• Toxicological Research
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• 제33권3호
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• pp.239-253
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• 2017

Neodymium is a future-oriented material due to its unique properties, and its use is increasing in various industrial fields worldwide. However, the toxicity caused by repeated exposure to this metal has not been studied in detail thus far. The present study was carried out to investigate the potential inhalation toxicity of nano-sized neodymium oxide ($Nd_2O_3$) following a 28-day repeated inhalation exposure in male Sprague-Dawley rats. Male rats were exposed to nano-sized $Nd_2O_3-containing$ aerosols via a nose-only inhalation system at doses of $0mg/m^3$, $0.5mg/m^3$, $2.5mg/m^3$, and $10mg/m^3$ for 6 hr/day, 5 days/week over a 28-day period, followed by a 28-day recovery period. During the experimental period, clinical signs, body weight, hematologic parameters, serum biochemical parameters, necropsy findings, organ weight, and histopathological findings were examined; neodymium distribution in the major organs and blood, bronchoalveolar lavage fluid (BALF), and oxidative stress in lung tissues were analyzed. Most of the neodymium was found to be deposited in lung tissues, showing a dose-dependent relationship. Infiltration of inflammatory cells and pulmonary alveolar proteinosis (PAP) were the main observations of lung histopathology. Infiltration of inflammatory cells was observed in the $2.5mg/m^3$ and higher dose treatment groups. PAP was observed in all treatment groups accompanied by an increase in lung weight, but was observed to a lesser extent in the $0.5mg/m^3$ treatment group. In BALF analysis, total cell counts, including macrophages and neutrophils, lactate dehydrogenase, albumin, interleukin-6, and tumor necrosis factor-alpha, increased significantly in all treatment groups. After a 4-week recovery period, these changes were generally reversed in the $0.5mg/m^3$ group, but were exacerbated in the $10mg/m^3$ group. The lowest-observed-adverse-effect concentration of nano-sized $Nd_2O_3$ was determined to be $0.5mg/m^3$, and the target organ was determined to be the lung, under the present experimental conditions in male rats.

• Korean Journal of Acupuncture
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• 제21권2호
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• pp.95-110
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• 2004

Objectives : Ulcerative colitis and Crohn's diseases are chronic inflammatory disease of the gastrointestinal tract identified mainly for diarrhea, stomachache, hemafecia. The source and pathologic mechanism about ulcerative colitis and Crohn's disease are still unknown but stress, infection, a genetic factor, environmental factors etc. may be the cause of chronic inflammatory disease of the gastrointestinal tract recently. Methods : Because ulcerative colitis and Crohn's disease is recognized as Ha-ri(下痢) or Jang-Byok(腸?) in Oriental Medicine, Rhizoma Coptidis Herbal acupunctures were injected in hapgok $(LI_4)$ which is used to treat intestinal disease in clinic. All animals were subjected to the injection of saline $(300\;{\mu}l,\;500\;{\mu}l)$ for a study control and TNBS $(300\;{\mu}l,\;500\;{\mu}l)$ into the lumen of the colon, 8cm proximal to the anus through the intestine. Rhizoma Coptidis Herbal (20 mg/ml, 0.4 ml) acupuncture solution was injected to the $LI_4$ (both hands) at the secondary injection time of TNBS in rats. And body weight, RBC count, WBC count, total protein, Paw edema rate, rate of protein leakage into CMC-pouch fluid, IgG levels and IgM levels were observed to study the effects of Rhizoma Coptidis Herbal acupuncture in hapgok $(LI_4)$. Results : In results, Rhizoma Coptidis Herbal acupuncture in hapgok $(LI_4)$ on TNBS-induced colitis reduced the rate of weight loss but had no effect on RBC and WBC count. And it reduced total protein concentration, paw edema, rate of protein leakage into CMC-pouch fluid, IgG levels and IgM levels. Conclusion : Data suggest that injection of Rhizoma Coptidis herbal acupuncture solution into hapgok has significant therapeutic effect on the colitis.

• 생명과학회지
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• 제30권2호
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• pp.191-201
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• 2020

사회의 급속한 발전과 함께 수반되는 환경오염이 인간의 건강을 위협하는 커다란 위험인자로 인식되기 시작하면서 공기오염을 억제하기 위한 노력과 공기오염에 의해 유발되는 여러 질환을 억제 및 치료하기 위한 연구개발이 급속히 증가하고 있다. 인간 건강에 나쁜 영향을 주는 공기오염의 주된 원인중의 하나인 미세먼지는 (particulate matter, PM) 크기에 따라 일반미세먼지와(PM₁₀) 초미세먼지(PM_2.5)로 나누어 질 수 있으며, 호흡기, 소화기, 및 피부에 흡수 및 부착되어 이상 면역반응을 유발하여 만성호흡기질환, 당뇨병 및 면역질환등을 촉진하는 것으로 알려져 있다. 그동안 인류의 건강을 위해 미세먼지의 발생을 억제하기 위한 범 국가적 노력과 함께 미세먼지의 유해성을 증명하기 위한 많은 연구가 진행되어 왔다. 본 총설에서는 여러 인체질환에 있어서 미세먼지가 미치는 유해성을 중심으로 소개하고 미세먼지의 생물학적 위험성을 평가하는 세포 및 동물실험법에 대해 요약하였다.

• 시큐리티연구
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• 제18호
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• pp.39-54
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• 2009

본 연구는 경호수행에서의 태권도 정신의 중요성과 의미를 규명하는데 있다. 이러한 목적을 달성하기 위하여 우선 연구대상자를 2년 이상 태권도를 지속적으로 수련해온 경호원으로 경호 수행 중의 경험을 충실히 답변할 수 있도록 평직원에서 관리자직급까지로 설정하고 유목적표집법을 이용 9명의 대상자를 표집 하였다. 이러한 연구의 과정을 통하여 도출되어진 결론은 다음과 같다. 첫째, 태권도 수련을 통하여 체득된 예의, 염치, 인내, 극기, 백절불굴의 다섯 가지 태권도정신은 경호원의 경호임무 수행에 있어서 긍정적인 영향을 미치고 있다. 경호원들은 평상시 태권도 수련 중에 요구되는 예의, 염치, 인내, 극기, 백절불굴의 정신을 태권도수련을 통하여 수양함으로써 몸과 마음으로써 태권도정신을 획득하게 된다고 진술하였다. 이렇게 체득된 태권도정신은 경호임무 수행 중에 얻게 되는 각종 스트레스와 위해상황의 발생, 조직 내의 갈등과 같은 부정적 상황을 지혜롭게 극복할 수 있는 중요기재가 되어주었다. 둘째, 일상에서 요구되는 바른 마음가짐, 정신적 건강, 유연한 사회적 태도를 함양할 수 있는 바탕을 태권도정신이 제공해준다는 신념을 가지고 있었다. 따라서 경호대상과 경호원간, 또는 상급자 경호원과 하급자 경호원간의 위계질서가 반드시 요구되는 경호경비 조직 내에서 필요로 하는 자세를 배울 수 있는 기회를 얻을 수 있었다.

• 대한지역사회영양학회지
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• 제12권3호
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• pp.259-271
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• 2007

The purpose of this study was to investigate the dietary habits and daily intake of nutrients in college students. This survey was conducted using a self-administered questionaire. The average heights and weights were 173.5 cm and 72.3 kg of male students and 161.8 cm and 57.2 kg of female students. The average of BMI was $24.2kg/m^2$ of male and $21.9kg/m^2$ of female, and the value of male students was higher than the value of female students. The response to the daily meals was 54.6% for '$2{\sim}3$ times/week'. The regularity of mealtime was 41.7% for irregular and the frequency eating after nine was 45.7% for '5-6 times/week', respectively. The repast was 72.2% for 'overeating and little eating' and was a significant difference of male and female students (p<0.05). The eating rate was higher '$10{\sim}20min$'. As for breakfast food eaten, skipping breakfast was 23.6% for 'no/week' and female students were higher than male students (p<0.05). The frequency of snacks was 36.0% for 'nothing' of males students and 34.8% for '3-4 times/week' of female students (p<0.05). The type of snack was a significant difference of males and females students (p<0.01), and was the highest 75.0% for carbonated drinks of males and 37.5% for snacks of females. The eating due to stress solution was a significant difference of male and female students (p<0.01), and was the highest 23.0% for 'frequency' of males and 44.7% for 'sometime' of females. As for food intake of male and female students, the meat intake was 66.7% for 'everything of male and female students. The fish intake was 68.1 % for '1-2times/week'. The milk, milk products, eggs and beans were each 40.3%, 58.3%, 56.9%, 47.2% for '1-2 times/week' (p<0.05). The fat intake was 55.6% for '$1{\sim}2$ times/week'. The average consumption of energy was 58% of male and 67% of female of estimated energy requirement (EER). Their mean ratio of carbohydrate: protein: fat was 57 : 15 : 28 of all subjects. The mean intakes of vitamin C and folic acid were 70% and 51% of males and 62% and 52% of females of recommended intake (RI). The mean intakes of Ca, P, Fe and Na were 71%, 140%, 146% of males and 72%, 122%, 76% of female of RI and 273% of males and 233% of females of adequate intake (AI). Therefore, nutritional education is necessary for college students to establish physicall and mentall optimal health conditions though nutritional intervention.

• 한국수정란이식학회지
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• 제6권2호
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• pp.1-17
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• 1991

It is widely recognized that the embryonic or fetal loss after breeding is common in the cattle and that it is an important factor affecting reproductive efficiency. The causes of this loss have been subject of extensive researches and the results indicate that the embryonic mortality may he primary factor responsible for low pregnancy rates in non-embryo transfer bovine populations as well as embryo transfer programs. However, it's causes are still not clearly understood. The embryonic mortality or pregnancy rate has been influenced by various embryonic and maternal effects related to genetic and environmental factors. The timing and extent of embryonic mortality vanes greatly according to authors and estimating methods, because it is difficult to make direct measurements. The major important factors that may influence the embryonic losses or pregnancy rates after embryo transfer can be summeirized. 1.When an embryo is transferred to unmated recipients, the contralateral transfer to corpus luteum results in a lower survival rate than ipsilateral deposition. When the embryos are transferred for the production of twin calves, their survivals and twin pregnancies have quite inconsistent according to the transfer methods either to the unmated-synchronized or already mated recipients and more works are needed to accurrately clarify the previous results. 2.Although embryos can be cultured in vitro some hours without the great declines in pregnancy rates, the rates differ markedly among culture times and media but may be improved by co-transfer systems. 3.Embryo developmental stages and quality grades clearly affect the survival rate following freezing and the pregnancy rate after transfer and the selection of embryos without chromosome abnormalities and of high fertile semen may also be considered to increase the pregnancy rates. 4.Many researches have attempted to relate the plasma progesterone levels to pregnancy rates and others have done either direct progesterone supplementation or luteal stimulation by hCG treatment in order to increase the pregnancy rates. However, these effects on pregnancy rates are inconsistent and also contradictory. 5.The asynchrony between donors or embryos and recipients may he a major cause of embryo death and low pregnancy rate and the sensitivity to uterine asynchyony differs in according to the quality and stages of embryos. 6.The extremes of poor or over nutrition during early pregnancy in the recipients are detrimental to the survival of embryos and the good body condition is required to prevent a reduejion of pregnancy rates. The uterine pathogens in embryonic mortality or fertility have been questioned but the infection of C.pyogenes and Campylobacter fetus is still important pathogens. 7.The heat stress during early pregnancy may reduce conceptus weight and possibly increase the embryonic mortality.

• 한국산학기술학회논문지
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• 제11권5호
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• pp.1936-1942
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• 2010

본 논문은 기능식품의 과용에 따른 간질환 환자에게 미치는 영향을 알아보기 위해, 마늘열수추출물의 용량을 달리하여, 사염화탄소에 의한 랫드의 간 손상을 유발하여 기능학적검사를 통해 간장에 미치는 용량의 중요성을 알아보았다. 실험동물은 Sprague-Dawley 종 웅성 랫드로 하여 정상군, 대조군, 양성대조군, 실험군 E1, E2, E3 군으로 나누어 각 군당 7마리씩 총 42마리를 이용하였고, 실험동물은 체중 당 사염화탄소 $0.5\;m{\ell}$ (0.20 g/kg/day)를 olive oil에 동량 희석하여 1일 1회 격일 간격으로 총 5회 복강 내 투여하여 간 손상 유발한 후 국내에서 유기농 재배한 마늘을 열수 추출하여 각 실험군에 체중 당 0.35 g/kg(E1), 0.70 g/kg(E2), 1.40 g/kg(E3)를 일일 1회, 주 5일, 4주간 위존데를 사용하여 투여하였다. 실험의 결과로 마늘추출물의 투여가 생리적 기능 활성에 긍정적인 작용을 하여 간장에서 산화스트레스를 감소시키고 독성 증감작용 및 기능학적 변화를 확인하였고, 용량에 따른 실험군(E1, E2, E3) 간의 비교에서 고농도 투여군(E3)에서는 마늘독성의 영향 때문에 E1, E2보다 긍정적인 효과를 덜 보였다.

• 한국수산과학회지
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• 제14권4호
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• pp.269-275
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• 1981

연근해 어업용 낚시 6가지형에 대하여 만능실험기로 인장속도를 290mm/min와 780mm/min로 하여 실험한 결과는 다음과 같다. 1) 낚시의 직경은 d, 미늘 기부에서 허리굽이까지의 거리를 w라 하면 낚시의 파단하중은 $B={\alpha}\;wd^2+\beta$ (단, B는 kg, w와 d는 mm)로 나타내며, 인장연도가 290mm/min 일 때의 $\alpha,\;\beta$는 둥근형 낚시 $SR_{p}-F_{1}B,\;SR_{p}-F_{1}S$는 $\alpha_{s}=0.5,\;\beta_{s}=1.6$, 모난형 낚시 $SA_{a}-F_{1}S,\;SA_{a}-F_{1}S_k,\;LA_{a}-F_{1}S_{k}$는 $\alpha_{s}=1.1,\;\beta_{s}=2.0$긴 낚시 $LA_{p}-F_{1}S$는 $\alpha_{s}=0.4,\;\beta_{s}=1.5$정도이다. 2) 인장속도가 780mm/min 일 때 윗식에서 $\alpha,\;\beta$는 둥근형 낚시는 $\alpha_{f}=0.4,\;\beta_{f}=1.4$모난형 낚시는 $\alpha_{f}=1.0$ 일본산은 $\beta_{f}=0.9$, 국산은 $\beta_{f}=-2.5$ 긴 낚시는 $\alpha_{=}0.6,\;\beta_{f}=0.4$ 정도이다. 3) 낚시의 파단변형률은 $40\sim60\%$ 정도이며, 인장속도가 빠를 때의 변형률은 느릴 때에의 $95\%$ 정도이나, 빠를 때의 파단하중은 느릴 때의 $80\%$ 정도이다. 4) 낚시가 파단되는 부위는 인장속도에 관계없이 거의 모두 허리굽이 부분이며 꼭지 기부에서 파단점까지의 거리는 낚시 길이와 거의 같다.

• 디지털융복합연구
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• 제15권1호
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• pp.227-238
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• 2017

급성 심정지는 갑작스러운 심장 기능의 상실로 인하여 수 분 안에 뇌를 비롯하여 온 몸에 혈액 공급이 되지 않아 사망으로 이어지는 대표적인 중증응급질환이다. 특히 병원 밖에서 발생하는 병원외 심정지 환자는 생존율이 매우 낮다. 그 이유는 갑작스런 발병으로 인해 주변사람들이 심정지 환자라는 것을 인식하지 못할 뿐만 아니라 인식한다 하더라도 전문 의료지식이 없어 정확한 응급조치를 취하는 것이 어렵기 때문이다. 기존의 심정지 관련 연구는 대부분 심정지 발생 후의 치료법 방안에 집중되어 있었으나, 이는 근본적인 문제해결이 어려워 생존율을 높이는데 한계가 있었다. 이러한 문제를 해결하기 위해 본 논문에서는 널리 보급된 스마트폰을 활용하여 급성 심정지 환자를 위한 알림, 사전예방, 응급조치 등의 기능을 갖춘 솔루션을 개발하였다. 이 솔루션을 활용하면 급성 심정지를 사전에 예방할 수 있고, 설사 발병한다고 하더라도 주변사람에게 신속하게 알려 최대한 골든타임(4분)을 지킬 수 있으며, 1차 발견자가 신속하고 정확한 심폐소생술을 실시할 수 있어 생존율을 한층 더 높일 것으로 기대한다.

• Corrosion Science and Technology
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• 제8권4호
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• pp.162-169
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• 2009

Pure titanium and its alloys are drastically used in implant materials due to their excellent mechanical properties, high corrosion resistance and good biocompatibility. However, the widely used Ti-6Al-4V is found to release toxic ions (Al and V) into the body, leading to undesirable long-term effects. Ti-6Al-4V has much higher elastic modulus than cortical bone. Therefore, titanium alloys with low elastic modulus have been developed as biomaterials to minimize stress shielding. For this reason, Ti-30Ta-xZr alloy systems have been studied in this study. The Ti-30Ta containing Zr(5, 10 and 15 wt%) were 10 times melted to improve chemical homogeneity by using a vacuum furnace and then homogenized for 24 hrs at $1000^{\circ}C$. The specimens were cut and polished for corrosion test and Ti coating and then coated with TiN, respectively, by using DC magnetron sputtering method. The analyses of coated surface were carried out by field emission scanning electron microscope(FE-SEM). The electrochemical characteristics were examined using potentiodynamic (- 1500 mV~+ 2000 mV) and AC impedance spectroscopy(100 kHz~10 mHz) in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. The equiaxed structure was changed to needle-like structure with increasing Zr content. The surface defects and structures were covered with TiN/Ti coated layer. From the polarization behavior in 0.9% NaCl solution, The corrosion current density of Ti-30Ta-xZr alloys decreased as Zr content increased, whereas, the corrosion potential of Ti-30Ta-xZr alloys increased as Zr content increased. The corrosion resistance of TiN/Ti-coated Ti-30Ta-xZr alloys were higher than that of the TiN-coated Ti-30Ta-xZr alloys. From the AC impedance in 0.9% NaCl solution, polarization resistance($R_p$) value of TiN/Ti coated Ti-30Ta-xZr alloys showed higher than that of TiN-coated Ti-30Ta-xZr alloys.