• 대한치과의사협회지
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• 제55권2호
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• pp.156-164
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• 2017

Purpose: The aim of this in vitro study was to assess changes in remineralization by stimulated human saliva over a short period of 48 hours with quantitative light-induced fluorescence (QLF) technology. Materials and Methods: Bovine incisor surfaces were demineralized for 10 days. Two types of stimulated saliva were collected from 7 healthy persons. 24 hours after tooth brushing (Stimulated saliva group) and immediately after tooth brushing with 1,000 ppm NaF dentifrice (Dentifrice saliva group). The specimens were immersed in saliva and fluorescence images were obtained by QLF-digital (QLF-D $biluminator^{TM}$,) at 2, 4, 6, 12, 24, and 48 hours fluorescence loss (${\Delta}F%$) of the lesions. A paired t-test was performed to assess fluorescence differences between before (${\Delta}F_{baseline}$) and after (${\Delta}F_{treatment\;time}$) the remineralization process. Results: Before the remineralization, the mean ${\Delta}F_{baseline}$ of the initial demineralized specimens was $-18.42{\pm}0.15$ (%). In both groups, the ${\Delta}F$ values obtained at baseline and after 2 hours were statistically significant (P < 0.001), indicating recovery of the lesions by approximately 40% after 2 hours. After 48 hours, remineralization rates were slightly higher (49%) for the stimulated saliva group than for the dentifrice saliva group (41%), but the difference was not statistically significant. Conclusions: With QLF minute degrees of remineralization by saliva can be measured in periods as short as 2 hours. Additionally no significantly higher effects of remineralization were observed in the dentifrice saliva group when compared to the stimulated saliva group.

• 한국식품영양과학회지
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• 제45권4호
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• pp.542-550
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• 2016

굴 가수분해물의 이취 제거를 위한 가수분해 및 발효의 최적 조건과 이의 항산화 효과를 검토하였다. 이취 제거를 위한 굴 가수분해물의 최적 추출 조건은 Neutrase를 이용하여 E/S 3.3%, $50^{\circ}C$, 8.3시간이었으며, 발효 공정은 $24^{\circ}C$에서 glucose 0.5%와 Saccharomyces cerevisiae를 5% 접종하였다. 굴 가수분해 발효물의 구성 아미노산은 25.7%에 해당하였으며, Glu, Asp, Lys, Leu, Arg, Gly 및 Ala이 전체의 61.2%를 차지하였다. 유리 아미노산 조성의 경우 Leu, Ala, Phe, Val 및 Tau의 순으로 높게 나타났다. 또한 무기질 함량은 Na, P, K, Zn, Fe이 높게 나타났으며, 정상 간세포주인 Chang cell에 대한 독성은 나타나지 않았다. 이상의 결과로 미루어 S. cerevisiae에 의해 수산물의 이미취를 masking 할 수 있으나, 기능성 원료로 사용하기 위해 최종 제품의 카드뮴 함량을 저감시킬 대책이 필요하다.

• 한국식품영양과학회지
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• 제43권4호
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• pp.557-563
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• 2014

본 연구에서는 가압가열 및 microwave 처리가 gliadin의 항원성에 미치는 영향을 살펴보기 위해 강력분에 가압가열과 microwave를 단독 또는 병행으로 처리하여 Ci-ELISA, SDS-PAGE 및 immunoblotting을 실시하였다. 가압가열 처리의 경우 시간이 길어질수록 IgG와의 결합력이 감소하였으며, 특히 50분 처리구에서 약 87%로 가장 낮은 결합력을 보였다. 또한 SDS-PAGE와 immunoblotting 결과에서도 무처리구에서 강하게 보였던 gliadin band가 가압가열 처리에 의해 거의 소실되고 항체와 반응하지 않았다. 가압가열 및 microwave를 병행 처리 시도 마찬가지로 gliadin의 결합력이 감소하였으며, 처리구 중 가압가열 50분, microwave 5분 처리구에서 약 93%로 가장 낮은 결합력을 보였다. 반면 microwave를 단독으로 처리한 경우에는 일부 단백질의 변화는 관찰되었으나, 항원성 감소에는 효과가 없음을 확인하여 단백질 변화가 항원성에는 큰 효과를 준 것 같지 않다. 이상의 결과를 통해 가압가열 단독 처리 및 가압가열 및 microwave의 병행처리 시 gliadin의 항원성이 감소함을 확인하였다.

• 공업화학
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• 제20권4호
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• pp.375-380
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• 2009

폴리에피클로로히드린 고무(PECH)의 염소기를 높은 분해열을 갖는 아지드기(-$N_3$ )로 치환시켜 아지드화 PECH (Az-PECH)를 제조한 후 이를 열가소성수지인 스티렌-아크릴로니트릴(SAN)과 고무/플라스틱 비율이 무게비로 80/20, 70/30, 60/40이 되도록 블렌딩하고, 제조된 블렌드 필름의 상용성, 기계적물성 및 탄성복원력을 평가하였다. Az-PECH의 $N_3$기 치환도가 50% 이하인 블렌드의 경우 단일 유리전이온도를 나타내어 상용성 블렌드임을 알 수 있었으며, 고무함량이 클수록 블렌드의 우수한 유연성과 탄성복원력을 나타내었다. $N_3$ 치환도가 75%인 블렌드에서는 상분리가 일어나며 유연성과 탄성복원력이 상용성 블렌드에 비해 저하되었다. 상용성을 갖는 블렌드들은 모두 고무특성과 함께 반복적인 가열성형이 가능한 전형적인 열가소성탄성체임을 확인하였다 또한, PECH의 $N_3$ 치환도가 크고, $N_3$기를 갖는 고무함량이 큰 블렌드일수록 연소시 더 큰 불꽂을 발생시키는 것을 관찰할 수 있었다.

• Korean Journal of Acupuncture
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• 제29권2호
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• pp.300-314
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• 2012

Objectives : This study is to observe the changes in the expression of neurotransmitters, such as NO, nNOS, and NE, upon the needle insertion to the sea points, which is one of the five transport points. Methods : Needles were inserted into rats, on both left and right sides of all sea points, including the LU5, PC3, HT3, LI11, TE10, SI8, SP9, LR8, KI10, ST36, GB34, and BL40, which are the sea points of five transport points for 12 meridian vessels. After insertion, needles were retained for five minutes. After the retention, blood was drawn via cardiac puncture, and tissues of each point near meridian vessels were extracted to examine the changes in the expression of NO, nNOS and NE. Results : In terms of the effect in NO production, there was a significant decrease only in the LU5 point, whereas there was a significant increase in the TE10 point alone. In terms of the expression of nNOS within tissues, none of the experimental groups showed significant changes based on the results of immunohistochemistry and western blotting. Regarding the formation of norepinephrine within tissues, the HT3, SP9, and KI10 point showed a significant decrease, while the PC3 and LR8 point showed a significant increase. Production of plasma norepinephrine was significantly increased at the TE10, SP9, LR8, GB34, and BL40 point. Conclusions : The effect of needles applied at the sea points of five transport points of 12 meridian vessels on the functions of NO, nNOS, and NE could be observed, and it is considered that the effect of needle stimulation on nervous system disorders could be studied through additional researches based on this one.

• 한국대기환경학회지
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• 제26권5호
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• pp.543-553
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• 2010

Almost five million citizens a day are using subways as a means of traffic communication in the Seoul metropolitan. As the subway system is typically a closed environment, indoor air pollution problems frequently occurs and passengers complain of mal-health impact. Especially $PM_{10}$ is well known as one of the major pollutants in subway indoor environments. The purpose of this study was to compare the indoor air quality in terms of $PM_{10}$ and to quantitatively compare its source contributions in a Seoul subway platform before and after installing platform screen doors (PSD). $PM_{10}$ samples were collected on the J station platform of Subway Line 7 in Seoul metropolitan area from Jun. 12, 2008 to Jan. 12, 2009. The samples collected on membrane filters using $PM_{10}$ mini-volume portable samplers were then analyzed for trace metals and soluble ions. A total of 18 chemical species (Ba, Mn, Cr, Cd, Si, Fe, Ni, Al, Cu, Pb, Ti, $Na^+$, $NH_4^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, and ${SO_4}^{2-}$) were analyzed by using an ICP-AES and an IC after performing proper pre-treatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the source of particulate matters. $PM_{10}$ for the station was characterized by three sources such as ferrous related source, soil and road dust related source, and fine secondary aerosol source. After installing PSD, the average $PM_{10}$ concentration was decreased by 20.5% during the study periods. Especially the contribution of the ferrous related source emitted during train service in a tunnel route was decreased from 59.1% to 43.8% since both platform and tunnel areas were completely blocked by screen doors. However, the contribution of the fine secondary aerosol source emitted from various outside combustion activities was increased from 14.8% to 29.9% presumably due to ill-managed ventilation system and confined platform space.

• Parasites, Hosts and Diseases
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• 제58권3호
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• pp.315-319
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• 2020

In November 2019 a 5-month-old mixed-breed rabbit presented to Chungbuk National University Veterinary Teaching Hospital, Cheongju-si, Chungbuk, Republic of Korea (Korea) with symptoms comprising pruritus, crusts on skin, poor appetite and reduced defecation. The rabbit was purchased 2 months prior from a pet shop located in a big market, and that the symptoms were first observed about 2 weeks prior to the hospital visit. Physical examination revealed that the patient had crust formation and alopecia on the nose together with lesions on the digits. A skin scraping test was performed using mineral oil and a high density of mites was observed by microscopy. Each mite showed a round, tortoiselike body with 4 comparatively short pairs of legs. The anus was located at the terminal unlike with suspected pathogen, Notoedres cati. Based on morphological characteristics, we identified the mite as Sarcoptes sp. Ivermectin was administered weekly by subcutaneous injection at a dosage of 0.4 mg/kg, and 4 weeks of follow-up study revealed the patient was fully recovered. And no more mites were detected from the case. This is the first case report of sarcoptic mange in a pet rabbit in Korea.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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• pp.472-472
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• 2004

Numerous studies on urban groundwater have been carried out in many other countries. Urban groundwater shows a unique hydrologic system because of complex urban characteristics such as road pavement, sewers and public water supply systems. These urban facilities may change the characteristics of groundwater recharge but contaminate its quality as well. There have been several researches on urban groundwater in Seoul. Seoul has been industrialized very rapidly so that the city has large population. The recent population in Seoul amounts to more than ten millions, corresponding to a very high density of about 17, 000 people/km$^2$. Therefore, many factors affect the groundwater quality and quantity in Seoul. Nowadays, groundwater in Seoul is being extracted for construction, industrial use, and drinking and so on. There are 15, 714 wells in Seoul and its annual usage is 41, 425, 977m$^3$(in 2001). Therefore, systematic studies are needed to properly manage and use the groundwater in Seoul. The purposes of this study in progress are to identify geochemical characteristics of groundwater in Seoul and to determine the extent of groundwater contamination and its relationship with urban characteristics. For this study, groundwater was sampled from more than 400 preexisting wells that were randomly selected throughout the Seoul area. For all samples, major cations together with Si, Al, Fe, Pb, Hg For 200 samples among them, TCE, PCE, BTEX were also analyzed by GC. Our study shows that groundwater types of Seoul are distributed broadly from Ca-HCO$_3$ type to Ca-Cl＋NO$_3$ type. The latter type indicates anthropogenic contamination. Among cations, Ca is generally high in most samples. In some samples, Na and K are dominant. The dominant anions change widely from HCO$_3$ to Cl＋NO$_3$. The anion composition is considered to effectively indicate the contribution of distinct anthropogenic sources. In addition, major ions are positively proportional to total dissolved solid (TDS) except K and NO$_3$. Thus, we consider that TDS may be used as an effective indicator of the extent of pollution. However, the increase of TDS may result from increased water-rock interaction. To determine the extent of groundwater contamination, it is needed to figure out the baseline water quality in Seoul. Furthermore, detailed geochemical studies are required to find out pollution sources and their corresponding hydrochemical parameters.

• 한국식품위생안전성학회지
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• 제26권1호
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• pp.57-63
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• 2011

다양한 식품첨가물의 사용과 소비가 증가하고 있으며, 최근 어린이기호식품을 통한 타르색소 등 첨가물의 섭취량이 늘어가고 있다. 본 연구는 시중 유통중인 학교 주변 어린이기호식품을 대상으로 식용색소 황색 제 4호(Y4), 황색 제5호(Y5), 청색 제1호(B1), 청색 제2호(B2), 적색 제2호(R2), 적색 제3호(R3), 적색 제40호(R40), 적색 제102호(R102), 녹색 제3호(03)등 국내 허용된 타르색소 9종에 대한 실태조사를 실시하고 모니터링 분석을 통하여 노출량, 위해성 평가를 수행하였다. 그 결과, 어린이기호식품 82종(과자류 3종, 캔디류 71종, 초콜릿 4종, 음료류 4종)을 통한 타르색소의 섭취수준이 매우 낮고 상위섭취군(95th percentile)에서도 일일섭취허용량(ADI)의 0~3.56%에 불과하였다. 결론적으로 어린이기호식품 섭취에 따른 어린이의 타르색소에 대한 위해성 수준은 매우 낮은 것으로 판단되며, 타르색소 9종 각각의 일일추정섭취량(EDI)이 평균적으로 FAO/WHO에서 권장하는 양보다 낮아 안전한 수준으로 평가되었다. 그러나 어린이기호식품에 사용되는 식품첨가물은 보편적으로 몇 가지 첨가물이 복합적으로 사용되고 있어 어린이의 식품첨가물 섭취에 대한 지속적인 모니터링과 그에 따른 적절한 관리가 필요할 것이다.

• 한국식품영양과학회지
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• 제26권2호
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• pp.229-235
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• 1997

국내산 밀(그루, 수원 257, 은파, 조광, 탑동)과 수입 밀(ASW, DNS)을 70% 제분수율로 제분한 밀가루와 통밀의 단백질, 아미노산, 구성당 및 무기질 조성을 살펴본 결과 다음과 같다. 국내산 통밀중 은파와 탑동의 경우 단백질 함량이 약 15%을 나타내었고, 제분한 밀가루는 약 1% 가량 낮은 함량을 보였다. 국내산 밀가루에 있어서 아미노산 조성은 점탄성에 영향을 주는 것으로 알려진 글루탐산과 프롤린의 함량이 높았고, 제한 아미노산은 국내산이 ASW 보다는 높고 DNS 보다는 낮게 나타났는데 특히, 수원 257과 탑동의 제한 아미노산 함량이 높았다. 제분 전후의 아미노산 함량에 있어서 글루탐산과 프롤린은 증가하나 리진과 트레오닌 등의 제한 아미노산 양은 감소하였다. 구성당의 조성은 통밀의 경우 밀가루 보다 아라비노스와 자일로스의 함량이 높았으며 글루코스의 함량이 낮게 나타났다. 한편, 국내산 밀은 외국산 밀에 비하여 아라비노스와 자일로스의 함량이 높게 나타났다. 국내산 밀가루와 통밀에 있어서 무기질 함량 중 인, 칼륨, 칼슘의 함량은 ASW와 DNS에 비하여 모두 높게 나타났으며, 알루미늄과 실리카의 함량은 비슷하거나 소량 증가하였다.