• 제목/요약/키워드: Harmful Effects

검색결과 994건 처리시간 0.033초

지황과 황기의 화학적 잡초 방제 (Chemical Weed Control in Rehmannia glutinosa and Astragalus membranaceus)

  • 김영국;방진기;유홍섭;성낙술
    • 한국약용작물학회지
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    • 제6권3호
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    • pp.221-226
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    • 1998
  • 지황과 황기의 적합한 제초제를 선발하여 제초의 생력화를 향상코자 지황에 5약제를 처리 하고 황기에 7약제를 공시하여 시험한 결과를 요약하면 다음과 같다. 1. 지황의 약효시험에서 경엽처리제인 Paraquat는 다년생 잡초의 방제가가 매우 높았다. 2. 정식후 토양처리형 제초제인 Napropamide와 Linuron도 약해 피해 없이 제초 효과가 있었다. 3. 지황 수량은 손제초구의 509kg/10a에 비해 Paraquat 처리구(524kg)에서 3% 증가하였으며, Napropamide, Linuron 처리구는 101%, 94% 수준이었다. 4. 황기는 파종후 토양처리형 제초제인 Nafropamide구에서 약해증상이 나타나지 않았고 1년생 잡초의 제초효과는 87%이었다. 5. Ethalfluralin과 Metolachlor은 제초효과는 높았지만 발아후 초기 생육시 생육지연 현상이 나타났다. 6. 황기 수량은 약해가 발생하지 않은 Napropamide 처리구가 양호하여 대비구의 129kg/10a 대비 98% 수준이었다.

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미나리발효액이 장내 유해세균 및 유익균의 In Vitro 생육 및 효소활성에 미치는 영향 (Effect of Extract of Fermented Dropwort on Intestinal Bacteria and Enzymes In Vitro)

  • 이경애;김무성;조홍범
    • 미생물학회지
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    • 제44권4호
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    • pp.358-361
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    • 2008
  • 미나리(Oenanthe stolonifera) 발효액이 장내 병원성 미생물과 유익균의 생육, 그리고 장내 세균효소에 미치는 영향을 in vitro 에서 조사하였다. 고상 배지 (Agar plate) 에서의 clear zone 형성에 의한 생육저해를 측정한 결과, Vibro, Salmonella 등의 유해 미생물에 대해서 강한 생육저해 효과를 보였으며 Bifidobacterium longum 에 대해서는 생육저해 효과가 크지 않았다. 액체배지에서의 최소저해농도(MIC) 측정에서도 고장배지에서와 같은 경향을 보여 상대적으로 B. longum 에 대한 생육저해가 가장 적었다. 발효 기간에 따른 영향을 보면 발효 기간이 길수록 적은 양으로도 유해한 균들의 생육을 잘 저해할 수 있는 것으로 나타났다. 장내 세균 효소인 ${\beta}$-glucuronidase와 tryptophanase의 활성에 대해 미나리 발효액은 발효하지 않은 액에 비해 저해효과가 컸으며 발효기간이 길수록 저해효과도 증가하였다. 이상의 실험 결과로서 미나리 발효액은 유해세균에 대한 생육저해능이 크고 상대적으로 유익균인 B. longum에 대한 저해는 적어, 음용 시 정장 효과가 있을 것으로 추정된다.

생쥐 난자의 체외 성숙에 미치는 Nicotine의 영향 (The Effects of Nicotine on the Mouse Oocyte Maturation In vitro)

  • 성기청;배인하
    • Clinical and Experimental Reproductive Medicine
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    • 제28권1호
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    • pp.1-12
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    • 2001
  • Objective: The present study was done to clarify the effects of nicotine and nicotine tartrate on the mouse oocyte maturation in vitro. Methods: GV (germinal vesicle) oocytes were isolated from Graafian follicle of ovaries with sharp needles under a stereomicroscope from female mouse of ICR strain (4 weeks old). Collected oocytes were cultured for 17 hours at $37^{\circ}C$, 5% $CO_2$ in air and 100% humidified condition in incubator. New MHBS was the basic medium used in which nicotine, nicotine tartrate, and mecamylamine (antagonist of nicotinic acetylcholine receptor) were added depending on the experimental group. GV oocytes were cultured in one of these media. Results: Nicotine ($300{\mu}M{\sim}5mM$) had no effects on GVBD (germinal vesicle breakdown) compared to the control, but increasing concentration of nicotine led to an decrease in the first polar body formation. However, nicotine ($10{\sim}500{\mu}M$) induced GVBD in a dose-dependent manner of GV oocytes in a medium containing dbcAMP. Nicotine tartrate ($50{\mu}M{\sim}5mM$) had no effects on GVBD compared to the control but, increasing concentration of nicotine tartrate led to an decrease in the first polar body formation. Mecamylamine $10{\mu}M$ added to the medium containing nicotine ($300{\mu}M{\sim}5mM$) showed higher percentage of the first polar body formation compared to the nicotine ($300{\mu}M{\sim}5mM$) treatment group. Mecamylamine $10{\mu}M$ added to the medium containing nicotine tartrate ($50{\mu}M{\sim}5mM$) showed higher percentage of the first polar body formation compared to the nicotine tartrate ($50{\mu}M{\sim}5mM$) treatment group. Conclusion: The present study suggest that nicotine and nicotine tartrate have the harmful effects on the meiotic maturation of the mouse oocytes in vitro. However, mecamylamine block harmful effects of nicotine and nictine tartrate.

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일부 성인의 간접흡연에 대한 인식도 및 대책 (The Awareness and Countermeasures against Harmful Effect of Passive Smoking in Korean Adult)

  • 심홍석;홍현숙;맹광호;이강숙
    • Journal of Preventive Medicine and Public Health
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    • 제33권1호
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    • pp.91-98
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    • 2000
  • Objectives : This study is to evaluate the awareness, attitude, practice and the countermeasures against passive smoking in Korean adults. Methods : By self-administered questionnaires, we assessed the knowledge, attitude, behavior for passive smoking and the countermeasure for reduction of it's harmful effects in 289 men and 238 women. Results : The subjects that have heard about passive smoking were 96.8% in total and well known were 26.4% of current smoker, 56.6% of ex-smoker, and 14.8% of non-smoker(p=0.001). The irritative symptom from passive smoking was the most frequent in non-smokers and the most common place where exposed to passive smoking was public place. For attitude against passive smoking in 'no smoking allowed area', ex-smokers were the most active to recommend to stop smoking. And for opinion about establishment of 'no smoking allowed area', the restriction by law was the best acceptable method in smokers, exsmokers, and nonsmokers. In marking of 'no smoking allowed area', 69.9% of smokers answered no smoking, but in non-marking area only 6.3% stop smoking. When smokers were recommended to stop smoking, the more subjects stop smoking with good feeling in marking area, but the less in non-marking area. The factor associated the high awareness of passive smoking were aged(OR=1.07, 1.03-1.12), men(OR=4.34, 2.32-8.46). The persons who have known well about passive smoking had good attitude and behavior to prevent of harmful effect of passive smoking. Conclusions : This study suggested that education program would be necessary to reduce the passive smoking.

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Photodynamic Action by Endogenous Non-Chlorophyll Sensitizer As a Cause of Photoinhibition

  • Suh, Hwa-Jin;Kim, Chang-Sook;Jin Jung
    • Journal of Photoscience
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    • 제7권3호
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    • pp.87-95
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    • 2000
  • As sunlight not always optimized for every terrestrial plant in terms of light quality, quantity and duration, some plants suffer detrimental effects of sunlight exposure under certain conditions. Photoinhibition of photosynthesis is a typical phenomenon representing harmful light effects, commonly observed in many photosynthetic organisms. It is generally accepted that functional, structural loss of photosystem II complex(PSII) is the primary event of photoinhibition. Accumulating data also suggest that singlet oxygen($^1$O$_2$) is the main toxic species directly involved in it. There are two different views on the specific site and mechanism of $^1$O$_2$ production in the photosynthetic membrane. One of them favors the PSII reaction center, where the primary charge pairs recombination occurs as a prerequisite for the generation of $^1$O$_2$, and the other inclines to photosensitized $^1$O$_2$ formation by a substance located outside PSII. This article describes how we, as the advocators of the latter concept, have arrived at the conclusion that $^1$O$_2$ immediately involved in PSII photodamage is largely generated from the Rieske center of the cytochrome b$_{6}$/f complex and diffuses into PSII, attacking the reaction center subunits.s.

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Current Status and Future Prospects of White Root Rot Management in Pear Orchards: A Review

  • Sawant, Shailesh S.;Choi, Eu Ddeum;Song, Janghoon;Seo, Ho-Jin
    • 식물병연구
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    • 제27권3호
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    • pp.91-98
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    • 2021
  • The current social demand for organic, sustainable, and eco-friendly approaches for farming, while ensuring the health and productivity of crops is increasing rapidly. Biocontrol agents are applied to crops to ensure biological control of plant pathogens. Research on the biological control of white root rot disease caused by a soil-borne pathogen, Rosellinia necatrix, is limited in pears compared to that in apple and avocado. This pathogenic fungus has an extensive host range, and symptoms of this disease include rotting of roots, yellowing and falling of leaves, wilting, and finally tree death. The severity of the disease caused by R. necatrix, makes it the most harmful fungal pathogen infecting the economical fruit tree species, such as pears, and is one of the main limiting factors in pear farming, with devastating effects on plant health and yield. In addition to agronomic and cultural practices, growers use chemical treatments to control the disease. However, rising public concern about environmental pollution and harmful effects of chemicals in humans and animals has facilitated the search for novel and environmentally friendly disease control methods. This review will briefly summarize the current status of biocontrol agents, ecofriendly methods, and possible approaches to control disease in pear orchards.

담배 연기중(煙氣中)의 유해성분(有害成分) 감소(減少)에 관한 연구(硏究) (A study on reduction of harmful compound in cigarette smoke(I))

  • 김기환;배효원;박택규
    • Applied Biological Chemistry
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    • 제21권2호
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    • pp.131-136
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    • 1978
  • The effects of liquid sugar and sucrose on several characteristic of tobacco leaves, there combustibility and harmful compound in smoke were examined. results obtained were as follows. 1) Nicotine and total nitrogen content of tobacco leaves were reduced by sugars added to tobacco. 2) Nicotine and tar transfered to smoke were reduced by 4% sugars added to burley tobacco but not reduced by sugars added to hicks. 3) pH of smoke was reduced by sugars added but pH of tobacco shreds not reduced by sugars added. 4) The filling capacity and combustibility (S. B. R.) of tobacco shreds were increased by sugars treated. 5) Nitrogen oxides transfered to smoke was reduce by sugars treated but phenols transfered was not reduce by sugar treated. 6) The capacities of moisture absorption and retention was increased by sugars treated.

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대형디젤기관에서 DOC에 의한 배출가스 저감에 관한 연구 (A study on Emission Reduction by DOC on Heavy Duty Diesel Engine)

  • 한영출;류정호;오용석
    • 한국자동차공학회논문집
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    • 제7권5호
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    • pp.16-21
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    • 1999
  • The diesel vehicle is relatively superior to gasoline vehicle on the fuel consumption, durability and combustion efficiency. However, exhaust emission from diesel vehicle are known to be harmful to human health and environment. The treatment technologies for the diesel exhaust gases are classified as replacement of fuel, quality control of diesel fuel, improvement of engine and aftertreatment system. The most effective for the treatment technology is known to be aftertreatment system, and this research is continuously conducted by many groups. The DOC system has many advantages of reducing particulates and harmful gaseous substances such as CO. HC. Moreover, it is simple in device structure, relatively low cost, and easy to install witout retrofitting the vehicle. In this study, experiment were conducted to analyze the effects on factors of oxidation characteristics and conversion efficiency of DOC. In experiment, test was conducted to estimate engine emission in 11,000cc diesel engine which was equipped with DOC.

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Effects of Mecoprop Wettable Powder Concentrations on Growth and Yield of Flax

  • Kwon, Byung-Sun
    • Plant Resources
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    • 제7권1호
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    • pp.15-21
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    • 2004
  • This study was conducted to evaluate the effect of mecoprop-wp concentrations on weed control, growth characters and yield in flax, after 7cm and 14cm of plant height it to the field. The major weeds were Alopecurus aequalis var. a murensis (kom) ohwi, Persicaria hydropiper spach, Lamium amplexicaule L, Stellaria alsine Grimm var. undulata ohwi, Eleusine indica(L.) Gaertn. Flax yield were increased somewhat more with 250g/10a mecoprop-wp at 7cm of plant height than the other treatment and by hand weeding treatment of mecoprop-wp, 250g/10a at 7cm of plant height was slightly harmful for the flax with recommended concentration, On the other hand, all treatments were harmful in the double dosage level.

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