• Computers and Concrete
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• 제33권4호
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• pp.399-407
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• 2024

This study nondestructively examined the evolution of crack density in ultra-high performance concrete (UHPC) upon cyclic loading. Uniaxial compression was repeatedly applied to the cylindrical specimens at levels corresponding to 32% and 53% of the maximum load-bearing capacity, each at a steady strain rate. At each stage, both P-wave and S-wave velocities were measured in the absence of the applied load. In particular, the continuous monitoring of P-wave velocity from the first loading prior to the second loading allowed real-time observation of the strengthening effect during loading and the recovery effect afterwards. Increasing the number of cycles resulted in the reduction of both elastic wave velocities and Young's modulus, along with a slight rise in Poisson's ratio in both tested cases. The computed crack density showed a monotonically increasing trend with repeated loading, more significant at 53% than at 32% loading. Furthermore, the spatial distribution of the crack density along the height was achieved, validating the directional dependency of microcracking development. This study demonstrated the capability of the crack density to capture the evolution of microcracks in UHPC under cyclic loading condition, as an early-stage damage indicator.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 춘계학술대회
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• pp.99-99
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• 2020

참당귀(Angelica gigas Nakai)는 중국의 동북부지역, 일본 및 한반도 전역에 자생하고 있으며, 예로부터 보혈, 활혈지통, 윤장등의 효능으로 심신혈허, 월경불순, 통경경폐 등의 병증에 주로 사용되었고, 8월부터 뿌리가 급격히 비대하여 10월 말에서 11월 초에 수확을 한다. 본 연구는 참당귀의 주산지인 봉화, 평창을 비롯한 영양, 인제 등 4지역을 선정하여 미세기상장비를 설치 및 토양의 이화학성 분석을 통해 지역별 생육환경을 측정하였고, 또한 참당귀의 생육특성을 조사하였다. 그 결과 5월에서 10월까지 평균 대기온도와 일사량은 인제지역에서 다른지역에 비해 비교적 높은 경향을 나타냈다. 또한 토양온도는 5월에서 8월까지는 영양지역이, 9월과 10월은 봉화지역이 다른지역에 비해 비교적 높은 것으로 조사되었다. 지역별 토양 성분의 이화학적 특성은 봉화지역이 유기물(5.17%), 전질소(0.19%), 유효인산(2187.76mg/kg), 칼륨(1.53cmol⁺/kg)의 함량이 다른 지역에 비해 높은 경향으로 확인되었고, 인제지역이 칼슘(12.63 cmol⁺/kg), 마그네슘(3.7cmol⁺/kg)등 미량원소의 함량이 높은 것으로 분석되었다. pH는 지역별 차이가 확인되지 않았으며, 영양지역의 토성이 사질식양토로 배수성의 차이는 확인되었다. 이에 따른 참당귀의 생육특성은 초장과 줄기직경은 영양지역에서 각각 70.95cm와 35.72mm로 가장 높게 측정되었으며, 잎 길이및 너비는 평창지역에서 각각 42.84cm, 52.39cm로 가장 높게 측정되었다. 뿌리직경은 영양에서 50.49mm, 뿌리길이는 봉화에서 38.05cm, 생중량은 평창에서 328.23g으로 다른지역에 비해 높은 경향을 나타냈다. 상기 결과를 바탕 재배환경과 생장량간의 상관관계를 분석하였다. 재배환경 중 대기 및 토양온도, 대기 습도는 실험이 수행되어진 전 지역에서 이상고온이나 저온과 같은 특이점 없이 비슷한 양상으로 측정되었고, 이에 따라 참당귀생장에 대해 유의한 상관관계가 분석되지 않았다. 토양습도는 지상부(초장, 줄기직경, 잎길이, 잎너비)의 생육과 음의 상관관계에 있다고 사료되나 유의성이 검증되지 않았다.

• Journal of Photoscience
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• 제9권2호
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• pp.488-490
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• 2002

DNA photodamage mediated by photosensitizers are believed to play an important role in solar UVA carcinogenesis. We investigated the relationship between the DNA-damaging abilities of photoexcited xanthone analogues (as photosensitizers) and their highest occupied molecular orbital (HOMO) energies. DNA damage was examined using /sup 32/P-labeled DNA fragments obtained from the p53 tumor suppressor gene. These compounds induced DNA photodamage in a similar manner, and the extents of DNA damage were following order: xanthone> thioxanthone > acridone. Photoexcited xanthone caused nucleobase oxidation specifically at 5'-G of GG sequence in double-stranded DNA. An oxidative product of 2'-deoxyguanosine, 8-hydroxy-2'-deoxyguanosine (8-OHdG), was detected, and the amount was decreased by DNA denaturation. These findings suggest that photoexcited xanthone generates 8-OHdG at 5'-G of GG in double-stranded DNA through electron transfer. The calculated HOMO energies of these photosensitizers decreased in the following order: xanthone> thioxanthone > acridone. This study has demonstrated that DNA-damaging abilities of these photosensitizers increased exponentially with an increase in their HOMO energies.

• 대한한의학회지
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• 제25권4호
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• pp.79-89
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• 2004

Saussurea lappa and Taraxacum mongolicum have been used for herbal medicinal treatments against cancers in East Asia. We performed this study to understand the molecular basis underlying the anti-tumor effects of two herbs and analyzed the effects of these medicinal herbs on proliferation and on expression of cell growth/apoptosis related molecules by using an AGS gastric cancer cell line. The treatments of Saussurea lappa dramatically reduced cell viabilities in a dose and time-dependent manner, but Taraxacum mongolicum did not. FACS analysis and Annexin V staining assay also showed that Saussurea lappa induces apoptotic cell death of AGS. Expression analyses via RT-PCR and Western blots revealed that Saussurea lappa increased expression of the p53 and its downstream effector p21/sup Waf1/, and that the both increased expression of apoptosis related Bax and cleavage of active caspase-3 protein. We also confirmed the translocation of Bax to mitochondria Collectively, our data demonstrate that Saussurea lappa induces growth inhibition and apoptosis of human gastric cancer cells, and these effects are correlated with down- and up-regulation of growth-regulating apoptotic and tumor suppressor genes, respectively.

• 대한수의학회지
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• 제45권4호
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• pp.457-464
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• 2005

The irradiation of radioactive ${\gamma}-ray$ induces apoptosis of radiosensitive organs for homeostasis. In this study, we investigated the repair mechanisms for homeostasis in the small intestine after cell damage by $^{60}Co\;{\gamma}-ray$ irradiation. The apoptosis was most frequently observed in the crypt cells of the small intestine after four and six hours by radioactive ${\gamma}-ray$ irradiation, and the frequency of apoptosis was proportional to the amount of irradiation. Also, the number of apoptotic cells was coincident with expression pattern of p53. Interestingly, PCNA (proliferating cell nuclear antigen) which is engaged in DNA replication and repair was expressed in apoptotic cells of small intestinal crypts. Also, it was observed that cell-cycle regulator p21 which is known to induce cell-cycle arrest is co-expressed in the same apoptotic cells of irradiated small intestinal crypt cells. These findings suggest that the co-expression of PCNA and p21 proteins, which may lead to resistance to DNA damage through cell-cycle arrest is closely associated with repair of damaged gastrointestinal cells after ${\gamma}-ray$ irradiation.

• Radiation Oncology Journal
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• 제35권4호
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• pp.306-316
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• 2017

Purpose: To investigate the predictive role of maximum standardized uptake value ($SUV_{max}$) of 2-[$^{18}F$]fluoro-2-deoxy-D-glucose($^{18}F-FDG$) positron emission tomography/computed tomography (PET/CT) in nasopharyngeal cancer patients treated with intensity-modulated radiotherapy (IMRT). Materials and Methods: Between October 2006 and April 2016, 53 patients were treated with IMRT in two institutions and their PET/CT at the time of diagnosis was reviewed. The $SUV_{max}$ of their nasopharyngeal lesions and metastatic lymph nodes (LN) was recorded. IMRT was delivered using helical tomotherapy. All patients except for one were treated with concurrent chemoradiation therapy (CCRT). Correlations between $SUV_{max}$ and patients' survival and recurrence were analyzed. Results: At a median follow-up time of 31.5 months (range, 3.4 to 98.7 months), the 3-year overall survival (OS) and disease-free survival (DFS) rates were 83.2% and 77.5%, respectively. In univariate analysis, patients with a higher nodal pre-treatment $SUV_{max}$ (${\geq}13.4$) demonstrated significantly lower 3-year OS (93.1% vs. 55.5%; p = 0.003), DFS (92.7% vs. 38.5%; p < 0.001), locoregional recurrence-free survival (100% vs. 50.5%; p < 0.001), and distant metastasis-free survival (100% vs. 69.2%; p = 0.004), respectively. In multivariate analysis, high pre-treatment nodal $SUV_{max}$ (${\geq}13.4$) was a negative prognostic factor for OS (hazard ratio [HR], 7.799; 95% confidence interval [CI], 1.506-40.397; p = 0.014) and DFS (HR, 9.392; 95% CI, 1.989-44.339; p = 0.005). Conclusions: High pre-treatment nodal $SUV_{max}$ was an independent prognosticator of survival and disease progression in nasopharyngeal carcinoma patients treated with IMRT in our cohort. Therefore, nodal $SUV_{max}$ may provide important information for identifying patients who require more aggressive treatment.

• Journal of Nutrition and Health
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• 제53권5호
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• pp.488-502
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• 2020

본 연구는 광주지역 산업체 근로자 738명을 대상으로 NQ-A를 측정하여 영양상태 및 식사의 질 수준을 파악하고 이에 관련된 요인을 확인하였다. 본 연구 대상자는 교대 근무자 496명, 비교대 근무자 242명으로 구성되었다. 근무 기간은 10년 이상이 64.9%, 남성 근로자가 81%, 연령대는 50대 이상이 31.6%를 차지하였다. 교육 수준은 대학 졸업 이상이 57.2%, 월평균 가계소득은 401-600만원인 경우가 48.2%로 가장 높은 비율이었고, 가구 구성은 결혼의 여부에 따라 가족과 함께인 가구가 75.9%였다. 대상자들의 근무 형태에 따라 교대 근무와 비교대 근무자로 나누어 분석한 결과 NQ-A와 영역별 점수는 비교대 근무자가 유의하게 높았다. 연구 대상자의 NQ-A 평균 점수는 45.3점이었고, 모니터링 필요 집단은 교대 근무자에서 91.3%로 유의하게 높았다. 연구 대상자의 영양지수에 영향을 미치는 요인은 근무형태, 성별, 연령, 교육 수준, 월평균 가계 소득, 가구 구성으로 나타났다. 비교대 근무자, 여성, 가족과 함께인 가구, 50대 이상, 월평균 가계 소득 600만원 이상의 경우가 NQ-A를 높이는 요인으로 확인되었다. 연구 대상자의 균형, 다양, 절제, 식행동 영역에 영향을 미치는 요인에 대한 확인 결과, 근무 형태는 균형, 다양, 절제 영역에 공통적으로 가장 큰 영향을 미치는 요인이었고, 성별은 식행동 영역에 가장 큰 영향을 미치는 것으로 조사되었다. 본 연구는 NQ-A 지수를 활용하여 일반 산업체 근로자의 영양상태와 관련 요인 균형, 다양, 절제, 식행동으로 나누어 세부적으로 평가하고 영양지수에 영향을 미치는 요인을 파악하여 구체적으로 식생활교육 프로그램의 방향을 제시했다는데 의미가 있으며, 산업보건에서 영양관리의 필요성 및 근무 형태와 성별에 따른 차별화된 관리와 지원이 필요함을 시사한다. 즉, 근무 형태와 성별에 따른 영양관리와 식생활 교육 프로그램 마련이 요구되며, 근로자가 육체적 정신적으로 건강한 생활을 영위하는 데 가치를 두고 식습관에 관심을 가질 수 있도록 하는 교육이 이루어져야 할 것이다.

• Clinical and Experimental Pediatrics
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• 제53권1호
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• pp.33-40
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• 2010

목 적 : 조산아에서 출생 직후 말초 혈액의 C-반응성 단백(C-reactive protein, CRP) 농도가 자궁 내 염증의 침범 부위 또는 진행 정도에 따라 어떻게 달라지는 지 알아봄으로써 출생 직후 말초 혈액 CRP 측정의 임상적 의의와 유용성에 대해 연구하고자 하였다. 방 법 : 2005년 9월부터 2009년 4월까지 동국대학교 일산병원에서 출생하여 신생아 중환자실에 입원한 재태기간 32주 미만의 조산아 187명을 연구 대상으로 했다. 연구 대상을 'no histologic chorioamnionitis' [HCAM (-), 85명]군과 'histologic chorioamnionitis' [HCAM (+), 102명]군으로, 다시 HCAM (+)군을 'funisitis' [F (+), 49명]군과 'no funisitis' [F (-), 53명]군 및 'funisitis/amnonitis' [FA (+), 58명]군과 'isolated chorio-deciduitis' [FA (-), 44명]군으로 분류하였다. 출생 직후 말초 혈액의 high sensitivity CRP 농도를 측정하여 각 군 간에 비교하였다. 결 과 : HCAM (+)군, F (+)군, F (-)군, FA (+)군의 말초 혈액 CRP 농도는 모두 HCAM (-)군에 비해 높았으나(평균=0.29 vs. 0.06 mg/dL; 0.52 vs. 0.06; 0.07 vs. 0.06 mg/dL; 0.46 vs. 0.06 mg/dL, P<0.05), FA (-)군의 경우는 HCAM (-)군과 유의한 차이가 없었다. 또한, F (+)군과 FA (+)군의 말초 혈액 CRP 농도는 각각 F (-)군 및 FA (-)군보다 높았다 (평균=0.52 vs. 0.07 mg/dL; 0.46 vs. 0.05 mg/dL, P<0.05). HCAM (-)군과 F (+)군, HCAM (-)군과 FA (+)군을 감별하기 위한 경우, 말초 혈액 CRP 농도의 cut-off 값을 0.02 mg/dL으로 정하였을 때 민감도와 특이도는 모두 94% 및 53%였다(P<0.0001). 또한, F (+)군과 F (-)군, FA (+)군과 FA (-)군을 감별하기 위한 경우, 말초 혈액 CRP 농도의 cut-off 값을 0.02 mg/dL으로 정하였을 때 민감도는 각각 79%와 86%, 특이도는 모두 53%였다(P<0.002, P =0.000). 말초 혈액 CRP 농도가 0.02 mg/dL 이상인 경우, 임상적 융모양막염, 확증된 조기 발현 패혈증, 조직학적 융모양막염, 제대 혈관염의 빈도가 높았다. 결 론 : 재태기간 32주 미만의 조산아에서 출생 직후 말초 혈액 CRP 농도는 태반의 염증이 제대 혈관염이나 양막염까지 진행했을 때 유의하게 증가하여 조직학적 융모양막염의 진행 정도를 잘 반영하였고, 제대 혈관염이나 양막염의 감별 진단에 어느 정도 진단적 가치가 있을 것으로 생각된다.

• 대한수의학회지
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• 제39권3호
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• pp.593-601
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• 1999

This study was designed to evaluate the effect of cyclophosphamide(CY) on diethylnitrosamine(DEN)-induced hepatic tumors in rats. Thirty five male or female Sprague Dawley rats were continiously given water containing 0.01% DEN for 10 weeks and then were given with CY 25mg/rat/day in water for 3, 5, 7 or 9 days. The livers of rats were removed and fixed in 10% buffered neutral formalin. he appearances of positive cells by immunohistochemical methods using proliferating cell nuclear antigen (PCNA) antibody, p53 antibody and apoptotic kit were investigated. The livers of rats given with CY were grossly brilliant, red-brown color, flexible, and thin border, and stainability of the liver cells were restored microscopically, and the vaccuolated and degenerated regions were differentiated from restored regions. These restored findings also were advanced in control group because of no DEN treatment but tended to be less avanced. In immunohistochemistry, positive cells to PCNA antibody appeared more numerous in control groups than that of CY treated groups. Appearance of positive cells in CY-treated group for 7 days and for 9 days were more numerous than those of CY-treated groups for 3 days and for 5 days, respectively. So these findings suggested that CY suppressed cell proliferations and effects of these action were decreased with CY-treated days. The numbers of positive cells to PCNA antibody were more prominent in hepatocellular carcinoma regions and cholangiocarcinoma regions, and then were ranked as order of large liver cell regions and normal liver cell regions. Also the numbers of the positive cells by apoptotic kit tended to be higher in hepatocellular carcinoma regions and cholangiocarcinoma regions but not uniformly in order in all regions and were much less numbers than those of PCNA positive cells. So immunohistochemical methods using PCNA antibody together than using apoptotic kit alone when anti-carcinogen experiments. Rats with positive cells by p53 antibody were 11 of 15 rats(73.4%) in control groups and 12 of 18 rats(66.7%) in CY treated group, respectively. These positive cells appeared focally in early vacuole-occurring regions and were very low in numbers.

• Child Health Nursing Research
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• 제3권1호
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• pp.5-18
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• 1997

This study was designed to compare the educational needs of the mothers of LBW infant and normal neonate for development of the educational program. The subjects for this study were 37 mothers of LBW and 60 mothers of normal neonate at 3 general hospitals in Seoul and Inchon. The data were collected during the period from July to November, 1996. The Educational Need for Infant Care was measuerd by questionnaire that has developed by researchers. The data were analized by descriptive statistics, non-paired t-test, ANOVA, ANCOVA using SPSS PC/sup +/. The results were as fellow : 1) The educational needs of the mothers of LBW infant were higher than the mothers of normal neonate(F=14.50, P=.000). 2) There were significant associations between the educational needs of the mothers of LBW infant and delivery history(nullipara. or multipara. ) and caregiver of postpartum(t:-2.08, P=.045 ; F=3.94, P=.0282). 3) There were significant associations between the educational needs of the mothers of normal neonate and numbers of children and caregiver of postpartum(F=5.53, P=.0064 ; F=3.22, P=.0480) .4) The educational need by content was signs, symptomes and management of disorders (i. g. cyanosis, seizure, fever, vomiting etc.) were higher than general care of baby(i. g. feeding, diaper change etc.) at two groups. In conclusion, when the nurses teaching the method of infant care to mother, there sholud be in consideration of delivery history and caregiver of postpartum. Also, its educational contents must be Included of signs, symptomes and management of disorders.