• 한국수산과학회지
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• 제32권5호
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• pp.607-611
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• 1999

초음파를 이용하여 저분자 $\lambda$-carrageenan을 제조한 다음 그 특성을 조사한 결과 가용한계농도에 있어서는 대조구 $\lambda$-carrageenan는 $3\%$에서 가용한계농도를 나타내었고, 초음파 처리에 의해 저분자화가 많이 될수록 가용한계농도는 더 높게 나타났다. 알콜 침전도는 대조구에 비해 초음파 처리구가 낮게 나타났다. 유화능은 대조구에 비하여 처리구가 낮게 나타났으며, 분자량이 낮을 수록 유화능은 낮게 나타났다. 점도는 예상하였던 대로 초음파 처리에 의해 저분자화된 $\lambda$-carrageenan (P-1, P-2)이 대조구에 비해 낮았으며, 초음파 처리가 많이 될수록 점도는 낮게 나타났다. $\lambda$-carrageenan이 갈변반응에 대하여 크지는 않으나 어느 정도 갈변억제효과를 가지고 있는 것으로 나타났으며, 저분자화가 많이 될수록 갈변억제효과는 전반적으로 떨어지는 것으로 나타났다. 전기영동을 이용하여 $\lambda$-carrageenan 및 저분자화된 $\lambda$-carrageenan의 분자량을 조사한 결과 대조구 $\lambda$-carrageenan의 분자량은 약 250,000이었으며 초음파 처리에 따른 저분자화 된 $\lambda$-cariageenan의 분자량은 각각 184,000(P-1) 및 67,000 (P-2)정도 이었으며, GPC 결과도 이와 비슷하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권3호
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• pp.163-172
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• 2012

Purpose: Diabetes mellitus (DM) has been shown to alter the properties of the bone and impair bone healing around a titanium implant. The aim of this study is to investigate whether the low-intensity pulsed ultrasound (LIPUS), which has been known to stimulate the bone healing, improve the osseointegration of the titanium implant in tibia of DM-induced rats. Methods: 16 rats were received streptozotocin (60 mg/kg) for inducing diabetes. A total number of 32 titanium implants were placed bilaterally into both tibiae of these rats. The right tibia of each rat received LIPUS application (10 min/day) during 7 days post-operation, while the left side received no treatment. The study was carried on for six weeks and the rats were sacrificed at 1, 2, 4, and 6 weaks postoperatively (4 rats for each week) for histomorphometric and histologic analysis. Bone-implant contact and bone area were measured. Comparisons between the groups were made using statistical analysis on histomorphometric analysis. Results: The histomorphometry parameters showed that the bone-implant contact and the bone area values have decreased in the late osseointegration periods (4, 6 weeks) compared to the early osseointegration periods (1, 2 weeks) in both two groups. The bone-implant contact values of the LIPUS group were somewhat higher than those of controls at 1, 2 weeks, but the difference was not statistically significant. The bone area values of the LIPUS group were also higher than those of controls at 1, 2 weeks, but the difference was not statistically significant as well. Conclusion: Results of this study indicate that LIPUS may have positive effects on early osseointegration but could not improve the long term stability of dental implants.

• 대한환경공학회지
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• 제28권2호
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• pp.197-206
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• 2006

본 연구에서는 최근 매립지 침출수 처리를 위해 많이 활용되고 있는 막분리 공정에 초음파를 적용하여 투과속도와 막의 세정효율 향상에 미치는 영향인자와 효과에 대하여 살펴보았다. 즉, 중공사 형태의 MF막과 관형의 UF막을 대상으로 초음파의 주파수($40{\sim}120$ kHz), 초음파의 세기($200{\sim}500$ W), 운전압력($0.1{\sim}2.3kg/cm^2$), 초음파 조사시간 등을 변화시키며 투과속도 향상에 미치는 영향을 평가하였다. 1차 처리된 침출수를 이용하여 초기 50 min 동안 막을 오염시킨 다음 70 min 동안 초음파를 조사하여 조사기간과 투과속도의 변화를 관찰하였다. 순수의 투과속도에 대한 투과속도의 회복률(recovery ratio)과 세정직전의 투과속도에 대한 초음파 조사 후 투과속도의 상승률(enhancement ratio)을 이용하여 영향인자를 분석하였다. 동일한 조건에서 막의 초음파 세정에 의한 투과속도 개선 효과는 주파수에 반비례적이며. 초음파의 조사강도에 비례적으로 나타났고, 막의 운전압력이 높으면 세정효과가 지연되며 투과속도의 개선효과도 감소하였다. 또한 10,000과 100,000 MWCO의 UF막에서의 회복율과 상승률은 각각 최대 75-98%와 40-50% 이었으나, $0.1{\mu}m$ MF막에서는 각각 10%와 500%였다. 1차 처리 침출수를 이용한 실험결과로부터 초음파에 의해 발생되는 기계적 진동을 활용한 막세정이 기존의 수세정과 약품세정 대신에 활용가능성이 확인되었다.

• 한국정보전자통신기술학회논문지
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• 제15권6호
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• pp.477-484
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• 2022

본 연구는 집속형초음파자극시스템의 카트리지부를 시료로 사용하여 의료기기 안전성 평가 기준인 GLP(Good Laboratory Practice)에 관한 시험 중 동물실험을 통한 피부 자극 시험 및 피부 감작성시험을 진행하였다. New Zealand White Rabbit 암컷 6마리를 이용하여 IACUC 승인 후 시험을 진행하였으며, 실험기간 동안 사망한 개체 수는 없었으며, 실험동물에서 어떤 이상 증상도 관찰되지 않았다. 극성, 비극성 자극 지수는 모두 '0.0'으로 나타났다. 또한, 피부감작성 평가의 경우 IACUC 승인을 통한 기니피그 30마리를 통하여 대조군 및 실험군으로 나누어 시험검체 및 공시험액을 별도의 희석 없이 용출액 자체를 사용하여 모든 유도 및 유발단계를 적용하였다. 실험결과대조동물의 피부반응 등급은 0등급이었으며, 시험동물의 피부반응에서 1등급 이상을 나타내는 동물은 없었다. 두 시험 결과에서 피부의 이상 증상은 발견되지 않았으며, 인체에 적용하여 환자를 치료할 경우 시험에 사용된 시험재료로부터 피부의 이상 증상이 생기는 질환 등은 나타나지 않는지에 관하여 안정성을 알아 보고자 하였다.

• Imaging Science in Dentistry
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• 제38권2호
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• pp.73-79
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• 2008

Purpose: To assess the internal echo intensity and morphological variability of masseter muscles on ultrasonography and to establish diagnostic criterion of estimation. Materials and Methods: Participants consisted of 50 young adults (male 25, female 25) without pathologic conditions and with full natural dentitions. Sonographic examinations were done with real time ultrasound equipment as Logiq 500 (GE Medical Systems, Seoul, Korea) at 3 parts according to lines paralleling with ala-tragus line as reference line. The thickness and area of masseter muscles according to reference line in cross-sectional images were measured at rest and at maximum contraction. The visibility and width of the internal echogenic intensity of the masseter muscles were also assessed and the muscle appearance was classified into 4 types. Data were statistically analyzed by paired t-test and $x^2$-test. Results: 1. When comparing the thickness and area of masseter muscles concerning with gender, there was few significant difference between right and left sides, however, there were significant differences between males and females except for the greatest thickness of left side. 2. The changes of the greatest thickness and the area between rest and maximum contraction showed that the part of the least thickness manifested more increase at maximum contraction. 3. Each part the manifestations of the internal echogenic intensity of the masseter muscles were different depending on the locations. But there was no statistically significance. Conclusion: Changes of muscles thickness with contraction and internal echogenic intensity with locations showed great disparity within the masseter muscles, which will be diagnostic criteria for pathophysiologic and anatomic changes of masseter muscles.

• Investigative Magnetic Resonance Imaging
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• 제20권4호
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• pp.259-263
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• 2016

Primary diffuse large B-cell lymphoma of the seminal vesicle is an extremely rare disorder, with only two cases reported in the English literature. Here, we present imaging findings of a case of primary diffuse large B-cell lymphoma of the seminal vesicle. On transrectal ultrasonography, the mass presented as a 3.0-cm-sized heterogeneous, hypoechoic lesion in the right seminal vesicle. Computed tomography (CT) revealed a mass with rim-like enhancement in the right seminal vesicle. On magnetic resonance imaging (MRI), the tumor showed iso-signal intensity on T1-weighted images and heterogeneously intermediate-high signal intensity on T2-weighted images. The tumor showed rim-like and progressive enhancement with non-enhancing portion on dynamic scanning. Diffusion restriction was observed in the mass. On fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) imaging, a high standardized uptake value (maxSUV, 23.5) by the tumor was noted exclusively in the right seminal vesicle.

• 대한통합의학회지
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• 제11권1호
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• pp.87-98
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• 2023

Purpose : This study was to verify the effectiveness of eccentric training and to make clinical recommendations on detailed application methods by comparing the effects of changes in acromiohumeral distance (AHD), pain intensity, muscle strength, and functional performance after applying a 12-week eccentric training program (ET group) or concentric training program (CT group) for patients with partial rotator cuff (supraspinatus) tears with moderate to severe shoulder pain. Methods : A total of 29 subjects were assigned to either the "ET group (n=15)" or the "CT group (n=14)" through simple randomization and were measured in the same way at baseline before intervention, 4 weeks and 12 weeks after intervention. All subjects received a physical therapy program 12 sessions 3 times a week for the first 4 weeks, and physical therapy program, 12 sessions a week, from 4 weeks to 12 weeks, for a total 20 sessions. Ultrasound machine was used for AHD, visual analog scale (VAS) was used for pain intensity, electronic hand held dynamometer was used for muscle strength, Korean Constant shoulder score (K-CSS) used for functional performance. Results : AHD, pain intensity, and muscle strength did not show significant differences at 4 weeks, but improved numerically, and showed significant differences at 12 weeks (p<.05), showing superior results in the eccentric training group compared to the concentric training group. Functional performance showed significant changes at both 4 and 12 weeks (p<.05), and excellent results were also found in the eccentric training group. Conclusion : In patients with partial rotator cuff tears with moderate to severe shoulder pain, an eccentric training program increased acromiohumeral distance (AHD), reduced pain, and increased muscle strength. Therefore, it can be clinically presented as an intervention method that can quickly and effectively improve functional performance, which is the ultimate goal of physical therapy.

• Advances in pediatric surgery
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• 제1권2호
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• pp.204-208
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• 1995

Neonatal adrenal hemorrhage is frequently associated with birth trauma or perinatal hypoxia. Hemorrhagic necrosis of the adrenal glands is often found at autopsy and many small lesions are usually asymptomatic. A palpable abdominal mass and jaundice are the usual presenting signs. Ultrasound is very useful in the diagnosis of this lesion; however, if the mass has mixed echoic pattern, magnetic resonance imaging (MRl) is helpful for the differential diagnosis from neuroblastoma. We present the case of a female newborn who was found to have a abdominal mass on physical examination. The patient showed anemia and hyperbilirubinemia. An ultrasonogram disclosed a $3.8{\times}3.0$ cm suprarenal mass with mixed echoic pattern. The mass was initially suspected to be neuroblastoma. An abdominal computed tomogram was not able to differentiate the mass. Magnetic resonance imaging revealed markedly increased signal intensity on T1 and T2-weighted sequences. This finding was consistent with adrenal hemorrhage. Serial sonogram demonstrated the mass that resolved completely by 12 weeks of age.

• 한국음향학회지
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• 제8권4호
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• pp.5-12
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• 1989

초음파 hyperthermia를 이용한 암 치료는 정상세포에 열적 손상을 주지 않으면서 종양 부위만을 적당한 온도로 가열하여야 하며 따라서 종양세포와 정상세포에 대한 정확한 초음파 세기 조절이 필요하게 된다. 본 연구에서 초음파 hyperthermia용 변환기로써 촛점 거리와 집속 범위를 전자적으로 조절할 수 있는 육각환 변환기를 설계, 제작하였으며 위상조 절회로를 이용하여 초음파 hyperthermia 시스템을 구성, 그 음향 특성을 측정하였으며 모의 생체 실험을 수행하였다. 실험 결과 촛점 부근에서 초음파 에너지가 집속되는 것을 확인하였으며 초음과 hyperthermia 시스템으로써의 유용성을 확인하였다.

• 한국전문물리치료학회지
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• 제6권4호
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• pp.1-7
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• 1999

이 연구에서는 24마리의 Japanese White 토끼를 대상으로 양쪽 비골을 인위적으로 골절시킨 후 초음파치료가 골절의 치유에 효과가 있는지를 알아보았다. 초음파 치료 후 대조군의 비골과 실험군의 비골에서의 골소주 비율은 차이가 없었으며 초음파 주파수를 0.875 MHz로 하였을 때와 3 MHz로 하였을 때의 골소주 비율도 차이가 없었다. 따라서 초음파 치료는 토끼의 비골 골절의 치유 효과가 없었다. 그러나 다양한 주파수와 초음파 전달양식을 변화시켰을 때 골절치유 효과가 있는지에 대해서는 지속적인 연구가 필요하다.