• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2002년도 추계학술강연 및 발표대회
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• pp.29-29
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• 2002

공구강 등 산업용 재료로 널리 사용되는 카바이드 계 재료는 입자 크기 및 분포에 따라 기계적 성질이 변화하므로, 이를 제어하고 조절하는 기술에 관하여 많은 연구가 진행되어 왔다. 본 연구에서는 TiCN-WC-Co 복합초경계 에서 소결 공정 및 조성변화에 따른 입자 모양을 관찰하고 이에 따른 업자 성장 거동을 고찰하였다. 일반적으로 입자 조대화 양상과 고상 입자의 모양과는 밀접한 관계가 있다. 각진 입자의 경우에 는 계면이 원자적으로 singular 하여 원자의 홉착이 어렵기 때문에 임계값 이상의 성장 구동력을 받 는 몇몇 입자만 성장하는 비정상 입자 성장이 일어날 수 있다. 반면에 계면이 rough한 퉁큰 엽자의 경우에는 원자 홉착에 필요한 구동력이 존재하지 않아 성장 구동력을 받는 모든 입자들이 성장하기 때문에 정상 입자 성장을 하게 된다. 이와 같이 입자 모양에 따른 입자 성장 거동은 전체 미세구조를 결정하게 되며, 이에 따른 물리 화학적 물성을 변화시킨다. 이러한 입자 성장 원리를 적용하 면 복합초경계 (TiCN-WC-Co)에서도 입자성장이 억제되고 치밀한 소결체를 제조할 수 있을 것이다. 본 실험에서는 평균입도가 각각 0.1, 1.33, 2$\mu\textrm{m}$인 TiCN, WC, Co 분말을 사용하여 $((I00_{-x)}TiCN+_xWC)-30Co$ (wt%) 조성에서 TiCN/WC 비를 변화시키면서 업자 모양과 입자성장 거동을 관찰하였다. 청량된 분말은 WC 초경 볼로 밀렁하고, 건조한 후, 100 mesh 체로 조립화 하였다. 이 분말을 100 MPa의 압력으로 냉간정수압성형 하고 $10^{-2}$ torr의 진공분위기의 graphite f furnace에서 carbon black으로 packing 하여 액상형성 온도 이상에서 소결하였다. 소결된 시편은 경면 연마하여 주사전자현미경으로 미세 조직을 관찰하였다. TiCN-30Co 조성 시편은 corner-round 모양의 입자 모양으로 소결 시간 증가에 따라 빠른 입자 성장을 나타내었다 .(7STiCN+2SWC)-30Co 조성 시변의 경우 일반적으로 보고된 바와 같이 core/shell 구조를 나타내었으며, core는 TiC-rich 상이었고, shell은 (Ti,W)(C,N) 복합 탄화물 상이었다. WC 함량이 중가함에 따라 입자의 corner-round 영역이 증가하였으며 (SOTiCN-SOWC)-30Co 조성 근처에서는 거의 둥근 형태의 입자 모양을 나타내었다. 또한 TiCN - 30Co 조성 시편에 비하여 WC가 첨가된 시펀들은 작은 평균입자크기를 나타내었다. 본 연구의 결과는 shell 영역 조성 변화는 계면에너지 이방성과 기지상 내의 펑형 입자 모양을 변화시키고 나아가 입자 성장 속도 에도 영향을 미친다는 것을 보여준다.

• Imaging Science in Dentistry
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• 제40권2호
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• pp.69-74
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• 2010

Purpose : The research was performed to predict the three dimensional relationship between the impacted mesiodens and the maxillary central incisors and the proximity with the anatomic structures by comparing their panoramic images with the CT images. Materials and Methods : Among the patients visiting Seoul National University Dental Hospital from April 2003 to July 2007, those with mesiodens were selected (154 mesiodens of 120 patients). The numbers, shapes, orientation and positional relationship of mesiodens with maxillary central incisors were investigated in the panoramic images. The proximity with the anatomical structures and complications were investigated in the CT images as well. Results : The sex ratio (M : F) was 2.28 : 1 and the mean number of mesiodens per one patient was 1.28. Conical shape was 84.4% and inverted orientation was 51.9%. There were more cases of anatomical structures encroachment, especially on the nasal floor and nasopalatine duct, when the mesiodens was not superimposed with the central incisor. There were, however, many cases of the nasopalatine duct encroachment when the mesiodens was superimpoised with the apical 1/3 of central incisor (52.6%). Delayed eruption (55.6%), crown rotation (66.7%) and crown resorption (100%) were observed when the mesiodens was superimposed with the crown of the central incisor. Conclusion : It is possible to predict three dimensional relationship between the impacted mesiodens and the maxillary central incisors in the panoramic images, but more details should be confirmed by the CT images when necessary.

• Journal of Gastric Cancer
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• 제7권1호
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• pp.47-54
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• 2007

목적: 대한위암학회 정보전산위원회는 국내 위암의 임상병리학적 양상과 치료 방법에 대한 시대적 변화를 파악하고자 2004년에 위암으로 수술받은 환자들에 대하여 전국조사를 실시하였다. 대상 및 방법: 2004년에 위암으로 수술받은 환자들의 자료를 57개 병원으로부터 수집하였으며, 2002년에 보고되었던 1995년과 1999년의 자료와 비교하였다. 14개 항목(성별, 나이, 위암의 위치와 크기, 육안형, 접근방법, 근치도, 수술종류, 재건술, 국제보건기구 분류 및 Lauren 분류, UICC 병기분류, 전이 및 절제림프절 개수)이 분석되었다. 연중 시행하는 위암수술 규모에 따라 57개 병원을 네 군(1군, <100; 2군, ${\geq}100$ 및 <200; 3군, ${\geq}200$ 및 <500; 4군, ${\geq}500$)으로 나누어 임상항목들을 군간에 비교하였다. 결과: 2004년에 위암으로 수술받은 환자들 11,293명의 자료가 57개 병원으로부터 수집되었다. 남녀비는 2.05:1(7,586/3,705)이었고, 평균 연령은 58.0세였다. 호발연령분포에 있어서 남녀 모두 최근으로 올수록 증가하는 양상을 보였다. 조기위암의 비율은 2004년에 47.4%로 1995년의 28.6%, 1999년의 32.8%에 비해 증가하였다. 절제림프절의 평균개수는 34.0개(1군 32.8개, 2군 34.0개, 3군 36.1개, 4군 32.9개)였다. 결론: 조기위암이 1995년과 1999년에 비해 2004년에 증가하였다. 절제림프절 개수로 볼 때 위암 수술은 병원규모에 무관하게 적정 림프절 절제를 동반한 수술이 이루어지고 있었다. 향후 이 보고가 위암의 진료 및 연구의 참고자료로 활용되기를 기대한다.

• Bulletin of the Korean Chemical Society
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• 제28권2호
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• pp.251-256
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• 2007

The crystal structure of fully dehydrated partially Cs+-exchanged zeolite X, [Cs52Na40Si100Al92O384], a = 24.9765(10) A, has been determined by single-crystal X-ray diffraction techniques in the cubic space group Fd3 at 21 °C. The crystal was prepared by flow method for 5 days using exchange solution in which mole ratio of CsOH and CsNO3 was 1 : 1 with total concentration of 0.05 M. The crystal was then dehydrated at 400 °C and 2 × 10-6 Torr for 2 days. The structure was refined to the final error indices, R1 = 0.051 and wR2 (based on F2) = 0.094 with 247 reflections for which Fo > 4σ (Fo). In this structure, about fifty-two Cs+ ions per unit cell are located at six different crystallographic sites with special selectivity; about one Cs+ ion is located at site I, at the centers of double oxygen-rings (D6Rs), two Cs+ ions are located at site I', and six Cs+ ions are found at site II'. This is contrary to common view that Cs+ ions cannot pass sodalite cavities nor D6Rs because six-ring entrances are too small. Ring-opening by the formation of ?OH groups and ring-flexing make Cs+ ions at sites I, I', and II' enter six-oxygen rings. The defects of zeolite frameworks also give enough mobility to Cs+ ions to enter sodalite cavities and D6Rs. Another six Cs+ ions are found at site II, thirty-six are located at site III, and one is located at site III' in the supercage, respectively. Forty Na+ ions per unit cell are located at two different crystallographic sites; about fourteen are located at site I, the centers of D6Rs and twenty-six are also located at site II in the supercage. Cs+ ions and Na+ ions at site II are recessed ca. 0.34(1) A and 1.91(1) A into the supercage, respectively. In this work, the highest exchange level of Cs+ ions per unit cell was achieved in zeolite X by conventional aqueous solution methods and it was also shown that Cs+ ion could pass through the sixoxygen rings.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제14권1호
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• pp.95-102
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• 2003

목 적：본 연구는 청소년의 자살성향과 관련된 정서적 특성을 지역사회연구를 통하여 조사함과 아울러 우울불안 집단을 설정하여 그들의 충동성과 자살사고를 알아보고자 하였다. 방 법：경기도 고양시의 1909명의 중·고등학생들을 대상으로 Center for Epidemiologic Study for Depression(CES-D), Revised Children's Manifest Anxiety Scale(RCMAS), Youth Self Report(YSR)의 Anxious/Depressed subscale을 사용하여 우울불안집단을 선정하였고, 대조집단과 비교하여 PS-1 of Offer's Self Image Questionnaire(PS-1 of OSIQ), Suicide Ideation Questionnaire(SIQ) 척도점수를 측정하였다. 또한 자살사고와 관련된 정서적 요인들과의 상관성 및 자살사고 예측력을 분석하였다. 결 과：우울불안집단을 연구대상의 6.58%를 차지하였으며 남녀비는 약 1:1.5이었다. 또한 우울불안집단에서 대조집단에 비하여 충동성조절 점수는 유의하게 높았고 자살사고 척도 점수도 유의하게 높았다. 자살사고와 관련하여 우울척도, 불안척도, 우울-불안척도 및 자살사고 척도는 모두 유의한 상관성을 보인 요인들이었으며, 다중회귀분석 결과 우울과 불안이 자살사고를 예측하는 유의한 요인이었다. 결 론：지역사회 청소년들을 대상으로 자살사고의 정서적 요인들 조사한 결과 우울 및 불안성향을 지닌 집단이 자살의 고위험군임을 시사하였으며, 이를 위한 예방적 개입이 중요함을 알 수 있었다.

• Tuberculosis and Respiratory Diseases
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• 제38권2호
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• pp.128-134
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• 1991

This report is an analysis of 60 cases of primary mediastinal tumors and cysts which were experienced in chonbuk National University Hospital, Wonkwang University Hospital and Chonju Presbyterian Medical Center from january 1985 to October 1990. The result was summarized like this; 1) Age distribution was various from ages of 5 to 75 years. There were 26 males and 34 females, sex ratio of patients was 1: 1.3 (M:F). 2) The most common chief compliant was dyspnea (21 cases, 35%) and followed by chest pain, coughing and chest discomfort. 17 patients (28%) were asymptomatic. 3) The most common primary mediastinal tumor was thymoma, which comprise 28% (17 cases) of all our cases and followed by neruogenic tumor (14 cases, 23%) and germ cell tumor (11 cases, 18%). 4) The incidence of malignancy of all case was 22%; 2 cases were asymptomatic and the most common malignancy was malignant lympoma (5 cases, 38.5%). 5) The anterior mediastinum was the most common tumor location and followed by posterior and middle mediastinum. Anterior mediastinal tumors mainly consisted of thymomas and germ cell tumors and posterioc mediastinal tumors mainly did neurogenic tumors. 6) Of 60 cases, 21 cases were confirmed histopathologically by percutaneous transthoracic needle lung biopsy. 7) Of 60 cases, 40 cases were received radical tumor resection.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1983년도 제17차 학술대회연제순서 및 초록
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• pp.6.3-6
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• 1983

1972년 부터 1982년 까지 전주예수병원 이비인후과에 내원한 식도 및 기도 이문환자 287 예를 분석하여, 다음과 같은 결론을 얻었다. 1) 식도이물과 기도이물의 빈도는 약 8 : 1이었다. 2) 식도이물의 종류별 빈도는 주화가 55.8%로 가장 많았고, 다음이 골편이었다(28.5 %). 기도이물의 종류별 빈도는 콩종류(39.4%)가 가장 많았고, 금속류, 플라스틱조각 순이었다. 3) 식도 이물은 남자가 53.1 % 여자가 46.9%로 별 차이가 없었으며, 기도이물에서는 약간 남자가 많았다 (57.9 % ＞ 42.1 % ). 4) 식도이물은 5세 이하가 61.8 %로 가장 많았으며, 40세 이상에서도 25.7 %를 차지하였다. 5) 식도이물의 개재부위는 제1협착부에서 82.3 %로 가장 많았다. 기도이물에서는 우측기관지가 44.7% 좌측기관지가 23.8 %로 우측에서 많았다. 6) 식도이물 개재기간은 1 일이내 가 62.2 % 였고 기도이물에서는 1 일이내가 55.2 %였다. 7) 기도이물의 합병증으로는 폐염이 55.5%로 가장 많았다. 8) 기도이물의 치료 방법으로는 ventilation-bron-choscopy가 84.3 %로 가장 많았고 2예에서 사망 하였다.

• 대한핵의학회지
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• 제16권1호
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• pp.41-48
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• 1982

113 patients with nodular goiter were studied cytologically by needle aspiration for differential diagnosis at the department of internal medicine, Chung Nam National University Hospital since October 1980 till July 1981, and the final diagnosis taken from biopsies were compared with the cytologic method on the 44 cases who received operation. The results were obtained as follows: 1. Among the 113 cases of total patients, male were 15 cases (13.3%) and female were 98 cases (86.7%) and the sex ratio (M:F) was 1 : 6.5. The peak age incidence was in the third decade followed by forth and second decades. 2. The findings of cytological diagnosis in 113 cases showed benign adenoma in 69 cases (61.1 %), Subacute and chronic thyroiditis in 22 cases(19.5%), papillary carcinoma in 15 cases (13.3%) and follicular carcinoma in 7 cases (6.2%), respectively, and 48 cases (69.6%) of the.adenomas and 2 cases(9.1%) of papillary carcinomas showed combined cystic degeneration of the nodules. 3. The diameter of the nodules by palpation revealed within $2\sim5cm$ in 88 cases (77.9%) out of 113 cases, below 2 cm in 17 cases and over 5cm in 8 cases and there were no significant relationship between the size of the nodule and disease entity. 4. The findings of thyroid scintigram using $^{131}I$ in 113 cases of nodular goiter showed "cold nodule" in 111 cases (98.2%) and normal scan (radioactivity) in 2 cases (1.8%) which showed adenoma in cytology and there was no cases with "hot nodule". 5. The thyroid functions of the 113 cases revealed as euthyroidism in 108 cases (95. 6%), hypothyroidism in 2 cases (1.8%) who showed chronic thyroiditis and hyperthyroidism in 3 cases (2.7%) in adenomas but there was no evidence that the nodules of the above 3 cases were the reason of hyperthyroidism. 6. In 44 operated cases, the histological diagnosis revealed 23 cases of adenoma out of 27 cases(85.2%) who were diagnosed as adenoma by cytology and 15 cases of malignancy out of 17 cases (88.2 %), and the overall diagnostic accuracy of aspiration cytology was 86.4 %.

• Asian-Australasian Journal of Animal Sciences
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• 제32권12호
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• pp.1897-1906
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• 2019

Objective: An experiment was conducted to investigate the effects of dietary non-phytate phosphorus (nPP) deficiency on intestinal pH value, digestive enzyme activity, morphology, nutrient utilization, and gene expression of NaPi-IIb in meat ducks from 1 to 21 d of age. Methods: A total of 525 one-d-old Cherry Valley ducklings were fed diets (with 7 pens of 15 ducklings, or 105 total ducklings, on each diet) with five levels of nPP (0.22%, 0.34%, 0.40%, 0.46%, or 0.58%) for 21 d in a completely randomized design. Five experimental diets contained a constant calcium (Ca) content of approximately 0.9%. Body weight (BW), body weight gain (BWG), feed intake (FI), and feed to gain ratio (F:G) were measured at 14 and 21 d of age. Ducks were sampled for duodenum and jejunum digestion and absorption function on 14 and 21 d. Nutrient utilization was assessed using 25- to 27-d-old ducks. Results: The results showed ducks fed 0.22% nPP had lower (p<0.05) growth performance and nutrient utilization and higher (p<0.05) serum Ca content and alkaline phosphatase (ALP) activity. When dietary nPP levels were increased, BW (d 14 and 21), BWG and FI (all intervals), and the serum phosphorus (P) content linearly and quadratically increased (p<0.05); and the jejunal pH value (d 14), duodenal muscle layer thickness (d 14), excreta dry matter, crude protein, energy, Ca and total P utilization linearly increased (p<0.05); however, the serum ALP activity, jejunal $Na^+-K^+$-ATPase activity, and duodenal NaPi-IIb mRNA level (d 21) linearly decreased (p<0.05). Conclusion: The results indicated that ducks aged from 1 to 21 d fed diets with 0.22% nPP had poor growth performance related to poor intestinal digestion and absorption ability; but when fed diets with 0.40%, 0.46%, and 0.58% nPP, ducks presented a better growth performance, intestinal digestion and absorption function.

• Clinical and Experimental Pediatrics
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• 제64권9호
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• pp.480-488
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• 2021

Background: An adequate large-scale pediatric cohort based on nationwide administrative data is lacking in Korea. Purpose: This study established the National Investigation of Birth Cohort in Korea study 2008 (NICKs-2008) based on data from a nationwide population-based health screening program and data on healthcare utilization for children. Methods: The NICKs-2008 study consisted of the Korean National Health Insurance System (NHIS) and the National Health Screening Program for Infants and Children (NHSPIC) databases comprising children born in 2008 (n=469,248) and 2009 (n=448,459) in the Republic of Korea. The NHIS database contains data on age, sex, residential area, income, healthcare utilization (International Classification of Diseases10 codes, procedure codes, and drug classification codes), and healthcare providers. The NHSPIC consists of 7 screening rounds. These screening sessions comprised physical examination, developmental screening (rounds 2-7), a general health questionnaire, and age-specific anticipatory guidance. Results: During the 10-year follow-up, 2,718 children (0.3%) died, including more boys than girls (hazard ratio, 1.145; P<0.001). A total of 848,048 children participated in at least 1 of the 7 rounds of the NHSPIC, while 96,046 participated in all 7 screening programs. A total of 823 infants (0.1%) weighed less than 1,000 g, 3,177 (0.4%) weighed 1,000-1,499 g, 37,166 (4.4%) weighed 1,500-2,499 g, 773,081 (91.4%) weighed 2,500-4,000 g, and 32,016 (5.1%) weighed over 4,000 g. There were 23,404 premature babies (5.5%) in 2008 compared to 23,368 (5.6%) in 2009. The developmental screening test indicated appropriate development in 95%-98% of children, follow-up requirements for 1%-4% of children, and recommendations for further evaluation for 1% of children. Conclusion: The NICKs-2008, which integrates data from the NHIS and NHSPIC databases, can be used to analyze disease onset prior to hospitalization based on information such as lifestyle, eating habits, and risk factors.