전자부품 제조업 근로자들의 시력변화에 대한 연구

이용만,안규동,이성수,함정오,김화성,리갑수,이병국 순천향의학연구소 1996 Journal of Soonchunhyang Medical Science Vol.2 No.2

근접작업이 시력약화의 원인이 될 수 있는가를 알아보기 위하여 전자부품을 제조하는 2개 사업장에서 1991년에서 1993년까지 입사한 근로자들 중에서 근접작업으로 인정되는 마이크로칩을 조립하는 근접작업자 306명을 조사군으로, 대조군은 세탁기 타이머 및 일반 기계기구를 조립하는 작업자 154명, 계 460명을 선정하였다. 이들 대상자는 1991년 입사자는 1993, 1994, 1995년 시력을 조사하였으며, 1992년 입사자는 1993, 1994, 1995년 3년동안 조사를 하였으며, 1993년 입사자는 1994, 1995년 2년간 시력을 조사하였다. 대상자 중에서 입사시 안경을 착용한 근로자는 82명(17.8%)이었다. 따라서 남자 근로자와 안경착용자를 제외한 여성 근로자들 335명만을 추적 조사하여 다음과 같은 결론을 얻었다. 조사군에서 입사시 시력 1.0 이상이었던 근로자의 분포는 취업 1년 후 약 25-35% 정도 감소하였으며, 2년후에는 약 40-60% 정도의 감소를 나타내었고, 3년 후 약 50-65% 정도로 감소하였고 4년후에는 약 65% 이상 감소하였다. 그러나 대조군에서는 1.0 이상의 시력을 보였던 근로자들의 비율이 취업 1년 또는 2년 후 15-30%의 감소를 보이고 있으나 그 이후에는 큰 변동이 없었다. 이들의 시력변화를 근무년수에 따라 알아보기 위하여 조사된 시력을 순위변수로 하여 Kruskall-Wallis 검정을 시행한 결과 조사군, 대조군 모두에서 근속년수에 따른 순위의 합의 평균이 년차적으로 유의하게 감소하였으나, 입사시부터 근속년수에 따른 조사군과 대조군과의 순위합의 평균에 의한 시력차 비교에서 입사시 조사군의 순위합의 평균이 유의하게 높았던 것이 근무기간에 따라 대조군의 평균이 높아지면서 통계적 유의성이 없고 대체적으로 1년 이후부터 변화가 적은 것으로 나타나 근접작업으로 인한 시력약화를 추정할 수 있었다. This study was carried out to investigate that the close distance works were associated with decreased visual acuity. 306 workers were subjects who had been recruited from 1991 to 1993 in two electronic parts manufacturing factories, and 154 workers were controls who had been employed from 1991 to 1993 in launder machine timer and general machine assembly factories. Subjects who had been employed in 1991 and 1992 were follow up from 1993 to 1995, and subjects who had been employed in 1993 were from 1994 to 1995. The male workers as well as glasses wearing workers were excluded. Only 335 female workers were followed up to study the change of visual acuity. The results were as follows; The rate of workers with visual acuity over 1.0 at recruit year in subjects group was decreased about 25-35% after 1 year, 40-60% after 2 years, 50-65% after 3 years, and 65% after 4 years. While, the rate of workers with visual acuity over 1.0 at recruit year in control group was decreased about 15-30% after 1 or 2 years, and there was no more additional visual acuity reduction after then. Kruskall-Wallis test was performed to investigate the change of visual acuity in subject and control group by work duration. The means scores of ranks in both group were significantly decreased by work duration. The mean scores of ranks in subject group at recruit year were significantly higher than those in control group at recruit year, but these differences were disappeared after 1 year work. Therefore, this suggest that close distance workers may be affected their visual acuity.

무보수 호흡용 보호구 착용이 2차 제련 연작업자들의 연폭로지표에 미치는 영향

이영구,황보영,리갑수,이성수,안규동,이병국 순천향대학교 산업의학연구소 1997 순천향산업의학 Vol.3 No.1

It is often impossible to improve working condition in small scaled lead industries due to inherent old work process and lack of capital to improve it. This is particularly true in secondary smelting industries in Korea. Alternative ways to protect workers in these industries are respiratory protection and job shift if at all possible to less harmful workplace. This study intended to evaluate the effect of maintenance free respirator and job shift of lead workers to other non-lead workplace on the level of lead exposure of workers in terms of blood zinc protoporphyrin as an index of lead absorption and intoxication of lead workers. Seventy three workers of one secondary smelting industry whose work duration was more than 4 months were studied. All workers were classified into 4 groups such as managemental workers(8), non-lead workers(14), lead workers(44) and shift workers(7). Personal data such as age and work duration were collected and air concentration of lead in each workplace were also measured. Blood ZPP was chosen as an index of biological monitoring and was measured regularly once a month for 5 months study period. The results obtained were as follows: 1. There were no significant differences of mean blood ZPP during 5 months study period in management workers and non-lead workers showing the range of 23.1-26.5 ㎍/100ml and 22.2-24.2 ㎍/100ml respectively. 2. Rapid reduction of mean blood ZPP from first month (203.0 ± 106.7 ㎍/ 100ml) to third month (128.4 ± 75.1 ㎍/100ml) was noticed and after 3 months period there was no further reduction of blood ZPP in lead workers. 3. The initial mean blood ZPP of shift workers who moved to non-lead workplace was 394.3 ± 114.9 ㎍/100ml and their mean blood ZPP were steadily decreased every month from 344.3 ± 98.4 ㎍/100ml of first month to129.9 ± 33.5 ㎍/100ml of 4th month). 4. The average reduction rate of blood ZPP based on initial blood ZPP was 37.0% in lead workers for 3 months period and 67.1% in shift workers for 4 months period. With above results it was observed that respiratory protection and work shift could protect lead workers from lead exposure by reducing lead exposure in secondary smelting industry which had fairly bad working condition. But for a complete prevention of lead poisoning, it has certain limitation and should be used as an interim method until fundamental engineering control of workplace.

Superconducting MgB2 Wire Drawing Considering Anisotropic Hardening Behavior and Hydrostatic Effect

Young‑Seok Oh,Ho Won Lee,Kook‑Chae Chung,Duck‑Young Hwang,Seong‑Hoon Kang,Jeong Whan Yoon 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

Numerical modeling was conducted to investigate the deformation behavior of powder mixture during multi-pass drawingprocesses for multi-filamentary MgB2wire. A modified Drucker-Prager Cap (DPC) model with an elliptical cap surface usingthe new material characterization method was developed to capture the anisotropic hardening behavior and hydrostatic effectof the powder mixture. A number of uniaxial die compaction, cold isostatic pressing, diametrical compression, and uniaxialcompression tests were conducted using different powder densities to characterize the modified DPC model. A commercialfinite element software ABAQUS with a user subroutine was used to simulate the drawing of the MgB2wire. The densityand area fraction of the powder mixture during the wire-drawing process were verified with experimental results. The differencein packing density at the inner and outer filaments of the MgB2wire was successfully captured by simulation. Inaddition, the effect of the initial packing density on the superconducting properties of MgB2wire was numerically studied. It is shown that the increase in the superconducting area, which results from a high initial packing density, should be moreeffective compared to the increase in the grain connectivity in enhancing the critical current properties for the MgB2wirewhen the final packing density is saturated after a number of drawing processes.

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

급성신부전을 동반한 알콜성 횡문근융해증 2례

김영민,오동렬,이원재,김형국,황두영,이환,최경호,정시경,김세경,김영옥 大韓應急醫學會 1998 대한응급의학회지 Vol.9 No.4

Rhabdomyolysis is a biochemical and clinical syndrome caused by lysis of skeletal muscle cell and release of muscle cell contents into the circulation. In addition to traumatic cause, various nontraumatic causes have been reported. Rhabdomyolysis has frequently been associated with seamy aspects of life and society: alcoholic abuse, drug addiction, sadistic drill exercise, war events and attempted suicide. The abuse of alcohol causes many hazards in many organs. One of these is acute alcoholic myopathy that may present as a fulminent syndrome of muscle pain and tenderness associated with rhabdomyolysis and acute renal failure. Because the prognosis of adequately treated rhabdomyolysis is excellent, early recognition and prompt management are essential in emergency situation. We experienced two typical cases of alcohol-induced rhabdomyolysis with acute renal failure and report these cases with literature review.

대전시 노은 도매시장 채소류의 농약 잔류 실태 및 식이섭취량 추정

한국탁,이규승,이은경,이용재,고광용,원동준,이정원,권순덕 한국환경농학회 2003 한국환경농학회지 Vol.22 No.3

대전시 노은 도매시장에서 채취한 6종의 채소류 중 농약잔류량을 조사한 후 이에 대한 위해성 평가를 실시하였다. 전체 100건의 분석시료 중 농약이 검출된 시료의 비율은 46.0%이었고, 잔류허용기준 초과비율은 6.0% 이었다. 검출비율이 높은 시료는 상추(85.0%), 깻잎(80.0%), 오이(60.0%) 순이었고, 상추 3건, 깻잎 3건이 허용기준을 초과하였다. 살균제는 dicar-boximide계, 유기염소계, azole계 농약, 살충제는 유기인계, 합성 pyrethroid계 농약이 많이 검출되었다. 검출빈도가 높은 성분은 procymidone, chlorpyrifos, chlorothalonil, cypermethrin, EPN의 순이었다. 위해성을 평가하기 위해서 각 농작물에 대한 농약의 추정 섭취량과 ADI를 비교한 결과, 허용기준을 초과한 깻잎의 bitertanol, triflumizole, iprobenphos가 다른 성분에 비하여 높은 비율을 보였다. 그러나 각 농산물의 식이섭취량이 적어 ADI에 대한 추정섭취량의 비율이 0.46%이하로 나타나 그 영향이 매우 낮은 것으로 판단되었다. Pesticide residues in some vegetables collected at Noeun wholesale market in Daejeon were surveyed and assessed their risk In 100 samples, the detection rate of pesticide was 46.0% and the rate exceed MRL was 6.0%. Commodities showing high detection rate were lettuce(85.0%), perilla leaf(80.0%) and cucumber(60.0%). Dicarboximide, organochlorine, and azole fungicides and organophosphorus and pyrethroid insecticides were detected. Detection frequency of pesticide was in the order of procymidone, chlorpyrifos, chlerothalonil, cypermethrin and EPN. When the estimated intake amount of the pesticides were compared with ADI to assess their risk, bitertanol, triflumizole and iprobenphos in perilla leaf were higher rate than the other vegetables. However the total amounts of intake of pesticides were estimated to less than 0.46% of ADI.

흡연자와 비흡연자의 타액에서 코티닌 정량 및 ETS 노출량 평가

임흥빈,강영국,손형옥,이영구,문자영,이동욱 충북대학교 엽연초연구소 2001 煙草硏究 Vol.18 No.-

This study was conducted to measure and compare the salivary cotinine concentration between smokers and nonsmokers, and to investigate the effect on the exposure to environmental tobacco smoke(ETS) with housewives, living on an apartment of Korea. Saliva samples were taken from all volunteers and salivary cotinine was analyzed by a developed radioimmunoassay(RIA) method. The median salivary cotinine levels were 52.8±12.6 ng/ml and 44.6± 9.7 ng/ml in male smokers and in female ones, respectively, and they were 4.3±2.1 ng/ml and 2.9±3.1 ng/ml in male nonsmokers and in female ones, respectively. In addition, average salivary cotinine levels were 3.8±2.7 ng/ml in housewives from smoking homes and 2.4±2.4ng/ml in ones from nonsmoking homes. Results obtained from the analysis of salivary cotinine demonstrate that smokers had a significantly higher concentration of salivary cotinine than nonsmoker. But, there was no significant difference in the salivary cotinine concentration for housewives living in apartment between with smoking husband and with nonsmoking husband.

모 축전지 회사 근로자들의 연폭로 지표에 대한 경시적 관찰

강명식,김용배,이용진,리갑수,김화성,황규윤,장봉기,이성수,안규동,이병국 순천향대학교 산업의학연구소 1998 순천향산업의학 Vol.4 No.1

Lead poisoning is still prevalent and one of important occupational disease in Korea. To prevent undue high lead burden and maintain good health condition of lead workers in lead using industries, periodic health examination and regular biological monitoring of lead workers are often required in addition to the fundamental improvement of their working condition. To evaluate the effect of comprehensive occupational health program with regular biological monitoring on the level of lead exposure of lead workers in lead using industries, 11 year database from 1983 to 1994 of one storage battery factory was reviewed. From 1983 to end of 1986 only periodic health examination was provided to the lead workers, but from 1987 comprehensive occupational health program with regular biological monitoring was provided to maintain better health condition of lead workers. Selected study variables for lead exposure were blood lead(PbB), zinc protoporphyrin in blood(ZPP), δ-aminolevulinic acid in urine(ALAU), hemoglobin(Hb), hematocrit(HCT). Information on sex, age and work duration was also reviewed. 5 years data from 1983 to 1987 and 3 years data from 1990, 1993 and 1994 were available for all lead exposure indices except ALAU which has only 5 years data from 1983 to 1997. The results of 11 years longitudinal observation of lead indices are all follows: 1. The mean value of ZPP of lead workers in 1983 was 148.7±73.1 ㎍/㎗(Male: 145.5±72.3, Female: 168.1±79.1), whereas that of ZPP of lead workers in 1994 was decreased to 64.3±32.7 ㎍/㎗(Male: 60.2±28.8, Female: 95.2±43.4). 2. The mean value of PbB of lead workers in 1983 was 56.4±18.8 ㎍/㎗(Male: 55.59±19.1, Female: 59.6±19.1), whereas that of PbB of lead workers in 1994 was dcreased to 35.4±11.9 ㎍/㎗(Male: 35.7±12.0, Female: 32.8±10.8). 3. The mean value of Hb of lead workers in 1983 was 14.1±1.4 g/㎗(Male: 14.4±1.1, Female: 11.7±0.8), whereas that of Hb of lead workers in 1994 was increased to 15.6±1.5 g/㎗(Male: 15.9±1.2, Female: 12.9±1.1). 4. Blood lead is most highly correlated with ZPP(r=0.522, male:0.54 and female:0.50) and also correlated with ALAU and work duration also. 5. The simple regression analysis of PbB and ZPP showed different coefficient of regression by the measurement year, but there was no difference of coefficient of regression between sex. The slope of equation of pooled data for 1983-1986 without comprehensive occupational health program was 2.16 and differed from that of pooled data for 1987-1994(1.25). This difference suggests that the unit effect of blood lead on ZPP was relatively smaller in later period of comprehensive occupational health program than carly period without comprehensive program. The slope change in the analysis of linear regression of PbB on ZPP in lead workers can be used to evaluate the possible effect of health intervention to prevent undue high lead absorption in lead using industries. 6. 11 years occupational health service in this storage battery factory brought out considerable improvement of health status of lead workers in terms of decrease of PbB and ZPP and increase of Hb and the improvement was more remarkable after the introduction of comprehensive occupational health program.

65세 이상의 노령층에서 고지혈증의 위험요인

김용배,장원기,황보영,김화성,안규동,이병국,이용진,김세훈,김승수,김승훈,김영록,김웅빈,이성수 순천향의학연구소 2006 Journal of Soonchunhyang Medical Science Vol.12 No.1

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백서에서 수술 후 복부 유착방지용 재료들의 효능평가

심희수(Hee Soo Shim),이영우(Young Woo Lee1),이영무(Young Moo Lee),오영하(Young Ha Oh),권성원(Sung Won Kwon),김진홍(Jin Hong Kim),손승국(Seung Kook Sohn) 대한외과학회 2002 Annals of Surgical Treatment and Research(ASRT) Vol.63 No.3