• Title/Summary/Keyword: Low concentration

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Effect of Platycodon Grandiflorum Aqueous Extract on Lipid Levels in Rats

  • Kim Jeong-Seon
    • Nutritional Sciences
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    • v.9 no.3
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    • pp.167-172
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    • 2006
  • This study investigated the effects of Platycodon grandiflorum aqueous extract on lipid concentration of serum and liver in rats fed high cholesterol diet Male Sprague-Dawley rats were assigned to three groups (control, low dose of extract, high dose of extract) for four weeks. The serum total cholesterol concentration was significantly lower in the low and high doses of extract groups than in the control group. There was a significant decrease in the free cholesterol, cholesterol ester, LDL-cholesterol, and triglycerides concentrations in serum, and the total cholesterol and the triglycerides contentin liver in the low and high doses of extract groups compared to the control group. When the serum phospholipid concentration was compared among the groups, it was significantly lower in high dose of extract group than in control and low dose of extract group. It can be postulated that Platycodon grandiflorum aqueous extract may possess substantial hypolipidemic properties in rats.

Evaluation of Variation Method to Improve the Sensitivity of Immunoradiometric Assay (면역방사계수측정법의 민감도 향상을 위한 변법의 평가)

  • Won-Hyun Kwon;Mi-Ji Kang;;Ji-Sol Park;Jung-In Kim;Kyung-Jae Lee
    • The Korean Journal of Nuclear Medicine Technology
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    • v.27 no.1
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    • pp.29-35
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    • 2023
  • Purpose The concentration of PSA (Prostate Specific Antigen) after radical prostatectomy in prostate cancer patients is a predictor of biochemical recurrence, and the AUA (American Urological Association) is defined as biochemical recurrence when the concentration of PSA is measured at 0.2 ng/mL or more, and when the concentration is measured at 0.2 ng/mL or more at the retest. This standard is also applied our hospital. In this laboratory, the PSA reagent using IRMA (Immunoradiometric Assay) is used, and the sensitivity at a very low value was not as good as the reagent used in the department of laboratory medicine. This study aims to increase the reliability of the results by improving the precision and sensitivity of very low values. Materials and Methods As a reagent for the study, PSA reagent using IRMA was used. As a method to improve the precision and sensitivity of very low values, a variation method on the serum volume(25 uL, 50 uL, 100 uL, 200 uL) was studied, and variation usefulness evaluation was conducted. The evaluation items were compared the results of precision, analytical sensitivity, recovery rate, dilution test, high-dose hook effect test, parallel test and very low concentration values(n = 20). Results The validation results were displayed in the order of 25 uL, 50 uL, 100 uL, 200 uL. As the serum volume increased, it was confirmed that CV (Coefficient of Variation)(%) improved. Analytical sensitivity(ng/mL) was 0.038, 0.041, 0.017, 0.015 and recovery rate(%) was 101±3, 101±3, 99±2, 97±4. very low concentration values(ng/mL) between each volume(n=20) were 0.135±0.068, 0.076±0.050, 0.048±0.034, 0.046±0.034. and high dose hook effect appeared as the serum volume increased. Conclusion Through the variation usefulness evaluation, it was confirmed that as the serum volume increased, the precision and sensitivity improved at very low concentration values. However, it is necessary to pay special attention to the occurrence of high-dose hook effect as the serum volume increases. In the case of tests that requires very low concentration values, it is thought that the reliability of the result will be increased if the variation method is properly used after the variation usefulness evaluation.

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Health Impairment among Toluene exposed Workers (톨루엔 취급 근로자의 건강장해)

  • Moon, Young-Hahn;Roh, Jae-Hoon
    • Journal of Preventive Medicine and Public Health
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    • v.19 no.2 s.20
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    • pp.177-183
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    • 1986
  • Subjective symptoms, counts of blood cells and liver function test were conducted on 198 male workers who were exposed to toluene in Kyungin area from September to November, 1986. According to the level of urinary hippuric acid concentration, the total sample was classified into the high exposure group ($concentration{\geqq}3g/1$) and the low exposure group(concentration<3g/1). The following findings were obtained by comparing the two group: 1) Contrary to the previous findings. the urinary hippuric acid concentration of toluene exposed workers showed bimodal distribution. It meant that the toluene exposed workers were mixed with the non-exposed or minimal exposed workers. 2) The high exposure group showed a lower level of leucocytes counts ($6,630{\pm}1,860{\mu}l$) than the low exposure group ($6,340{\pm}1,960/{\mu}l$). 3) The high exposure group showed a higher level of SGOT, SGPT and r-GTP than the low exposure group (p<0.05). 4) The high exposure group complained much more subjective symptoms (e. g. skin rash, loss of appetite, palpitation) than the low exposure group.

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Improved Resolution of Paper-based Sensor for Proline Detection by Low-temperature Drying of Ninhydrin Solution (닌히드린 용액의 저온 건조에 의한 프롤린 검출을 위한 종이기반 센서의 분해능 개선)

  • Ji-Kwan, Kim;Young-Soo, Choi
    • Journal of Sensor Science and Technology
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    • v.31 no.6
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    • pp.428-432
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    • 2022
  • In this study, we describe the improvement of the resolution of a paper-based sensor by fabricating a high-concentration ninhydrin part using a low-temperature drying method to detect proline with high resolution. In the conventional paper-based sensor for detecting proline, the ninhydrin part is fabricated at room temperature, and in this process, the ninhydrin solution spreads around the ninhydrin part. Therefore, the concentration of the ninhydrin part becomes lower than that of the applied solution, lowering the resolution of the sensor. The proposed paper-based sensor better improved the sensitivity of the sensor compared to the existing sensor by fabricating a high-concentration ninhydrin part through drying the ninhydrin solution using a low-temperature drying method. Owing to the experiment, the intensity of the green color of the paper-based sensor with the integrated ninhydrin part fabricated at 10 ℃ is approximately 20% lower than the paper-based sensor with an integrated ninhydrin part fabricated at room temperature, indicating better sensor resolution. Therefore, the paper-based sensor with an integrated ninhydrin part fabricated at a high concentration could be useful for diagnosing drought.

A Study on the Simultaneous Reduction of NOx and Soot with Diesel-Methanol Stratified Injection System in a Diesel Engine (Part II : Combustion and Exhaust Characteristics of Stratified Injection) (층상연료분사(경유/메탄올)를 이용한 디젤엔진의 NOx와 Soot 동시 저감에 관한 연구 (제2보 : 층상분사 연소특성 및 배기 특성))

  • Kang, B.M.;Lee, T.W.;Chung, S.S.;Ha, J.Y.
    • Journal of ILASS-Korea
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    • v.7 no.1
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    • pp.7-13
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    • 2002
  • This paper is study on simultaneous reduction of NOx and soot for direct injection diesel engine using high and low cetane fuels. The stratified injection system was applied for diesel engine to use high and low cetane fuel. In this study, diesel fuel was used as high cetane fuels, methanol was used as low cetane fuels. Some parts of the injection system, ie. Nozzle holder. delivery vale, was remodeled to inject dual fuel sequentially from one injector. The leak injection quantity ratio of dual fuel was certificated by volumetric ratio at injection quantity experiment. According as concentration of low cetane fuel was varied, combustion experiment was performed using Toroidal and Complex chamber. Also, exhaust gas and fuel consumption were measured at the same time. Simultaneous reduction of NOx and soot was achieved at complex chamber regardless of concentration of low cetane fuel. However, according as concentration of low cetane fuel was increased, THC and CO was increased.

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Adaptive Response in CHO Cells by Bleomycin, Mitomycin C and Cadmium (Bleomycin, Mitomycin C 및 Cadmium에 의한 CHO 세포의 적응반응)

  • 김양지;한정호;정해원
    • Journal of Environmental Health Sciences
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    • v.18 no.2
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    • pp.117-124
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    • 1992
  • Pretreatment with low concentration of Bleomycin and Cadmium rendered Chinese Hamster Ovary Cells more resistant to the induction of chromosome aberration by subsequent high concentration of same agent, however Mitomycin C did not function in that way. The cells pre-exposed to low dose of Cadmitim did not show cross-resistance to challenge dose of Mitomycin C for the induction of chromosome aberration, but cells pre-exposed to Bleomycin showed cross resistance. And the cells pre-exposed to low dose of Mitomycin C showed cross resistance to challenge of Bleomycin, but Cadmium did not.

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A microscopic study on the rheological properties of human blood in low concentration limit

  • Kang, In-Seok
    • Korea-Australia Rheology Journal
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    • v.14 no.2
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    • pp.77-86
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    • 2002
  • A microscopic theoretical study is performed to predict the rheological properties of human blood in the low concentration limit. The shear thinning behavior of blood in the low shear limit is studied by considering the aggregate formation of red blood cells, which is called the rouleaux formation. Then the constitutive equations of blood in the high shear limit are derived for various flow situations by considering the unique features of deformation of blood cells. Specifically, the effects of the surface-area-preserving constraint and the lank-treading motion of blood cells on the rheological properties are studied.

Manufacture of Low Density Paper by Cationic Fatty Acid Amine Bulky Promotor Treatment (3) - Effect of Pulp Beating Degree and Bulky Promotor Concentration - (양이온성 지방산아민 벌키화제를 이용한 저밀도 종이 제조 (3) - 펄프 고해도 및 벌키화제 처리 농도에 따른 영향 -)

  • Nam, Yun-Seok;Choi, Kyoung-Hwa;Jin, Hai-Lan;Cho, Jun-Hyung
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.1
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    • pp.111-118
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    • 2016
  • The effects of pulp beating degree and bulky promotor concentration on the properties of handsheet including a bulk and strength have been investigated during manufacturing of low density paper (high bulk paper) with cationic fatty acid bulky promotor. It was found that paper bulk increased with increasing cationic fatty acid bulky agent concentration, while tensile strength decreased. On the other hand the opacity of handseets also increased with increasing cationic fatty acid bulky agent concentration, while brightness decreased slightly. With increasing pulp beating degree, paper bulk as well as tensile strength increased, while opacity decreased. Brightness did not show a significant difference with increasing pulp beating degree. The highest bulk and strength values were observed when 1.5% (SwBKP) and 2% (HwBKP) of bulky promotor was treated into the 450 mL CSF pulp slurry.

The Study of Correlation between Serum Vitamin K Concentration and Bone Metabolism in Postmenopausal Women (폐경후 여성에서 비타민 K와 골대사와의 상관성에 관한 연구)

  • 홍주영
    • Journal of Nutrition and Health
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    • v.32 no.3
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    • pp.287-295
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    • 1999
  • This study was conducted to observe the effect of vitamin K on bone metabolism in postmenopausal women. Twenty-four healthy postmenopausal women recruited for this one-month, double-blind controlled study. Before and after daily administration of 1.0mg of phylloquinone the levels of serum vitamin K, osteocalcin, under-carboxylated osteocalcin, and urinary deoxy-phyidinoline were measured. The serum vitamin K concentration of Koran women as well as the average dietary intake of vitamin K was shown to be higher than the average levels of foreign women. However, no correlation between serum vitamin K concentration and vitamin K intake was found. Also, serum vitamin K concentration showed no special correlation with either bone mineral density or bone turnover markers in the study group. However, women with low serum vitamin K concentration(vitamin K-low group)had lower bone mineral density levels. After supplementation with 1.0mg/day of vitamin K, there were no changes in the levels of serum vitamin K, osteocalcin, ucOC, or u-DPD. Vitamin K supplementation did not seem to have any positive effects on bone metabolism through carboxylation. It can, however, be expected that vitamin K supplementation has a positive effect on bone metabolism in postmenopausal women with especially low serum vitamin K concentrations.

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Characteristics of Air Pollution at Kimhae (김해지방의 대기오염 특성)

  • 박종길;김종필;김지형
    • Journal of Environmental Science International
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    • v.8 no.1
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    • pp.33-43
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    • 1999
  • This paper aims to describe the characteristics of air pollution using air pollutants concentration and meteorological data observed at Kimhae from December 1996 to November, 1997. The results are as follows : The concentration distribution of sulfur dioxide($SO_2$), carbon monoxide(CO), particulate matter(PM-10), and nitrogen dioxide($NO_2$) is high during the late fall and winter and low during the summer, but ozone concentration is low during the winter season and high during summer season except Jangma period and these distributions appear to be closely connected with insolation and the number of clear day. Diurnal variation of concentrations for sulfur dioxide, particulate matter, and carbon monoxide are high during the rush hours and nighttime and low during the daytime and these variations are distinct toward the winter season. And diurnal variation of nitrogen dioxide concentration has also same pattern and these patterns are closely related to the increasing traffic volume at rush hours. Diurnal variation of ozone concentration is generally increase for daytime and decrease for the late afternoon and are closely related to the insolation and photochemical reaction. The 24 hour average concentrations of air pollutant observed at Kimhae represented a positive correlation and a negative correlation for $O_3$ and also a negative correlation for the meteorological elements such as wind speed and cloud cover.

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