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미숙아에서 인공호흡기 치료 중 발생한 긴장성공기심장막증 2예 (Two Cases of Tension Pneumopericardium in Mechanically Ventilated Preterm Infants)

  • 맹세현;서현주;신정희;정지미;김진규;유혜수;안소윤;김은선;장윤실;박원순
    • Neonatal Medicine
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    • 제18권1호
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    • pp.153-157
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    • 2011
  • 공기심장막증은 신생아의 공기누출의 종류 중 가장 드문 형태이지만 신생아 심장 압전의 가장 흔한 원인이 되며 대부분 신생아 호흡곤란 증후군으로 기계 환기 치료를 받는 미숙아에서 발생하고 사망률은 70-80%에 이른다. 공기심장막증은 심혈관계 허탈을 초래하고 환아를 사망에 이르게 할 수 있으며 생존하더라도 뇌출혈 등의 뇌 손상이 발생하여 발달지연 등의 신경학적 후유증을 남길 수 있으므로 신속한 발견과 중재 시술이 중요하다. 저자들은 공기심장막증 이후 심장막천자 만으로 증상이 호전되었던 경우와 심장막관 삽입술이 필요했던 경우를 각각 1예씩 경험하여 이를 보고하는 바이다.

p63 Cytoplasmic Aberrance is Associated with High Prostate Cancer Stem Cell Expression

  • Ferronika, Paranita;Triningsih, F.X. Ediati;Ghozali, Ahmad;Moeljono, Abraham;Rahmayanti, Siti;Shadrina, Arifah Nur;Naim, Awang Emir;Wudexi, Ivan;Arnurisa, Alfa Monica;Nanwani, Sandeep Tarman;Harijadi, Ahmad
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권5호
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    • pp.1943-1948
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    • 2012
  • Introduction: Prostate cancer in Indonesia is the $3^{rd}$ ranking cancer among males and the $5^{th}$ rank for their cancer mortality. Prognostic markers that can identify aggressive prostate cancer in early stages and help select appropriate therapy to finally reduce the mortality are therefore urgently needed. It has been suggested that stem cells in the prostate gland have a role in initiation, progression, and metastasis of cancer, although controversy continues to exist. Maintenance of normal stem cell or reserve cell populations in several epithelia including prostate has been shown to be regulated by p63 and alteration of p63 expression is considered to have an oncogenic role in prostate cancer. We hypothesize that the expression of cytoplasmic aberrance of p63 is associated with high ALDH1A1 expression as a cancer stem cell marker, thus leading to progression of prostate cancer. Methods: Using a cross-sectional study during two years (2009-2010), a total of 79 paraffin embedded tissues of benign prostatic hyperplasia, PIN prostatic intraepithelial neoplasia, low and high Gleason score prostate cancer were investigated using immunohistochemistry. Associations between cytoplasmic p63 and ALDH1A1, as well as with pathological diagnosis, were analyzed by Chi-Square test using SPSS 15.0. Links of both markers with cell proliferation rate (KI-67) and apoptotic rate (cleaved caspase 3) were also analyzed by Kruskal-Wallis test. Results: The mean age of patient at the diagnosis is 70.0 years. Cytoplasmic aberrance of p63 was associated with ALDH1A1 expression (p<0.001) and both were found to have significant relationships with pathological diagnosis (including Gleason score), (p=0.006 and p<0.001 respectively). Moreover, it was also found that higher levels of cytoplasmic p63 were significantly associated with the frequency of proliferating cells and cells undergoing apoptosis in prostate cancers (p=0.001 and p=0.016 respectively). Conclusion: p63 cytoplasmic aberrance is associated with high ALDH1A1 expression. These components are suggested to have an important role in prostate cancer progression and may be used as molecular markers.

Association of Methylation of the RAR-β Gene with Cigarette Smoking in Non-Small Cell Lung Cancer with Southern-central Chinese Population

  • Li, Wen;Deng, Jing;Wang, Shuang-Shuang;Ma, Liang;Pei, Jiang;Zeng, Xiao-Xi;Tang, Jian-Xin
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권24호
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    • pp.10937-10941
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    • 2015
  • Pathogenesis of lung cancer is a complicated biological process including multiple genetic and epigenetic changes. Since cigarette smoking is confirmed as the most main risk factor of non-small cell lung cancer (NSCLC), the aim of this study was to determine whether tobacco exposure plays a role in gene methylation. Methylation of the RAR-${\beta}$ gene were detected using methylation-specific polymerase chain reaction in DNA from 167 newly diagnosed cases with NSCLC and corresponding 105 controls. A significant statistical association was found in the detection rate of the promoter methylation of RAR-${\beta}$ gene between NSCLC and controls ($x^2$=166.01; p<0.01), and hypermethylation of the RAR-${\beta}$ gene was significantly associated with smoking status (p=0.038, p<0.05). No relationship was found between RAR-${\beta}$ gene methylation and pathologic staging including clinical stage, cell type, gender and drinking (p>0.05), and the methylation of RAR-${\beta}$ gene rate of NSCLC was slightly higher in stages III+IV (80.0%) than in I+II (70.8%). Similar results were obtained for methylation of the RAR-${\beta}$ gene between squamous cell carcinoma (77.9%) and other cell type lung cancer (73.9%). These results showed that the frequency of methylation increased gradually with the development of clinical stage in smoking-associated lung cancer patients, and tobacco smoke may be play a potential role in RAR-${\beta}$ gene methylation in the early pathogenesis and process in lung cancer, particularly squamous cell carcinoma. Aberrant promoter methylation is considered to be a promising marker of previous carcinogen exposure and cancer risk.

Orthopantomograph에 의(依)한 혼합치열상(混合齒列像)의 해석(解析)에 관(關)한 연구(硏究) (A STUDY ON AN INTERPRETATION OF THE ORTHOPANTOMOGRAPH IN THE MIXED DENTITION)

  • 김광원
    • 대한치과교정학회지
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    • 제12권2호
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    • pp.145-154
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    • 1982
  • Plaster models were constructed and orthopantomographs were taken for 86 male and 70 female primary school pupils, whose upper and lower permanent 4 incisors and 1st molars were completely erupted without crowding; whose deciduous canines and molars were found almost uniformly even without any visible tooth fractures, dental caries or restorations on proximal surfaces of the teeth. Certain reference points on the orthophantomograph were set up and measured and the values were compared with actual or predicted values from the models. The following results were obtained: 1. In regards to available space, the values from the orthopantomograph were greater than the values from the models by a mean of 3.24% on the upper and 10.06% on the lower for males; 3.05% on the upper and 10.01% on the lower for females. 2. In regards to total mesiodistal widths of permanent canine, 1st and 2nd premolars, the values from the orthopantomograph were greater than the presumed values based on the size of lower permanent 4 incisors from the models by a mean of 18.50% on the upper and 24.09% on the lower for males; 14.54 on the upper and 20.51% on the lower for females. 3. Comparing the magnified values of total mesiodistal widths of permanent canine, 1st and 2nd premolars with those of available space, the regression constants of regression equation (Y = a + bX) between them were a=3.2336, b=0.6533 on the upper and a=5.0138, b=0.3290 on the lower for males; a=2.5994, b=0.6521 on the upper and a=3.0113, b=0.6586 on the lower for females. 4. The correlation coefficients between the magnified values of available space and permanent canine, 1st and 2nd premolars were moderately positive as 0.6474 in the upper and 0.505 on the lower for males; 0.6493 on the upper and 0.6183 on the lower for females. 5. In regards to magnified values of the available space from the orthopantomographs there were no significant difference between sexes, (P>0.05) but of the total mesiodistal widths of permanent canine, 1st and 2nd premolars, a significant difference between sexes was found.(p<0.01).

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직접 디지탈 방사선 촬영시스템과 Ektaspeed 및 Ektaspeed Plus 필름을 이용한 방사선 사진용 디지탈 영상시스템과의 비교 연구 (COMPARATIVE STUDY OF DIRECT DIGITAL RADIOGRAPHIC SYSTEM WITH FILM-BASED DIGITAL IMAGING SYSTEM USING EKTASPEED AND EKTASPEED PLUS FILM)

  • 도정주;김은경
    • 치과방사선
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    • 제25권1호
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    • pp.51-70
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    • 1995
  • The purpose of this investigation was to compare the direct digital radiographic system with film-based digital imaging system using Ektaspeed and Ektaspeed Plus film with respect to image characteristics and detectability and evaluate the sensor noise with the use of subtraction method. Direct digital radiographic system which used was Sens-A-Ray system(Regam Medical Systems, Sundsvall, Sweden) and film-based digital imaging system was composed of Macintosh II ci computer, high resolution Sony XC-77 CCD camera and intraoral x-ray film(Kodak Ektaspeed film, Kodak Ektaspeed Plus film). Images were taken by using CCD sensor of Sens-A-Ray system, Ektaspeed film and Ektaspeed Plus film with variable exposure time(0.06s, 0.1s, 0.16s, 0.2s, 0.3s, 0.4s, 0.5s, 0.6s, O.8s, LOs), 5 times at each exposure time. And then ektaspeed films and ektaspeed plus films were digitized using CCD camera. Image groups were divided into 3 groups; Sens-A-Ray group(direct digital radiographic system), Ektaspeed group and Ektaspeed Plus group (film-based digital imaging system) They were assessed by the following three aspects; image density, image contrast and detectability and sensor noise of Sens-A-Ray system was also evaluated. The results were as follow : 1. S group showed higher density than E , EP group except at the low exposure time(p<0.01). 2. S group showed higher contrast than E,EP group except at the high exposure time(p<0.01). 3. All groups showed good detectability at the each proper exposure time. Lowest exposure time which shows maximum detectability in S,EP group(0.5s) was lower than that in E group(0.6s). 4. Sensor noise of Sens-A-Ray system generally increased according to exposure time. On the basis of the above results, it was considered that Sens-A-Ray system could show higher speed, higher contrast than Ektaspeed, Ektaspeed Plus film except at too high and low exposure time and the same detectability as the conventional intraoral film.

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Streptozotocin유도 당뇨병이 백서하악 절단과두 치유에 미치는 영향의 실험적 연구 (REMODELING PROCESS OF THE STREPTOZOTOCIN-INDUCED DIABETIC RAT'S RESECTED CONDYLE)

  • 김원철;황의환;이상래;홍정표
    • 치과방사선
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    • 제24권2호
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    • pp.263-274
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    • 1994
  • The purpose of this study was to investigate the remodeling process of the streptozotocin-induced diabetic rat's resected condyle. This experiment was performed with male Sprague-Dawly strain rats weighing approximately 250 gm, which were rendered diabetic by an intravenous injection of streptozotocin(70㎎/㎏ body weight). After condylectomy, experimental rats were serially terminated on the 1st week, the 2nd week, the 3rd week, and the 4th week. The following termination, the mandibles were dissected out to make specimens. Each mandibular condyle was radiographed with Hitex HA-80(Hitex Co., Ltd. Japan). In addition to radiographic observation, the mandibular condyles, further decalcified and embedded in paraffin, were sectioned and stained with Hematoxylin and Eosin, Toluidine blue and Masson's trichrome. They were observed with a light microscope and a polarizing microscope. The results were as follows. 1. Soft X-ray radiograms revealed proliferation of bone after 1 week in both groups. Irregularly repaired bones and dense trabeculae were clearly observed in experimental group. 2. The resected condyles were repaired by intramembraneous and endochondral bone formation in both groups. 3. Bone tissue repair was initiated from the adjacent margin of resected bone, and cartilaginous tissues were observed at the top of repaired bone in both groups. 4. The number of osteoblasts of experimental group was small, compared with control group. Each osteoblast was small and flat. The thin trabeculae were irregularly formed. 5. Collagens of bone were gradually matured in both groups, but the degree of maturation was lower in experimental group. 6. Fibrous tissues covered the upper parts of repaired bone were densely arranged in the both groups. Conclusively, atrophied osteoblasts, immature collagen of bone, and thin and irregular trabeculae which were characterized in the diabetes experimental group showed diabetes disturbed osteoblastic function and caused disturbance of remodeling process of bone.

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이종 타겟을 지닌 대향 타겟 스퍼터링 방법으로 제작된 AZO 박막의 광학적·전기적 특성에 관한 연구

  • 야오리타오;서성보;배강;김동영;최명규;김화민
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.337-337
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    • 2014
  • 투명 전도성 산화물(transparent conductive oxide: TCO) 박막은 높은 투과율과 낮은 비저항 덕분에 LCD (liquid crystal display), PDP (plasma display panel), OLED (organic light emitting display) 등 평판 디스플레이에 널리 사용되고 있다. 현재 양산되고 있는 ITO (indium tin oxide)는 90% 이상의 높은 투과율과 우수한 전도성으로 인해 TCO 박막 가운데서 디스플레이 산업에서 가장 널리 쓰이고 있다. 그런데, ITO의 인듐산화물에 의한 간질성 폐렴(interstitial pneumonia)의 유발 위험이 있다든가, 인듐의 매장량이 적어 원자재 가격이 비싼 단점도 가지고 있다. 이에 최근 ITO를 대체할 수 있는 TCO물질로 많은 연구가 이루어지고 있는데, 특히 AZO (aluminum-doped zinc oxide)는 그 중 대표적인 대체물질로서 독성이 없고 가격도 저렴하여 많은 관심이 증폭되고 있다. 현재 AZO는 sol-gel 방법이나 CVD (chemical vapor deposition) 또는 스퍼터링 방법 등으로 증착되고 있다. 본 연구에서는 두 개의 이종타겟(hetero target)을 장착한 대향 타겟 스퍼터링(facing target sputtering: FTS) 장치를 사용하여 AZO 박막을 제작한다. 기존의 여러 증착법과 달리, FTS 장치는 두 타겟 사이에 형성되는 플라즈마 내의 ${\gamma}$-전자를 구속하게 되며, 낮은 가스 압력에서 고밀도 플라즈마가 생성되어 빠른 증착 속도와 안정적인 방전을 유지한 상태에서 박막을 증착할 수가 있다. 또한 기판과 플라즈마가 이격되어 있어 높은 에너지를 갖는 입자들의 기판 충돌을 억제할 수 있는 장점들을 갖는다. 이종 타겟인 ZnO와 Al2O3를 사용하고 각 타겟에 인가되는 파워 변화를 통해 AZO 박막 내 Al2O3의 성분비를 조절하였다. ZnO 타겟의 증착 파워를 100 W로 고정할 경우, Al2O3 타겟의 증착 파워가 (50~90) W으로 실험을 하였으며, Al2O3 타겟의 증착 파워가 70 W일 때 AZO 박막의 Al2O3 성분비는 2.02 wt.%이며 박막의 비저항 값은 $5{\times}10^{-4}{\Omega}{\cdot}cm$로 최소값을 보였다. 이러한 비저항의 변화는 파워에 따른 AZO 박막의 캐리어 이동도(Hall mobility)와 캐리어의 농도(Carrier Concentration)의 변화와 밀접한 관계가 있음을 보여주며, 특히 AZO 박막의 캐리어 농도와 캐리어 이동도는 AZO 박막을 형성하고 있는 결정립의 크기에 의존하는 것이 X-선 회절 패턴과 SEM으로부터 확인되었다. 특히, 본 연구에서는 두 개의 이종 타겟(hetero target) Al2O3와 ZnO를 장착하고 각각의 파워를 변화시켜 도핑 량을 조절할 수는 대향 타겟 스퍼터링(FTS: facing-target sputtering) 방법을 이용하여 제작된 AZO 박막에 대해 전기적, 광학적 및 구조적 특성을 분석하고 ITO의 대체물로서의 가능성을 검토하고자 한다.

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Structural and Electrical Properties of Fluorine-doped Zinc Tin Oxide Thin Films Prepared by Radio-Frequency Magnetron Sputtering

  • Pandey, Rina;Cho, Se Hee;Hwang, Do Kyung;Choi, Won Kook
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.335-335
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    • 2014
  • Over the past several years, transparent conducting oxides have been extensively studied in order to replace indium tin oxide (ITO). Here we report on fluorine doped zinc tin oxide (FZTO) films deposited on glass substrates by radio-frequency (RF) magnetron sputtering using a 30 wt% ZnO with 70 wt% SnO2 ceramic targets. The F-doping was carried out by introducing a mixed gas of pure Ar, CF4, and O2 forming gas into the sputtering chamber while sputtering ZTO target. Annealing temperature affects the structural, electrical and optical properties of FZTO thin films. All the as-deposited FZTO films grown at room temperature are found to be amorphous because of the immiscibility of SnO2 and ZnO. Even after the as-deposited FZTO films were annealed from $300{\sim}500^{\circ}C$, there were no significant changes. However, when the sample is annealed temperature up to $600^{\circ}C$, two distinct diffraction peaks appear in XRD spectra at $2{\Theta}=34.0^{\circ}$ and $52.02^{\circ}$, respectively, which correspond to the (101) and (211) planes of rutile phase SnO2. FZTO thin film annealed at $600^{\circ}C$ resulted in decrease of resistivity $5.47{\times}10^{-3}{\Omega}cm$, carrier concentration ~1019 cm-3, mobility~20 cm2 V-1s-1 and increase of optical band gap from 3.41 to 3.60 eV with increasing the annealing temperatures and well explained by Burstein-Moss effect. Change of work function with the annealing temperature was obtained by ultraviolet photoemission spectroscopy. The increase of annealing temperature leads to increase of work function from ${\phi}=3.80eV$ (as-deposited FZTO) to ${\phi}=4.10eV$ ($600^{\circ}C$ annealed FZTO) which are quite smaller than 4.62 eV for Al-ZnO and 4.74 eV for SnO2. Through X-ray photoelectron spectroscopy, incorporation of F atoms was found at around the binding energy of 684.28 eV in the as-deposited and annealed FZTO up to 400oC, but can't be observed in the annealed FZTO at 500oC. This result indicates that F atoms in FZTO films are loosely bound or probably located in the interstitial sites instead of substitutional sites and thus easily diffused into the vacuum from the films by thermal annealing. The optical transmittance of FZTO films was higher than 80% in all specimens and 2-3% higher than ZTO films. FZTO is a possible potential transparent conducting oxide (TCO) alternative for application in optoelectronics.

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PEO법으로 (Si,Mn)-HA 코팅된 치과 임플란트용 Ti 합금의 생체적합성 및 표면특성 (Biocompatibility and Surface Characteristics of (Si,Mn)-HA Coated Ti-Alloy by Plasma Electrolytic Oxidation)

  • 강정인;손미경;최한철
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2017년도 춘계학술대회 논문집
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    • pp.83-83
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    • 2017
  • 생체재료의 표면은 이식과 동시에 생체계면의 역할을 하게 되어, 일련의 생물학적 반응이 시작되고 진행되는 중요한 장소가 된다. 초기에 생체계면에서 일어나는 단백질 흡착이나 염증반응을 비롯한 생물학적 반응들은 궁극적으로 임플란트의 성패를 좌우할 만큼 중요하다. 골융합을 개선하기 위한 다른 방법으로 생체불활성의 타이타늄 (Ti)과 골조직의 능동적인 반응을 이루기 위해 생체활성 표면을 부여함으로서 계면에서의 골형성 반응을 증진시키는 방법이 이용된다. 생체불활성의 Ti과 Ti합금은 골조직과 직접적인 결합을 이루지 못하므로, 골조직과의 반응을 향상하기 위해 여러 종류의 생체활성 재료를 코팅하는 방법이 연구되어 왔고, 이 중 생체의 변화와 가장 유사한 하이드록시아파타이트 코팅이 가장 대중적인 방법으로 사용되었으며 이는 초기 골형성을 촉진하는 것으로 알려졌다. 치과용 임플란트의 표면형상과 화학조성이 골 융합에 영향을 미치는 가장 중요한 인자이므로 최근의 연구동향은 이들 두 가지 표면특성을 결합함으로서 결과적으로 최적의 골세포반응을 유도하고, 골융합 후 골조직과의 micromechanical interlocking에 의해 임플란트의 안정성에 중요한 역할을 하는 마이크론 단위의 표면조도와 표면 구조를 유지하면서, 부가적으로 골 조직 반응을 능동적으로 개선할 수 있는 생체활성 성분을 부여하여 골 융합에 상승효과를 이루기 위한 표면처리법에 관해 많은 연구가 요구되어지고 있다. 따라서 골을 구하는 원소인 망간과 실리콘으로 치환된 하이드록시아파타이트를 플라즈마 전해 산화법으로 코팅하여 세포와 잘 결합할 수 있는 표면을 제공함으로써 골 융합과 치유기간을 단축시킬 수 있을 것으로 사료된다. 실험방법은 시편은 치과 임플란트 제작 합금인 Ti-6Al-4V ELI disk (grade 5, Timet Co., USA; diameter, 10 mm, thickness, 3 mm)이며, calcium acetate monohydrate, calcium glycerophosphate, manganese(II) acetate tetrahydrate, sodium metasilicate을 설계조건에 따라 혼합 제조된 전해질 용액을 이용하여 플라즈마 전해 산화법으로 표면 코팅을 실시하였다. 각 시편의 플라즈마 전해시 전압은 280V로 인가하였고, 전류밀도는 70mA로 정전류를 공급하여 해당 인가전압 도달 후 3분 동안 정전압 방식을 유지하였다. 코팅된 피막 표면을 주사전자현미경과 X-선 회절분석을 통하여 미세구조 및 결정상을 관찰하였다. 또한 코팅된 표면의 생체활성 평가는 정량적으로 평가하기 위해 동전위시험과 AC 임피던스를 통하여 시행하였다. 분극거동을 확인하기 위해 potentiostat (Model PARSTAT 2273, EG&G, USA)을 이용하여 구강 내 환경과 유사한 $36.5{\pm}1^{\circ}C$의 0.9 wt.% NaCl에서 실시하였다. 전기화학적 부식 거동은 potentiodynamic 방법으로 조사하였고 인가전위는 -1500 mV에서 2000 mV까지 분당 1.67 mV/min 의 주사속도로 인가하여 시험을 수행하였다. 임피던스 측정은 potentiostat (Model PARSTAT 2273, EG&G, USA)을 이용하였으며, 측정에 사용한 주파수 영역은 10mHz ~ 100kHz 까지의 범위로 하여 조사하였고 ZSimWin(Princeton applied Research, USA) 소프트웨어를 사용하여 용액의 저항, 분극 저항 값을 산출하였다. 망간의 함량이 증가할수록 불규칙한 기공을 보였으며, 실리콘은 $TiO_2$ 산화막 형성을 저해하는 경향을 확인할 수 있었다. 단독으로 표면을 처리한 경우보다 두 가지 원소를 이용해 복합 표면처리를 시행한 경우가 내식성이 좋아 임플란트과의 골 유착에 긍정적인 영향을 미칠 것으로 사료된다.

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야구 선수 주관절의 통증과 골 변화에 대한 유병률 조사 (A Study for Prevalence of Pain and Bony Changes of the Elbow in Baseball Players)

  • 임채준;김성택;김창윤;안기용;박진범;윤태현
    • 대한정형외과스포츠의학회지
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    • 제6권1호
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    • pp.50-56
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    • 2007
  • 목적: 소년부터 성인까지의 야구 선수들의 주관절 손상의 빈도와 발생 양상 및 추이를 알아보고자 하였다. 대상 및 방법: 2004년 1월부터 12월까지 초등학교, 중학교, 고등학교 그리고 프로 야구 선수 각각 80명, 총 320명을 대상으로 설문 조사 및 양측 주관절의 전 후면과 측면 단순 방사선 촬영을 시행하였다. 결과: 모든 선수 군에서 주관절의 통증 부위와 골 변화가 내측에서 가장 많았으며 특히 내측 상과 골단 비후(Hypertrophy of medial epicondyle)가 많았다. 선수의 연령이 증가할수록 주관절의 방사선학적 변화가 증가하였으며 초등학교 선수 65%, 중학교 선수 82%, 고등학교 선수 85%, 프로 선수 88%에서 주관절의 골 변화가 나타났다. 결론: 야구 선수들의 주관절 골 변화는 연령이 증가할수록 많았으며 과거에 비해 증가하였다.

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