• 한국자기학회지
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• 제25권1호
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• pp.16-21
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• 2015

광 리소그래피 공정을 이용하여 GMR-SV(Giant magnetoresistance-Spin valve) 다층박막 위에 마이크로 크기의 바이오센서용 소자와 코일-채널을 적층으로 각각 제작하였다. 직경 $1{\mu}m$ 크기인 여러 개의 자성비드가 결합된 적혈구가 마이크로 채널로 지나갈 때 코일에 인가하는 AC 신호로 정지 또는 통과하는 적혈구 움직임을 조절하였다. GMR-SV 소자 위에 포획된 적혈구-자성비드가 갖는 미세자기장은 자기저항비를 변화시켜 검출용 출력신호 특성으로 나타났다. 이것을 이용하여 자성비드를 결합한 적혈구의 막 변형에 따른 운동 특성을 분석하는 바이오센서로 활용할 수 있음을 보여주었다.

• International Journal of Vascular Biomedical Engineering
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• 제4권2호
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• pp.7-12
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• 2006

The present study investigated the effects of the osmotic environment on the rheological properties of erythrocytes and their suspensions. In an iso-osmotic medium, erythrocytes forming a biconcave discocyte under resting conditions, exhibited high deformability. In a low-osmotic medium, the deformability of erythrocytes, which swelled and exhibited a spherical shape, significantly decreased at a high shear stress and the high-shear viscosity of the cell suspension was slightly higher than that of normal blood. Hyper-osmotic stress, however, which caused to form echinocytes, decreased cell deformability but exhibited smaller viscosity in low shear rates than iso-osmotic blood viscosity. These results showed a close relation with the aggregability measurements, in that hypertonic blood showed lower aggregability than the hypotonic and isotonic RBC suspensions. These findings indicate that the physicochemical environment has a strong influence on the rheological properties of the erythrocyte and its suspensions.

• 한국자기학회지
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• 제27권3호
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• pp.92-97
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• 2017

펄스자기장을 인체에 자극했을 때 몸 안에 있는 이온성 전해물질에 의해 유도전류가 발생하며, 최근에는 이를 활용하여 자기장 치료기술이 새롭게 연구 개발되고 있다. 본 연구에서는 강한 펄스자기장을 자극했을 때, 여러 층으로 응집되어 붙어있는 적혈구 연전형성의 변화를 동역학적으로 조사 분석하였다. 적혈구의 연전형성은 여러 가지 원인에 의해 발생하는데 물리학적으로 보면 적혈구 중심에 있는 $Fe^{+3}$ 이온에 의한 전기장 발생과 혈액 내에 녹아있는 음이온의 상호작용이 원인으로 고려된다. 본 연구에서 사용된 펄스자기장의 세기와 시간은 0.27 Tesla, 0.102 msec이고 펄스 반복시간은 1초이다. 인체에 가한 펄스자기장의 자극시간은 5분에서 10분, 15분, 20분까지 증가시켰고, 이에 따라 적혈구의 연전상태 변화를 동영상으로 조사하였다. 펄스자기장을 10분 동안 가했을 때 적혈구의 연전상태는 매우 호전되어 대체로 개별로 분리되었으며 slide glass 위에서 이동속도 역시 가장 활발하게 움직여서 $8{\times}10^{-4}m/sec$로 증가하였다. 그러나 20분까지 자기장 자극을 증가시키면 오히려 적혈구의 연전상태가 증가하고 활동성이 떨어지는 것을 확인하였다. 이에 대한 해석은 좀 더 체계적인 연구와 분석이 필요해 보인다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권4호
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• pp.208-213
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• 2023

Objectives: Orthognathic surgery is a corrective intervention for maxillofacial deformities. Bleeding is a major concern for oral and maxillofacial surgeons. Various agents, such as hemocoagulase, tranexamic acid, and aprotinin have been developed to reduce intraoperative bleeding and transfusion requirements. Therefore, in this study we aimed to investigate the effects of hemocoagulase and tranexamic acid, as well as their simultaneous use, to reduce bleeding during orthognathic surgery. Patients and Methods: This retrospective study included patients who had undergone simultaneous orthognathic surgery of the maxilla and mandible between January 2013 and September 2022 and were classified into three groups based on drugs administered: hemocoagulase (Botropase), tranexamic acid, and a combination of both drugs. We recorded patient age, sex, weight, blood loss, and duration of surgery. Red blood cell (RBC), hemoglobin, hematocrit, and platelet levels were measured before, immediately after, and one day after surgery. Results: No statistically significant differences were found in blood loss, RBC, hemoglobin, hematocrit, or platelet levels between any of the groups. There were no differences in the drug effects between Le Fort I and bilateral mandibular sagittal split osteotomies, with or without double genioplasty. However, there were significant reductions in RBC, hemoglobin, hematocrit, and platelet levels during genioplasty. Conclusion: Tranexamic acid, hemocoagulase, and their combination had similar efficacy in patients who underwent Le Fort I and bilateral mandibular sagittal split osteotomies with and without genioplasty.

• Childhood Kidney Diseases
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• 제3권1호
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• pp.104-108
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• 1999

Atypical hemolytic uremic syndrome associated with neuraminidase-producing Streptococcus pneumoniae usually associated with invasive infection such as fulminant pneumonia, sepsis, and meningitis and may occur earlier in lift and has a higher mortality rate than typical hemolytic uremic syndrome. We have experienced a 22-month-old female patient with hemolytic uremic syndrome associated with S. pneumoniae pneumonia and empyema. The patient was treated with ceftriaxone and washed red blood cell transfusion. As the disese course could be aggravated by the use of blood products containing anti-Tomsen-Friedenreich antigen, early recognition and sensible use of blood products such as washed RBC might lead to the improved outcome.

• Journal of Mechanical Science and Technology
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• 제17권7호
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• pp.1104-1110
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• 2003

The present study investigates the hemorheological characteristics of blood flow with applying vibration to a non-aggregating red blood cell suspension. In order to obtain the non-aggregating RBC suspension, blood samples were treated with vibration at a specified condition, which viscosities were taken before and after the treatment, respectively. The viscosity of the blood samples after treatment was higher than before treatment. These treated blood samples were forced to flow through a capillary tube that was vibrated perpendicularly to the direction of the flow. The experimental results showed that vibration caused a reduction of the flow resistance of the non-aggregated blood. The reduction of the flow resistance was strongly dependent on both frequency and amplitude of vibration. These results show potential in treating various diseases in the microcirculation associated with blood cell aggregation.

• 생물정신의학
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• 제5권2호
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• pp.235-242
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• 1998

Objectives : Alcohol-induced oxidative stress has been known to injure various tissues or organs. This stress is related with free radicals which are produced as the result of long-term alcohol consumption. Malonyldialdehyde(MDA) is produced by the interaction of free radicals and cell membrane lipids, and indicates the degree of lipid peroxidation indirectly. The purpose of this study was to investigate the relationship between red blood cell(RBC) membrane lipid peroxidation by free radicals, and associated hepatic injuries and hematologic changes. Methods : Thirty-three subjects diagnosed as alcohol dependence according to DSM-IV diagnostic criteria were evaluated within 72 hours after discontinuing alcohol drinking. Clinical characteristics were evaluated by CAGE questionnaire and Korean Michigan Alcoholism Screening Test(MAST). RBC membrane MDA level was measured as the marker of RBC membrane lipid peroxidation. Aspartate aminotransferase(AST), alanine aminotransferase(ALT) and gamma-glutamyltransferase(GGT) were used as the biochemical markers of liver damage due to alcohol ingestion. The alcohol-induced hematologic change was assessed by mean corpuscular volume(MCV). Results : The results were as follows. Clinical characteristics were not different between two groups having normal and abnormal levels of AST, ALT, GGT or MCV. The levels of MDA were not correlated with the clinical characteristics and serum levels of AST, ALT and GGT. However, there was a significant correlation between the levels of MDA and the value of MCV(p=0.017). Conclusions : These findings suggest that oxidative stress in alcohol dependence may not be reflected in liver enzyme markers such as AST, ALT and GGT, but may be reflected in MCV.

• 약학회지
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• 제42권1호
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• pp.75-81
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• 1998

Effects of swainsonine (SW: 8${\alpha}$, ${\beta}$-indolizidine-1alpha, 2${\alpha}$, 8${\beta}$-triol from Locoweed) on the cellular and nonspecific immune responses of lipopolysaccharide (LPS) wer e studied in ICR mice. Mice were divided into 4 groups (10mice/group), and LPS was given to each mouse 1 hr after i.p. injection with 3.7mg/kg of SW by i.p. injection twice a week for 14 days at a dose of 2mg/kg. Immune responses of the delayed-type hypersensitivity response (DTH) to sheep red blood cells (s-RBC), phagocytic activity and natural killer (NK) cell activity were evaluated. LPS treatment didn`t affect NK cell activity, phagocytic activity, DTH to s-RBC compared with those in controls, and phagocytic activity of sareoma 180 tumor bearing mice. However, circulating leukocytes were significantly decreased. Combinaton of LPS and SW increased circulating leukocytes significantly compared vath that in LPS alone, and DTH to s-RBC, NK cell activity and phagocytic activities of normal and sarcoma tumor bearing mice were not affected. These findings indicate that SW didn`t affected the cellular immune responses suppressed by LPS but significantly increased circulating leukocytes.

• Journal of Evidence-Based Herbal Medicine
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• 제2권1호
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• pp.43-49
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• 2009

Sodium arsenate and Yeonlyeonggobon-dan (nianlinggubendan) extract (YGD), a herbal restorative were treated p.o. 20 mg/kg and 500 mg/kg, respectively, and concurrently to rats, and examined the biochemical parameters in blood. The values of white blood cell (WBC), red blood cell (RBC), hemoglobin (Hgb) and hematocrit (Hct) in each group did not show significant variance. The value of aspartate aminotrasferase (AST) of arsenic-treated group was increased for 2 weeks significantly while that of the group of concurrent administration with YGD became low significantly compared with arsenic-treated group and the value of alkaline phosphatase (ALP) of arsenic-treated group was decreased while that of the group of concurrent administration with YGD was increased significantly compared with arsenic-treated group. In arsenic-treated groups, the value of glucose (Glu), and those of lactic dehydrogenase (LDH), blood urea nitrogen (BUN) and triglyceride (TG) were decreased at first but increased later while the groups of concurrent administration with YGD showed significant recovery from the toxicity of arsenic.

• Journal of Korean Biological Nursing Science
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• 제11권1호
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• pp.14-22
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• 2009

Purpose: This study was conducted to examine the clinical factors which affected the amount and the duration of infusion of intravenous (IV) heparin on ischemic stroke. Method: A cross-sectional descriptive study was designed to examine the factors. A total of 101 patients with ischemic stroke from a University hospital in G-city, Korea from January to December, 2006 were participated in this study. Data were analyzed by t- and ANOVA test, correlation coefficient, and stepwise multiple linear regression analysis. Result: This study showed that the patients who have been temporarily stopped to infuse iv heparin for more than one hour, had cardioembolic stroke, and had the lower count of initial red blood cell (RBC) had significantly lower amount of iv heparin infusion per body surface. In addition, this study founded that the patients with lower count of initial RBC and the lower level of initial blood sugar were significantly less likely to have the lower length of iv heparin infusion. Conclusion: Continuous monitoring and controlling the count of RBC and the level of blood sugar are needed to increase the efficacy of iv heparin therapy on ischemic stroke. Further empirical studies should be conducted to support the results of this study.