• Clinical and Experimental Pediatrics
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• 제46권10호
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• pp.1013-1018
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• 2003

목 적 : 천식 환자에서 특징적으로 존재하는 BHR의 기전으로 호산구성 기도 염증 반응이 중요시 생각되고 있다. 그러나 장기간 천식 관해 상태인 청소년에서 BHR이 지속되는 기전에 대해서는 아직 명확하지 않은 실정이다. 본 연구는 장기간 천식 관해 된 청소년에서의 BHR이 호산구성 기도 혈액내 총 호산구 증가와 혈청 ECP 농도의 증가와 연관되어 있는지 알아보고자 시행하였다. 방 법 : 서울대학교 어린이병원 소아과 외래에서 아토피성 천식으로 진단되었던 청소년 중 임상적으로 장기간 관해(최근 2년간 천식 증상이 없고 치료가 필요 없었던 경우)되었으나 BHR이 잔존하는 35명과 이들과 서로 대응하는 BHR을 갖고 있으면서 현증을 보이는 아토피 천식 청소년 35명을 대상으로 하였다. 이 두 군간의 총 호산구 수와 혈청 ECP 농도를 비교하고 각 군에서 총 호산구 수 및 혈청 ECP 농도와 $PC_{20}$ 사이에 상관 관계가 있는 지 분석하였다. 결 과 : 장기간 관해 된 군의 혈액 내 호산구 수와 혈청 ECP 농도의 평균값이 현증을 보이는 군보다 통계적으로 유의하게 낮았다($273{\pm}108$ vs. $365{\pm}178/{\mu}L$; $16.3{\pm}9.4$ vs. $26.5{\pm}15.1{\mu}g/L$, both, P<0.05). 현증을 보이는 군에서는 메타콜린 $PC_{20}$에 따라 혈액 내 호산구 수 및 혈청 ECP 농도가 각각 통계적으로 유의한 음의 상관관계를 보였으나(r=-0.385, P=0.022; r=-0.439, P=0.008) 장기간 관해 된 군에서는 유의한 상관관계를 보이지 않았다(r=-0.292, P=0.089; r=-0.243, P=0.159). 결 론 : 이와 같은 소견은 장기간 관해시의 BHR은 호산구성 염증과 연관성이 없으며 현증 천식에서의 BHR과는 다른 기전으로 설명될 수 있을 것으로 추정된다. 장기간 천식 관해 된 청소년에서 BHR이 잔존하는 기전에 대하여 정확히 밝히기 위해서 향후 BAL, 조직 검사, 유도 객담 등을 이용한 연구를 시행할 필요가 있다.

• Korean Chemical Engineering Research
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• 제47권6호
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• pp.747-754
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• 2009

본 연구에서는 $1,000^{\circ}C$에서 24시간 열처리된 활성탄에서 다이옥신과 유사구조를 갖는 o-DCB(ortho-dichlorobenzene)의 등온흡착식을 실험을 통하여 구하였고, 분자모사를 통하여 예측하였다. 실험으로 분석된 활성탄의 분자식 및 작용기 비율을 바탕으로 초기 활성탄 기본구조를 설계한 후, COMPASS(condensed-phase optimized molecular potentials for atomistic simulation studies) force field를 이용하여 이 구조를 최적화하였다. 최적화된 활성탄 분자구조에서 공극률, 비표면적, 및 입자밀도의 모사결과는 실험값과 비교되었고, 이들에 대한 실험과 모사결과의 오차는 각각 7.62, 3.79, 2.80%를 보여주었다. 통계 열역학적 방법인 GCMC(Grand Canonical Monte Carlo) 기법을 이용하여, 최적화된 활성탄 구조에서 온도에 따른 o-DCB의 등온흡착 상수값을 예측하였으며, 이 모사결과는 실험값과 비교될 때, 3% 이하의 오차를 보였다. o-DCB의 흡착특성을 바탕으로 확인되어진 활성탄 구조에서 다이옥신의 일종인 2,3,7,8-TCDD(tetrachlorodibenzo-p-dioxin) 등온흡착상수, 흡착열, 그리고 기공확산계수를 최종적으로 구함으로서, 실험적으로 구하기 힘든 맹독성 잔류성 유기물질의 흡착특성을 분자모사기법을 통하여 예측하였다.

• Journal of Korean Neurosurgical Society
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• 제46권4호
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• pp.389-396
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• 2009

Objective : Triptolide (TP) has been reported to suppress the expression of mitogen-activated protein kinase (MAPK) phosphatase-1 (MKP-1), of which main function is to inactivate the extracellular signal-regulated kinase-1/2 (ERK-1/2), the p38 MAPK and the c-Jun N-terminal kinase-1/2 (JNK-1/2), and to exert antiproliferative and pro-apoptotic activities. However, the mechanisms underlying antiproliferative and pro-apoptotic activities of TP are not fully understood. The purpose of this study was to examine whether the down-regulation of MKP-1 expression by TP would account for antiproliferative activity of TP in immortalized HT22 hippocampal cells. Methods : MKP-1 expression and MAPK phosphorylation were analyzed by Western blot. Cell proliferation was assessed by $^3H$-thymidine incorporation. Small interfering RNA (siRNA) against MKP-1, vanadate (a phosphatase inhibitor), U0126 (a specific inhibitor for ERK-1/2), SB203580 (a specific inhibitor for p38 MAPK), and SP600125 (a specific inhibitor for JNK-1/2) were employed to evaluate a possible mechanism of antiproliferative action of TP. Results : At its non-cytotoxic dose, TP suppressed MKP-1 expression, reduced cell growth, and induced persistent ERK-1/2 activation. Similar growth inhibition and ERK-1/2 activation were observed when MKP-1 expression was blocked by MKP-1 siRNA and its activity was inhibited by vanadate. The antiproliferative effects of TP, MKP-1 siRNA, and vanadate were significantly abolished by U0126, but not by SB203580 or SP600125. Conclusion : Our findings suggest that TP inhibits the growth of immortalized HT22 hippocampal cells via persistent ERK-1/2 activation by suppressing MKP-1 expression. Additionally, this study provides evidence supporting that MKP-1 may play an important role in regulation of neuronal cell growth.

• Tuberculosis and Respiratory Diseases
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• 제77권4호
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• pp.172-177
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• 2014

Background: Pseudomonas aeruginosa infection is particularly associated with progressive and ultimately chronic recurrent respiratory infections in chronic obstructive pulmonary disease, bronchiectasis, chronic destroyed lung disease, and cystic fibrosis. Its treatment is also very complex because of drug resistance and recurrence. Methods: Forty eight cultures from 18 patients with recurrent P. aeruginosa pneumonia from 1998 to 2002 were included in this study. Two or more pairs of sputum cultures were performed during 2 or more different periods of recurrences. The comparison of strains was made according to the phenotypic patterns of antibiotic resistance and chromosomal fingerprinting by pulsed field gel electrophoresis (PFGE) using the genomic DNA of P. aeruginosa from the sputum culture. Results: Phenotypic patterns of antibiotic resistance of P. aeruginosa were not correlated with their prior antibiotic exposition. Fifteen of 18 patients (83.3%) had recurrent P. aeruginosa pneumonia caused by the strains with same PFGE pattern. Conclusion: These data suggest that the most of the recurrent P. aeruginosa infections in chronic lung disease occurred due to the relapse of prior infections. Further investigations should be performed for assessing the molecular mechanisms of the persistent colonization and for determining how to eradicate clonal persistence of P. aeruginosa.

• 한국통신학회논문지
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• 제25권1A호
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• pp.81-89
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• 2000

본 논문에서는 CATV/LAN 전송망에서 우선권 문제에 주안을 두어서 해석한다. CATV/LAN 전송망에서 주요 해석의 대상인 상향 채널은 단방향 채널 특성과 단말의 위치에 따라서 우선적으로 접속되는 특성을 발생한다. 그리고, 트래픽(traffic)에 대한 우선권문제(priority)가 대두된다. 이런 공정성 문제와 우선권 문제를 해결하기 위하여 전송할 데이터가 발생하며 Pi확률로 데이터를 전송하는 CSMA-CD/U/P-P(Unslotted prioritized Pi-persistent CSMA-CD)프로토콜을 제안한다. 우선권 문제는 2-Class(high, low)로 가정하였다. 성능해석과 시뮬레이션 결과 우선권 문제가 주어진 환경하에서의 2개의 시나리오(scenario)를 가정하여 데이터전송 확률값인 Pi를 구하였으며, 전송망의 공정성이 이루어 졌을 때 평균 지연 시간을 비교하였다. 또한, 지연시간의 분산값을 구하였으며 버퍼큐(buffer queue)에서의 큐길이(queue length) 분포도 구하였다. 특히 헤드엔드 시스템에 가까운 단말이 포함될수록 평균 지연 시간이 길어지는 특징을 나타내고 있다.

• 약학회지
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• 제45권4호
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• pp.366-377
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• 2001

Persistent organochlorine pesticides has been used intensively in agriculture for a long time. The occurrence of organochlorine pesticides in the environment and subsequently in parts of the food chains, results in the intake of these compounds by human and animal. The measurement of the levels of organochlorine pesticides in tissues or blood of human populations is a good marker in evaluating the extent of exposure and hazards. So, most countries have conducted initial monitoring programs to determine organochlorine pesticides and polychlorinated biphenyls in human tissues. But, in Korea, a few research has been reported. In this study, the legally prohibited organochlorines, such as, $\alpha$-BHC, $\beta$-BHC, ${\gamma}$-BHC, $\delta$-BHC, p,p'-DDT, p,p'-DDD, p,p'-DDE, endrin, dieldrin and aldrin were determined in human blood, brain, adipose tissue, kidney cortex and liver tissues collected at autopsy of 10 men and 10 women, 16~65 years of age. Almost all the organochlorine pesticides mentioned previously were determined in human tissue samples indicated that they have been widely distributed in Korean human body. No significant difference was found in the levels of organochlorine pesticides between sexes, districts and ages.

• Journal of Microbiology
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• 제33권3호
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• pp.178-183
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• 1995

The recombinant plasmid of pCU103 constructed by cloning pcbCD genes in pBluescript SK(+) was studied for the effect of temperature on its persistence in different waters by the methods of electrophoresis, Southern hybridization, quantification, and transformation. The plasmid was very rapidly degraded out in non-sterile FW water without regards to water temperature, probably due to the effect of biochemical factor such as nucleases. The pCU103 was most persistent at 4$^{\circ}C$ in any water environments, moderately persistant at 15$^{\circ}C$ but least stable at 3$0^{\circ}C$ such results could be explained by the facts that hydrogen bonds in double-stranded plasmid DNAs become unstable and that nucleases are activated by increasing temperature. The intact structure of pCU1-3 was generally observed by gel electrophoresis under the conditions which the plasmid should be 2.0 ng/$\mu\textrm{l}$ or higher in concentration and that about 10$^2$ CFU/ml or more transformant cells should be recovered.

• Journal of Chest Surgery
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• 제25권12호
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• pp.1502-1507
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• 1992

Between February and July 1992, videothoracoscopic bullectomy was performed in nineteen patients with primary spontaneous pneumothorax. The indications of this surgery are recurrent in 12, persistent airleakage in 4 and previous contralateral pneumothorax in 3 patients. For the good operative field, we used double lumen endotracheal tube and put the CO2 gas into the thoracic cavity to make the lung collapse. We usually apply the endoGIA or electric cauterization for handling the bleb or bullae and there were 9 cases with of endoGIA only, 4 electric cauterization only and 6 both procedures. To evaluate the advantage of the Videothoracoscopic surgery, we compared surgical results with that of the tho-racotomy group[19 patients]. There were significant differences in operative time[93.8$\pm$41.9 min and 17.1$\pm$53.9 min, p< 0.01] and postoperative airleakage duration[35.6$\pm$113.3 hours and 117.9$\pm$214.4 hours, p<0.05] between the Videothoracoscopy and thoracotomy group. Tube indwelling time was shortened in Videothoracoscopy group[p<0.05]. The hospital stay was very short[p<0.01] and the patients needed analgesic injection less frequentley in videthoracoscopic group[p<0.05] In conclusion, we prefer the Videothoracoscopic procedure to the thoracotomy in uncomplicateed patients with pneumothorax because of simple procedure and good results.

• 한국간호교육학회지
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• 제25권2호
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• pp.173-185
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• 2019

Purpose: This study was conducted to develop and test effects of flipped learning on a health education program for allergic rhinitis patients. Methods: The study was a nonequivalent control group pretest-posttest design, with 38 participants (experimental group: 19, control group: 19). The education program for allergic rhinitis patients with flipped learning developed for this study was conducted in pre-class, in-class, and post-class stages for a total of 12 weeks. For the in-class stage, a TREAT model suitable for patient education program was developed. Data were analyzed with an independent t-test and repeated measures ANOVA. Results: The experimental group showed significant improvement in knowledge (F=15.029, p<.001), self-efficacy (F=6.814, p<.001) and self-care behavior (F=41.761, p<.001). In addition, subjective symptoms (F=61.453, p<.001) and quality of life (F=52.413, p<.001) improved. Conclusion: The results of this study show that flipped learning in an education program is an effective method for those in their twenties persistent moderate-severe allergic rhinitis. Therefore, the education program for allergic rhinitis developed by this study is actively recommended for nurses or health managers at universities to educate subjects in their twenties with allergic rhinitis.

• Journal of Korean Neurosurgical Society
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• 제67권2호
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• pp.202-208
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• 2024

Objective : Failed back surgery syndrome (FBSS) is a common long-term complication following spine surgeries characterized by chronic persistent pain; different strategies of management were employed to deal with it. This clinical trial aims to compare the efficacy of Pregabalin and Gabapentin in the management of this condition. Methods : A double-blind, randomized, comparative study (clinical trial registry NCT05324761 on 11th April 2022) with two parallel arms with Pregabalin and Gabapentin were used in arms one and two, respectively. Visual analog scale was used for basal and endpoint assessment of pain. T-test and analysis of covariance were used to deal with different variables. A pairwise test was used to compare pairs of means. Results : Of 66 patients referred to the trial, 64 were eligible, with 60 patients completing the 30 days trial. Both pregabalin and gabapentin effectively reduce pain, with significant p-values of 0.001 for each group. However, the pregabalin group was superior to gabapentin in pain reduction (p=0.001). Gender was an insignificant factor (p=0.574 and p=0.445 for the pregabalin and gabapentin groups, respectively, with a non-significant reduction (p=0.393) for both groups in total. Location of stenosis before surgery and type of surgery performed show non-significant effect on pain reduction for both groups. Conclusion : Both pregabalin and gabapentin effectively and safely relieve neuropathic pain associated with FBSS; pregabalin was significantly more effective irrespective of the patients' gender.