• 제목/요약/키워드: Ultrasound Intensity

검색결과 222건 처리시간 0.022초

초음파가 생쥐의 혈소판에 미치는 영향 (The effects of Ultrasound on the Platelet of Rats)

  • 조광호;박상옥;박래준
    • The Journal of Korean Physical Therapy
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    • 제13권1호
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    • pp.139-149
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    • 2001
  • We found out that there exists threshold dose for the decreased platelet count when we apply change of the platelet count to the defense of the ultrasound experiment. Those diminution is definite effects from the defense of the ultrasound. The number of the platelet count is decreased when we are exposed to ultrasound simultaneously. This should not be occurred. It is easy to use the number of the platelet count in the measurement of the biological dosage and intensity in high dosage relatively due to definite quantative relationship. The biological index to understand synergic effects. which are present when two harmful environmental factors are operating at the same time is functionally assending and antagonistic. There are scattered many factors as physical, Chemical, or physiochemically elements which are harmful to human body in the environment in consideration of ultrasound and the other factors. This experiment is demonstrating that we can use the change of the platelet as an index representing synergic effects of ultrasound.

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흰쥐 슬관절 고정 후 초음파 적용이 관절연골내 HSP70의 발현에 미치는 영향 (The Effects of Ultrasound Irradiation on the Heat Shock Protein 70(HSP70) Expression in Rat Knee Articular Cartilage after Immobilization)

  • 남기원
    • The Journal of Korean Physical Therapy
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    • 제17권3호
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    • pp.369-376
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    • 2005
  • The purpose of the study was for investigating the effect of therapeutic ultrasound irradiation on HSP70 expression in knee of degraded rat articular cartilage. Knee of ten Sprague-Dawley male rats were immobilized for 4 weeks and divided at random into the control and continuous ultrasound applicated group. The continuous ultrasound applicated group was irradiated with frequency 1MHz, intensity $1W/cm^2$ for 5 minutes. The control group was sham sonication. The immunoreactivity of HSP70 was increased in degraded articular cartilage after untrasound irradiation. These results suggest that therapeutic ultrasound can enhance HSP70 expression in degraded articular cartilage.

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Comparative Study of Contrast-Enhanced Ultrasound Qualitative and Quantitative Analysis for Identifying Benign and Malignant Breast Tumor Lumps

  • Liu, Jian;Gao, Yun-Hua;Li, Ding-Dong;Gao, Yan-Chun;Hou, Ling-Mi;Xie, Ting
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권19호
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    • pp.8149-8153
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    • 2014
  • Background: To compare the value of contrast-enhanced ultrasound (CEUS) qualitative and quantitative analysis in the identification of breast tumor lumps. Materials and Methods: Qualitative and quantitative indicators of CEUS for 73 cases of breast tumor lumps were retrospectively analyzed by univariate and multivariate approaches. Logistic regression was applied and ROC curves were drawn for evaluation and comparison. Results: The CEUS qualitative indicator-generated regression equation contained three indicators, namely enhanced homogeneity, diameter line expansion and peak intensity grading, which demonstrated prediction accuracy for benign and malignant breast tumor lumps of 91.8%; the quantitative indicator-generated regression equation only contained one indicator, namely the relative peak intensity, and its prediction accuracy was 61.5%. The corresponding areas under the ROC curve for qualitative and quantitative analyses were 91.3% and 75.7%, respectively, which exhibited a statistically significant difference by the Z test (P<0.05). Conclusions: The ability of CEUS qualitative analysis to identify breast tumor lumps is better than with quantitative analysis.

Weak Shock Theory를 이용한 초음파의 비선형 전파에 의한 온도 상승 (Temperature Rise due to Nonlinear Propagation of Ultrasound using Weak Shock Theory)

  • 최민주;성굉모;이상은;정병하;이무상
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.74-75
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    • 1998
  • The present study employs weak shock theory and bio-heat transfer function to predict the temperature rise due to nonlinear propagation of high amplitude ultrasound. The theory shows that, for the focused ultrasound which is assumed to have an gaussian beam profile and has the focal intensity of $1000W/cm^2$, the temperature rise of liver tissue exposed for 1 second to the energy lost during nonlinear propagation goes up to about $30^{\circ}C$. This indicate that it is necessary to consider the nonlinear propagation induced heating enhancement when setting exposure condition of high intensity focused ultrasound used for cancer thermotherapy.

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우슬과 초음파가 퇴행성관절염 백서의 관절 연골에 미치는 영향 (Effect of Achyrantis Radixs and Ultrasound in Osteoarthritis Rats Articular Cartilage)

  • 김은정;정현우;김계엽
    • 동의생리병리학회지
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    • 제22권2호
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    • pp.390-396
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    • 2008
  • Osteoarthritis(OA) diseases are characterized by joint pain, tenderness, limitation of movement, crepitus, occasional effusion, and variable degrees of inflammation without systemic effects. We investigated the effects of Achyrantis radixs cream treatment and low intensity ultrasound in monosodium iodoacetate(MIA) induced experimental osteoarthritis rat. Sprague-Dawley 40 rats of 7-8 weeks, weight $250\;{\pm}\;50$ g were divided into four groups including the control group and ostoarthritis group(30 rats). Histopathological examination, Mankin's score, and immunohistochemical were performed. Histological findings in control group that are similar to those observed in human osteoarthritis, such as disorganization of chondrocytes, erosion and fibrillation of cartilage surface, and subchondral bone exposure. Safranin O-fast green staining revealed that marked diffuse reduction of proteoglycans and chondrocyte treated with MIA. The Mankin's score were closely correlated to the grade of histological findings. The level of Bax and caspase-3 expression decreased experimental groups. This study shows that a Acyranthes Radix cream treatment and low intensity ultrasound exerts a beneficial influence on the severity of chondral lesion in osteoarthritis rats. This treatments could related to a reduced level of chondrocyte apoptosis through anti-apoptotoc capacities of MIA-induced apoptotic protein overexpression.

The effects of therapeutic ultrasound stimulation on the inflammation cytokine in rat articular chondrocytes

  • Kim, Eun-Jung;Hwang, Sujin;Kim, Gye-Yeop
    • Physical Therapy Rehabilitation Science
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    • 제2권1호
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    • pp.21-26
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    • 2013
  • Objective: The aim of this study was to investigate the effect of therapeutic ultrasound (US) of cell viability and inflammatory cytokine in rat articular chondrocyte cultures stimulated with lipopolysaccharide (LPS). Design: One group pretest-posttest design. Methods: Cultured chondrocytes were treated with US and/or LPS and assessed for viability, Tumor necrosis factor $(TNF)-{\alpha}$ and Interleukin (IL)-1 production. Results: Oxidative stress was induced in rat chondrocytes with LPS. The cell viability was decreased in chondrocytes after treatment with LPS. The viability revealed that low-intensity pulsed ultrasound (LIPUS) exerted no significant cytotoxicity in the rat chondrocyte. LIPUS inhibited decreased cell viability in the presence of LPS ($30{\mu}g/ml$) in a intensity dependent pattern at LIPUS (p<0.05). $TNF-{\alpha}$ production in the presence of LPS was also inhibited in a dose dependent manner (p<0.05 from $30mW/cm^2$). IL-1 production in the presence of LPS was inhibited as well (p<0.05 from $7.5mW/cm^2$). Conclusions: Our results demonstrate that US was the anti-inflammatory effect of chondrocytes. LIPUS may exert its anti inflammatory effects through inhibition of $TNF-{\alpha}$ and IL-1 synthesis. These results suggest that US have potential for use as a pain relief and reduce the articular destruction.

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고강도 집속형 초음파의 주파수 성분 특성에 따른 공동 현상 억제 효과 (Cavitation Suppression Effects by the Modification of the Spectral Characteristics of High Intensity Focused Ultrasound)

  • 최민주
    • 한국음향학회지
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    • 제18권5호
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    • pp.68-77
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    • 1999
  • 본 논문에서는 고강도 집속형 초음파의 주파수 특성(파형)에 따른 초음파 공동 현상을 억 제하는 효과를 살펴보았다. 본 연구에서는 세가지 파형, 즉, 정현파(1 MHz, 5 MPa), 주파수 변조파(10 ㎲ 동안 1 MHz에서 6 MHz까지 선형적으로 증가, 5 MPa), 비대칭 충격파(기 본 주파수 1 MHz, 양압 12 MPa, 음압 -4 MPa)를 고려하였다. 동일한 강도(833 W/㎠)를 가지는 각 초음파에 노출된 초기 반경이 1 ㎛인 물 속에 있는 공기 기포의 반응을Gilmore bubble dynamic model 및 Church's rectified gas diffusion equation을 이용하여 예측하였다. 기포 진동의 크기는, 정현파에 노출된 경우와 비교하여, 주파수 변조된 초음파의 경우 현저히 감소하였고, 비대칭 충격파의 경우 약간 감소함을 볼 수 있었다. 흥미롭게도 주파수 변조파에 대한 기포의 반응은 변조된 초음파의 주파수 성분이 기포의 공진 주파수(3 MHz) 이상에서는 거의 동일하게 유지되는 것으로 나타났다. 이 사실은 주파수 변조를 현재의 1 MHz부터 6 MHz까지에서 1 MHz부터 3 MHz까지로 줄여도 유사한 공동 억제 효과를 얻을 수 있음을 암시한다. 실용적으로, 비교적 좁은 밴드 폭을 가지는 범용 초음파 변환기를 이 용하여 초음파의 공동 현상 억제 효과를 얻기 위한 주파수 변조를 구현할 수 있음을 의미한다. 본 연구의 결과는 초음파의 적절한 주파수 성분 조절로 초음파의 공동 현상을 일정 수준 억제할 수 있음을 시사한다.

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저강도 맥동성 초음파 적용이 관절연골세포에 미치는 영향 (Effect of Low Intensity Pulsed Ultrasound in Rat Chondrocyte)

  • 김은정;김계엽
    • 동의생리병리학회지
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    • 제22권5호
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    • pp.1262-1269
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    • 2008
  • Low intensity pulsed ultrasound(LIPUS) is known to accelerate bone regeneration, but the precise cellular signaling mechanism is still unclear. The purpose if this study was to determine the effect of LIPUS on the signaling mechanism of rat chondrocyte. In the explant culture condition, there was inhibition effect of 1 $W/cm^2$ intensity LIPUS on chondrocytes proliferation but chondrocytes proliferation was increased at 0.25 $W/cm^2$ intensity. In addition, western blot analysis of MAPKs showed that LIPUS increased ERK1/2 activity from the 10 min treatment of LIPUS. Hydrogen peroxide($H_2O_2$), resulted in a time- and dose-dependent cell proliferation, which was largely attributed to apoptosis. $H_2O_2$ treatment caused marked sustained nucleus condensation in Hoechst stain. LIPUS and $H_2O_2$ activates phosphorylation of p-ERK1/2 and PD 98059($10^{-5}M$) blocked the effect of LIPUS and $H_2O_2$. Moreover, the synergistic phosphorylation of p44/42 MAPK by $H_2O_2$, LIPUS was selectively inhibited by PD 98059, ERK1/2 inhibitor. In order to determine whether the increase in cell proliferation caused by $H_2O_2$ and LIPUS could be explained by changes in the level of the prostaglandin $E_2$. Our study demonstrated that LIPUS stimulate the cell proliferation via activated phosphorylation of ERK1/2 in condrocyte. LIPUS has anabolic effects on rat cartilage in explant cultures, indicating a potential important method for the treatment of osteoarthritic cartilarge.

Adjuvant로 유발된 관절염의 흰 쥐에서 초음파의 임상반응 (Clinical Responses of Ultrasound on Adjuvant-Induced Arthritis in Rats)

  • 이동진
    • 한국전문물리치료학회지
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    • 제10권2호
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    • pp.45-59
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    • 2003
  • The purpose of this study was to assess the effects of ultrasound on adjuvant-induced arthritis in rats. Adjuvant arthritis was induced in 26 female Sprauge-Dawley rats by the subcutaneous injection of a single dose of .1 mL of Complete Freund's Adjuvant (CFA) (1 mg of Mycobacterium Butyricum suspended in .1 $m{\ell}$ paraffin oil) into the right hind paw. After confirming inflammatory edema and arthritis in the paw 2 weeks later, the arthritic rats were divided into 3 groups, i.e., a control group, a pulsed ultrasound group (Group A), and a continuous ultrasound group (Group B) with 8 rats placed in each group. The rats in Group A were treated with pulsed ultrasound at 1 MHz frequency with .5 $W/cm^2$ intensity in 1 : 4 mode for 3 minutes. The rats in Group B were treated with continuous ultrasound at 1 MHz frequency with 2 $W/cm^2$ intensity in the continuous mode for 3 minutes. The ultrasound treatment was done in the left and right ankles for 2 weeks. Clinical, radiographic and histopathologic findings were then evaluated before and after treatment and yielded the following results. 1. No significant difference was present in body weight between the control group and the treated groups. 2. A statistically significant decrease in the edema of the paw was seen in the rats in Group A that was treated with pulsed ultrasound by 26~29 days after the treatment started (p<.05). 3. According to radiological examination, Group A showed the lowest score in arthritis scale which means it showed a tendency to suppress arthritic inflammation of the left and right hind paws. However, no statistically significant difference was present in the score between the control group, Group A and Group B. 4. According to histopathologic findings, the degree of infiltration by inflammatory cells and hypertrophy of the synovium were less in Group A compared with the control group and Group B. The results of the study show that rats that were treated with the pulsed ultrasound effectively suppressed adjuvant arthritis. However, more effort is needed to objectively prove the effectiveness of ultrasound by developing more sensitive testing methods that could quantitatively evaluate the treatment effects of acute rheumatoid arthritis and by trying out different ultrasound treatment methods.

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초음파 방사힘을 이용한 손바닥의 촉각 인식과 응용 (Haptic recognition of the palm using ultrasound radiation force and its application)

  • 김선애;김태양;이열음;이수연;정목근;권성재
    • 한국음향학회지
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    • 제38권4호
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    • pp.467-475
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    • 2019
  • 고출력의 초음파는 매질을 진행하면 음향 흐름과 음향 방사힘을 만들어낸다. 공기를 매질로 하는 3차원 공간상에 음향 방사힘을 발생시키면 입체적인 촉감을 형성할 수 있으므로 공간적인 정보를 직접 피부에 촉각으로 전달할 수 있다. 본 논문은 40 kHz의 작은 초음파 송신자 154개를 묶어 오목한 형태로 배열시켜서 초음파를 송신하여 집속초점에서 음향 방사힘을 발생시켰다. 초음파 음장의 초점의 근처에서 음향 방사힘에 의한 촉각을 확인하였다. 촉각 감도를 올리기 위하여 송신 초음파를 60 Hz의 구형파로 진폭 변조를 하였다. 초음파 촉각의 응용으로 음향 방사힘이 형성되는 허공에 촉각이 감지되는 영역을 형성시켜서, 손의 위치를 지정하는 지시자로 사용하였다. 촉각이 감지되는 초점위치에 있는 손의 모양을 영상 입력으로 받아서 손가락의 개수를 기계에 피드백하는 시스템을 구현함으로써 초음파를 이용한 촉각의 유용성을 확인하였다.