• 한국식품과학회지
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• 제14권4호
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• pp.336-341
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• 1982

미역김의 제조와 이화학적 특성에 관한 계속 연구로 실시한 미역김의 조직화학적 특성 연구 결과는 다음과 같다. 미역잎은 표층, 피층, 속층으로 구성되어 있는데 미역김의 결합단면을 광학현미경으로 관찰한 결과 피층과 속층이 완전히 파괴되었고 표층세포끼리 결합되어 있었다. 미역김 절편을 $Na_2CO_3$용액 처리로 알진산을 추출한 후 광학현미경으로 검경한 결과 알진산이 추출된 결합부위는 periodic acid schiff reagent반응이 나타나지 않았으며, 한편 미역잎을 $Na_2CO_3$용액으로 미리 처리하여 알진산을 추출한 후에는 정상적인 미역김을 제조할 수 없었고 비정상적인 결합구조이었으므로 알진산이 미역김의 결합물질임을 확인할 수 있었다. 미역김의 결합부위를 전자현미경으로 관찰한 결과 알진산의 결합위치는 미역김의 표층세포막과 세포막사이임이 밝혀졌다. $Na_2CO_3$용액을 처리한 미역잎으로 제조한 비정상적인 미역김의 결합구조는 표층세포껍질로 인지되는 물질만이 서로 엉켜 있었다.

• Corrosion Science and Technology
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• 제3권6호
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• pp.251-256
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• 2004

Exposure of zinc samples in simulated acid rain solution (SARS) was investigated under a periodic wet-dry conditions using an AC impedance technique. The periodic wet and dry exposure consisted of the immersion of zinc samples in SARS for one hour followed by exposure to 7 hours drying at 60% RH. Phases of the corrosion products were indentified by X-ray diffraction (XRD). The influence of relative humdiity (RH), temperature, and surface inclination on the atmospheric corrosion of zinc is described. The reciprocal of polarization resistance (1/Rp) decreases rapidly during the initial stages then slowly and eventually attains a steady state as exposure time progresses. The average of reciprocal of polarization resistance per cycle, (ARPR) was calculated and found to decrease as number of exposure cycle increases. An increase of temperature enhances the corrsion rate of zinc. The values of ARPR, of a sample inclined at 30 o are lower than those for a sample oriented horizontally. The experiment result shows a pronounced dependence of reciprocal of polarization resistance on RH. Exposure in the presence of carbonate anions gives rise to more protective corrosion products than in nitrate anion solution. The corrosion mechanism during the initial stages of atmospheric zinc corrosion under wet-dry cyclic conditions is suggested.

• Korean Membrane Journal
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• 제11권1호
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• pp.21-28
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• 2009

We investigated the effect of organic materials on membrane fouling in advanced drinking water treatment by a hybrid module packed with granular activated carbon (GAC) outside multi-channel ceramic microfiltration membrane. Synthetic water was prepared with humic acid and kaolin to simulate natural water resouces consisting of natural organic matter and inorganic particles. Kaolin concentration was fixed at 30 mg/L and humic acid was changed as 2~10 mg/L to inspect the effect of organic matters. Periodic back-flushing using permeate water was performed for 10 sec per filtration of 10 min. As a result, both resistance of membrane fouling (Rf) and permeate flux (J) were influenced highly by concentration of humic acid. It proved that NOM like humic acid could be an important factor on membrane fouling in drinking water treatment. Turbidity and UV254 absorbance were removed up to above 97.4% and 59.2% respectively.

• Restorative Dentistry and Endodontics
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• 제20권2호
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• pp.843-855
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• 1995

Occupational Dentistry was introduced in Korea about 70 years ago. During the colonial period occupied by Japan till 1945, there were few documents about industrial dentistry, furthermore most cases of occupational diseases and accidents might have been concealed intentionally by the colonial government. After being an independent country, several dentists made efforts to set up 'Preventive Dentistry for Workers' performing specific oral health surveys, even though which were stopped by Korean War. In 1960s' and 1970s', some investigations of oral status were carried out intermittently for specific small groups;white-collar workers, mentally retarded person, buddhist monks and crews of ocean liners. At the same time there was important study in Korean history of occupational dentistry, which was 'a comparison of the oral hygiene conditions in the female workers of a spinning factory at intervals of 30 years.' In 1980s', young researchers began to give attention to erosion of the teeth due to sulphuric acid in the acid-related industry and dental caries due to sugar and flour in the sweets industry. After being democratic labor union movement activated in 1987, hidden and suppressed occupational diseases under the military dictatorship were exposed and flushed in the newspapers. It was shocking for all people that 15-year old boy had been dead due to mercury intoxication after 3-month employment in 1988. In 1990s', the activity for studying oral status of workers in their workplaces was launched and 'Occupational Accidents and Diseases in Oral and Maxillofacial Field' was published. And also The Korean Association of Occupationl Dentistry was established. Oral health examination of workers at the time of employment and of workers exposed to 5 special chemicals at the time of routine special health examination was adopted in 1992, and epocally oral health examination was also included in periodic routine examination of workers' health in 1995. So, occupational dentistry in Korea should cope with the changing needs of working environment and the altering scheme of health examination.

• Applied Microscopy
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• 제51권
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• pp.5.1-5.7
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• 2021

The olfactory organs of two African lungfishes, Protopterus amphibius and P. dolloi, were investigated using a stereo microscope and a compound light microscope and were described anatomically, histologically, and histochemically. Like other lungfishes, these species present the following general features: i) elongated olfactory chamber (OC), ii) anterior nostril at the ventral tip of the upper lip, iii) posterior nostril on the palate of the oral cavity, iv) lamellae with multiple cell types such as olfactory receptor neurons, supporting cells, basal cells, lymphatic cells, and mucous cells (MC), and vi) vomero-like epithelial crypt (VEC) made of glandular epithelium (GE) and crypt sensory epithelium. Some of these features exhibit differences between species: MCs are abundant in both the lamellar and inner walls of the OC in P. amphibius but occur only in lamellae in P. dolloi. On the other hand, some between feature differences are consistent across species: the GE of both P. amphibius and P. dolloi is strongly positive for Alcian blue (pH 2.5)-periodic acid Schiff (deep violet coloration), and positive with hematoxylin and eosin and with Masson's trichrome (reddish-brown staining), unlike the MCs of the two species which stain dark red with both Alcian blue (pH 2.5)-periodic acid Schiff and Masson's trichrome but respond faintly to hematoxylin and eosin. The differing abundance of MCs in the two lungfishes might reflect different degrees in aerial exposure of the olfactory organ, while the neutral and acid mucopolysaccharide-containing VEC, as indicated by staining properties of the MCs, is evolutionary evidence that P. amphibius and P. dolloi are the closest living relatives to tetrapods, at least in the order Dipnoi.

• 한국식품영양과학회지
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• 제28권2호
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• pp.326-332
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• 1999

In order to develope useful components and to apply in food additives, various components in the leaves of baechohyang were determined according to picking date. Moisture and ash were reached to 74~82%, 1.5~3.4%, respectively, and major sugars were fructose, glucose, sucrose, and maltose. Glutamic, aspartic acid, and leucine constituted the main component amino acids and their contents were relatively higher in the samples of summer and young leaves. Among free amino acids, histidine showed the highest components and methionine were the lowest. Potassium, calcium, and sodium were main mineral components. The content of ascorbic acid were 6.6~9.2mg% and seasonal variations were negligible. Muture leaves contained more polyphenols as much as 108~181mg% and the amount of bound fractions were much more. Periodic evaluation of phenolic compounds were made and major components of bound fractions were caffeic, syringic, and ferulic acid.

• 대한화장품학회지
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• 제45권1호
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• pp.9-17
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• 2019

본 연구에서는 천연 보습인자의 구성 성분인 L-${\alpha}$-아미노산을 피부에 주기적으로 반복 도포하여 일반적으로 알려진 보습뿐 만 아니라 L-${\alpha}$-아미노산을 피부 톤과 결의 개선제로 활용하였다. L-${\alpha}$-아미노산의 알킬기(R)의 극성과 비극성에 따라 두 그룹으로 나누어 각질케어 효능을 확인하였다. 그 결과, 극성 알킬기를 갖는 L-${\alpha}$-아미노산 콤플렉스(L-${\alpha}$-아미노산-콤플렉스-1)가 비극성 알킬기를 갖는 L-${\alpha}$-아미노산 콤플렉스(L-${\alpha}$-아미노산-콤플렉스-2)에 비해 21% 향상된 효능을 나타내었다. 임상 실험을 위해 20 - 40대 11인의 여성에게 실험군으로서 L-${\alpha}$-아미노산 콤플렉스-1을 포함한 에멀전을 오른쪽 뺨에 8주간 매일 도포하고 대조군으로서 L-${\alpha}$-아미노산 콤플렉스-1를 포함하지 않은 에멀전을 왼쪽 뺨에 같은 방법으로 도포하였다. 피부 톤의 개선은 $JANUS^{(R)}$ 장비를 통해 측정하고 이미지분석 소프트웨어를 이용하여 분석하였으며, 피부 결의 개선은 phaseshift rapid in-vivo measurement of the skin (PRIMOS)장비를 이용하여 기기적으로 측정하고 분석하였다. 그 결과, 피부 톤 11.7%, 피부 결 6.7%의 개선을 확인하였다. 또한 피험자에게 심미적으로 느껴지는 개선에 대해 설문조사를 실시하여 피부개선의 체감도를 바탕으로 기기측정 결과를 통해 나타난 L-${\alpha}$-아미노산 도포의 효능을 평가하였다. 본 연구 결과를 통해, 약산성(pH 6.5)조건에서 피부 자극을 유발하지 않음과 동시에 생리학적인 개선을 통한 피부 톤과 결의 개선을 기대할 수 있으며, 화장품 소재로서 심미적 만족감을 줄 수 있는 물질로 L-${\alpha}$-아미노산이 활용될 수 있을 것이라 생각된다.

• 대한수의학회지
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• 제47권4호
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• pp.443-447
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• 2007

A 7-year-old, female snow goose (Anser caerulescens hyperboreus) with history of decreased activity for 2 month died in Daejeon Zoo Land in September 2006. At necropsy, granulomatous pneumonia and hepatomegaly with multiple cysts were observed. Small masses were found in the spleen. Microscopically, fibrinous pneumonia distributed in most of the lung lobe with pulmonary edema and congestion. Especially, granulomatous inflammation with numerous multinucleated giant cells was observed around the dilated bronchi. To confirm the diagnosis, acid-fast (Ziehl-Neelsen method) and periodic acid-Schiff (PAS) staining was performed. Acid-fast staining showed red bacterial colony indicating tuberculosis. PAS staining was also positive enough to diagnose aspergillus spp. co-infection that was an opportunistic fungi occurring in immuno-compromised animals. Based on the above results, we confirmed that the case submitted was diagnosed as avian tuberculosis.

• Journal of Preventive Medicine and Public Health
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• 제35권3호
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• pp.214-220
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• 2002

Objectives : To investigate the relationship of serum uric acid to cardiovascular risk factors in Korean male workers. Methods : We screened 522 male workers at an electrical manufacturing company by a periodic health examination and a questionnaire survey in 2000. We collected data relating to age, smoking status, alcohol drinking status, body mass index (BMI), blood pressure, serum lipid, fasting blood glucose and serum uric acid. The data were analyzed using a variety of methods, including ANOVA, Pearson's correlation, and multivariate regression analyses. to examine the association between uric acid and cardiovascular risk factors with a cross-sectional study design. Results : The concentration of serum uric acid showed positive associations with BMI, total cholesterol, triglyceride, and LDL-cholesterol; it was also significantly correlated to systolic and diastolic blood pressures. Life-style characteristics, such as smoking and alcohol drinking showed no significant association. From the multivariate regression analyses, BMI, total cholesterol and fasting blood glucose levels were found to be independent positive predictors of uric acid; while age, blood pressure and smoking status give no independent contribution explaining the variability of serum uric acid levels. Conclusions : This study demonstrates that serum uric acid level have a significant association with cardiovascular risk factors, such as BMI, total cholesterol and blood glucose in some Korean male workers.

• 대한족부족관절학회지
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• 제4권1호
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• pp.30-34
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• 2000

The Actinomyces organism is inherent in human as normal flora found in the mouth. Outside of the mouth, this organism can cause actinomycosis. Involvement of the extremity is very rare and atypical. The authors have experienced a case of actinomycosis of the foot and report with the literature review. Histopathologic finding shows multiple sulfur granules. In histochemical stains, periodic acid-Schiff, Gomori methionine silver, and gram stain were positive, and acid fast bacilli stain was negative. The patient was treated with surgical excision and antibiotic administration with Ampicillin for 6 months.