• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.98.1-98
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• 1999

No Abstract, See Full Text

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.481-481
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• 2005

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2001.10b
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• pp.183-183
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• 2001

• Biomolecules & Therapeutics
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• v.18 no.3
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• pp.286-293
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• 2010

Cytokine production is a sensitive indicator for monitoring perturbations of the immune system by xenobiotics in animals and humans. In the present study, we evaluated the changes in $IFN{\gamma}$, IL-5 and $TNF{\alpha}$ mRNA expression after atrazine (ATZ), perfluorooctanoic acid (PFOA) or zearalenone (ZEA) exposure in Jurkat cells. The IC50 (concentration for a 50% inhibition of cell proliferation) of PFOA and ZEA after 3 days culture were $226.6\;{\mu}M$ and $52.6\;{\mu}M$, respectively. The effects of ATZ on cytokine expression followed in increasing order of $IFN{\gamma}$>IL-5>$TNF{\alpha}$ at $3\;{\mu}M$ and at the lower concentrations the degree of effects on three cytokines were less clear between the cytokines when compared to control level. PFOA had marked increasing effect in order of $IFN{\gamma}$>$TNF{\alpha}$>IL-5 mRNA expression at IC50, and these patterns were continued at the lower concentrations, IC50/2 and IC50/4. ZEA caused the overexpression of cytokine mRNAs in order of IL-5>$IFN{\gamma}$>$TNF{\alpha}$ at both IC50 and IC50/2, and at IC50/4 the overexpression order was IL-5>$TNF{\alpha}$. On other hand, $IFN{\gamma}$ was less distinct compared to the control. These data indicate that ATZ, PFOA and ZEA caused the overtranscription of $IFN{\gamma}$, IL-5 and $TNF{\alpha}$ mRNA, and the overproduction of these cytokines may eventually lead to immune disorders.

• Korean Journal of Weed Science
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• v.10 no.2
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• pp.99-102
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• 1990

Pearl millet (Pennisetum americanum (L.) Leeke) has been found as a promising new forage crop of higher quality and yield in Korea since 1985. The objective of the study was to select preemergence herbicides for weed control in growing pearl millet in order to reduce production cost and with increased yields. Propazine (Milogard 4L) was the best in controlling weeds without its phytotoxicity at the standard application rate, and with the highest survival rate of seedlings of peal millet "Suwon 1" hybrid. Sprayings with Atrazine and Simazine caused lower survival rate of peal millet and with their light phytotoxicity as compared with manual weeding and Propazine spraying. Alachlor killed pearl millet seedlings almost completely. Pendimethalin also was not good for weed control of peal millet due to its severe phytotoxicity and with very low survival rate of pearl millet seedlings.

• Bulletin of the Korean Chemical Society
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• v.10 no.2
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• pp.196-200
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• 1989

Some s-triazine herbicides, namely simazine, atrazine, and propazine present as trace components in a complex mixture were analyzed by GC/MS and GC/MS/MS methods. Even though monitoring the molecular ions was the best in terms of sensitivity, adequate analysis could not be done when interfering species were present. When doubly charged ions which appeared at characteristic m/z values were monitored, chromatograms were rather free from interference. More importantly, selected reaction monitoring was found to provide a selective means of detection with general applicability.

• Analytical Science and Technology
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• v.15 no.6
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• pp.489-495
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• 2002

In this study, we determined distribution status of organonitrogen pesticides such as trifluralin, atrazine, metribuzin, alachlor, malathion, nitrofen, permethrin, cypermethrin, fenvalerate, and parathion accumulated in the fresh water fishes and amphibians. We collected those samples at 31 sites from the basin of major rivers, and separated the muscular tissue as a final sample for analysis. In the pretreatment process, lipid was eliminated by using acetonitrile and n-hexane, and pesticides were reextracted with dichloromethane. The extract was dehydrated and concentrated, and then cleaned it up by passing the Florisil column, and pesticide content was finally determined by using a GC-MS system after introducing isotope labelled references. The accumulation level was observed in the range of $0.17{\sim}6.8{\mu}g/kg$ in amphibians and $0.26{\sim}16{\mu}g/kg$ in fishes including cypermethrin as $16{\mu}g/kg$.

• Mass Spectrometry Letters
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• v.9 no.3
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• pp.77-80
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• 2018

The focus of this paper is to present techniques to overcome certain difficulties in quantitative analysis with a time-of-flight mass spectrometer (TOF-MS). The method is based on conventional solid-phase extraction, followed by reversed-phase ultra high performance liquid chromatography of the extract, and mass spectrometric analysis. The target compounds included atenolol, atrazine, caffeine, carbamazepine, diclofenac, estrone, ibuprofen, naproxen, simazine, sucralose, sulfamethoxazole, and triclosan. The matrix effects caused by high concentrations of organic compounds in wastewater are especially significant in electrospray ionization mass spectroscopy. Internal-standard calibration with isotopically labeled standards corrects the results for many matrix effects, but some peculiarities were observed. The problems encountered in quantitation of carbamazepine and triclosan, due to nonlinear calibration were solved by changing the internal standard and using a narrower mass window. With simazine, the use of a quadratic calibration curve was the best solution.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.175-175
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• 2001

This experiment tested whether in utero and lactational exposure to 4-nonylphenol (NP) alters mammary gland differentiation in the female offspring rat. Pregnant Sprague Dawley rats were administered NP (l0, 100 mg/kg), atrazine (l00 mg/kg), pesticide demonstrating antiestrogenic activity in mammary gland development, or vehicle (0.5% methyl cellulose) by oral gavage from gestation day 15-19.(omitted)

• The Korean Journal of Ecology
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• v.15 no.3
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• pp.257-265
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• 1992

The effects of insecticide dimilin including the technical grade(tg) and wettable power(wp-25), inhibiting the synthesis of chitin in the cuticle of insect larvae, and herbicides alachlor and atrazine on the development of shrimp caridina denticulata denticulata were investigated in various concentrations. This species is abundant in the freshwater such as river and pond. The shrimp larvae were reared at dimilin solutions(tg and wp 2), alachlor solutions, and atrazin solutions. the concentrations of dimiline were 0, 1, 5, 10 and 25 ppb dimilin solutions, and those of alachlor and atrazin were 0, 1, 5, 10 and 25ppm, respectively.mortality was high at 10 ppb when the larvae were exposed to dimilin and at 25ppm in the case of alachlor and atranzine solutions. If lethal concentration is defined as a concentration in which less than 10% of larvae to the post larval stage from hatching it can be concluded that the lethal concentration of dimilin is 5ppb, and that of alachlor and atrazin is 25 ppm.