요중 비소농도와 N-acetyl-β-D-glucosaminidase 농도와의 관련성 평가

이용찬,임동혁,엄상용,김용대,김헌 충북대학교 의과대학 충북대학교 의학연구소 2010 忠北醫大學術誌 Vol.20 No.1

Purposes: This study was performed to evaluate the possibility of impairment of renal tubular function by exposure to inorganic arsenic of low concentration. Materials and methods: Study subjects were 867 individuals (365 men and 502 women) who resided around abandoned mine areas in Chungbuk Province, Republic of Korea. Information about the life style, drinking water type, seafood intake, and mine working history was gathered, and urinary arsenic concentration and N-acetyl-β-d-glucosaminidase (NAG) activity were measured. The correlation between arsenic concentration and urinary NAG activity was tested in groups classified according to urinary NAG activity and seafood consumption prior to urine sampling. Results: No statistically significant difference in urinary arsenic concentrations was observed between different gender and age groups. The participants those who ate seafood within three days before the urinary sample showed a higher mean urinary arsenic concentration than those who did not. In a correlation analysis between natural logarithm of urinary arsenic concentrations and that of urinary NAG activities, no statistical significance was found in a total sample as well as within a gender group. In a group with the urinary arsenic concentrations higher than the geometric mean and the urinary NAG activities higher the geometric mean, the correlation coefficient between two variables was 0.182 and significant. (p-value<0.05) Conclusions: It is suggested that renal tubular damage could be induced by non-occupational exposure to low level inorganic arsenic. 연구목적 : 본 연구는 폐금속광산 주변지역 주민들을 대상으로, 저농도 비소노출에 의하여 신세뇨관 기능이상이 유발될 수 있는지를 평가하는 것을 목적으로 시행하였다. 대상 및 방법 : 충청북도에 소재하고 있는 폐금속광산의 주변에 거주하는 주민 867명을 대상으로 직접 면접조사를 실시하였다. 대상자의 소변을 채취하여 요중 비소농도와 요중 N-acetyl-β-D-glucosaminidase (NAG) 활성을 측정하였고, 조사대상자를 역학적 변수에 따라 구분하여 두 변수 사이의 상관관계를 분석하였다. 결과 : 소변시료를 채취하기전 3일 이내에 해산물을 섭취한 사람들의 요중 비소농도는 그 기간동안 해산물을 섭취하지 않은 사람들의 농도에 비하여 유의하게 높았다. 조사 대상자들의 요중 NAG 농도의 평균값은 남녀차이가 없었으나, 65세 미만 대상자와, 표본을 채취하기 전 3일 이내에 해산물을 섭취한 사람들의 요중 NAG 활성도의 평균값은 그렇지 않은 사람들에 비하여 유의하게 낮았다. 요중 비소농도가 기하평균 이상이고, 요중 NAG 활성이 기하평균 이상인 군에서 두 변수의 상관관계가 0.182 로 유의하였다. 결론 : 정상범위의 비소 노출이라도 요중 비소농도가 8.28 μg/g creatinine을 초과하는 경우에는 미세한 신장손상을 유발할 가능성이 있으며, 해산물을 섭취함으로써 체내에 흡수되는 비소는 이러한 신독성이 거의 없다.

상해증권거래소의 거래제도와 특성

정헌용 남서울대학교 2011 남서울대학교 논문집 Vol.17 No.2

The Shanghai Stock Exchange(SSE) is the most preeminent stock market in mainland China in terms of listed companies, number of shares of listed, total market value, and securities turnover in value. SSE composite index takes December 19, 1990 as the base day and the total market capitalization of all the listed stocks on the same day as the base period, with a base of 100 points. It was published from July 15, 1991and is the most widely used index in China's securities market. We examine the daily stock returns over the eleven years from January 4, 2000 through December 30, 2010. Because of the test statistics of significant skewness, excess kurtosis, autocorrelations, it is reasonable to empoly GARCH models. We use the univariate GARCH(1,1)-M model developed by Engle et al.(1987).The results of the estimation of the GARCH(1,1)-M model for SSECI daily returns show that the risk premium effect on mean equation is not significant. Using the GARCH(1,1)-M model with exogenous variables, we find significant information spillover effect from KOSPI to SSECI and from SSECI to KOSPI in the mean equation. But we cannot find significant information spillover effect from KOSPI to SSECI and from SSECI to KOSPI in the variance equation. Key Words : SSE, SSECI, KOSPI, GARCH model, spillover effect

주식시장간 수익률 전이

정헌용 남서울대학교 2012 남서울대학교 논문집 Vol.18 No.2

The purpose of this study is to examine the relevence of return among stock markets in countries. We use Granger causality test to examine the revelence existing in 9 Asian countries and U.S.A. before and after 1997 Asian financial crises. As a result, first, in the total period, US stock market return transmitted to Japan, Korea, Hong Kong, and Singapore stock markets. Japan stock market return transmitted to US, Singapore, and Indonesia stock markets. And Korea stock market return transmitted to US, Malaysia, Indonesia, and Thailand stock markets. Second, in the before Asian financial crises period, we do not find the relevence of return among stock markets in countries. Third, in the after Asian financial crises period, US stock market return transmitted to Japan, Korea, Hong Kong, and Singapore stock markets. Japan stock market return transmitted to US, Hong Kong, and Singapore stock markets. And Korea stock market return transmitted to US, Hong Kong, Malaysia, Indonesia, and Thailand stock markets. The results suggest substantial increased Asian stock market comovement. This implies that the benefits of diversification within the 9 Asian stock markets have decreased over the recent years. Key Words : Granger causality, KOSPI, return spillover

수중 가청음에 의한 쏨벵이의 청각능력 : 2. 청각 임계비

이창헌,박용석,문종욱,강창익,김고환,서두옥 제주대학교 해양연구소 1999 해양자원연구소연구보고 Vol.23 No.-

수중 가청음은 어군의 행동 제어와 해양목장화에서 음향 순치에 많이 이용되고 있다. 수중 가청음에 의한 어류반응 해석을 하기 위해서는 물고기의 청각능력을 정확히 파악할 필요가 있으며,오래전부터 여러물고기의 청각능력을 관련된 연구가 수행되었다.

수중 가청음에 대한 멸치 어군의 행동 반응

이창헌,문종욱,박용석,최찬문,서두옥 제주대학교 해양연구소 1998 해양자원연구소연구보고 Vol.22 No.-

A field experiment was carried out to confirm the effect of underwater sound on the luring of fish school using a surface speaker at the coast of Cheju Island. Underwater sounds that were emitted for the luring of fish school were the pure sound of which frequencies were 200Hz and 300Hz. 1. The sound pressure level of 100Hz. 200Hz. 300Hz. 500Hz and 1000Hz classified by the depth of water at sea were 95dB. 100dB. l00dB 80dB and 60dB at 1m. 90dB. 95dB. 88dB. 70dB and 45dB at 10m. 87dB, 90dB. 82dB. 65dB and 42dB at 20m respectively. 2. The effect of the emitted pure sound of 200Hz and 300Hz was remarkable for luring of fish school in about 30 minutes after sound emission. Then Sound pressure was 120 - 130dB. The lured fish school was the shoal of anchovy 3. The fact that anchovy school geathered at 200Hz and 300Hz suggested that this fish school did not show sensitive response to the change of frequencies.

수면확성기의 음향특성에 관한 연구

이창헌,문종욱,박용석,최찬문,서두옥 제주대학교 해양연구소 1998 해양자원연구소연구보고 Vol.22 No.-

To obtain the fundamental data on a surface speaker made to lure fish school by pure sound, three surface speakers were made of moving coil driver units of 75W and 50W respectively. Their frequency characteristic was measured in the range of 200 - 4mHz that could be used in luring fish school. The results of the measurements in air and sea are follows. 1. The input and output wave forms of a surface speaker were similar to each other in measurement frequencies in air. Then sound pressure of a surface speaker made of 75W driver units among them was over 130dB(0dB re 20μ Pa) in the range of 300 - 400Hz maximally. 2. When the surface speaker with 75W driver units emitted the measurement frequencies at sea. Sound pressure classified by the depth of water were over 140dB at 1m and 120dB at 20m(0dB re 1μ Pa) respectively.

명태의 행동제어용 심전도 도출에 관한 연구

박용석,이창헌,이유철,서두옥 제주대학교 해양연구소 1997 해양자원연구소연구보고 Vol.21 No.-

In the walleye pollock. Theragra chalcogramma. which has a heart with a strong electromotive force, the ECGs were found to be recordable by electrodes placed in the water from fish's body. The day on the experiment, fish was operated on in order to install a leading-out bipolar electrode. This electrode was used for recording of the cardiosignal of the fish on a digital storage oscilloscope. The electrode was made from a fish book which was re-shaped according to the shaped of fish heart and body surface. This hook was then connected to the lead-code insulated with paint, and the connecting part was covered with paint. The pointed end was stripped off slightly for conduction of electricity and the another pointed edge was used for hooking the electrode into the chest cavity. QRS complex of the ECG was marked. The amplitude of QRS complex was about 0.1-lmV. This method enabled us to observe the heart beat rate of the walleye pollock under least disturbed state. Ordinary heart beat rate was not quite regular. Very slight stimulation was enough to bring about cardiac inhibition. which was also accompanied by a considerable reduction in the amplitude of the QRS. After rough treatment. such as sound stimulus or electric shock. the heart beat rate showed remarkable decrease. reaching a value a few times lower than the normal level.

Chloral hydrate/Hydroxyzine과 Midazolam/Meperidine의 경우 투여 진정효과에 관한 비교 연구

김용헌,김지연,박기태 大韓小兒齒科學會 2005 大韓小兒齒科學會誌 Vol.32 No.2

본 연구의 목적은 소아 환자의 치과 진료를 위한 진정요법 시 chloral hydrate와 hydroxyzine의 경구 투여와 midazolam과 meperidine의 경구 투여간의 임상적인 진정효과 및 합병증 발생 여부를 비교하는 것이다. 삼성서울병원 소아치과를 내원한 환아 중 ASA I또는 Ⅱ에 해당하는4세 미만의 아동 15명을 대상으로 하여 한 달여 간격으로 두 차례에 걸친 진정요법을 시행하였다. 2회의 진정요법 중 1회는 chloral hydrate (60mg/kg)/hydroxyzine(25mg)을 경구 투여하고 나머지 1회는midazolam(1mg/kg)/meperidine(1mg/kg)을 경구 투여하였으며 투여 순서는 무작위로 정하였다. 두 차례 모두 N₂O-O₂, 흡입진정을 병용하였다. 각 치료과정에 따른 진정효과는 Houpt Scale(수면, 움직임, 울음, 전반적인 행동 지수)로 측정하였고 pulse oximeter를 이용하여 저산소증의 유무를 비교, 평가하고 약물 투여 후 구토의 여부를 함께 평가하여 다음과 같은 결과를 얻었다. Chloral hydrate와 hydroxyzine을 경구 투여한 군이 midazolam과 meperidine을 경구 투여한 군보다 전반적인 행동 지수에서 통계학적으로 유의하게 우수한 결과를 보였으며 어느 군에서도 저산소증은 보이지 않았다. 본 연구에서는 chloral hydrate와 hydroxyzine의 경구 투여가 midazolam과 meperidine의 경구 투여보다 우수한 진정효과를 보이는 것으로 판단된다. The purpose of this study was to compare the efficacy and complications of two oral sedative regimens, chloral hydrate(60mg/kg)/hydroxyzine(25mg) versus midazolam(1mg/kg)/meperidine(1mg/kg) for the sedation of pediatric dental patients. Fifteen patients(mean age 36.2months, range 24-47months), ASA Class I or II, who needed at least two restorative dental procedures were selected in this double-blind, randomized study. All subjects were randomly assigned to receive either chloral hydrate/hydroxyzine or midazolam/meperidine and 50% N₂O/0₂ was administered at each appointment. Behavior assessment(sleep, movement, crying, overall behavior) was made using Houpt Sedation Rating Scale and physiologic parameters(pulse rate, oxygen saturation) were monitored using pulse oximeter. The incidence of hypoxia(SpO2 90% or less, at least 10s duration) and vomiting was recorded. Patients sedated with chloral hydrate/hydroxyzine showed significantly better overall behavior score than patients sedated with midazolam/meperidine. There was no clinically significant difference in the incidence of hypoxia and vomiting. It was concluded that oral administration of chloral hydrate/hydroxyzine is more effective than midazolam/meperidine for the sedation of pediatric dental patients.

한국증권시장에서의 월중효과에 관한 연구

정헌용 남서울대학교 1999 남서울대학교 논문집 Vol.5 No.-

This paper examines inter-month effect for KOSPI from 1980.1-1998.12 In particular I examine the behavior of returns of the month. 1 found that there existed significantly high average returns for eight days after the 22nd trading day within a month. I explored a number of explanations for these results and concluded that they could not be explained when I considered January effect. Especially significant positive eight days' returns are remarkable in bear market. Thus I highlight in this paper the importance of considering the microstructure of financial markets in empirical tests of market anomalies.

급성심근경색증의 조기진단에 있어서 Myoglobin의 진단적 의의

이정헌,김종근,정병천,서강석,박정배,조용근,류재근,전재은,채성철,박의현 大韓應急醫學會 1999 대한응급의학회지 Vol.10 No.2

Background: Exact and early diagnosis of acute myocardial infarction (AMI) is essential for the subsequent routine management of this frequent cardiovascular disease. Currently, AMI has been diagnosed using the combination of the history, electrocardiogram(ECG), and biochemical markers of myocardial necrosis. At present, many biochemical markers are used to diagnose AMI. In this study, the predictive values of serum myoglobin and creatine kinase-MB(CK-MB) were compared in the emergency department. Methods: Fifty-four consecutive patients who presented within 12 hours from onset of chest pain of presumed cardiac origin were enrolled into the study. Patients with trauma or renal failure were excluded. The serial serum myoglobin and CK-MB levels were obtained prospectively at admission and 2, 4, 6, 12, 24 and 48 hours after admission. We compare the levels of serum myoglobin and CK-MB within 2, 4, 6, 8, 10, 12, 24, and 48 hours after symptom onset respectively. And we compare the sensitivity, specificity, positive predictive value, and negative predictive value of myoglobin and CK-MB. Results: using World Health Organization criteria, 28 AMI patients were identified. Mean time from symptom onset to presentation was 4.1±1.3 hours. The predictive values of serum myoglobin were better than those of CK-MB within 6 hours after symptom onset. But, 6 hours after symptom onset, the predictive values of CK-MB were better than those of serum myoglobin. The false positive cases of serum myoglobin were 3-one was lung cancer with pleural effusion and the others were unstable angina. The false positive cases of CK-MB were 6-one case was viral myocarditis and the ohters were unstable angina. Conclusion: To compare the serum myoglobin and CK-MB in the diagnosis of AMI, serum myoglobin had better predictive values than CK-MB within 6 hours after symptom onset and useful in the early diagnosis of AMI. But, 6 hours after symptom onset, CK-MB had better predictive values than serum myoglobin and useful in following up.