• Journal of Radiation Protection and Research
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• v.16 no.1
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• pp.1-13
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• 1991

Effective dose equivalents resulting from inhalation of indoor radon-222 daughters at 12 residential areas in Korea were assessed by a simple mathematical lung dosimetry model based on the measurements of long-term averaged radon concentrations at 340 dwellings. The long-term averaged indoor radon-222 concentrations and corresponding eqilibrium equivalent radon $concentration(EEC_{Rn})$ measured by passive time-integrating CR-39 radon cups are in the range of $33.82{\sim}61.42Bq/m^3(median\;:\;48.90Bq/m^3)$ and of $13.53{\sim}24.57Bq/m^3(median\;:\;19.55Bq/m^3)$, respectively. The effective dose equvalent conversion factor for the exposure to unit $EEC_{Rn}$ derived in this study was estimated $1.07{\times}10^{-5}mSv/Bq\;h\;m^{-3}$ for a reference adult and agreed well with those recommended by the ICRP and UNSCEAR. The annual average dose equivalent to the lung $(H_{LUNG})$ from inhalation exposure to measured $EEC_{Rn}$ was estimated to be 20.90 mSv and resulting effective dose $equivalent(H_E)$ was to be 1.25 mSv, which is about 50% of the natural radiation exposure of 2.40 mSv/y to the public reported by the UNSCEAR.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.1
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• pp.26-33
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• 2001

The goal of this study was to evaluate the relationship between ambient hexavalent chromium concentration and the concentration of the chromium in whole blood, plasma, erythrocytes, and its urinary excretion of male rats after inhalation exposure of sodium chromate during 1, 2, and 3 weeks. 1. Differences of mean chromium concentration in urine, whole blood, erythrocytes, and plasma of male rats exposed to sodium chromate by exposure level were statistically significance, respectively. 2. At low and high exposure groups, differences of mean chromium concentration in urine, whole blood, erythrocytes, and plasma of male rats by duration of inhalation exposure were statistically significance, respectively. 3. Ratio of whole blood chromium to plasma chromium increased with the increased duration of inhalation exposure of sodium chromate. 4. Ambient hexavalent chromium was positively and strongly correlated with in erythrocyte chromium, and also erythrocyte chromium was strongly correlated with in whole blood chromium. In conclusion, this study showed that chromium in erythrocyte increased with the increased exposure level and exposure duration, therefore this study suggests that chromium in erythrocytes is a good biological exposure index of the internal dose from exposure to soluble hexavalent chromium compound.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2009.11a
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• pp.425-426
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• 2009

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.1-8
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• 2005

The purpose of this study was to investigate the potential subacute toxicity of dimethyl disulfide by 3 weeks inhalation in F344 rats. The test article, dimethyl disulfide was exposed by inhalation to male and female rats at dose levels of 0, 5, 25, or 125 ppm/6 hrs/ day for 3 weeks. Five rats/ sex/ group were sacrificed on day 4 after the initiation of treatment, while 5 rats/ sex/ group were sacrificed at the end of treatment period. During the test period, clinical signs, mortality, body weights, food consumption, hematology, serum biochemistry, and gross findings were examined. Slight decreases in body weight gain were noted in both sexes of the highest dose group in a dose dependent manner but were only statistically different from the control animals in males of the group. A slight non-significant reduction in food consumption were also noted in the both sexes of the highest dose group. There were no adverse effects on mortality, clinical signs, hematology, serum biochemistry, and necropsy findings at any dose tested. Based on these results, it was concluded that the 3 weeks repeated dose of dimethyl disulfide by inhalation resulted in suppressed body weight gain and decreased food consumption at 125 ppm of both sexes. In the present experimental conditions, the target organ was not determined in rats. The no­observed-adverse-effect level (NOAEL) was considered to be 25 ppm/6 hrs/day for both sexes.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.6
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• pp.1784-1794
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• 2004

To study the effects between Cd inhalation toxicity and methanol extract of Radix Achyranthis Bidentatae, 4 rat groups were exposed to Cd aerosol by whole-body inhalation exposure for 6 hours/day, 5 days/week, and 4 weeks. Cd concentration in air was 0.98㎎/㎥ and mass median diameter(MMD) was 1.78㎛. 3 different dose intraperitoneal injections of methanol extract of Radix Achyranthis Bidentatae to 3 inhalation exposure groups applied for 4 weeks and the results were as follows: The highest body weight gain for 4 weeks and food intake per day were from inhalation exposure group Ⅲ(p<0.05). The highest lung weight was from inhalation exposure group Ⅲ and the highest liver and kidney weight were from inhalation exposure group Ⅱ(p<0.05). The lowest Cd content in lung was 22.77㎍/g from inhalation exposure group Ⅲ(p<0.05). The highest Cd concentration in blood was 11.71㎍/㎗ from inhalation exposure group Ⅰ(p<0.05). Cd concentrations of 14.87㎍/g in liver and 17.91㎍/g in kidney were the highest from inhalation exposure group Ⅰ(p<0.05). The lowest Cd concentration in liver and kidney were 5.71㎍/g and 3.17㎍/g from the control(p<0.05). For weekly Cd concentration in urine, the highest value was 0.48㎍/㎖ from inhalation exposure group Ⅲ of the 3rd week and inhalation exposure group Ⅰ, Ⅱ of the 4th week. For weekly Cd concentration in feces, the highest value was 0.32㎍/g from inhalation exposure group Ⅰ, Ⅱ, Ⅲ. The highest metallothionein concentration in lung was 89.02㎍/g from inhalation exposure group Ⅲ(p<0.05). The highest metallothionein concentrations in liver and kidney were 265.47㎍/g and 214.21㎍/g from inhalation exposure group Ⅲ, respectively(p<0.05). The highest Hct, Hb, and WBC values were from inhalation exposure group Ⅱ and the highest RBC value was from inhalation exposure group Ⅲ(p<0.05). Mostly damaged part in liver tissue was hepatic lobule and the degrees of damage were lessened by the intraperitoneal injection of methanol extract of Radix Achyranthis Bidentatae. Proximal, distal convoluted tubules and glomerulus in kidney tissue were mostly damaged part. Degeneration and swelling were partially observed but the degrees of kidney tissue damage were lessened more or less by the intraperitoneal injection of methanol extract of Radix Achyranthis Bidentatae.

• Korean Journal of Adult Nursing
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• v.21 no.4
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• pp.379-390
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• 2009

Purpose: The study was done to investigate the effect of ethanol inhalation on postoperative nausea in patients using Patient Controlled Analgesia (PCA). Methods: The data were collected from June 1st 2006 to September 30th, 2007. The subjects were 70 patients who had had orthopedic surgery under general anesthesia. The levels of the Visual Analogue Scale (VAS) was used to measure postoperative nausea. The experimental group was given ethanol inhalation using ethanol pads and the control group received normal saline pads. All participants were instructed to take two deep sniffs with the pad one inch from the nose. This was repeated every five minutes for three doses. The collected data were analyzed using SPSS/WIN 12.0 program. Results: The study supported all hypotheses. "The experimental group given first dose of ethanol inhalation would have a lower level postoperative nausea compared to the control group"(t = -5.900, p = .000). "The experimental group given second doses of ethanol inhalation would have a lower level postoperative nausea compared to the control group"(t = -7.507, p = .000). "The experimental group given third doses of ethanol inhalation would have a lower level postoperative nausea compared to the control group"(t = -6.685, p = .000). Conclusion: According to these results, the ethanol inhalation can be considered an effective nursing intervention for relieving the postoperative nausea in patients using PCA.

• Journal of Radiation Protection and Research
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• v.47 no.4
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• pp.237-245
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• 2022

Background: The current study reports measurements of activity concentrations of radon (²²⁰Rn) and thoron (²²⁰Rn) in dwellings, followed by inhalation dose assessment of the public, and then by the development of regulation and the national radon action plan (NRAP) in Cameroon. Materials and Methods: Radon, thoron, and thoron progeny measurements were carried out from 2014 to 2017 using radon-thoron discriminative detectors (commercially RADUET) in 450 dwellings and thoron progeny monitors in 350 dwellings. From 2019 to 2020, radon track detectors (commercially RADTRAK) were deployed in 1,400 dwellings. It was found that activity concentrations of radon range in 1,850 houses from 10 to 2,620 Bq/㎥ with a geometric mean of 76 Bq/㎥. Results and Discussion: Activity concentrations of thoron range from 20 to 700 Bq/㎥ with a geometric mean of 107 Bq/㎥. Thoron equilibrium factor ranges from 0.01 to 0.6, with an arithmetic mean of 0.09 that is higher than the default value of 0.02 given by UNSCEAR. On average, 49%, 9%, and 2% of all surveyed houses have radon concentrations above 100, 200, and 300 Bq/㎥, respectively. The average contribution of thoron to the inhalation dose due to radon and thoron exposure is about 40%. Thus, thoron cannot be neglected in dose assessment to avoid biased results in radio-epidemiological studies. Only radon was considered in the drafted regulation and in the NRAP adopted in October 2020. Reference levels of 300 Bq/㎥ and 1,000 Bq/㎥ were recommended for dwellings and workplaces. Conclusion: Priority actions for the coming years include the following: radon risk mapping, promotion of a protection policy against radon in buildings, integration of the radon prevention and mitigation into the training of construction specialists, mitigation of dwellings and workplaces with high radon levels, increased public awareness of the health risks associated with radon, and development of programs on the scientific and technical aspects.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.10 no.1
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• pp.96-107
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• 2003

Objective: The purpose of this study was to identify the effects of tracheal suction and the effects of different methods of bronchodilator inhalation (Ultrasonic nebulizer: MDI puff, MDI puff with spacer) in VSD surgery patients. Material & Method: From June 2001 to March 2002, sixty consecutive patients were randomly assigned to a control group (n= 15), ultrasonic nebulizer group (n=15), metered dose inhalation (MDI) puff group (n=15) and MDI with spacer group (n=15). Vital signs (HR, BP, CVP), ABGA and pulmonary functions were measured before suction (baseline for suction), after suction, 15 minutes after suction (base of bronchodilator inhalation), 30 minutes after bronchodilator inhalation, and 2 hours after bronchodilator inhalation. Stastistical analysis was performed using SPSS software. Repeated measure ANOVA was used to examine the effects of tracheal suction. One way ANOVA with Bonferroni's correction and multiple range test (the least significant difference test) were used to examine the effects of albuterol inhalation. Result: 1. Heart .ate increased significantly immediately after suction (p<.01) and recovered 15 minutes after suction. 2. $PaO_2$ and PH decreased significantly immediately after suction (p<.05) and $PaO_2$ recovered 15 minutes after suction. $PaCO_2$ increased immediately after suction and significantly 15 minutes after suction (p<.01). But changes in vital signs and ABGA were within the normal range. 3. Tidal volume decreased significantly 15 minutes after suction (p<.05). 4. Changes of HR and tidal volume were greater in the nebuizer group compared to the other groups (p<.05) 30 minutes after bronchodilator inhalation and recovered 2 hours after bronchodilator inhalation. 5. Changes of airway deadspace was greater in the nebulizer group compared to the control group and MDI puff group 30 minutes after albuterol inhalation (p<.05) and at 2 hours (p<.01). Conclusion: Tracheal suction did not have significant effect on vital signs and pulmonary functions after OHS. Although the methods of bronchodilator inhalation did not showed any significant difference on pulmonary function, the nebulizer method increased $PaO_2$ (20%) and tidal volume transiently. If the patient needs bronchodilator inhalation with bronchospasm after OHS, the nebulizer method is the best choice. More study on the effects of bronchodilator inhalation in bronchospasm group is needed.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.126-126
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• 2003

Welding fume (WF) induces pulmonary disease including pneumoconiosis. To investigate whether reactive oxygen species-induced oxidative DNA damage occurs during welding fume exposure and the upregulation of DNA repair mechanisms is accompanied, SPF SD rats were exposed to welding fumes with the concentrations of 65.6${\pm}$2.9 mg/㎥(low dose) and 116.8${\pm}$3.9 mg/㎥ (high dose) of total suspended particulate for 2 hrs per day in an inhalation chamber for a total of 2hrs, 15 or 30 days.(omitted)

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.343.2-343.2
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• 2003