• 한국임상수의학회지
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• 제25권1호
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• pp.1-8
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• 2008

This study is conducted to compare ultrasonographs with plain radiographs in monitoring bone regeneration during reconstruction of critical sized radial defects in dogs. A 15 mm bony defect was taken on each of the eight dog's radius using an electrical saw and an external fixator was applied. The experimental groups were divided into non-treated group(group 1) and $Osteoset^{(R)}$-treated group(group 2). Each fracture site was evaluated using plain radiography and ultrasonography. Radiographic callus formation occurred after $11.50{\pm}1.12$ days in group 1 and $11.50{\pm}0.5$ days in group 2. Neovascularized flow signal could be seen $6.50{\pm}1.5$ days and the vascular signal disappeared after $45.00{\pm}6.16$ days after operation in group 1. Neovascularized flow signal was observed $6.75{\pm}1.78$ days and vascular signal disappeared $23.25{\pm}3.03$ days after surgery which was caused by acoustic shadowing in group 2. Early stages of regeneration were observed more clearly with color Doppler ultrasonography than with plain radiography. Also from the results it is concluded that color Doppler ultrasonography are useful in observing initial stages of bone repair.

• Clinics in Shoulder and Elbow
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• 제26권3호
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• pp.287-295
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• 2023

Background: Posterolateral rotatory instability (PLRI) is a common mechanism of recurrent elbow instability. While the essential lesion is a deficiency in the lateral ulnar collateral ligament (LUCL), there are often associated concomitant bony lesions, such as an Osborne-Cotterill lesions (posterior capitellar fractures) and marginal radial head fractures, that compromise stability. Currently, there is no standard treatment for posterior capitellar deficiency associated with recurrent PLRI. Methods: We conducted a retrospective review of five patients with recurrent PLRI of the elbow associated with a posterior capitellar impaction fracture engaging with the radial head during normal range of motion. The patients were treated surgically with LUCL reconstruction or repair and off-label reconstruction of the capitellar joint surface using a small metal prosthesis designed for metatarsal head resurfacing (HemiCAP toe classic). Results: Five patients (three adolescent males, two adult females) were treated between 2007 and 2018. At a median follow-up of 5 years, all patients had complete relief of their symptomatic instability. No patients had pain at rest, but two patients had mild pain (visual analog scale 1-3) during physical activity. Three patients rated their elbow as normal, one as almost normal, and one as greatly improved. On short-term radiographic follow-up there were no signs of implant loosening. None of the patients needed reoperation. Conclusions: Recurrent PLRI of the elbow associated with an engaging posterior capitellar lesion can be treated successfully by LUCL reconstruction and repair and filling of the capitellar defect with a metal prosthesis. This treatment option has excellent clinical results in the short-medium term. Level of evidence: IV.

• 대한치과보철학회지
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• 제38권5호
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• pp.595-605
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• 2000

Dental ceramics have good aesthetics, biocompatibility, low thermal conductivity, abrasion resistance, and color stability. However poor resistance to fracture and shrinkage during firing process have been limiting factors in their use, particularly in multiunit ceramic restorations. A new method for making all-ceramic crowns that have high strength and low processing shrinkage has been developed and is referred to as the Vita In-Ceram method. This study was performed to investigate the effect of $CeO_2$ addition in borosilicate glasses on the strength of alumina-glass composites. Porous alumina compacts were prepared by slip casting and sintered at $1,100^{\circ}C$ for 2 hours. Dense composites were made by infiltration of molten glass into partially sintered alumina at $1,140^{\circ}C$ for 4 hours. Specimens were polished sequentially from #800 to #2000 diamond disk. and the final surface finishing on the tensile side was received an additional polishing sequence through $1{\mu}m$ diamond paste. Biaxial flexure test was conducted by using ball-on-three-ball method at a crosshead speed of 0.5mm/min. To examine the microstructural aspect of crack propagation in the alumina-glass composites, Vickers-produced indentation crack was made on the tensile surface at a load of 98.0 N and dwell time of 15 sec, and the radial crack patterns were examined by an optical microscope and a scanning electron microscope. The results obtained were summarized as follows; 1. The porosity rates of partially sintered alumina decreased with the rising of firing temperature. 2. The maximum biaxial flexure strength of 423.5MPa in alumina-glass composites was obtained with an addition of 3 mol% $CeO_2$ in glass composition and strength values showed the aspect of decrease with the increase of $CeO_2$ content. 3 The biaxial flexure strength values of alumina-glass composites were decreased with rising the firing temperature. 4. Observation of the fracture surfaces of alumina-glass composites indicated that the enhancement of strength in alumina-glass composites was due to the frictional or geometrical inter-locking of rough fracture surfaces and ligamentary bridging by intact islands of materials left behind the fracture front.

• 대한정형외과스포츠의학회지
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• 제8권2호
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• pp.115-120
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• 2009

목적: 배측 분쇄가 있는 원위부 요골 골절에서 세가지 수술법에 따른 결과를 알아보고자 하였다. 대상 및 방법: 2006년 4월부터 2009년 5월 사이의 60세 이상의 배측 분쇄가 있는 원위부 요골 골절이 있으면서 불안정성을 보인 환자 49명을 대상으로 하였다. 수술 1년 후까지의 방사선학적 추시관찰을 통하여 골절 정복의 유지 여부 및 Mayo Wrist Score를 통한 임상적 결과를 비교하였으며, 일원배치 분산분석(One-Way ANOVA)을 통하여 연관성을 검정하였다. 결과: 세군 모두에서 수술 직후에는 만족스러운 정복을 얻을 수 있었으나, 추시 소견상 외고정장치 단독으로 고정시에는 외고 정장치에 동종골 이식을 추가한 군 및 수장측 잠김 압박 금속판을 사용한 군에 비해서 유의하게 정복 소실이 있음을 확인하였다.(p<0.05) Mayo Wrist Score는 세군 모두에서 의미있는 차이는 없었다. 결론: 배측 분쇄가 심한 원위부 요골의 관절내 골절에서 외고정 장치만 사용한 치료시에는 해면골 결손으로 인한 정복유지의 어려움이 있어 불충분한 치료로 판단된다.

• 한국임상수의학회지
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• 제31권6호
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• pp.523-526
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• 2014

세마리의 개가 골절을 주증으로 내원하였다. 증례 1(1.8 kg의 5개월령 암컷 몰티즈)과 증례 2(3.0 kg의 6개월령 암컷 푸들)는 좌측 후지의 체중부중을 하지 않는 파행을, 증례 3(3.3 kg의 나이를 알 수 없는 암컷 잡종견)은 좌측 전지의 체중부중을 하지 않는 파행을 보였다. 정형외과 검사시 손상받은 부위의 통증, 염발음, 촉진상의 불안정성과 광범위한 연부조직 부종을 보였으며 신경학적 이상소견은 관찰되지 않았다. 방사선 검사상 증례 1와 2에서 좌측 근위 경골 골간단과 비골의 골절이, 증례 3에서는 좌측 근위 요골 골간단과 척골의 골절이 관찰되었다. 모든 증례는 골절편이 짧은 관절주위 폐쇄형 골절이었다. 술 중에는 투시장치를 이용해 2개 또는 3개의 원형고정장치의 적절한 위치에 삽입하였다. 술 후 방사선 사진에서 골절부위의 적절한 배열과 위치를 확인하였다. 방사선학적으로 5주에서 14주 사이에서 골유합이 확인되었고 임플란트의 고정 실패나 핀 주변 감염은 나타나지 않았다. 기능상 결과는 모든 증례에서 매우 좋은 것으로 나타났다. 따라서, 원형외고정장치는 뼈판이나 외고정장치를 사용할 수 없는 짧은 골절편을 가진 관절주의의 골절정복에 성공적으로 이용할 수 있을 거라 사료된다.

• 대한기계학회논문집A
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• 제26권5호
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• pp.932-938
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• 2002

In structural applications, brittle materials such as soda-lime glasses and ceramics are usually subjected to multiaxial stress state. Brittle materials with cracks or damage by foreign object impacts are apt to fracture abruptly from cracks, because of their properities of very high strength and low fracture toughness. But in most cases, the residual strength of structural members with damage has been tested under uniaxial stress condition such as the 4-point bend test. Depending upon the crack pattern developed, the strength under multiaxial stress state might be different from the one under uniaxial. A comparative study was carried out to investigate the influence of stress state on the residual strength evaluation. In comparable tests, the residual strength under biaxial stress state by the ball-on-ring test was greater than that under the uniaxial one by the 4-point bend test, when a small size indendation crack was introduced. In the case that crack having an angle of 90deg. to the applied stress direction, the ratio of biaxial to uniaxial flexure strength was about 1.12. The residual strength was different from crack angles to loading direction when it was evaluated by the 4-point bend test. The ratio of residual strength of 45deg. crack to 90deg. one was about 1.20. In the case of specimen cracked by a spherical impact, it was shown that an overall decrease in flexure strength with increasing impact velocity, and the critical impact velocity for formation of a radial and/or cone crack was about 30m/s. In those cases that relatively large cracks were developed as compared with the case of indented cracks, the ratio of residual strength under biaxial stress state to one uniaxial became small.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.34-42
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• 2015

Feasibility tests for the hydraulic fracturing were conducted in order to secure additional saline groundwater for irrigating to the land-based aquaculture farm. Two boreholes were placed to the aquaculture farm A and B, respectively. A hydraulic fracturing using single packer was applied to major fracture zones within two boreholes. To identify effects of hydraulic fracturing on securing additional saline groundwater, some selective methods including well logging methods, pumping tests, and groundwater quality analysis were commonly applied to the boreholes before and after the hydraulic fracturing. Enlarging/creating fracture zones, increasing water contents in bedrock near boreholes, and increasing transmissivity were observed after the hydraulic fracturing. Even though the hydraulic fracturing could be an alternative to secure additional saline groundwater to the land-based aquaculture farm, salinity of the groundwater did not meet optimal thresholds for each fingerling in two farms: Fresh submarine groundwater discharge flowed the more into borehole of the farm A that resulted in decreasing a salinity value. Increased saline groundwater quantity in the borehole of the farm B rarely affect to the salinity. Although salinity problem of groundwater limited its direct use for the farms, the mixing with seawater could be effectively used for the fingerlings during the early stage. A horizontal radial collector well placed in the alluvial layer could be an alternative for the farms as well.

• 한방재활의학과학회지
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• 제27권4호
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• pp.55-65
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• 2017

Objectives The purpose of this review is to analyze results of case studies and controlled studies about Carthmi-Flos pharmacopuncture. Based on the review, authors desire to suggest the study model including precise information and evident the effect of Carthmi-Flos pharmacopuncture objectively in treating clinical disorders. Methods We search 44 studies about Carthmi-Flos pharmacopuncture from 6 Korean web databases, using words 'Carthmi-Flos pharmacopuncture' in Korean alphabet. This study had been conducted throughout 1 month (July, 2017). We selected case studies and controlled trials in investigated 44 thesis, excluding experimental research and thesis not using the Carthmi-Flos pharmacopuncture for major treatment. Results We analyze 13 case reports and 7 controlled trials. As a result, Carthmi-Flos Pharmacopuncture was used mostly in musculoskeletal, neurological diseases. But this can be applied to internal diseases. Disorders reported effectively were carpal tunnel syndrome, degenerative knee joint arthritis, posterior neck pain, low back pain, radial nerve palsy, shoulder pain, lumbar compression fracture, alopecia areata, chronic daily headache, duverney fracture, oligomenorrhea, cervical disc herniation, rheumatoid arthritis and cervical headache. Conclusions As we analyzed, Carthmi-Flos pharmacopuncture is specifically effective in musculoskeletal and neurologic diseases. But there are various problems in study design. To design accurately, the study design should include much more specific information. And the result can be more precise by excluding other methods.

• 한국해양공학회지
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• 제3권2호
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• pp.125-137
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• 1989

To check technical improvement in the soundness and strength of 12% Cr steel rotor, a 25 tons of rotor with 65 tons of ingot was made in real size and was cut to pieces to take test samples, and the various mechanical tests such as impact, tensile, creep, and fatigue were carried out. The strengths are compared with those of 1% Cr-Mo-V rotor of same size. Microstructures of the samples are examined and reviewed. The results can be summarized as follows. 1) Fracture appearance transition temperatures are 80.deg. C at the center part and 60.deg. C near surface of 12% Cr rotor, and 8.deg. C near surface of 1% Cr-Mo-V rotor. 2) Comparative rapid softening occurs at higher temperatures above 600.deg. C for 12% Cr steel and 550.deg. C for 1% Cr-Mo-V steel in tension tests. 3) Fatigue crack propagation rate of 12% Cr steel is almost same as that of 1% Cr-Mo-V steel at the same corresponding surface part of the rotors. The crack growth rate of center part of 12% Cr rotor is faster than near surface part of the rotor, and the crack growth rate at the load condition of R=0.04 is slower than that of the load condition of R=0.5 for both 12% Cr steel and 1% Cr-Mo-V steel. 4) Crack growth rate of radial direction near surface of 12% Cr rotor is faster than that of transverse direction at the same part because of the difference in residual stresses. 5) Both creep and fatigue strengths of 12% Cr steel are superior to those of 1% Cr-Mo-V steel and the difference is thought the effect of climb and glide controlled creep by solid solution of alloying elements and dispersion of carbides.

• 한국해양공학회지
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• 제3권2호
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• pp.625-625
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• 1989

To check technical improvement in the soundness and strength of 12% Cr steel rotor, a 25 tons of rotor with 65 tons of ingot was made in real size and was cut to pieces to take test samples, and the various mechanical tests such as impact, tensile, creep, and fatigue were carried out. The strengths are compared with those of 1% Cr-Mo-V rotor of same size. Microstructures of the samples are examined and reviewed. The results can be summarized as follows. 1) Fracture appearance transition temperatures are 80.deg. C at the center part and 60.deg. C near surface of 12% Cr rotor, and 8.deg. C near surface of 1% Cr-Mo-V rotor. 2) Comparative rapid softening occurs at higher temperatures above 600.deg. C for 12% Cr steel and 550.deg. C for 1% Cr-Mo-V steel in tension tests. 3) Fatigue crack propagation rate of 12% Cr steel is almost same as that of 1% Cr-Mo-V steel at the same corresponding surface part of the rotors. The crack growth rate of center part of 12% Cr rotor is faster than near surface part of the rotor, and the crack growth rate at the load condition of R=0.04 is slower than that of the load condition of R=0.5 for both 12% Cr steel and 1% Cr-Mo-V steel. 4) Crack growth rate of radial direction near surface of 12% Cr rotor is faster than that of transverse direction at the same part because of the difference in residual stresses. 5) Both creep and fatigue strengths of 12% Cr steel are superior to those of 1% Cr-Mo-V steel and the difference is thought the effect of climb and glide controlled creep by solid solution of alloying elements and dispersion of carbides.