• 감성과학
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• 제22권1호
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• pp.55-64
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• 2019

스트레스는 자율신경계 반응의 변화를 수반하며, 특히 심박변이도 지표는 스트레스에 의한 자율신경계의 활동을 반영하는 양적 지표로 사용된다. 본 연구에서는 스트레스 완화를 위한 산소와 색채 조명의 복합 자극이 제시되는 동안 자율신경계 반응의 변화를 확인하였다. 42명의 실험참가자는 지난 2주 동안 경험한 스트레스에 대한 증상들을 스트레스 반응 척도에 평가하였다. 스트레스 평가 후, 실험참가자는 복합 자극을 제시받았고, 자극 제시 전과 후, 그리고 자극이 제시되는 동안 심전도 신호가 기록되었다. 자극 조건은 30% 농도의 산소와 백색 조명, 산소와 주황색 조명과 산소와 파란색 조명의 조합의 세 가지로 구성되었다. 심박률(HR), R-R간격의 표준편차(SDNN), 연속한 R-R 간격 차이 값의 평균제곱근(RMSSD)과 심박변이도의 저주파 성분(LF), 고주파 성분(HF), 그리고 LF와 HF의 비율을 심박변이도 지표로 추출하였다. 이들 지표는 자극 제시 전과 후의 평균을 비교하는데 활용되었다. 결과는 자극 조건이 제시되고 난 후, HR과 LF/HF ratio의 유의한 감소를 보여주었다. 특히, 산소와 파란색 조명이 제시된 조건에서 다른 두 조건보다 유의하게 큰 RMSSD와 HF의 증가 및 LF/HF ratio의 감소가 나타났다. 이는 30% 농도의 산소와 파란색 조명의 조건이 부교감신경의 활성화에 의한 자율신경의 균형을 유발하여 스트레스 이완에 가장 효과적임을 보여주었다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권9호
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• pp.1336-1344
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• 2014

The effects of various packaging systems, vacuum packaging (VACP), medium oxygen-modified atmosphere packaging (50% $O_2/20%$ $CO_2/30%$ $N_2$, MOMAP), MOMAP combined with vacuum skin packaging (VSP-MOMAP), high oxygen-MAP (80% $O_2/20%$ $CO_2/30%$ $N_2$, HOMAP), and HOMAP combined with VSP (VSP-HOMAP), on the activity of antioxidant enzyme, and oxidation and color stabilities in sliced Hanwoo (Korean cattle) beef loin were investigated at $4^{\circ}C$ for 14 d. Higher (p<0.05) superoxide dismutase activity and total reducing ability were maintained in VSP-MOMAP beef than in HOMAP beef. Lipid oxidation (2-thiobarbituric acid reactive substances, TBARS) was significantly (p<0.05) retarded in MOMAP, VSP-MOMAP, and VSP-HOMAP beef compared with HOMAP beef. Production of nonheme iron content was lower (p<0.05) in VSP-MOMAP beef than in HOMAP beef. Red color ($a^*$) was kept higher (p<0.05) in VSP-MOMAP beef compared with MOMAP, HOMAP, and VSP-HOMAP beef. However, VACP beef was found to have the most positive effects on the antioxidant activity, oxidation and red color stabilities among the various packaged beef. These findings suggested that VSP-MOMAP was second to VACP in improving oxidation and color stabilities in sliced beef loin during chill storage.

• Journal of Dental Anesthesia and Pain Medicine
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• 제18권1호
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• pp.47-56
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• 2018

Background: The purpose of this study is to investigate the effects of administration order when a sedative drug (midazolam) and an opioid analgesic drug (fentanyl) is applied for moderate intravenous (IV) sedation in dentistry. Methods: A retrospective chart review was conducted in one dental clinic during its transition from a midazolam-first to a fentanyl-first protocol for dental procedures requiring moderate IV sedation. Physiological parameters, drug administration times, patient recovery times, drug dosages, and patient recall and satisfaction were investigated for differences. Results: A total of 76 charts (40 midazolam-first and 36 fentanyl-first administrations), were used in the analysis. Administering midazolam first resulted in an average 4.38 min (52%) decrease in administration times (P < 0.001), and a decrease in procedural recollection immediately following the procedure (P = 0.03), and 24 to 48 hours later (P = 0.009). Administering fentanyl first required an average of 2.43 mg (29%) less midazolam (P < 0.001). No significant differences were found for change in vital signs, minimum oxygen saturation levels, recovery times, and patient satisfaction (P > 0.05). Oxygen saturation levels did not drop below 90% for either group; however, 5 cases in the fentanyl-first group fell to between 90% and 92%, compared with 0 cases in the midazolam-first group. Conclusions: The administration order of fentanyl and midazolam may have different effects on patients and the sedation procedure. Findings from this study should be used to facilitate discussion among dental practitioners and to guide additional research investigating this topic.

• 대한인간공학회지
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• 제29권6호
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• pp.853-860
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• 2010

This study investigated differences in blood oxygen saturation($SpO_2$) and heart rate(HR) according to flow rate, gender, and phase in males and females in their 60s when the supply of 93% highly concentrated oxygen administration was changed (1L/min, 3L/min, and 5L/min). It recruited totally 20 elderly subjects including 10 males($68.0{\pm}2.6$ years) and 10 females ($65.5{\pm}3.1$ years). The experiment consisted of three phages of Rest 1(5 min), Hyperoxia(10 min), and Rest 2(10 min), and $SpO_2$[%] and HR[bpm] were measured during all phages. $SpO_2$ was higher in Hyperoxia phase supplied with highly concentrated oxygen than in Rest phases. Higher flow rate was associated with more increase in $SpO_2$. HR was reduced in Hyperoxia phase compared to Rest phases. More supply of highly concentrated oxygen was associated with more decrease of HR. However, there were no differences in both $SpO_2$ and HR according to gender.

• 약학회지
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• 제32권4호
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• pp.287-293
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• 1988

Oxygen free radical have recently been found to mediate cell injury after ischemia in the kidney. The purpose of our study was to determine whether selenium had an effect on damge mediated by oxygen free radical in inorganic mercury induced renal failure, toxic model of renal failure. Toxic renal failure model was produced by subcutaneous injection of mercuric chloride (4mg/kg) once a day for 7 consecutive days. In additionally, coadministration of sodium selenite (1mg/kg) was performed by the same condition. As a consequence of this study, we were able to detect partially unequivocal role of selenium as below dipicted. The combination of sodium selenite showed that markedly inhibited production of superoxide radical in mercuric chloride alone. On the other hand, combined sodium selenite was unable to enhance against significantly lowered superoxide dismutase activity after mercuric chloride insult. However, simultaneous administration of sodium selenite was inclined to induce mitochondrial superoxide dismutase and catalase.

• Neonatal Medicine
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• 제18권1호
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• pp.130-136
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• 2011

목적: Chloral hydrate는 검사 시 진정 목적으로 흔히 사용하는 약물이나 신생아에 관해서는 충분한 연구가 이루어지지 않고 있다. 이에 저자들은 신생아중환자실에서 chloral hydrate의 사용 시에 나타나는 부작용의 빈도와 그에 영향을 미치는 요소에 대해 알아보고자 한다. 또한 chloral hydrate만으로 진정이 되지 않아 추가 약물을 투여하는 경우 부작용이 증가하는지에 관해 알아보고자 한다. 방법: 2010년 3월부터 2011년 2월까지 가톨릭대학교 서울성모병원 신생아중환자실에서 검사 시 진정 목적으로 chloral hydrate를 사용한 104명을 대상으로 의무기록을 후향적으로 조사하였다. 결과: Chloral hydrate 투여 시 부작용은 41.3%에서 나타났으며 산소 포화도 감소(18.8%), 무호흡 증가(17.5%), 서맥 증가(10%), 수유량 감소(3.8%)가 있었다. Chloral hydrate 투여 시부작용은 chloral hydrate 투여 시기에 산소 투여 여부와 관련이 있었다(odds ratio [OR], 10.911: 95% confidence interval [CI], 2.082-57.178). 추가 약물 투여는 chloral hydrate 투여 시 산소 투여 여부와 관련이 있었고(OR, 4.151: 95% CI, 1.455-11.840) chloral hydrate 단독 투여 군에 비해 수유량 감소를 제외하고는 부작용에 유의한 차이가 없었다. 결론: 진정 요법이 필요한 검사 시 산소를 투여하고 있는 신생아에서 chloral hydrate의 사용은 부작용이 나타날 가능성이 높고 추가 약물 투여의 가능성이 높다. 추가 약물 투여가 필요한 경우에는 진정 유도 후 나타나는 수유량 감소에 주의하면서 진정을 유도할 수 있겠다.

• 대한치과마취과학회지
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• 제2권1호
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• pp.1-6
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• 2002

The usage of nitrous oxide is increased for the anxious patient to dental treatment. There are two methods to induce the sedation during dental treatment. One is sedation with drugs the other no need of drugs. We discussed here about sedation with drugs. The methods of drug administration are oral, intramuscular, intravenous, inhalation. The method of oral administration of drugs are convenient to patient and doctor but poor controllability. Intramuscular method is a parenteral technique that maintains several advantages over the enteral technique. However its pales in comparison to other parenteral technique. Intravenous method represents most effective method of ensuring predictable and adequate sedation in all patients. But it has inability to reverse the action of drugs after they have been injected except some drugs (e.g., narcotics and benzodiazepine). A variety of gaseous agents may be administered by inhalation to produce sedation. In dental practice, the inhalation administration of gas means use of nitrous oxide. There are many advantages of nitrous oxide administration. First, very short latent period and rapid onset of drug action which lead to possible titration of drug concentration. With nitrous oxide, clinical effects may become noticeable as quickly as 15 to 30 seconds after inhalation. Recovery from inhalation sedation is also quite rapid. In out patient dental practice rapid recovery is very important because it permit to discharge the patient without escort and the patient return to their ordinary life without limit. To success the conscious sedation with nitrous oxide, the administrator should be keep the mind that always titration of nitrous oxide concentration during induction and treatment. Careful observation need during treatment to prevent oversedation because the adequate nitrous oxide concentration to patients changed by environmental stress. Always begins with 100% oxygen and ends with 100% oxygen to prevent diffusion hypoxia which rare in clinical practice.

• 대한수의학회지
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• 제37권3호
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• pp.619-627
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• 1997

It is known that 2-methyl-1,4-naphtoquinone(menadione, MD) induces hepatotoxicities both in vivo and in vitro. These toxic effects are believed to result from oxidative damages to hepatocytes by "active oxygen" species via one-electron reduction of the naphtoquinone. The ginsenoside(GS) is a complex mixture of individual ginsenosides which is known to produce a range of effects on the cardiovascular and central nervous systems. In particular, GS has an antioxidant effect. In this experiment we studied the effect of GS from red panax ginseng(red ginseng total saponin, RGTS) on free radical-induced liver injuries by MD. Administration of MD($150{\mu}M$) caused an increase in aspartate aminotransferase(AST) activities and lipid peroxidation, decrease in alkaline phosphatase(ALP) activities and total bilirubin levels in blood, caused depletion of GSH and changes of antioxidant enzyme(superoxide dismutase, catalase) activities are shown in liver tissue. Administration of RGTS restored the AST levels that increased by MD, but catalase showed no significant changes. RGTS also had an effect of restoring the GSH level and had some synergistic effects with SOD. These data suggest that RGTS may have some protective effects on liver injury which is related with the oxygen free radical.

• Tuberculosis and Respiratory Diseases
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• 제84권3호
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• pp.217-225
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• 2021

Background: Despite the proven benefits of dexamethasone in hospitalized coronavirus disease 2019 (COVID-19) patients, the optimum time for the administration of dexamethasone is unknown. We investigated the progression of COVID-19 pneumonia based on the timing of dexamethasone administration. Methods: A single-center, retrospective cohort study based on medical record reviews was conducted between June 10 and September 21, 2020. We compared the risk of severe COVID-19, defined as the use of a high-flow nasal cannula or a mechanical ventilator, between groups that received dexamethasone either within 24 hours of hypoxemia (early dexamethasone group) or 24 hours after hypoxemia (late dexamethasone group). Hypoxemia was defined as room-air SpO₂ <90%. Results: Among 59 patients treated with dexamethasone for COVID-19 pneumonia, 30 were in the early dexamethasone group and 29 were in the late dexamethasone group. There was no significant difference in baseline characteristics, the time interval from symptom onset to diagnosis or hospitalization, or the use of antiviral or antibacterial agents between the two groups. The early dexamethasone group showed a significantly lower rate of severe COVID-19 compared to the control group (75.9% vs. 40.0%, p=0.012). Further, the early dexamethasone group showed a significantly shorter total duration of oxygen supplementation (10.45 days vs. 21.61 days, p=0.003) and length of stay in the hospital (19.76 days vs. 27.21 days, p=0.013). However, extracorporeal membrane oxygenation and in-hospital mortality rates were not significantly different between the two groups. Conclusion: Early administration of dexamethasone may prevent the progression of COVID-19 to a severe disease, without increased mortality.

• 한국화재소방학회논문지
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• 제32권5호
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• pp.1-5
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• 2018

창문이 설치된 대부분의 공간에서는 커튼을 사용한다. 이러한 커튼은 대부분 가연성 소재이며 수직 설치되어 있기 때문에 화염확대의 중요 요인이다. 따라서 커튼과 같은 가연성 실내장식물의 연소특성에 관한 연구는 화재성상을 예측하는데 있어 매우 중요하다. 본 연구에서는 실내장식재로 널리 사용되는 6종류 커튼의 연소특성을 분석하기 위해 상온과 고온에서의 산소지수를 측정하였다. 실험결과 모든 시료의 고온산소지수는 상온에서보다 약 3~7.5% 낮게 측정되었으며 약 0.2%의 산소농도 차이로도 시료별 연소현상이 큰 차이를 나타냈다. 따라서 가연성 내장재의 산소지수 값으로 난연성을 평가할 경우 고온산소지수 값에 대한 충분한 고려가 있어야 할 것으로 판단된다.