• 제목/요약/키워드: Lethal rate

검색결과 201건 처리시간 0.028초

Radioresistance of Acorus calamus to Gamma Ray Irradiation

  • Lee, Ja-Hyun;Kang, Si-Yong;Lee, Geung-Joo;Lee, Seong-Gene;Kim, Sun-Kook;Han, Tae-Ho
    • 화훼연구
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    • 제19권2호
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    • pp.119-125
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    • 2011
  • 창포는 한국에 자생하는 수생식물로 약용뿐만 아니라 phytoremediation과 수질정화 식물로도 알려져 있다. 본 연구에서는 창포의 기내 식물체에 다양한 선량(20-500 Gy)의 감마선을 조사하여, 방사선의 효과 및 감수성을 확인하기 위해 2달후 생존율, 신초형성율 및 생장율을 측정하였다. 생존율과 신초형성율은 감마선 선량이 증가할수록 현저하게 감소하였다. 기내에서 저선량을 조사한 식물체의 생장율은 대조구에 비해 오히려 증가하였으나, 250 Gy 이상에서는 생장이 멈추거나 유의하게 감소하였으며, 반치사선량($LD_{50}$)은 240 Gy로 다른 식물종의 $LD_{50}$보다 훨씬 높은 선량이었다. 창포에서 저선량을 조사하였을 때 생장율이 증가하는 방사선호메시스(radiation hormesis) 효과를 확인하였다.

Systematic review of self-assembling peptides as topical agents for treatment and prevention of gastrointestinal bleeding

  • Andrei Voiosu;Monica State;Victor Dragan;Sergiu Vaduva;Paul Balanescu;Radu Bogdan Mateescu;Theodor Voiosu
    • Clinical Endoscopy
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    • 제57권4호
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    • pp.454-465
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    • 2024
  • Background/Aims: Gastrointestinal bleeding is a significant and potentially lethal event. We aimed to review the efficiency and safety of self-assembling peptides for the treatment and prevention of gastrointestinal tract bleeding. Methods: We conducted a systematic search for studies describing the endoscopic use of self-assembling peptides for treatment or prevention of bleeding in the gastrointestinal tract in a parallel, independent fashion. The primary outcomes were rates of successful initial hemostasis, delayed bleeding, and rebleeding. The secondary outcomes were adverse events and ease and volume of gel used. Results: Seventeen studies were analyzed. Overall success rate of self-assembling peptides in gastrointestinal bleeding was 87.7% (38%-100%), regardless of etiology or associated treatments. Rebleeding rate ranged from 0% to 16.2%, with a mean of 4.7%, and overall delayed bleeding rate was 5% (range, 0%-15.9%). Only three adverse events were reported in a pooled number of 815 patients. The volume of gel used varied (0.43 to 3.7 mL) according to indication and type of bleeding. Conclusions: The limited available data on the use of self-assembling peptides in gastrointestinal endoscopy suggest a high efficiency and good safety profile.

평형기의 Vero세포계에서 방사선($\gamma$-선) 조사 후 발생한 잠재치사 손상의 회복에 관한 연구 (A Study on Recovery from Potentially Lethal Damage Induced by $\gamma-Irradiation$ in Plateau-phase Vero Cells in vitro)

  • 김일한;최은경;하성환;박찬일;차창룡
    • Radiation Oncology Journal
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    • 제6권1호
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    • pp.1-11
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    • 1988
  • 방사선 조사 후 발생한 잠재치사손상의 회복(PLDR)에 있어 조사선량 및 시간에 따른 환경변화가 회복의 동적양상에 미치는 영향을 Vero 세포계를 이용하여 실험하였다. 배양액을 교환시키지 않고 배양하여 평형기에 도달한 세포에 동물실험용 세시움 조사기로 $1Gy\~9Gy$의 감마선을 조사하고 각 조사조건에서 $O\~6$ 및 24시간동안 정치시킨 후 Agarose가 포함된 새로운 배양액에서 배양하였다. 16Gy를 조사한 동종의 세포를 feeder세포로 첨가하여 배양액내의 전 체세포수를 일정하게 한 조건에서 형성된 세포집락수에 따라 세포의 생존을 정하였다. 잠재치사손상의 회복은 $2\~4$시간 정치후에 포화수준에 도달한 빠른 회복이었다. 방사선량이 증가함에 따라 회복속도는 증가하였고, 포화수준의 회복량도 증가하였다. Linear-quadratic mode에 의한 "방사선량-생존분획" 분석 결과 잠채치사손상이 회복됨에 따라 일차 비활성계수 $\alpha$는 급속히 감소하여 $\beta$에 접근하였고 이차 비활성계수 $\beta$는 미미하게 증가하여 PLDR은 $\alpha$로 표시되는 손상에 주로 영향을 주었다. Multitarget model에 따라 분석한 결과 Do는 변화가 없고 Dq가 증가하였다. 세포 생존분획 이 높은 3Gy 이하의 저선량 영역에서 dose modifying factor가 높아 잠재 치사손상의 회복에 의한 영향이 저선량 영역에서 상대적으로 크게 나타났다.

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한국산 재래식 발효메주의 안전성에 관한 연구 (A Study on the Safety of Korean Domestic Fermented Meju)

  • 서화중;정두례
    • 한국식품영양과학회지
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    • 제20권1호
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    • pp.13-20
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    • 1991
  • For this experiment frist the fermented Soybean Meju was prepared by domestic ordinary method of Korean and concentrated Meju suspensoidal extract was made for toxicological test sample on mice and rat. Even the oral dose of 10g extract per kg of mice had not any acute toxicity. So the median lethal dose(LOD50) is lilely to be much greatr or not to be. In comparison of the average weight gain rate for 4 weeks the control and test groups of 0.308g Ex/rat kg and 9.24g Ex/rat kg daily were the much the same as about 19% but 3.08g Ex/rat kg group waas exceptionally 2.7% higher than control For this period all test groups did not show any abnormality in appearance and anatomic findings. In serum GPT GOT alkaline phosphatase and blood urea nitrogen value there were no difference significantly between control and the test groups of 0.308g/rat kg and 3.08g/rat kg but 9.24g/rat kg group was some what higher than control. Especially in cholesterol alkaline phosphatase and blood urea nitrogen value 9.24g/rat kg group or 28days had 100mg/이 37.5u 32mg/이 respectively which were increased significantly. The pathological findings of all test groups especially 9.24g/kg group did not showed any characterized sign of acute or subacute liver damage or intestine lesion. So it is supposed that there is not any tocixants originated from some molds in fermented Korean domestic Meju which is prepared traditionally in winter.

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시안화물 중독 후 해독제로 치료된 2례 (Treatment with the Taylor Cyanide Antidote Package after Cyanide Poisoning: Case Report)

  • 조범규;최한주;장용수;신태용;이강현;황성오;김현
    • 대한임상독성학회지
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    • 제5권1호
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    • pp.57-60
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    • 2007
  • Cyanide has been well known from antiquity. Cyanide poisoning causes histotoxic hypoxia--inhibition of mitochondrial cytochrome oxidase with disruption of the ability of cells to use oxygen. The mortality rate is 95% within 30 minutes. Acute cyanide poisoning is mostly the result of attempted suicide, and because of the high doses typically employed it usually is lethal within minutes. Also acute cyanide poisoning leads to a very poor prognosis because medical personnel can't detect cyanide intoxication and so many hospital haven't antidote. We report two cases of cyanide poisoning which responded well to treatment with the Taylor cyanide antidote package.

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Strain Improvement of Yeast for Ethanol Production Using a Combined Treatment of Electric Field and Chemical Mutagen N-Methyl-N'-nitro-N- nitrosoguanidine

  • Kim, Keun;Lee, Jae-Yeon
    • Journal of Microbiology and Biotechnology
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    • 제8권2호
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    • pp.119-123
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    • 1998
  • The feasibility of using combined treatments of electric field and chemical mutagen N-methyl-N'-nitro-N-nitroso-guanidine (NTG) for the strain improvement of Saccharomyces sp. in ethanol production was examined. The treatment of electric field alone resulted in no effect on the lethality of yeast cells under the conditions of this study. However, when the electric field was applied together to the treatment of yeast cells with NTG, the electric field increased the lethal effect and auxotrophic mutation rate of NTG. The combined treatment of electric field and NTG also increased the chances of. obtaining superior yeast strains for the ethanol production from tapioca. A higher number of improved clones was obtained by the combined treatments of electric field and NTG than by the NTG treatment alone. The best clone, NF 30-9, which was also obtained by the combined treatment, produced $11.07\%$ (w/v) ethanol from tapioca slurry containing 25% (w/v) reducing sugar while the parental strain produced 9.77% (w/v).

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Listeria Species in Broiler Poultry Farms: Potential Public Health Hazards

  • Dahshan, Hesham;Merwad, Abdallah Mohamed Amin;Mohamed, Taisir Saber
    • Journal of Microbiology and Biotechnology
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    • 제26권9호
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    • pp.1551-1556
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    • 2016
  • Broiler meat production worldwide has been plagued by lethal food-poisoning bacteria diseases, including listeriosis. A fatality rate of 15.6% was recorded in human beings in the EU in 2015. During 2013, a total of 200 poultry farm samples, including litter, chicken breast, farm feed, and drinking water, were collected to generate baseline data for the characterization of the genus Listeria in broiler poultry farms. Listeria spp. were detected in a total of 95 (47.5%) poultry farm samples. The isolates of Listeria spp. included L. innocua (28.5%), L. ivanovii (12.5%), L. welshimeri (4.5%), and L. monocytogenes and L. seeligeri (1% each). Listeria spp. contamination rates were higher in farm feed (70%), followed by litter (52.5%), chicken breasts (42.2%), and drinking water (10%). Almost all Listeria spp. isolates were resistant to more than three classes of antibiotics (multidrug resistant). Besides this, we observed a significant resistance level to penicillin and fluoroquinolone drugs. However, lower resistance levels were recorded for broad-spectrum cephalosporins. The inlA, inlC, and inlJ virulence genes were detected in almost all of the L. monocytogenes isolates. Thus, food safety management approaches and interventions at all stages of the broiler rearing cycle were needed to control cross-contamination and the zoonotic potential of listeriosis.

한국에서 분리된 렙토스피라균의 생물학적 특성에 대한 연구(1985) (Isolation and Characterization of Leptospira Interrogans in Korea, 1985)

  • 박경석;오희복;이명숙;성언근;박미연;이용우;김호훈;백승복
    • 대한미생물학회지
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    • 제21권3호
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    • pp.331-336
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    • 1986
  • A microbiological study for the isolation and characterization of Leptospira interrogans was performed in an attempt to define the characteristics of Leptospirosis in Korea. The results are summerised as follows. Thirty-five cultures were isolated from 11 patients with leptospirosis and 24 wild rodents captured in Paju area. The isolation rate of Leptospira from wild rodents reached 23.1%. All 35 cultures were identified as Leptospira interrogans by their characteristic morphology and motility in dark field microscopy, pathogenecity in Guinea pig and sensitivity to 8-Azaguanine. Cultures formed diffuse subsurface colonies with hazy margin and were catalase, peroxidase and oxdase positive. The fifty percent lethal dose of isolate HM 4 in Guinea pig was $8.9{\times}10^4$ org. Mouse passage method was sucecssfully applied in maintenance of fresh isolates without any loss of their original virulency.

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탄화수소 누출로 인한 위험분석 평가 방법론 연구 (A Methodology for Assessing Risk from Released Hydrocarbon)

  • Keun-Won Lee
    • 한국안전학회지
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    • 제13권2호
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    • pp.170-180
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    • 1998
  • 본 연구는 밀폐된 지역에서 경험적 증발속도식을 사용하여 누출된 탄화수소의 농도 계산방법을 소개하였다. 그 접근방법은 가정된 조건하에서 공기중의 탄화수소 누출 농도를 추정하여 노출된 근로자나 사람의 개인적 위험평가를 위해 probit 표현식에 의한 위험평가 방법론을 제시하였다. 벤젠-공기 및 톨루엔-공기계에 대해 독성기준과 사람의 노출데이타가 조사되어졌고, 위험평가를 위한 가이드라인를 제시하였다. 탄화수소와 비독성 물질의 혼합물의 치사농도의 몰분율에 다른 probit 상수값들을 예측하였다. 몰분율에 따라 계산된 probit값은 밀폐된 작업구간에서 독성을 예방하기 위한 가이드라인을 추정하기 위해 사용될 수 있다.

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64채널 심장전기도 시스템 구현에 관한 연구 (64 channels computerized cardiac mapping system)

  • 장병철;김남현
    • 대한의용생체공학회:의공학회지
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    • 제16권1호
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    • pp.107-113
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    • 1995
  • It is well known that multipoint and computerized intraoperative mapping systems improve the results of surgery for Wolff-Parkinson-White syndrome and show tremendous potential for opening an entirely new era of surgical intervention for the more common and lethal types of supraventricular tachyarrhythmias such as atrial flutter and atrial fibrillation. In addition, the ability to map and ablate the sometimes fleeting automatic atrial tachycardia is greatly enhanced by computerized mapping systems. In this study, we have developed 64 channel computerized data analysis system using microcomputer (Macintosh ${II}_{x}$) for basic research of electrophysiology and electrical propagation. The bipolar electrogram information is acquired from 64 cardiac sites simultaneously at a sampling rate of 1 ksampls/sec with continuous and total data storage of up to 30 seconds. When the reference electrogram is selected and reference point is picked up, delay time from the reference point is displayed on two dimensional diagram of the heart. System design permits easy expansion to almost 256 simultaneous sites. this system is expected to enable us to study pathophysiology of cardiac arrhythmia and to improve the result of diagnosis and surgical treatment for cardiac arrhythmia.

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