• Title/Summary/Keyword: recognized hazard

검색결과 85건 처리시간 0.033초

Characteristics of Transmissible CTX-M- and CMY-Type β-Lactamase-Producing Escherichia coli Isolates Collected from Pig and Chicken Farms in South Korea

  • Shin, Seung Won;Jung, Myunghwan;Won, Ho Geun;Belaynehe, Kuastros Mekonnen;Yoon, In Joong;Yoo, Han Sang
    • Journal of Microbiology and Biotechnology
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    • 제27권9호
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    • pp.1716-1723
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    • 2017
  • The rapid dissemination of extended-spectrum ${\beta}$-lactamase (ESBL)-producing Escherichia coli has significantly contributed to public health hazard globally. A total of 281 E. coli strains recovered from pigs and chickens between 2009 and 2015 in South Korea were analyzed for ESBL production. ESBL phenotypes were recognized in 14 E. coli isolates; ten and three ESBL-producing isolates carried only $bla_{CTX-M}$ and $bla_{CMY}$ genes, respectively, and one isolate harbored both genes. The predominant CTX-M and CMY types were CTX-M-15 (n = 8) and CMY-2 (n = 3). We also detected ESBL-producing isolates harboring $bla_{CTX-M-65}$, $bla_{CTX-M-14}$, $bla_{CMY-6}$, $bla_{DHA-1}$, and $bla_{TEM-1}$ genes. All ESBL-producing isolates showed resistance to the extent of the fourth generation cephalosporins, along with multidrug resistance. CTX-M-15-producing isolates showed higher MIC values than CTX-M-14- and CTX-M-65-producing isolates. The $bla_{CTX-M}$ and $bla_{CMY}$ genes have the potential to be transferable. The spreading of $bla_{CMY}$ and $bla_{CTX-M}$ genes was arbitrated mainly via Frep and IncI1 plasmids. Our isolates showed clonal diversity in PFGE analysis. This is the first report of E. coli isolates carrying $bla_{CMY-6}$ in chicken from South Korea. The emergence of CMY-6 ESBLs in a population of poultry suggests that extensive screening with long-term surveillance is necessary to prevent the dissemination of ESBL from chicken to human.

주부의 식품안전에 대한 인식과 안전성우려의 관련 요인 (Consumer Perceptions of Food-Related Hazards and Correlates of Degree of Concerns about Food)

  • 최정숙;전혜경;황대용;남희정
    • 한국식품영양과학회지
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    • 제34권1호
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    • pp.66-74
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    • 2005
  • 전국의 대도시, 중소도시, 읍면지역의 주부 100명을 대상으로 구조화된 설문지를 이용하여 전화면접조사를 실시하였다. 식품안전에 대하여 불안을 느끼는 사람이 55.4%, 불안을 느끼지 않는 사람이 34.6%로 식품안전성에 대해 불안을 느끼는 사람의 비율이 1.9배 높은 것으로 나타났다. 식품안전에 대한 불안감에 영향을 미치는 요인은 유아나 초등학생의 자녀여부, 학력, 채소류 구입 장소, 브랜드, 보존료나 착색료 등의 식품첨가물, 원재료의 원산지 등이었다. 불안요인 중 잔류농약은 대상자의 96.0%가, 보존료나 착색료 등 식품첨가물 95.7%, 환경호르몬 93.0%, 식중독균 등 유해 미생물 91.7%, 유전가변형식품은 90.2%가 불안을 느끼는 것으로 나타났다. 그러나 실제로는 잔류농약이나 식품첨가물보다 미생물의 발생으로 인한 식품오염으로 나타날 수 있는 식중독의 경우 더욱 치명적일 수 있으므로 이러한 사실을 일반 소비자들에게 인식시킬 필요가 있다. 불안을 느끼는 식품으로, 도시락은 대상자의 93.3%가, 수입 식품은 92.7%, 패스트푸드 89.9%, 햄과 소시지 등 식육가공식품 88.7%, 외식(패스트푸드 이외의 식품) 81.6%, 통조림과 냉동식품 등 가공식품 83.5%, 컵라면 등 인스턴트식품 82.0%, 쌀 47.4%, 식용유 53.8%, 우유 및 유제품은 56.6%가 불안하다고 느꼈다. 식품의 제조(재배) 및 원료(원산지)를 제시해주는 식품표시에 대하여 신뢰하지 못하고 불안을 느끼는 대상자가 많으므로(75.2%) 표시 제도와 인증제도의 적절한 운용을 통해 식품에 관련한 충분한 정보가 소비자들에게 전달될 수 있는 대책이 강구되어야 하겠다. 신선식품(농축산물)구입시 가장 우려되며 우선적으로 고려하는 사항은 '수입산인지 국내산인지'이었으며 '유통기한', '무농약 및 유기재배 여부', '만질 때 혹은 외관상으로 느껴지는 신선함' 등이 그 다음으로 고려하는 것으로 나타났다. 가공식품 구입시에는 '보존료 및 착색료 등의 식품첨 가물'(93.6%), '유통기한'(92.4%), '원재료가 무농약$.$유기재배인지'(88.8%)에 대하여 염려된다고 응답한 비율이 높았다. 식품안전을 확보하기 위한 식품생산에서 소비단계까지 개선사항으로 '비료, 농약 살포, 수확시 관리 등 생산단계'(59.6%) 및 '물, 토양, 대기 등 자연환경'(43.6%)의 개선이 중요하다는 견해가 많았다. 위의 결과로 볼 때 식품안전성을 확보하기 위해서는 식품위생과 안전성, 식품표시에 대한 홍보와 교육이 지속적으로 이루어져 소비자들의 식품안전에 대한 인식과 신뢰도를 높여야 할 것이다. 농장단계에서 오염원을 줄이는 방안이 최종생산물의 검사에 기반을 둔 식품안전정책보다도 안전성 확보에 훨씬 유효하다는 사고방식이 보편화되고 있으므로 농산물 생산단계에 우수농산물관리 제도(good agricultural practices)를 정착시키고, 나아가 사전예방 원칙을 적용한 HACCP 시스템을 도입하여 식품(특히 축산물)의 안전성을 확보하여야 하겠다. 또 food chain 전반에 관한 이력정보의 부족과 정보의 신뢰성이 문제가 되므로 생산단계부터 가공단계, 유통단계, 그리고 판매 단계 에 이르기까지의 모든 과정을 소비자가 역으로 거슬러 올라가 확인할 수 있는 '이력정보체계 (traceability system)'를 활성화하여야 하겠다.

산지경사도(山地傾斜度) 및 3요소(要素) 시용수준(施用水準)이 초지토양(草地土壤) 및 목초중(牧草中) 무기양분(無機養分)의 상호균형(相互均衡)과 Grass Tetany 위험성(危險性)에 미치는 영향(影響) (Effects of Different Levels of Hilly Inclination and Nitrogen, Phosphorus and Potassium Application Rate on the Mutual Balances of Mineral Nutrients in Pasture Soils and Mixed Forages, and the Grass Tetany Hazard in a Mixed Grass-Clover Sward)

  • 정연규;이종열
    • 한국토양비료학회지
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    • 제19권3호
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    • pp.231-238
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    • 1986
  • 산지(山地)의 경사도(傾斜度)($10^{\circ}$, $20^{\circ}$, $30^{\circ}$) 및 3요소(要素) $N-P_2O_5-K_2O$ (0-0-0, 14-10-10, 28-25-25, 42-40-40kg/10a) 수준(水準)이 겉뿌림 산지초지(山地草地)(orchardgrass, tall fescue, redtop, ladino clover 혼파(混播))의 조성(造成), 생산성, 식생(植生) 및 목초품질등(牧草品質等)에 미치는 영향(影響)을 구명(究明)하였다. 본교(本橋)에서는 토양(土壤) 및 목초중(牧草中) 무기양분(無機養分)의 함량(含量) 및 상호비율(相互比率)을 grass tetany 발생위험성(發生危驗性)과 연관(聯關)하여 검토(檢討)하였다. 1. 토양중(土壤中) 치환성(置換性) Mg 함량(含量)이 낮고, CEC, K, Ca에 대한 Mg 비율(比率)이 부적합(不適合)하여 목초(牧草)의 정상생육(正常生育)에 불리(不利)하였고, tetany 발생(發生) 가능도(可能度)를 높여주는 조건(條件)이였다. 이는 경사도(傾斜度) 및 3요소시용수준(要素施用水準)이 증가(增加)된 토양(土壤)일수록 더욱 불량(不良)한 조건(條件)이 되었다. 2. tetany발생(發生)이 가능(可能)한 조건(條件)(목초중(牧草中) Mg 함량(含量) < 0.2%, K > 2.5%, K/(Ca+Mg)당량비(當量比) > 2.2)과 비교(比較)할때 Mg함량(含量)은 0.09~0.14%, 3요소(要素) 보비수준시(普肥水準時) K 함량(含量) 2.6% 및 K/Ca+Mg 당량비(當量比) 2.5를 보였다. 일반적(一般的)으로 경사도(傾斜度) 및 3요소(要素) 시용수준(施用水準)이 증가(增加)할수록 tetany 발생(發生) 위험성(危驗性)이 높아지는 불리(不利)한 지성(持性)을 나타내었다. 3. 산지초지(山地草地)의 토양(土壤) 및 목초중(牧草中) Mg 함량(含量) 및 염기간(鹽基間)의 상대비(相對比)가 목초생육(牧草生育) 뿐만 아니라 가축건강유지(家畜健康維持)에 부족(不足)한 수준(水準)이었으며 경사도(傾斜度) 및 3요소(要素) 시용수준(施用水準)이 증가(增加)할수록 Mg 시비(施肥)와 방목우(放牧牛)에 별도(別途)의 Mg 염(鹽)의 공급(供給)이 필요(必要)하였다. 4. 목초중(牧草中) Ca/P비율(比率)은 경사도별(傾斜度別) 차이(差異)는 없으나 3요소(要素) 시용수준(施用水準)이 증가(增加)할수록 낮아지며 그 범위(範圍)는 평균(平均) 1.0~2.0을 나타내었다.

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A Study on the Bobos Styles in the Contemporary Fashion Trend - Focusing on the Bobos feature in Korea -

  • Han, Gwi-Ja
    • 패션비즈니스
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    • 제8권3호
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    • pp.59-69
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    • 2004
  • This thesis has an intention to examine how much Bobos, which has appeared as a new ruling class in the age of digital information economy, has had an influence on the fashion design and which aspect Bobos fashion assumes specifically. The existence of Bobos in Korea and its cultural disposition are examined. To do so, questionnaire survey has been performed for 400 persons. According to the result, it is shown that they control themselves thoroughly through exercise and have much interest in their health; for example, they prefer organic agricultural products and nonpolluting foods. They also consume goods reasonably, emphasizing on their own individuality, rather than purchase high-price articles for no good reason, and enjoy their life while seeking for success in the society. Such a disposition is almost same as that in the U.S, showing a small difference in the occupation or origins. It is examined which aspect Bobos fashion design, a new trend, assumes in more detail. Bobos seeks for a thing that is not cheap, has a recognized brand, and is not behind the fashion. They like the nature friendly, classical, and not vulgar thing. design should be casual and practical, and the quality of the material should be good. Especially, an individual disposition is emphasized in Bobos fashion, in which they disregard a brand and try to be the subject of a trend, by creating a fashion by themselves, to express their originality freely. Bobos fashion the first style it harmonizes the appear things not to be matching with each other and depending on pursuing the mix & match. The second style of Bobos fashion nature is friendship and fight. The hazard which it does like that the fact that it attempts is the composition characteristic of idea. The namely design is an utility cheap assuredly with high-class characteristic of subject matter is not a recognize cheap. The third style of Bobos fashion is expressed in nostalgic about the art. Of course Bobos style is not a possibility fashion as main stream of doing still today, but the effect of Bobos is magnified gradually from cultural, social, economic area. It analyzes style is a tendency where trend of the consumer is gradually converted marketing. This paper is meaningful in the sense that Bobos class, which has not been examined yet systematically, and the fashion are connected closely, and the fashion trend in the next is examined.

터널 입구부 대절토 사면 안정성 사례 연구 (Case Study of the Stability of a Large Cut-Slope at a Tunnel Portal)

  • 박동순;배종섬
    • 지질공학
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    • 제25권1호
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    • pp.115-129
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    • 2015
  • 대단면 터널 입구부의 대절토 사면은 불안정한 응력분포 및 소성변형 가능성으로 인해 잠재적 취약부로 인식되고 있다. 본 사례연구에는 대단면 터널 갱구부 대절토 사면의 강우 후 유실사고 및 원인규명, 복구공법을 분석하여 제시하였다. 대상 현장은 46 mm의 강우 후 암반의 불연속면을 따라 대규모 평면파괴가 발생하였으며, 상부 절토사면의 불안정을 야기하였다. 지질조사 및 매핑 자료 분석 결과, 붕괴 원인은 풍화된 암반의 불연속면에 협재된 충전물과 지반 포화로 인한 절리면 연화(softening)로 판단되었다. 알칼리 장석이 풍부한 화강편마암은 풍화에 취약한 것으로 나타났다. 침하량 계측자료 분석 결과, 붕괴 직전에 급격한 변위량 증가를 관찰하였으며, 향후 사면 계측관리에 활용할 수 있을 것으로 판단된다. 응급복구 대책으로 콘크리트 공동충전 및 외부로부터 압성토 채움을 성공적으로 시행하였다. 항구복구 대책으로 사면부에는 격자블럭 및 지중 앵커 시스템을, 터널 측벽부에는 추가 락볼트 보강 및 그라우팅 공법을 성공적으로 적용하였다. 한계평형해석과 평사투영해석을 통해 원 사면의 불안정성과 보강방법의 유효성을 확인하였다. 본 사례연구는 향후 유사한 대절토 사면에 귀중한 참고자료로 활용될 것으로 기대된다.

Comparative Outcome of Thai Pediatric Osteosarcoma Treated with Two Protocols: the Role of High-Dose Methotrexate (HDMTX) in a Single Institute Experience

  • Choeyprasert, Worawut;Pakakasama, Samart;Sirachainan, Nongnuch;Songdej, Duantida;Chuansumrit, Ampaiwan;Anurathapan, Usanarat;Hongeng, Suradej;Nartthanarung, Adisak
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권22호
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    • pp.9823-9829
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    • 2014
  • Background: High-dose methotrexate (HD-MTX) is recognized as an efficient component of therapy against pediatric osteosarcoma in combination with other drugs such as cisplatin (CDP), carboplatin (CBDCA), doxorubicin (ADM), etoposide (VP-16) and ifosfamide (IFO). Objectives: To demonstrate the feasibility and effectiveness of the HD-MTX/CDP/DOX/VP-16/IFO [MTX(+)] protocol comparable to CDP/ADM/CBDCA/IFO [MTX(-)] for treating childhood osteosarcoma at Ramathibodi Hospital (1999-2014). Materials and Methods: A retrospective analysis was conducted of osteosarcoma patients aged less than 18 years treated with two chemotherapeutic regimens between 1999 and 2014. A total of 45 patients received the MTX(-) and 21 the MTX(+) protocol. Results: Overall limb-salvage and amputation rate were 12.9% and 77.7%, respectively. Kaplan-Meier analysis results for 3-year disease free survival (DFS) and overall survival (OS) regardless of treatment regimens were $43.4{\pm}6.0%$ and $53.2{\pm}6.1%$ respectively. The 3-year DFS and OS were improved significantly with the MTX(+) protocol compared to MTX(-) protocol (p=0.010 and p=0.009, log rank test) [$69.8{\pm}10.5%$, $79.8{\pm}9.1%$ for MTX(+) and $31.1{\pm}6.9%$, $42.2{\pm}7.4%$ for MTX(-) protocol, respectively]. Patients with metastatic osteosarcoma treated with the MTX(+) protocol had statistically significant higher 3-year DFS and OS than those treated with the MTX(-) protocol ($66.7{\pm}13.6%$ and $15.0{\pm}8.0%$ for 3-year DFS, p=0.010, $73.3{\pm}13.2%$ and $20{\pm}8.9%$ for 3-year OS, p=0.006, respectively). The independent risk factors for having inferior 3-year DFS and OS were poor histological response (tumor necrosis <90%) and treatment with the MTX(-) protocol. The multivariate analysis identified only the treatment with the MTX(-) protocol as an independent predictor of inferior OS with a hazard ratio (HR) of 3.53 (95% confidence interval of 1.2-10.41, p=0.022). Conclusions: Our study demonstrated the tolerability, feasibility and efficacy of the HDMTX-based regimen improving the survival rate in pediatric osteosarcoma cases, in line with reports from developed countries.

Elevated Platelets Enhance Cancer Cell Migration, Promote Hematogenous Metastasis and Associate with a Poor Prognosis in Advanced Non-small Cell Lung Cancer Cases

  • Li, Yan;Miao, Li-Yun;Xiao, Yong-Long;Cai, Hou-Rong;Zhang, De-Ping
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권1호
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    • pp.139-143
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    • 2014
  • Although correlations between platelets and lung cancer has been recognized, effects on non-small cell lung cancer (NSCLC) metastasis remain to be determined in detail. In the present study, wound healing assays revealed a role of platelets in NSCLC cell migration. Thus the mean migration rate of lung adenocarcinoma A549 cells was significantly elevated after co-culture with platelets ($81.7{\pm}0.45%$ vs $41.0{\pm}3.50%$, P<0.01). Expression of GAPDH was examined by reverse transcription-polymerase chain reaction to study the effect of platelets on NSCLC cell proliferation. The result showed that the proliferation of A549 and SPC-A1 cells was not affected. Mouse models were established by transfusing A549 cells and SPC-A1 cells into mice lateral tail veins. We found tumor metastasis nodules in lungs to be increased significantly after co-transfusion with platelets (in A549, $4.33{\pm}0.33$ vs $0.33{\pm}0.33$, P=0.01; in SPC-A1, $2.67{\pm}0.33$ vs $0.00{\pm}0.00$, P=0.01). In addition, consecutive inoperable patients with newly diagnosed NSCLC (TNM stage III or IV) between January 2009 and December 2011 were retrospectively reviewed. Using the Kaplan-Meier method, NSCLC patients with a high platelet counts demonstrated a significantly shorter progression free survival compared with those with a low platelet count (> $200{\times}10^9/L$, 3 months versus ${\leq}200{\times}10^9/L$, 5 months, P=0.001). An elevated platelet count was also identified as an independent prognostic factor by Cox regression analysis for prgression free survival (adjusted hazard ratio: 1.69; 95% CI: 1.16, 2.46; P=0.006). This study suggested that platelets might contribute to the hematogenous metastatic process by promoting cancer cell migration, which eventually affects the prognosis of NSCLC.

Hypoxia Induced High Expression of Thioredoxin Interacting Protein (TXNIP) in Non-small Cell Lung Cancer and its Prognostic Effect

  • Li, Yan;Miao, Li-Yun;Xiao, Yong-Long;Huang, Mei;Yu, Min;Meng, Kui;Cai, Hou-Rong
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권7호
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    • pp.2953-2958
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    • 2015
  • Although associations between thioredoxin interacting protein (TXNIP) and cancers have been recognized, the effects of TXNIP on non-small cell lung cancer (NSCLC) prognosis remained to be determined in detail. In addition, while hypoxia is a key characteristic of tumor cell growth microenvironment, the effect of hypoxia on TXNIP expression is controversial. In this study, formaldehyde fixed and paraffin embedded (FFPE) samples of 70 NSCLC patients who underwent resection between January 2010 and December 2011 were obtained. Evaluation of TXNIP and hypoxia inducible factor-$1{\alpha}$ ($HIF-1{\alpha}$) protein expression in FFPE samples was made by immunohistochemistry. By Kaplan-Meier method, patients with high TXNIP expression demonstrated a significantly shorter progression free survival (PFS) compared with those with low TXNIP expression (18.0 months, 95%CI: 11.7, 24.3 versus 23.0 months, 95%CI: 17.6, 28.4, P=0.02). High TXNIP expression level was also identified as an independent prognostic factor by Cox regression analysis (adjusted hazard ratio: 2.46; 95%CI: 1.08, 5.56; P=0.03). Furthermore, TXNIP expression was found to be significantly correlated with $HIF-1{\alpha}$ expression (Spearman correlation=0.67, P=0.000). To further confirm correlations, we established a tumor cell hypoxic culture model. Expression of TXNIP was up-regulated in all three NSCLC cell lines (A549, SPC-A1, and H1299) under hypoxic conditions. This study suggests that hypoxia induces increased TXNIP expression in NSCLC and high TXNIP expression could be a poor prognostic marker.

알리인 투여 후 혈소판의 방사선 방어기전 연구 (A Study on Radio-Protection Mechanism of Platelet Cells After Injection of Alliin)

  • 지태정
    • 대한방사선기술학회지:방사선기술과학
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    • 제33권3호
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    • pp.185-192
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    • 2010
  • 거대핵세포(megakaryocyte)에서 유래된 혈소판은 백혈구와 더불어 방사선에 민감하여 가장 먼저 감소하므로 방사선장해의 지표로 활용된다. 따라서 혈소판이 부족하게 되면 점상출혈(dot hemorrhage)이 계속되고 혈구 수의 감소와 면역기능 저하로 이어진다. 특히, 전신조사(whole body irradiation)로 4~6 Gy를 받을 경우, 3주 후 혈소판이 최하로 감소되어 출혈과 빈혈에 의한 조혈기계 장해의 사망원인이 된다. 따라서 본 연구는 혈소판 장해의 메카니즘을 밝히고 방어효과를 알아보고자 하였다. 실험에 사용한 방어물질은 마늘 성분의 알리인(Alliin)을 사용하였으며, rat의 꼬리 정맥에 투여한 후 전자현미경(TEM)으로 관찰하였다. 연구 결과, 5 Gy 방사선조사(Irradiation) 후 10일 경과된 혈소판 조직에서는 세포막이 심하게 손상되어 풍선모양으로 부풀어 올랐으며, 당질층(glycocalyx)이 비후되었다. 조사 후 20일 경과된 혈소판에서는 소기관들의 형태를 알아볼 수 없을 정도로 손상되었으며, 세포질의 내용물이 간질부위로 유출되어 손상이 매우 심하였다. 또한 과립들의 형태도 관찰되지 않았다. 30일 경과된 혈소판에서는 가운데 부분에서 공포(vacuole)가 생기고 조직의 손상이 관찰되었다. 하지만 Alliin을 정맥 투여한 실험군에서는 과립(granules)들의 형태가 대조군과 같이 일정하게 유지되고 있었으며, 세포막의 손상도 확인되지 않았다. 따라서 Alliin의 혈관투여시 혈소판의 방사선방어 효과를 확인할 수 있었다.

기계소(機械騷) 음(音)과 회전(回轉) 속도(速度) (An Effect of Revolutions Per Minute (r.p.m) in the Noise Characteristics)

  • 차봉석
    • Journal of Preventive Medicine and Public Health
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    • 제10권1호
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    • pp.94-101
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    • 1977
  • Noise pollution, both in the environment and in the workplace, has been recognized as a major health hazard -one that can impair not only a person's hearing but also his physical and mental well-being. As industrialization progresses, the prevalence rate of occupational diseases is increasing, especially hearing loss, which has the highest prevalence rate among the occupational diseases. The major cause of noise is the construction of various large industries without any regulation of noise sources. Therefor, we must establish an enactment to control mechanical noise sources. as soon as possible. For the purpose of controlling the noise source, we must have exact data about such things as the sound level, the frequency of the peak sound and the revolutions per minute (r.p.m.) of the machine (a measure of the power of its motor). This study was undertaken in order to define the noise characteristics, the power of the machine's motor, the change of the sound level and the peak sound as the r.p.m. increases, and the permissible exposure time. The sample size of this study was 74 machines at 11 plants in 6 industries. The results are as follows; 1. The breakdown of the types of mechanical noise noted was : 63.6% continuous normal sound, 26.9% intermittent sound, 4.7% continuous repeating sound and 4.6% impulsive sound. 2. With respect to the type of industry, the overall sound level was the highest in the mechanical industry, with $103.8{\pm}2.8dB(A)$, and lowest in the textile industry, with $89.2{\pm}1.43dB(A)$. 3. With respect to the type of machine, the highest sound level was 124 dB(A) caused by Gauzing(II), in the mechanical industry, and the lowest was 76 dB(A) caused by Attachment (Jup Chack) (I) in the timber industry. 4. The shortest permissible exposure time to Gauzing(II) in the mechanical industry was less than 15 minutes. 5. Among 74 machines, 68.2% of the peak sound was situated in the high frequency range (52.7% at 2 KHz, 4.1% at 4 KHz and 1.4% at 8 KHz). 41.8% of the peak sound was in the middle frequency range (4.1% at 250Hz, 14.8% at 500Hz and 22.9% at 1KHz). 6. If one machine had two motors or more, the peak sound was shifted to the low frequency range. 7. As the r.p.m. increased, the overall and peak sound levels were increased without any change of the frequency of the peak sound. 8. Whenever the machines had the same kind and the same r.p.m., the overall and peak sounds were changed by the physicochemical characteristics of the raw materials and the management.

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