• 제목/요약/키워드: center symmetry

검색결과 257건 처리시간 0.032초

편측 구순열비의 교정술: Rotation Advancement 원칙에 근거한 Mulliken의 방법 (Repair of Unilateral Cleft Lip and Nose: Mulliken's Modification of Rotation Advancement)

  • 정영수;이규태;정휘동
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제34권2호
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    • pp.133-139
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    • 2012
  • 모든 환자들은 구순접합술을 시행 받았고 구순 및 구개열 유아들은 악정형장치인 Latham을 사용하였다. 수술의 기술적 변화들은 앞서 설명하였다. Columella 부위의 높은 rotation과 releasing incision은 내측 입술 부위를 충분히 길게 해주고, advancement flap이 phitral column 상방으로 최소로 침범되게 하여 균형적인 입술을 만들 수 있다. 또한 구륜근을 외번시켜 philtral ridge를 형성하고, 작은 unilimb Z-plasty을 구순측 Cupid's bow handle 높이에 맞게 시행 후, vermilion-cutaneous junction에서부터 상방으로 cutaneous closure 시행한다. 변위된 alar cartilage는 nostril rim incision을 통해 동측 upper lateral cartilage에 매달며, Alar base는 anterior-caudal septum의 위치, sill의 설정 그리고 외측 vestibular web 제거를 포함하여 3차원적으로 설계하여 치료해야 한다. 이번에 소개한 Mulliken의 치료법이 환자들과 외과의사들에게 많은 도움이 되기를 바란다.

Ribosomal Crystallography: Peptide Bond Formation, Chaperone Assistance and Antibiotics Activity

  • Yonath, Ada
    • Molecules and Cells
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    • 제20권1호
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    • pp.1-16
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    • 2005
  • The peptidyl transferase center (PTC) is located in a protein free environment, thus confirming that the ribosome is a ribozyme. This arched void has dimensions suitable for accommodating the 3'ends of the A-and the P-site tRNAs, and is situated within a universal sizable symmetry-related region that connects all ribosomal functional centers involved in amino-acid polymerization. The linkage between the elaborate PTC architecture and the A-site tRNA position revealed that the A-to P-site passage of the tRNA 3'end is performed by a rotatory motion, which leads to stereochemistry suitable for peptide bond formation and for substrate mediated catalysis, thus suggesting that the PTC evolved by genefusion. Adjacent to the PTC is the entrance of the protein exit tunnel, shown to play active roles in sequence-specific gating of nascent chains and in responding to cellular signals. This tunnel also provides a site that may be exploited for local co-translational folding and seems to assist in nascent chain trafficking into the hydrophobic space formed by the first bacterial chaperone, the trigger factor. Many antibiotics target ribosomes. Although the ribosome is highly conserved, subtle sequence and/or conformational variations enable drug selectivity, thus facilitating clinical usage. Comparisons of high-resolution structures of complexes of antibiotics bound to ribosomes from eubacteria resembling pathogens, to an archaeon that shares properties with eukaryotes and to its mutant that allows antibiotics binding, demonstrated the unambiguous difference between mere binding and therapeutical effectiveness. The observed variability in antibiotics inhibitory modes, accompanied by the elucidation of the structural basis to antibiotics mechanism justifies expectations for structural based improved properties of existing compounds as well as for the development of novel drugs.

경부 전산화단층촬영상에서 후두계측 (Laryngeal Measurement on Neck CT)

  • 유영채;오재식
    • 대한기관식도과학회지
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    • 제2권1호
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    • pp.71-81
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    • 1996
  • 1992년 1월부터 1994년 12월까지 전남대학병원에서 경부 전산화단층촬영을 시행한 환자 중 경부에 종양, 염증성 질환 등 기질적인 질환 및 경부외상의 기왕력이 없는 45례의 경부 전산화단층촬영상에서 캘리퍼스 및 분도기를 이용하여 후두의 좌우 대칭성, 설골 및 성문의 위치, 후두의 길이 및 좌우 갑상 연골이 이루는 각도 등을 계측하여 다음과 같은 결과를 얻었다. 1. 대부분의 경우에서 후두구조는 어느 정도 비대칭성을 보였고 우측편위가 좌측편위보다 많았으며 성별 및 연령별에 따라 의의있는 차이는 없었다. 2. 설골의 높이는 제 2-3경추 부위에서 제 5-6경추 부위까지 위치하고 있었고 제 3-4경추 부위 가 가장 흔한 부위였다. 3. 성문의 높이는 제 4경추 부위에서 제 6-7경추간까지 위치하고 있었고 제 5경추 부위가 가장 흔한 부위였다. 4. 양측 갑상연골이 이루는 각도는 58도에서 100도까지 다양하였고 평균 81.5도였으며, 평균각도는 남성에서 77.24도, 여성에서 87.88도였다.

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Theoretical Calculations of Infrared Bands of CH3+ and CH5+

  • Matin, Mohammad A.;Jang, Joonkyung;Park, Seung Min
    • Bulletin of the Korean Chemical Society
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    • 제34권7호
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    • pp.2051-2055
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    • 2013
  • Existing theoretical calculations predict that infrared spectra of the two most fundamental reactive carbo-ions, methyl cation $CH{_3}^+$ with $D_{3h}$ symmetry and protonated methyl cation $CH{_5}^+$ with $C_s(I)$, $C_s(II)$, and $C_{2v}$ symmetries, appear together in the 7-${\mu}m$ region corresponding to the C-H bending modes. Vibrational band profiles of $CH{_3}^+$ and $CH{_5}^+$ have been compared by ab initio calculation methods that use the basis sets of MP2/aug-cc-pVTZ and CCSD(T)/cc-pVTZ. Our results indicate that the bands of rotation-vibration transitions of $CH{_3}^+$ and $CH{_5}^+$ should overlap not only in the 3-${\mu}m$ region corresponding to the C-H stretching modes but also in the 7-${\mu}m$ region corresponding to the C-H bending modes. Five band intensities of $CH{_5}^+$ among fifteen vibrational transitions between 6 and 8 ${\mu}m$ region are stronger than those of the ${\nu}_2$ and ${\nu}_4$ bands in $CH{_3}^+$. Ultimate near degeneracy of the two bending vibrations ${\nu}_2$ and ${\nu}_4$ of $CH{_3}^+$along with the stronger intensities of $CH{_5}^+$ in the three hydrogen scrambling structures may cause extreme complications in the analysis of the high-resolution carbo-ion spectra in the 7-${\mu}m$ region.

탄탈륨 집합조직 발달에 대한 교차압연의 영향 (Effect of Cross Rolling on the Development of Textures in Tantalum)

  • 강전연;박성원;박준영;박성준;송이화;박성택;김광련;오경원
    • 열처리공학회지
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    • 제31권6호
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    • pp.275-282
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    • 2018
  • Two different modes of rolling were applied to control the texture development in tantalum sheet. In the conventional uni-directional rolling, the typical rolling textures of a body-centered cubic metal which was primarily composed of <110>//(rolling direction) was developed. In a cross rolling where the specimen was rotated by $90^{\circ}$ between each pass, the rotated cube components, i.e. {100}<011> were greatly reinforced. The prediction of lattice rotation by the full-constraint Taylor model showed that the high stability and the symmetry of the rotated cube components caused their strengthening in cross-rolling. The two specimens were heated to $1,100^{\circ}C$ at $9^{\circ}C/min$and held for 1 hour for annealing, then cooled to room temperature in atmosphere. In spite of the significant difference in the deformation textures, the annealing textures were very similar. They developed strong <111>//(plane normal) components with negligible intensity at the rotated cube components, which was attributed to the negligible capability of the latter components to provide effective recrystallized grains.

Hinge Axis Point에 관한 연구 (A Study of the Hinge Axis Point)

  • 정금태
    • 대한치과보철학회지
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    • 제22권1호
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    • pp.72-78
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    • 1984
  • The notion that the axis of the shaft of the articulator must coincide the patient's mandibular transverse axis tells us the importance of locating the axis precisely. When using kinematic axis to transfer a cast to an articulator, the anatomic asymmetry of the contralateral points will result in certain distortion when the axis transferred to an articulator where the mechanical axis produces symmetry. In this study, after locating the true hinge axis point with Denar hinge axis locator, the discrepancies between true hinge axis point and arbitrary hinge axis point that was 13mm anterior from the posterior margin of center of trangus to the outer canthus of eye were measured. And the discrepancies between left and right true hinge axis point in the superoinferior and anteroposterior directions were measured. For this study, 20 dental students who have no missing teeth and no difficulties of mandibular movement were selected. Upper and lower cast of subjects were mounted on Denar Mark II articulator uisng Denar Slidematic face-bow and centric relation record for the measurement of discrepancies between left and right true hinge axis points. The results obtained as follows. 1. The mean distance from the arbitrary hinge axis point to the true hinge axis point was as follows. Right: horizontal distance; 1.99mm, vertical distance; 2.12mm, linear distance; 3.36 mm. Left: horizontal distance; 1.39mm, vertical distance; 2.06mm, linear distance; 2.09mm. Total: horizontal distance; 1.69mm, vertical distance; 2.09mm linear distance; 3.06 mm. 2. The 87.5% of true hinge axis points were within 5mm of the arbitrary hinge axis point. 3. The mean discrepancies between the right and left hinge axis point were 2.92mm in superoinferior direction and 4.74mm in anteroposterior direction. 4. When transferring the axis to the articulator, anatomic asymmetry between right: and left axis point produces in dislocation of cast on the articulator, and undesirable shift in esthetic tooth position will be resulted.

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역동적 기하 환경에서 중등 영재학생들의 합동변환 활동에 대한 발생적 분해 (Gifted Middle School Students' Genetic Decomposition of Congruent Transformation in Dynamic Geometry Environments)

  • 양은경;신재홍
    • 대한수학교육학회지:수학교육학연구
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    • 제25권4호
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    • pp.499-524
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    • 2015
  • 본 연구는 GSP 환경에서 합동변환 개념에 대한 발생적 분해를 제시하고, 중학교 2학년 영재학급 학생 4명을 대상으로 참여 학생들의 합동변환 개념에 대한 발생적 분해가 어떻게 드러나고 변화하는지, 또한 드래그 활동이 합동변환 개념의 이해에 어떤 역할을 하는지 알아보고자 하였다. 합동변환 개념을 이해할 때, 학생들은 중요한 두 스키마인 '한 점 이동 스키마'와 '변환 이동 스키마'를 동시에 고려하였으며, 한 학생이 어느 한 스키마를 선호하거나 치중하여 사용하기 보다는 두 스키마를 모두 고려하되 방향을 정하기 어려운 과제일수록 '한 점 이동 스키마'에 더 의존하는 경향을 보였다. Law(1991)의 '한 점 이동 스키마'의 집약화에 따른 '도형 이동 스키마'는 학생들에게 관찰되지 않았으며, 합동변환의 합성을 완벽하게 이해하기 위해서 조정뿐만 아니라 가역적 사고가 더 필요하였다. 또한, 합동변환 개념을 이해하는 과정에서 학생의 드래그 활동은 정의역과 치역을 평면 위의 점으로 확장하는데 도움이 되었고, 벡터, 회전의 중심, 대칭축의 역할을 인식하는데 도움이 되었다.

Trypan blue 도포를 사용한 누드 마우스와 흰쥐에서 경혈자리 찾기와 DiI 추적 법 (Visualization of potential acupuncture points in rat and nude mouse and DiI tracing method)

  • 이병천;엄기훈;배경희;강대인;소광섭
    • 대한약침학회지
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    • 제12권3호
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    • pp.25-30
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    • 2009
  • Objectives: To find the potential acupuncture points by using Trypan blue staining on the skin of rat and Nude mouse. Methods: 0.4% Trypan blue was applied to the skin of rat or Nude mouse previously treated by surfactant. Washing by warm saline was followed after enough application of trypan blue and surfactant. Frequency of Trypan blue application should be varied to the experimental animals' condition for visualizing significant spots. Results: Blue spots appeared roughly in symmetry along kidney meridian or stomach meridian. Several spots outside of kidney or stomach meridian were also observed; however, the detail stereoscopic images of those blue spots were slightly different according to the position blue-colored. DiI signals were visualized along blood vessel after DiI injection into the Trypan blue-visualized blue spots. Conclusion: Our method to visualize the potential acupuncture points as a blue spot on rat and Nude mouse skins may contribute to the next step for finding specific flowing channels among blue spots.

The effect of treadmill gait training with patellar taping on gait abilities in chronic stroke patients

  • Shin, Jin;Chung, Yijung
    • Physical Therapy Rehabilitation Science
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    • 제4권2호
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    • pp.94-102
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    • 2015
  • Objective: The purpose of this study is to investigate the effect of treadmill gait training with patellar taping on gait abilities in chronic stroke patients. Design: Randomized controlled trial. Methods: Thirty chronic stroke patients who have been diagnosed at least six months or before were recruited in Gyeongin Rehabilitation Center Hospital, located in Incheon. Patients who were enrolled in this study were randomized to experimental group (n=15) or control group (n=15). Treadmill with patella taping training group patients were applied with patellar taping when they were being trained on a treadmill. Control group patients were being trained on a treadmill without any kind of taping. Gait parameters were measured with a GAITRite$^{(R)}$ system which evaluated gait performances. Gait trainings were done for 30 min/day, 5 days/week, for 4 weeks. Results: After treadmill training, treadmill with patella taping training group showed a significant improvement in gait abilities, including velocity, cadence, paretic and non-paretic step length, and double support period (p<0.05). However, in general treadmill group, there were no significant differences in gait parameters except velocity and cadence. There was a significant difference in gait performance in the experimental group compared with the control group, except for the gait symmetry ratio (p<0.05). Conclusions: According to this result of this study, it seems that application of patellar taping in treadmill gait training for chronic stroke patients significantly improved gait abilities of these patients. Also, we can conclude that patella taping is thought to be useful in real clinical settings where there are many chronic patients who are in need of improvement in their gait abilities.

보급형 3D 프린터로 제작한 쇄골 골절 모델을 이용한 정형외과 수술에 대한 유용성과 활용가능성 평가 (Evaluation of Usefulness and Availability for Orthopedic Surgery using Clavicle Fracture Model Manufactured by Desktop 3D Printer)

  • 오왕균
    • 대한방사선기술학회지:방사선기술과학
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    • 제37권3호
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    • pp.203-209
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    • 2014
  • 쇄골 CT 영상을 이용하여 보급형 3D 프린터로 제작된 모델로 사전 수술계획을 실시하여 수술효율에 대한 유용성과 임상적 활용가능성을 평가하였다. CT 영상을 Open Source DICOM Viewer Osirix에서 STL 파일로 변환하여 FDM 와이어 척층가공방식의 보급형 3D 프린터로 환자 맞춤형 쇄골 골절 모델을 제작하였다. 또한, 인체의 좌우 대칭 특성을 이용하여 골절되지 않은 반대편 쇄골의 STL 파일을 Mirror 기법으로 손상되기 전 원형의 모델을 복원, 제작하였다. 모델은 골절의 위치와 크기, 정도가 동일하게 출력되었다. 영상의학과에서 적은 비용과 시간으로 직접 제작한 쇄골 모델을 활용하면 수술시 2차 손상을 줄이고, 최소 침습적 피하금속판 골유합술(MIPO)로 수술효율을 높일 수 있어 임상적으로 유용할 것으로 생각된다.