the modeling,the arterial blood was drawn from the ear of each rabbit,while ELISA was employed to detect the expression of TIMP-2 in the serum.The chondrocytes were separated from animals in each group and then cultured in vitro.All rabbits were divided into control group,OA model group and OA + LIPUS group.Cells in the control and OA groups were not treated,while cells in the OA+ LIPUS group were treated with LIPUS(40 mW/cnr.1 time/day).Cells were collected 7 d later and the RNA and total protein were extracted respectively.Real-time PCR and Western blotting were employed to analyze the expression of MMP-13 in chondrocytes at the mRNA and protein level,respectively.Results:The success rate of establishment of OA model was 83%.The results of ELISA showed that the content of TIMP-2 in the serum of animals with OA was 22.3%,lower than the one in the control group(P<0.05).Compared with the normal control group,the expression of TIMP-2in the OA model group was significantly increased,while the expression of MMP-13 was significantly increased(P<0.05).After the stimulation of LIPUS,the expression of TIMP-2 and MMP-13 was close to the one in the normal control group.Conclusions:The inner patellar ligament defect method is a mature method to establish the rabbit OA model,with high success rate.The expression of serum TIMP-2 in the OA model group is significantly decreased.LIPUS can up-regulate TIMP-2 and down-regulate MMP-13. 展开更多
关键词 Low intensity pulsed ultrasound OSTEOARTHRITIS TIM
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Osteogenic Effect of Low Intensity Pulsed Ultrasound on Rat Adipose-derived Stem Cells in vitro 被引量:5
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作者 江渟 许涛 +3 位作者 郭风劲 陈安民 肖铮铮 张迪 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2012年第1期75-81,共7页
The osteogenic in vitro effect of low intensity pulsed ultrasound (LIPUS) on SD rat adi-pose-derived stem cells (ADSCs) was investigated.Rat ADSCs underwent LIPUS (intensity=100 mW/cm2) or sham exposure for 8 min per ... The osteogenic in vitro effect of low intensity pulsed ultrasound (LIPUS) on SD rat adi-pose-derived stem cells (ADSCs) was investigated.Rat ADSCs underwent LIPUS (intensity=100 mW/cm2) or sham exposure for 8 min per treatment once everyday in vitro,and then the alkaline phos-phatase (ALP) activity and mineralized nodule formation were assessed to evaluate the osteogenic effect of LIPUS on ADSCs.To further explore the underlying mechanism,the osteogenic-related gene mRNA expression was determined by using reverse transcriptase-polymerase chain reaction (RT-PCR) at 1st,3rd,5th,7th day after exposure repectively.Westen blot was used to evaluate the protein expression levels of two osteogenic differentiation associated genes at 7th and 14th day repectively.It was found that ALP activity was increased after LIPUS exposure and LIPUS resulted in mineralized nodule formation of ADSCs in vitro.LIPUS-treated ADSCs displayed higher mRNA expression levels of runt-related transcription factor 2 (Runx2),osteocalcin (OCN),ALP and bone sialoprotein (BSP) genes than con-trols,and the protein levels of Runx2 and BSP were also increased.The results suggested that LIPUS may induce the osteogenic differentiation of ADSCs in vitro. 展开更多
关键词 low intensity pulsed ultrasound adipose-derived stem cells osteogenic differentiation
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Non-thermal ablation of rabbit liver VX2 tumor by pulsed high intensity focused ultrasound with ultrasound contrast agent:Pathological characteristics 被引量:6
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作者 Cheng-Wen Zhou Fa-Qi Li +3 位作者 Yan Qin Chun-Mei Liu Xiao-Lin Zheng Zhi-Biao Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第43期6743-6747,共5页
AIM: To investigate the pathological characteristics of non-thermal damage induced by pulsed high intensity focused ultrasound (PHIFU) combined with ultrasound contrast agent (UCA), SonoVue (Bracco SpA, Milan, I... AIM: To investigate the pathological characteristics of non-thermal damage induced by pulsed high intensity focused ultrasound (PHIFU) combined with ultrasound contrast agent (UCA), SonoVue (Bracco SpA, Milan, Italy) in rabbit liver VX2 tumor. METHODS: Liver VX2 tumor models were established in 20 rabbits, which were divided randomly into PHIFU combined with ultrasound contrast agent group (PHIFU + UCA group) and sham group. In the PHIFU + UCA group, 0.2 mL of SonoVue was injected intravenously into the tumor, followed by ultrasound exposure of Isp 5900 W/cm^2. The rabbits were sacrificed one day after ultrasound exposure. Specimens of the exposed tumor tissues were obtained and observed pathologically under light microscope and transmission electron microscope. The remaining tumor tissues were sent for 2,3,5-Triphenyltetrazolium chloride (TTC) staining. RESULTS: Before Trc staining, tumor tissues in both the sham and the PHIFU + UCA groups resembled gray fish meat, After TIC staining, the tumor tissues were uniformly stained red, with a clear boundary between tumor tissue and normal tissue, Histological examination showed signs of tumor cell injury in PHIFU + UCA group, with cytoplasmic vacuoles of various sizes, chromatin margination and karyopyknosis. Electron microscopic examination revealed tumor cell volume reduction, karyopyknosis, chromatin margination, intercellular space widening, the presence of high electro'n-density apoptotic bodies and vacuoles in cytoplasm. CONCLUSION: The non-thermal effects of PHIFU combined with UCA can be used to ablate rabbit liver VX2 tumors. 展开更多
关键词 pulsed high intensity focused ultrasound ultrasound contrast agent Non-thermal effects Rabbitliver VX2 tumors HISTOPATHOLOGY
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Effect of low-intensity pulsed ultrasound on posterolateral lumbar fusion of rabbit 被引量:1
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作者 Jian Wang Jian-Wei Li Lei Chen 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2015年第1期68-72,共5页
Objective:To observe the effect of low-intensity pulsed ultrasound in the posterolateral Lumbar fusion of rabbit.Methods:A total of 48 New Zealand white rabbits were randomly divided into the observation group and con... Objective:To observe the effect of low-intensity pulsed ultrasound in the posterolateral Lumbar fusion of rabbit.Methods:A total of 48 New Zealand white rabbits were randomly divided into the observation group and control group,including the autogenous iliac observation group.artificial bone observation group,artificial bone control group and autogenous iliac control group according to the different bone grafting.The posterolateral lumbar fusion of rabbits in each group was analyzed and compared.Results:After 4 weeks of treatment using the low-intensity pulsed ultrasound,the fusion in the bone grafting area of observation group was good.There was the relatively dense fusion area between the right transverse process and artificial bone.The left transverse process had been completely fused,with the clear bone trabecula through the fusion area.There was no significant fusion sign in the control group.According to the fusion comparison between two groups,the fusion rale of the observation group was 83.3%and it was significantly higher than the one of the control group(37.5%).Results of the comparison were statistically significant(P<0.05).The number of chondrocytes and the increase in the relative gray-scale in the fusion area of the iliac observation group were significantly higher than ones of the iliac control group(P<0.05).The number of chondrocytes and the increase in the relative gray-scale in the fusion area of the artificial bone observation group were significantly higher than ones of the artificial bone control group(P<0.05).The expression of IL-1.IL-6 and IL-17 4 weeks after the treatment of the observation group was significantly lower than the one of the control group,with the statistical significance(P<0.05).It indicated that the treatment of low-intensity pulsed ultrasound could reduce the expression level of inflammatory factors.Conclusions:The low-intensity pulsed ultrasound can significantly increase the bone grafting fusion rate of the rabbit's posterolateral lumbar fusion.The possible mechanism is that it promotes the lumbar posterolateral endochondral ossification and reduces the inflammatory reaction. 展开更多
关键词 Low-intensity pulsed ultrasound LUMBAR POSTEROLATERAL Fusion ILIUM
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Effects of low-intensity pulsed ultrasound stimulation on porous hydroxyapatite blocks for posterolateral fusion of lumbar spine in rabbits 被引量:2
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作者 卓祥龙 吕红斌 +4 位作者 徐大启 刘彬 王锡阳 张莹 胡建中 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期1921-1927,共7页
he effects of porous hydroxyapatite blocks(PHABs) and an adjunct low-intensity pulsed ultrasound stimulation(LIPUS) on the fusion rate in a rabbit spinal posterolateral fusion(PLF) model were evaluated.Twenty ra... he effects of porous hydroxyapatite blocks(PHABs) and an adjunct low-intensity pulsed ultrasound stimulation(LIPUS) on the fusion rate in a rabbit spinal posterolateral fusion(PLF) model were evaluated.Twenty rabbits underwent PLF with autograft and PHABs were randomly assigned to two groups:treated group with 20 min LIPUS daily and untreated control group for 4 weeks until euthanasia.The fused motion segments were subjected to manual palpation,gross observation,and radiographic investigation before histomorphologic and scanning electron microscopic analyses.Statistical differences between the LIPUS group and the control group are found in the fusion rate,bone density gray scale,trabecular bone formation,osteoblast-like cells,chondrocytes and positive expression of BMP-2 and TGF-β1 in the junction zone(significance level p〈0.05).The results suggest that LIPUS can increase fusion rates and accelerate bone in-growth into PHAB.Hence,PHAB and LIPUS may be used together to increase fusion rates in a rabbit spinal fusion model with a promising extension to human application. 展开更多
关键词 low-intensity pulsed ultrasound stimulation lumbar posterolateral fusion porous hydroxyapatite blocks
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Clinical efficacy of ultrasound-guided pulsed radiofrequency combined with ganglion impar block for treatment of perineal pain 被引量:2
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作者 Shui-Qing Li Ling Jiang +1 位作者 Li-Gang Cui Dong-Lin Jia 《World Journal of Clinical Cases》 SCIE 2021年第9期2153-2159,共7页
BACKGROUND Ganglion impar block alone or pulsed radiofrequency alone are effective options for treating perineal pain.However,ganglion impar block combined with pulsed radiofrequency(GIB-PRF)for treating perineal pain... BACKGROUND Ganglion impar block alone or pulsed radiofrequency alone are effective options for treating perineal pain.However,ganglion impar block combined with pulsed radiofrequency(GIB-PRF)for treating perineal pain is rare and the puncture is usually performed with X-ray or computed tomography guidance.AIM To evaluate the safety and clinical efficacy of real-time ultrasound-guided GIBPRF in treating perineal pain.METHODS Thirty patients with perineal pain were included and were treated by GIB-PRF guided by real-time ultrasound imaging between January 2015 and December 2016.Complications were recorded to observe the safety of the ultrasound-guided GIB-PRF procedure,and visual analogue scale(VAS)scores at 24 h before and after treatment and 1,3,and 6 mo later were analyzed to evaluate clinical efficacy.RESULTS Ultrasound-guided GIB-PRF was performed successfully in all patients,and no complications occurred.Compared with pretreatment scores,the VAS scores were significantly lower(P<0.05)at the four time points after treatment.The VAS scores at 1 and 3 mo were slightly lower than those at 24 h(P>0.05)and were significantly lower at 6 mo after treatment(P<0.05).There was a tendency toward lower VAS scores at 6 mo after treatment compared with those at 1 and 3 mo(P>0.05).CONCLUSION Ultrasound-guided GIB-PRF was a safe and effective way to treat perineal pain.The 6-mo short-term clinical efficacy was favorable,but the long-term outcomes need future study. 展开更多
关键词 Ganglion impar Perineal pain pulsed radiofrequency Real-time ultrasound guidance
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Effect of Low-Intensity Pulsed Ultrasound on Ischaemic Heart Disease Patients (Novel Technique)
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作者 Shaza Alturifi Mhd Firas Al Hinnawi +1 位作者 Ali Khaddam Ahmad Al Khaddour 《World Journal of Cardiovascular Surgery》 2021年第3期21-28,共8页
Ischaemic Heart Disease (IHD) or Coronary heart disease means that the heart is not getting enough blood and oxygen supply through the coronary arteries. The most common cause of this disease is the process of atheros... Ischaemic Heart Disease (IHD) or Coronary heart disease means that the heart is not getting enough blood and oxygen supply through the coronary arteries. The most common cause of this disease is the process of atherosclerosis in the coronary arteries. Although significant progress has been made in the management of ischaemic heart disease (IHD) The number of severe IHD patients is increasing. The treatment options for IHD <span lang="EN-US" style="font-family:Verdana;">have</span><span lang="EN-US" style="font-family:Verdana;"> not changed much over the last three decades</span><span lang="EN-US" style="font-family:Verdana;">,</span><span lang="EN-US" style="font-size:10pt;font-family:""> </span><span lang="EN-US" style="font-family:Verdana;">w</span><span lang="EN-US" style="font-family:Verdana;">hich </span><span lang="EN-US" style="font-family:Verdana;">is </span><span lang="EN-US" style="font-family:Verdana;">divided between medications, coronary Angioplasty and Coronary artery bypass surgery. Thus it was crucial to develop new, non-invasive therapeutic strategies in case of Failure of medical or interventional therapy or in case patient is not fit for surgery or angioplasty. In this study</span><span lang="EN-US" style="font-family:Verdana;">,</span><span lang="EN-US" style="font-family:Verdana;"> we are pleased to reveal a novel technique </span><span lang="EN-US" style="font-family:Verdana;">that</span><span lang="EN-US" style="font-family:Verdana;"> was carried out on </span><span lang="EN-US" style="font-family:Verdana;">a </span><span lang="EN-US" style="font-family:Verdana;">human model. We aimed to develop low-intensity pulsed ultrasound (LIPUS) therapy for the treatment of patients with Ischaemic Heart Disease. We have set up the inclusion and exclusion criteria, the treatment protocol of LIPUS on IHD patients. In this limited group of IHD patients, We found promising clinical results and improvement on myocardial functions.</span> 展开更多
关键词 Ischaemic Heart Disease (IHD) Low-Intensity pulsed ultrasound (LIPUS)
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The Effect of Material Surface Microstructure on the Enhancement of Bone-Bonding Ability of a Hydroxyapatite-Implant by Low-Intensity Pulsed Ultrasound (LIPUS)
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作者 Masanori Kobayashi 《Materials Sciences and Applications》 2021年第1期42-51,共10页
Excellent firm bonding between the biomaterials and bone tissue (osseointegration and osteo-conductivity) has been desired for the stability in vivo of dental implants and artificial joints. Much has been learned abou... Excellent firm bonding between the biomaterials and bone tissue (osseointegration and osteo-conductivity) has been desired for the stability in vivo of dental implants and artificial joints. Much has been learned about this concept, which has led to significant improvements in the design and surface modification of implants in the field of implant dentistry, orthopedic surgery. We have already reported that low-intensity pulsed ultrasound (LIPUS) irradiation can accelerate the bone bonding ability of the bio-conductive materials such as bioactive titanium and hydroxyapatite implant. However, it is still unclear whether the LIPUS could have same effect to different types of the bioactive-materials. Therefore, in this study, the differences of bone-like hydroxyapatite formation on some kind of hydroxyapatite surface in simulated body fluid (SBF) under the LIPUS irradiation were investigated. Two kinds of hydroxyapatite samples immersed in SBF was exposed to ultrasound waves, the bone-like apatite on the surface was analyzed by Scanning electron microscopy and X-ray diffraction. As a result, the enhancement of hydroxyapatite formation on the surface by LIPUS was confirmed, the initial epitaxial nucleation and crystal growth of apatite depended on crystal structure of the surface of matrix materials. 展开更多
关键词 Low-Intensity pulsed ultrasound (LIPUS) Simulated Body Fluid (SBF) Hydroxyapatite (HA) OSSEOINTEGRATION Osteo-Conductivity
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L-Type Calcium Channel Modulates Low-Intensity Pulsed Ultrasound-Induced Excitation in Cultured Hippocampal Neurons 被引量:2
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作者 Wen-Yong Fan Yi-Ming Chen +6 位作者 Yi-Fan Wang Yu-Qi Wang Jia-Qi Hu Wen-Xu Tang Yi Feng Qian Cheng Lei Xue 《Neuroscience Bulletin》 SCIE CAS CSCD 2024年第7期921-936,共16页
As a noninvasive technique,ultrasound stimulation is known to modulate neuronal activity both in vitro and in vivo.The latest explanation of this phenomenon is that the acoustic wave can activate the ion channels and ... As a noninvasive technique,ultrasound stimulation is known to modulate neuronal activity both in vitro and in vivo.The latest explanation of this phenomenon is that the acoustic wave can activate the ion channels and further impact the electrophysiological properties of targeted neurons.However,the underlying mechanism of low-intensity pulsed ultrasound(LIPUS)-induced neuro-modulation effects is still unclear.Here,we characterize the excitatory effects of LIPUS on spontaneous activity and the intracellular Ca^(2+)homeostasis in cultured hippocampal neurons.By whole-cell patch clamp recording,we found that 15 min of 1-MHz LIPUS boosts the frequency of both spontaneous action potentials and spontaneous excitatory synaptic currents(sEPSCs)and also increases the amplitude of sEPSCs in hippocampal neurons.This phenomenon lasts for>10 min after LIPUS exposure.Together with Ca^(2+)imaging,we clarified that LIPUS increases the[Ca^(2+)]cyto level by facilitating L-type Ca^(2+)channels(LTCCs).In addition,due to the[Ca^(2+)]cyto elevation by LIPUS exposure,the Ca^(2+)-dependent CaMKII-CREB pathway can be activated within 30 min to further regulate the gene transcription and protein expression.Our work suggests that LIPUS regulates neuronal activity in a Ca^(2+)-dependent manner via LTCCs.This may also explain the multi-activation effects of LIPUS beyond neurons.LIPUS stimulation potentiates spontaneous neuronal activity by increasing Ca^(2+)influx. 展开更多
关键词 Low-intensity pulsed ultrasound NEUROMODULATION L-type calcium channel Hippocampal neuron
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Pulse wave Doppler ultrasound of testicular arteries and their relationship with semen characteristics in healthy bulls 被引量:1
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作者 Alessia Gloria Augusto Carluccio +3 位作者 Laura Wegher Domenico Robbe Claudio Valorz Alberto Contri 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第2期319-325,共7页
Background: Semen evaluation is used to estimate the testicular function. In bulls, the spermatozoa present in the ejaculate are the result of a process that begun more than 2 mo earlier, bequeathing a delayed depicti... Background: Semen evaluation is used to estimate the testicular function. In bulls, the spermatozoa present in the ejaculate are the result of a process that begun more than 2 mo earlier, bequeathing a delayed depiction of the actual function of the testis. Since testis vascularization might be critical for the gonad function, selected pulse wave Doppler ultrasound parameters were assessed in this study, for instance the peak systolic velocity, the end diastolic velocity and the resistive index of the testicular artery along the spermatic cord, the marginal portion of the testicular artery and the intratesticular branches of the testicular artery both in healthy adult and young bulls.Correlations between these parameters and characteristics of semen that was collected numerous times, before and after the Doppler ultrasound examination.Results: The peak systolic velocity and the end diastolic velocity measured in the testicular artery along the spermatic cord(supratesticular artery – SA) were variable among the bulls and within individual bulls, likely due to the convoluted course of the vessel. The resistive index was found highly repeatable in the same bull. A reduction in the resistive index was found between the supratesticular artery and the marginal portion of the testicular artery(P < 0.01), and between the marginal portion of the testicular artery and the intratesticular branches of the testicular artery(P < 0.05). No differences were recorded for the pulse wave Doppler ultrasound parameters in young bulls compared with adults. A significant correlation was found between the resistive index of the marginal portion of the testicular artery and total sperm in the ejaculate(r = 0.516, P < 0.05), the immature sperm(r = 0.462, P < 0.05), the teratoid sperm(r = 0.375, P < 0.05), and the "Dag defect" sperm(r = 0.389, P < 0.05). Similarly, the resistive index of the intratesticular branches of the testicular artery were found correlated with the total sperm number in the ejaculate(r = 0.568, P < 0.05), the immature sperm(r = 0.523, P < 0.05), the teratoid sperm(r = 0.418, P < 0.05), and the "Dag defect" sperm(r = 0.341, P < 0.05).Conclusions: The data presented in this study suggest that the resistive index, measured at the marginal portion of the testicular artery, could be an easy-to-perform parameter to evaluate the spermatogenesis quality in young bulls and normal adults. 展开更多
关键词 BULL pulse wave Doppler SPERM morphology TESTIS ultrasound
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Contrast enhancement of medical ultrasound imaging with reversal phase-inversion pulse technology 被引量:1
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作者 李琴 谭冠政 A.S.M.Libda 《Journal of Central South University》 SCIE EI CAS 2013年第3期696-701,共6页
A new ultrasound contrast imaging technique was proposed for eliminating the harmonic components from the emission signal transmitted by the broadband ultrasonic system.Reversal phase-inversion pulse was used for the ... A new ultrasound contrast imaging technique was proposed for eliminating the harmonic components from the emission signal transmitted by the broadband ultrasonic system.Reversal phase-inversion pulse was used for the first time to separate the contrast harmonics from the harmonics in the emission signal to improve the detection of contrast micro-bubbles.Based on the nonlinear acoustic theory of finite-amplitude effects and the associated distortion of the propagating wave,the Bessel-Fubini series model was applied to describe the nonlinear propagation effects of the reversal phase-inversion pulse,and the Church's equation for zero-thickness encapsulation model was used to produce the scattering-pulse of the bubble.For harmonic imaging,the experiment was performed using a 64-element linear array,which was simulated by Field II.The results show that the harmonic components from the emission signal can be completely cancelled,and the harmonics generated by the nonlinear propagation of the wave through the tissue,can be reduced by 15-30 dB.Compared with the short pulse,the reversal phase-inversion pulse can improve the contrast and definition of the harmonic image significantly. 展开更多
关键词 reversal pulse phase inversion Church model ultrasound imaging CONTRAST
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An Adaptive Pulse Compression Filter for Ultrasound Contrast Harmonic Imaging
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作者 Jenho Tsao Ming-Huang Chen 《Engineering(科研)》 2013年第10期118-122,共5页
Coded excitation is useful for ultrasound contrast imaging to increase penetration and SNR, and improve the contrast to tissue ratio (CTR). The waveform of bubble response depends greatly on bubble size, the frequency... Coded excitation is useful for ultrasound contrast imaging to increase penetration and SNR, and improve the contrast to tissue ratio (CTR). The waveform of bubble response depends greatly on bubble size, the frequency and bandwidth of the excitation chirp signal. This makes the pulse compression filter based on square-law be wrong for bubbles with changing sizes. In this paper, an adaptive pulse compression (APC) filter for the second harmonic of microbubble with varying size distribution is proposed. The APC filter is designed based on the estimated power spectrum of the received bubble harmonic echoes. Theoretical analysis and simulation studies are presented for evaluating performance of the APC filter. For monodisperse bubble, the power improvement factor of the APC filter can be more than 20 dB. 展开更多
关键词 ultrasound CONTRAST Imaging SQUARE LAW pulsE Compression Adaptive pulsE Compression
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基于多频脉冲采样的血流速度估计方法
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作者 马碧云 范逸华 刘娇蛟 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第10期22-30,共9页
传统双模超声技术相较于新兴技术更具实现可穿戴化的潜力。在进行脉冲多普勒血流速度估计时,双模超声需同时发射B模式脉冲进行成像定位,这要求B模式脉冲和多普勒脉冲共享采样时间。采用基于单频多普勒脉冲的稀疏间隔发射方式可以解决这... 传统双模超声技术相较于新兴技术更具实现可穿戴化的潜力。在进行脉冲多普勒血流速度估计时,双模超声需同时发射B模式脉冲进行成像定位,这要求B模式脉冲和多普勒脉冲共享采样时间。采用基于单频多普勒脉冲的稀疏间隔发射方式可以解决这一问题,但常见的稀疏发射排布方式(如嵌套发射、互质发射等)存在采样时间窗较长的缺点,特别是在血流速度变化明显的情况下存在时间分辨率不足的问题。此外,长时间窗包含了较多的血流速度分量,容易由于稀疏采样引起伪影,从而影响血流速度估计的准确性。因此,文中提出了一种基于多频脉冲采样的新型血流速度估计方法。首先,构建了多频脉冲采样的回波模型,并对该模型进行推导,证明了在频率衰减平稳假设下,该数学模型等价于单频多普勒脉冲稀疏发射方式,即多频脉冲采样可以通过较短的时间窗实现类似于基于单频脉冲采样模式的长时间窗的性能,从而提高血流速度谱的时间分辨率和估计精度;然后,提出了两种可用于多频脉冲采样模式的血流速度谱的构建方法,分别为复杂度较低的BMUSIC算法和伪影抑制效果较佳的VMUSIC算法。基于FieldⅡ仿真数据和人体实测数据的实验结果表明:相较于单频多普勒脉冲稀疏发射方式,文中方法不仅可以采用较短的时间窗提升血流速度谱的时间分辨率,还可以获得连续、清晰、精度较高且伪影抑制效果较佳的血流速度估计结果;在人体实测数据实验中,由于实验条件所限,文中方法无法实现非整数倍频,未能充分展现VMUSIC算法的性能优势。 展开更多
关键词 血流速度估计 多普勒超声信号 多频脉冲
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低强度脉冲超声波对髁突软骨细胞炎症状态的作用研究
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作者 李静 丁思琪 +1 位作者 蓝鹏 李琼 《内蒙古医科大学学报》 2024年第1期1-5,10,共6页
目的 观察低强度脉冲超声波对白介素-1β制造的大鼠髁突软骨细胞炎症模型中MAPK信号通路相关因子磷酸化的表达变化。方法 二次酶消化法分离髁突软骨细胞并完成鉴定。将分离出的大鼠髁突软骨细胞随机分为3组,加入3种不同浓度的IL-1β处... 目的 观察低强度脉冲超声波对白介素-1β制造的大鼠髁突软骨细胞炎症模型中MAPK信号通路相关因子磷酸化的表达变化。方法 二次酶消化法分离髁突软骨细胞并完成鉴定。将分离出的大鼠髁突软骨细胞随机分为3组,加入3种不同浓度的IL-1β处理并进行Ⅱ型胶原与MMP-13免疫细胞化学染色,筛选出最佳致炎浓度。再次将所提取的大鼠髁突软骨细胞随机分为3组:NC组、OA组、LIPUS组,处理后对Ⅱ型胶原、p38、p-p38、ERK1/2、pERK1/2进行免疫细胞化学染色,观察蛋白表达情况。结果(1)成功提取大鼠髁突软骨细胞。(2)IL-1β:10 ng/mL组Ⅱ型胶原表达量降低最明显,差异有统计学意义(P<0.05),MMP-13表达量升高最明显,差异有统计学意义(P<0.05)。(3)OA组与LIPUS组Ⅱ型胶原表达量均降低,差异有统计学意义(P<0.05),OA组降低更明显,差异有统计学意义(P<0.05)。3组的p38、ERK1/2表达量无明显差异(P>0.05)。OA组与LIPUS组p-p38、p-ERK1/2表达量均升高,差异有统计学意义(P<0.05),OA组升高更明显,差异有统计学意义(P<0.05)。结论(1)二次酶消化法成功提取大鼠髁突软骨细胞。(2)10 ng/mL为IL-1β最佳致炎浓度。(3)LIPUS处理可减少炎性髁突软骨细胞中Ⅱ型胶原的降解,抑制了MAPK通路相关因子p38、ERK1/2的磷酸化。 展开更多
关键词 颞下颌关节骨关节炎 低强度脉冲超声波 髁突软骨细胞 免疫细胞化学染色 MAPK通路
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一种用于尿道瘢痕防治动物实验的超声探头设计
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作者 刘畅 王欣钰 +2 位作者 郑其斌 王春辉 郑政 《北京生物医学工程》 2024年第4期370-376,共7页
目的 尿道瘢痕是患者尿道手术后常见的并发症之一,并且难以通过手术治疗方法清除。低强度脉冲超声(low intensity pulse ultrasound,LIPUS)在抑制纤维化,抑制炎症方面有十分突出的表现,为超声防治尿道瘢痕提供了理论的可能性。尽管如此... 目的 尿道瘢痕是患者尿道手术后常见的并发症之一,并且难以通过手术治疗方法清除。低强度脉冲超声(low intensity pulse ultrasound,LIPUS)在抑制纤维化,抑制炎症方面有十分突出的表现,为超声防治尿道瘢痕提供了理论的可能性。尽管如此,目前并没有对超声用于尿道瘢痕的防治作用的报道,另外有关超声抑制纤维化、抑制炎症的作用机制也仍需要进一步的研究。本文针对新西兰雄兔尿道重建模型设计了一种超声探头,用于LIPUS抑制尿道瘢痕疗效和作用机制的动物实验研究。方法 根据兔阴茎的尺寸与形状设计探头结构,通过有限元仿真预测探头声场,用3D打印技术制造原型机。最后对探头声场进行测试,并且用于动物实验验证其实用性。结果 探头超声频率为2 MHz,治疗腔长度44 mm,直径8 mm。治疗腔沿长度方向上有3个紧邻的治疗区,每个治疗区的半功率长度约6 mm,治疗区内的I_(sata)(时间平均空间平均声强)可通过前端驱动器电源电压进行调节,当电源电压为30 V时,I_(sata)大于0.87 W/cm^(2)。结论 本文设计的超声探头体积小、重量轻、声场均匀,可以对动物尿道实施稳定有效的超声照射,为超声治疗尿道瘢痕动物实验提供了一种有用的工具。 展开更多
关键词 低强度脉冲超声 尿道瘢痕 超声探头 超声治疗 有限元仿真
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低强度体外冲击波/脉冲式超声波治疗勃起功能障碍中国专家共识 被引量:2
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作者 中国性学会能量医学与男科装备分会《低强度体外冲击波/脉冲式超声波治疗勃起功能障碍中国专家共识》编写组 张祥生 +3 位作者 姜涛 卢慕峻 李彦锋 陈鑫 《中国性科学》 2024年第1期1-8,共8页
勃起功能障碍(ED)是成年男性的常见病和多发病,目前国内外ED诊疗指南推荐的口服药物、阴茎海绵体内血管活性药物注射和阴茎假体植入等治疗方案均不能针对ED病因,故无法从纠正发病机制方面彻底治愈ED。低强度体外冲击波疗法(Li-ESWT)和... 勃起功能障碍(ED)是成年男性的常见病和多发病,目前国内外ED诊疗指南推荐的口服药物、阴茎海绵体内血管活性药物注射和阴茎假体植入等治疗方案均不能针对ED病因,故无法从纠正发病机制方面彻底治愈ED。低强度体外冲击波疗法(Li-ESWT)和低强度脉冲式超声波(LIPUS)治疗ED,因其独特的作用机制和生物学效应,不仅能够改善患者的勃起功能,亦能针对病因治疗,促进阴茎功能康复。然而,目前临床上存在Li-ESWT和LIPUS治疗ED适应证不明确、治疗方案不统一、疗效差异大等问题,限制了该类疗法的进一步应用。据此,中国性学会组织本领域内多位临床专家,根据现有的Li-ESWT和LIPUS治疗ED的国内外循证医学证据,经共同研究、讨论达成一致,制定了本共识,旨在为从事Li-ESWT及LIPUS治疗ED领域的临床医生、设备研发人员提供规范的治疗方法和参考。 展开更多
关键词 勃起功能障碍 低强度体外冲击波 低强度脉冲式超声波 治疗效果 适应证
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高电压长时程脉冲射频术与低温等离子消融术治疗颈源性头痛的疗效比较 被引量:2
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作者 赵晓静 梁惠 +1 位作者 郭玉娜 武百山 《实用医学杂志》 CAS 北大核心 2024年第1期85-90,共6页
目的比较低温等离子消融术与高电压长时程脉冲射频术治疗颈源性头痛(cervicogenic headache,CEH)的疗效和安全性。方法收集颈源性头痛患者80例,按照手术方式分为两组:低温等离子消融组(L组,n=50);高电压长时程脉冲射频组(H组,n=30)。L... 目的比较低温等离子消融术与高电压长时程脉冲射频术治疗颈源性头痛(cervicogenic headache,CEH)的疗效和安全性。方法收集颈源性头痛患者80例,按照手术方式分为两组:低温等离子消融组(L组,n=50);高电压长时程脉冲射频组(H组,n=30)。L组采用颈脊神经后内侧支低温等离子消融术联合肌筋膜松解,H组采用颈脊神经后内侧支高电压长时程脉冲射频术联合肌筋膜松解。记录患者术前(T_(0))及术后1周(T_(1))、4周(T2)、12周(T_(3))、24周(T_(4))的视觉模拟评分(VAS评分)、颈部活动障碍评分(ROM评分)、术后疼痛缓解率以及术后并发症的发生率,比较两组之间的有效性和安全性。结果两组患者术后各时点的VAS评分、ROM评分均较T_(0)下降,差异有统计学意义(P<0.05);与L组相比,H组各时点的VAS评分均降低,差异有统计学意义(P<0.05),H组各时点的ROM评分均降低,差异无统计学意义(P>0.05),T_(4)时点H组的有效率高于L组,差异有统计学意义(P<0.05)。两组术后均有头皮麻木的情况,T_(3)时点H组的麻木发生率稍高于L组,差异有统计学意义(P<0.05)。结论低温等离子消融术和高电压长时程脉冲射频术治疗颈源性头痛均有效,安全性均较好,但高电压长时程脉冲射频术术后24周的疗效优于低温等离子消融术。 展开更多
关键词 颈源性头痛 低温等离子消融术 高电压长时程脉冲射频术 超声引导
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滚动轴承润滑膜厚及保持架转速的超声测量 被引量:1
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作者 薛梓涵 赵自强 +1 位作者 葛翔宇 王文中 《轴承》 北大核心 2024年第2期46-54,共9页
滚动轴承的运行稳定性与钢球和内外圈之间的润滑状态密切相关,膜厚则是表征轴承润滑性能的重要参数。基于超声弹簧模型建立了膜厚测量模型并搭建了试验台,通过试验台模拟球轴承的运行状态并测量钢球周围以及沿滚动方向的膜厚分布,分析... 滚动轴承的运行稳定性与钢球和内外圈之间的润滑状态密切相关,膜厚则是表征轴承润滑性能的重要参数。基于超声弹簧模型建立了膜厚测量模型并搭建了试验台,通过试验台模拟球轴承的运行状态并测量钢球周围以及沿滚动方向的膜厚分布,分析了转速对最小膜厚的影响;同时,根据连续2个钢球通过探头正下方的时间间隔计算保持架转速,分析得到了不同重复频率所能测量的保持架转速范围。试验结果表明,膜厚的实际测量值与理论值吻合较好,保持架转速的实际测量值与纯滚动条件下的理论转速一致性良好,可用于轴承打滑状态的评估。 展开更多
关键词 滚动轴承 润滑 超声 最小油膜厚度 保持架 转速 脉冲重复频率
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脉冲超声对灰枣片理化及超声液特性的影响
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作者 王凤昭 吕明月 +2 位作者 吕健 陈芹芹 毕金峰 《中国食品学报》 EI CAS CSCD 北大核心 2024年第7期297-307,共11页
为探究脉冲超声持续时间对枣片理化及超声液特性的影响,以灰枣为原料,设置脉冲超声持续时间为15,30,60 s,并分别于1,2,3,4,5 h对灰枣片和超声液进行取样分析。追踪检测灰枣片的色泽、水分状态、质构和微观结构,以及超声液可溶性固形物(T... 为探究脉冲超声持续时间对枣片理化及超声液特性的影响,以灰枣为原料,设置脉冲超声持续时间为15,30,60 s,并分别于1,2,3,4,5 h对灰枣片和超声液进行取样分析。追踪检测灰枣片的色泽、水分状态、质构和微观结构,以及超声液可溶性固形物(TSS)、色泽、浊度和电导率的变化。结果表明,随着脉冲超声处理时间的延长,灰枣片中的主要水分由结合水转变为自由水,灰枣片组织吸水膨胀,色泽L*值(42.88~50.71)和△E值(3.69~9.85)呈显著增加的趋势,a*值(由19.88降至14.70)和b*值(由22.39降至19.03)呈显著降低的趋势。脉冲超声处理可诱导灰枣片组织内微通道的形成,随着循环次数的增加和脉冲时间的延长,微通道发生扩张,数量增加,同时伴随咀嚼性、弹性和回复性降低。超声液分析结果表明,高强度脉冲持续时间(30 s和60 s)可使灰枣片与超声液在处理前期(1~2 h)发生快速传质,超声液色泽(△E值:0~26.69)、TSS(0~6.1°Brix)、电导率(0~257.54μs/cm)、浊度(0~8.81 NTU)等显著增加,处理后期(3~5 h),15 s处理组超声液特性呈现出最显著的特性变化;至处理完成,各处理组超声液色泽L*值均达到100,a*值与b*值接近于原始状态;同时30 s和60 s处理组超声液中TSS为0°Brix,传质趋于平衡。结论:可根据灰枣片和超声液特性的改变来判断传质的程度,从而适应不同的加工需求。 展开更多
关键词 脉冲超声 灰枣 超声液 持续时间 可溶性固形物
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