• 제목/요약/키워드: Minimal change

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Biomechanical Testing of Anterior Cervical Spine Implants: Evaluation of Changes in Strength Characteristics and Metal Fatigue Resulting from Minimal Bending and Cyclic Loading

  • Kim, Sung-Bum;Bak, Koang-Hum;Cheong, Jin-Hwan;Kim, Jae-Min;Kim, Choong-Hyun;Oh, Seong-Hoon
    • Journal of Korean Neurosurgical Society
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    • 제37권3호
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    • pp.217-222
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    • 2005
  • Objective: To achieve optimal fit of implant, it is necessary to bend the implant during spine surgery. Bending procedure may decrease stiffness of plate especially made of titanium and stainless steel. Typically titanium suffers adverse effects including early crack propagation when it is bent. We investigate whether 6 degree bending of titanium plates would decrease the stiffness after full cyclic loading by comparing with non-bending titanium plates group. Methods: Authors experimented 40 titanium alloy plates of 57mm in length, manufactured by 5 different companies. Total 40 plates were divided into two groups (20 bent plates for experimental group and 20 non-bent plates for control group). Twenty plates of experimental group were bent to 6 degree with 3-point bending technique and verified with image analyzer. Using the electron microscope, we sought for a initial crack before and after 3-point bending. Mechanical testing by means of 6000 cyclic axial-compression loading of 35N in compression with moment arm of 35mm-1.1 Nm was conducted on each plate and followed by the electron microscopic examination to detect crack or fissure on plates. Results: The stiffness was decreased after 6000 cyclic loading, but there was no statistically significant difference in stiffness between experimental and control group. There was no evidence of change in grain structure on the electron microscopic magnification. Conclusion: The titanium cervical plates can be bent to 6 degree without any crack or weakness of plate. We also assume that minimal bending may increase the resistance to fatigue fracture in cervical flexion-extension movement.

패션 트렌드의 전환기(轉換期)에 고찰(考察)한 여성복(女性服) 소비자(消費者)의 최신(最新) 트렌드 수용(受容) - 미니멀리즘과 맥시멀리즘의 영향(影響)이 반영(反映)된 트렌드를 중심(中心)으로 - (An Analysis of the Female Consumers' Acceptance of the New Mode at a Turning Point of Fashion Trend - Focusing on the Minimalism-influenced Trend and Maximalism-influenced Trend -)

  • 신현숙;이주현;서윤정;김지영
    • 패션비즈니스
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    • 제5권4호
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    • pp.73-88
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    • 2001
  • The purpose of this study was to analyze the consumers' acceptance of the new changes in fashion trend and to project the future possibility of them based on the result of the analysis. It was identified in the review of fashion trend that the major change in the recent fashion trend was the turning of focus from 'Minimalism-influenced' to 'Maximalism-influenced'. Total 176 of Korean women, who preferred 'Minimalism-influenced' or 'Maximalism-influenced' style, were sampled and asked to response on a self-report questionnaire with stimuli developed for this study. According to the respondents’ acceptance and preference of either one of the two streams, each respondent was allocated to one of the two groups which were named as 'Minimal-preference group' or 'Maximal-preference group'. The reasons of their preference, traits in trend-related attitude and demographic variables of both groups were analyzed and compared. The degree of clothing involvement and fashion leadership of Maximal-preference group, who accepted the new trend, were found to be significantly higher than those of Minimal-preference group. Maximal-preference group had significantly higher level of income and expenditure on fashion than Minimal-preference group. The motives and reasons for their acceptance of each stream were also analyzed.

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In Vitro X선조사(線照射)가 가토폐포표면(家兎肺胞表面) 활성물질(活性物質)에 미치는 영향(影響) (Effect of X-Irradiation in Vitro on the Pulmonary Surfactant in Rabbits)

  • 조중환;주영은
    • The Korean Journal of Physiology
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    • 제5권1호
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    • pp.51-58
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    • 1971
  • In an attempt to further clarify the effect of X·irradiation on the activity of surfactant in rabbits, X-ray in dose of 900r was irradiated to the lung tissues of rabbits in vitro. Tension-area diagram of the lung extract was recorded automatically by a modified Langmuir-Wilhelmy balance with a synchronized recording system designed in this department. The surface tension of the lung extract was measured at 1,3,5,24 and 48 hours post-irradiation, and the results were compared with the non·irradiated normal group. The result$ thus obtained are summarized as follows: I The maximal surface tension, minimal surface tension, width of the tension·area diagram at the surface area of 40% in the lung extract and stability index of the normal rabbit long extract were 40.73 dynes/cm, 8.96 dynes/cm, 20.71 dynes/cm and 1.28, respectively. II. When 900r of X-ray was irradiated to the lung in vitro, 1) The maximal and minimal surface tensions did not differ noticeably from the normal at 1,3, and 5 post-irradiation hours, but the minimal surface tension increased significantly at 24 and 48 hours Post-irradiation. 2) The width of the tension area at the surface area of 40% showed a tendency of decrease throughout the experiment. 3) The stability index showed no significant change at 1,3 and 5 post-irradiation hours,but at 24 and 48 hours post-irradiation a significant decrease was observed comparing with the control. III. Activity of surfactant was significantly depressed by X·irradiation in vitro especially at 24 and 48 hours post-irradiation.

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Association between Minimal Change Esophagitis and Gastric Dysmotility: A Single-Center Electrogastrography and Endoscopy Study in Children

  • Lim, Kyung In;Shim, Sung Bo;Tchah, Hann;Ryoo, Eell
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제21권1호
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    • pp.20-27
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    • 2018
  • Purpose: Minimal change esophagitis (MCE) is a reflux disease without mucosal breaks, known to be partially associated with abnormal gastric motor function. Electrogastrography (EGG) is commonly applied to assess gastric motor function in a noninvasive fashion. We aimed to determine the relationship between MCE and gastric myoelectrical activity (GME) recorded on EGG in children. Methods: We retrospectively assessed the records of 157 children without underlying disease who underwent both EGG and upper gastrointestinal endoscopy at Gachon University Gil Medical Center between January 2010 and June 2015. The children were stratified according to the appearance of the esophagus (normal vs. MCE). Between-group differences in EGG parameters and their correlation with each MCE finding were statistically analyzed. Results: Only the power ratio, one of the EGG parameters analyzed, differed significantly between the two groups (MCE, $1.68{\pm}3.37$ vs. normal, $0.76{\pm}1.06$; p<0.05), whereas the other parameters, such as dominant frequency, dominant power, and the ratio of abnormal rhythm, showed no differences. Among children with MCE, significant correlations were noted between erythema and power ratio (p<0.05), friability and postprandial dominant frequency (p<0.05), and edema and/or accentuation of mucosal folds and pre-prandial frequency (p<0.05). Helicobacter pylori infection correlated with postprandial arrhythmia (MCE, $33.59{\pm}15.52$ vs. normal, $28.10{\pm}17.23$; p<0.05). EGG parameters did not differ between children with normal esophagus and those with biopsy-proven chronic esophagitis. Conclusion: In children with MCE, gastric dysmotility may affect the development of MCE, manifesting as EGG abnormalities. H. pylori infection may also affect GME. However, larger prospective investigations are needed to confirm these findings.

수종 근관확대 기구를 이용한 근관 형성후의 근관형태 변화에 관한 연구 (A STUDY OF ROOT CANAL SHAPE FOLLOWING CANAL PREPARATION OF VARIOUS CANAL ENLARGING INSTRUMENTS)

  • 최호영;민효기
    • Restorative Dentistry and Endodontics
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    • 제16권1호
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    • pp.74-86
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    • 1991
  • The purpose of this study was to evaluate the resulting root canal angulation and shape change after using various enlarging instruments. The mesial canals (120) of extracted human mandibular 1st and 2nd molars were randomly divided into 6 groups; Control, K-type me, Heliapical me, Canal Master me, sonic and ultrasonic instrumentation group. Vertical angulation of each canal was determined by a straight line through the long axis of canal and another straight line through the apical foramen to intersect at the point where the canal began to leave the long axis of the tooth. By recording and comparing the measured angles of the each set of pre-and postinstrumentation. Then, the roots were sectioned horizontally in the apical, middle, coronal thirds and the canal shapes examined, as was the mesiodistal canal diameter as it relates to the external root surface. The results were as follows: 1. Instrumentation using K-type me group resulted in the highest mean change in angulation ($9.900^{\circ}$) (p < 0.005), while Sonic Air MM 3000 group resulted in the least degree of straightening canals ($8.250^{\circ}$) (p < 0.005). 2. Canal Master file group resulted in the best canal shape at the three levels (P < 0.005). 3. Measured minimal mesial root width produced Heliapical me group at the apical 1/3 level, Sonic Air MM 3000 group at the middle 1/3 level, Heliapical me group at the coronal 1/3 level (P < 0.005). 4. Measured minimal distal root width produced Sonic Air MM 3000 group at the apical 1/3 level (P < 0.05), Heliapical me group at the middle 1/3 level (P < 0.005), Canal Master me group at the coronal 1/3 level (P < 0.005). 5. HeIiapical me group produced more increased canal diameter than any other groups (P < 0.005).

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간(肝)스캔상(上) 체위변동(體位變動)에 따른 간형태(肝形態) 변화(變化)에 대(對)한 고찰(考察) (A Study on the Effects of Position Change on the Liver Shape on Radioisotope Scan)

  • 홍기석;최두혁;양영태;고창순
    • 대한핵의학회지
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    • 제16권1호
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    • pp.49-54
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    • 1982
  • For this study, the authors obtained and examined anterior views of the liver and spleen in two different positions, upright and supine, of 39 normal subjects and 20 patients with hepaticpathology by means of $^{99m}Tc-colloid$ and gamma camera. This examination confirms the following findings. In general, it is shown, left lobe of the liver in upright position becomes longer in height than in supine position, while the distance between lateral margin of the liver and that of the spleen becomes father in with in supine position than in upright position. The upper margin of liver moves more downward in upright position than in supine. It is noticeable that as for 5 cases with severe chronic liver disease, there is minimal alteration of the liver shape between in two positions. The comparison of the both positions for the better liver scan shows the following finding. Prominent caudate and/or left lobe are marked in the upright position in 16 cases out of the total 59, while none is found in the supine. The false cold area in lower part of the liver disappears in 7 cases in the upright position, while only one shows the disappeance of the false cold area in the supine. Left liver margin due to close contact of spleen is blurred in 3 cases in the upright position. In total 23 cases out of 59 support that the upright position is better for the liver scan, while only 4 cases support the supine position is better. These findings support two assumptions. One is that upright view can bo expected more improved resoluton than supine view for liver scan. Second is that minimal change of the liver shape in both views indicate the serious abnormality in the liver.

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천연 복합추출물의 손상모발 개선효과 (Damaged hair improvement effect of natural complex extract)

  • 윤동민;한상필;전용한
    • 한국응용과학기술학회지
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    • 제40권6호
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    • pp.1289-1297
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    • 2023
  • 본 연구에서는 인디안구스베리(암라), 찔레나무, 쏘팔메토열매를 5:1:1 비율로 Complex하고 추출하여 0%, 0.5%, 2.5%, 12.5%, 100%의 NF Complex를 제조하였다. 제조한 NF Complex로 탈색한 시료 모발에 도포 후 손상된 모발과 비교·분석하였다. 개선 효과를 확인하기 위해 인장강도, 광택, 흡광도, 명도를 측정하였다. 측정 결과 인장강도는 증가하였다. 광택은 함량이 100%는 감소하고 나머지 함량은 증가하였다. 흡광도는 손상모와 대조군과의 차이가 있어 개선 효과가 있는 것으로 보인다. 명도는 변화는 있으나 미미하였다. NF Complex의 평균값은 유의미한 차이가 있음을 확인하였으며 추후 다양한 추출방법 및 혼합 비율에 따른 연구가 필요하다고 판단된다.

하위문화 패션스타일 유형(1) (A Study on the Patterns of Subcultural Fashion Style)

  • 양미경
    • 한국의상디자인학회지
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    • 제6권1호
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    • pp.46-54
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    • 2004
  • In this paper, It is examined the patterns of fashion style in the history of subcultural clothing from 1930s to 1960s, focusing on the way each generation resisted the main stream through its styles. The subcultural styles examined and classified in this study are mainly British and American, with a few European and Western Indian styles included. This study understands subcultural style as a way of deviate or resistant expression within a society. The patterns of subcultural styles presented in this study are based on their form of resistance, and they are classified as follows: The pattern is revision, which tries to revise and change the given form by adding new elements. There are two kinds of revision, one is dressing up, which dresses for success, and the other is minimal dressing. Zoot, caribbean, western, teddy boy, rockabilly style are included here. As minimal dressing, there are hipster, beatnik, modernist, mod, rude boy style. In conclusion, it can be said that subcultural style puts the foremost importance on individual freedom. The new and significant development can be found in the fact that subcultural style emerges as a dominating force in our culture. This implies that the energy of a subculture is essential as a formative force of a fashion world.

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로봇수술의 현재와 미래 (The Present and Future of Robotic Surgery)

  • 나군호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 학술대회 논문집 정보 및 제어부문
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    • pp.68-70
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    • 2008
  • Since the beginning of the 21st century, the emergence of innovative technologies made further advances in minimal access surgery possible. Robotic surgery and telepresence surgery effectively addressed the limitations of laparoscopic procedures, thus revolutionizing minimal access surgery. Surgical robots provide surgeons with to technologically advanced vision and hand skills. As a result, such systems are expected to revolutionize the field of surgery. In that time, much progress has been made in integrating robotic technologies with surgical instrumentation. However, robotic surgery will not only require special training, but it will also change the existing surgical training pattern and reshape the learning curve by offering new solutions, such as robotic surgical simulators and robotic telementoring. This article provides an introduction to medical robotic technologies, develops a possible classification, reviews the evolution of a surgical robot, and discusses future prospects for innovation. In the future, surgical robots should be smaller, less expensive, easier to operate, and should seamlessly integrate emerging technologies from a number of different fields. We believe that, in the near future as robotic technology continues to develop, almost all kinds of endoscopic surgery will be performed by this technology.

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체외강력집속초음파치료 (Extracorporeal High Intensity Focused Ultrasound Therapy)

  • 한상석
    • 대한골관절종양학회지
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    • 제11권1호
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    • pp.17-24
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    • 2005
  • 의학의 발달과 더불어 종양에 대한 국소치료는 광범위근치술(extended radical surgery) 로부터 기능보존술(function preserving surgery)로 발달하고 이것은 다시 최소침습술(minimal-invasive surgery)로 발전하여 왔다. 그러나 최근 들어서는 기술의 혁신적인 진보로 비침습적수술법(non-invasive surgery)이 개발되어 감마나이프(gamma knife), 사이버나이프(cyber knife), 및 하이푸나이프(HIFU knife) 등이 출현하게 되었다. 본 논문에서는 이들 중 하이푸나이프를 이용한 체외강력집속초음파치료(extracorporeal high intensity focused ultrasound therapy)에 대하여 발달사, 치료기 구조 및 치료과정, 조직학적 변화와 기전, 임상적용, 장단점 및 전망 등을 살펴보고자 한다.

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