• Journal of Chest Surgery
• /
• 제5권2호
• /
• pp.87-96
• /
• 1972

Studies of blood gas and lung histopathology were done in 10 dogs after intrapericardlal aorto-right pulmonary arterial anastomosis with proximal ligation of the right pulmonary antery. Among the 5 expired during or after operation, in 3 cases, the causes of the death were due to surgical bleeding and, in 2 cases, acute cardiopulmonary insufficiency because of large anastomosis stoma measured respectively 7mm and 10mm. In the 5 of survivals, one was sacrificed because of empyema at postoperative 7 days and 2 were at postoperative one month and remained 2 at postoperative 3 month respectively. The following observations were made. 1.In every survival, continuous machinary murmur was auscultated and the angiograms of all long term survivals showed the good patency of the anastomosis stoma. 2.After the ligation of the right pulmonary artery, the values of $PO_2$ and $PCO_2$ in arterial and venous blood were generally decreased comparing with the preoperative values. The mean value of $P_aO_2$ noted $83.30{pm}11.875$[p<0.01]. After the shunts operation with ligation of the right pulmonary artery, the immediate values of PH, $PO_2$ and $PCO_2$showed no significant changes comparing with that of right pulmonary artery ligation only. In the cases of survivals more than one month, the values of $PO_2$ and $PCO_2$ in the arterial and venous blood were generally higher than that of ligation of the right pulmonary artery only. The $P_aO_2$ value noted $103.750{pm}7.395$[p<0.01]. The mean values of $P_aO_2$, $PCO_2$ and PH in the arterial and venous blood almost returned to that of preoperative studies. 3.In the specimens of lung from the cadavors expired due to acute cardiopulmonary insufficiency after the operation, there were massive congestion, hemorrhage in the alveolar spaces and bronchioles. In specimens obtained at postoperative one month, there were dilatation of alveolar spaces with partial rupture, slight congestion, and alveolar wall thickening in the lung parenchyme, but there was no significant changes in pulmonary vasculature except dilation of pulmonary capillaries. In the specimens obtained at postoperative three months, the alveolar walls were more thickened in the lung parenchyme than the finding of the specimens obtained at postoperative one month. In the wall of pulmonary capillaries, there was only slight thickening with connective tissue proliferatlon.

• Journal of Chest Surgery
• /
• 제40권2호
• /
• pp.97-102
• /
• 2007

배경 : 최근 하지 정맥류 치료에 정맥 내 레이저 치료가 도입되어 비침습적이면서도 좋은 치료 결과들이 많이 보고되고 있다. 저자들은 대복재정맥 역류로 인한 하지 정맥류 환자에서 980-nm 다이오드레이저를 이용하여 대복재정맥 폐쇄술을 시행하였으며 그 치료 효과를 분석하였다. 대상 및 방법: 2003년 9월부터 2006년 2월까지 대복재정맥 역류로 인한 하지 정맥류 환자 238명(332예)을 대상으로 980-nm 다이오드 레이저를 이용하여 정맥 내 레이저 치료를 시행하였다. 수술은 레이저 치료와 동시에 보행적 정맥류 제거술을 시행하였다. 수술 전 임상 양상과 수술 합병증, 그리고 수술 후 1개월과 3개월의 추적 듀플렉스 초음파 검사 결과를 분석하였다. 결과 : 수술 후 합병증으로는 대부분의 환자에서 반상 출혈이 발생하였고, 감각 이상이 68예(20.5%), 피부화상이 3예(0.9%) 발생하였다. 추적 초음파 검사에서 수술 1개월 후 26예, 3개월 후에는 10예에서 추가로 대복재 정맥 역류 혹은 부분 혈류재개가 확인되어 치료성공률은 각각 91.3%, 87.9%였다. 결론: 레이저를 이용한 대복재정맥 폐쇄술이 기존의 대복재정맥 발거술에 비하여 비침습적이기는 하지만 저자들은 다소 높은 대복재정맥의 재개통을 경험하였다. 이는 적절치 않은 레이저 강도나 적용 시간(속도), 과도하게 확장된 대복재정맥 등이 원인일 것으로 생각되며 시술 후 정맥의 재개통을 줄이기 위한 많은 연구 노력과 함께 초음파 검사를 통한 정확한 추적 관찰이 필요할 것으로 생각한다.

• 대한예방한의학회지
• /
• 제15권1호
• /
• pp.49-69
• /
• 2011

Objective : The object of this study was to observe the effects of Lonicerae Flos (LF) aqueous extracts on lipopolysaccharide (LPS)-induced rat acute lung injury. Method : Five different dosages of LF extracts were orally administered once a day for 28 days before LPS treatments, and then all rats were sacrificed after 5 hour-treatment of LPS. Eight groups of 16 rats each were used in the present study. The following parameters caused by LPS treatment were observed ; body weights, lung weights, pulmonary transcapillary albumin transit, arterial gas parameters (pH, $PaO_2$ and $PaCO_2$) bronchoalveolar lavage fluid (BALF) protein lactate dehydrogenase (LDH), and proinflammatory cytokines tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$) contents, total cell numbers, neutrophil and alveolar macrophage ratios, lung malondialdehyde (MDA), myeloperoxidase (MPO), proinflammatory cytokines TNF-${\alpha}$ and IL-$1{\beta}$ contents. In addition, the histopathologic changes were observed in the lung in terms of luminal surface of alveolus, thickness of alveolar septum, number of polymorphonuclear neutrophils. Result : As results of LPS-injection, dramatical increases in lung weights, pulmonary transcapillary albumin transit increases, increases in $PaCO_2$, decreases in pH of arterial blood and $PaO_2$, increases of BALF protein, LDH, TNF-${\alpha}$ and IL-$1{\beta}$ contents, total cells, neutrophil and alveolar macrophage ratios, TNF-${\alpha}$ and IL-$1{\beta}$ contents increases were detected with decreases in LSA and increases of alveolar septum and PMNs numbers, respectively as compared with intact control. These are means that acute lung injuries (resembling acute respiratory distress syndrome) are induced by treatment of LPS mediated by inflammatory responses, oxidative stress and related lipid peroxidation in the present study. However, these LPS-induced acute lung injuries were inhibited by 28 days continuous pretreatment of 250 and 500mg/kg of LF extracts. Because of lower three dosages of LF treated groups, 31.25 and 62.5 and 125mg/kg did not showed any favorable effects as compared with LPS control, the effective dosages of LF in LPS-induced acute lung injuries in the present study, is considered as about 125mg/kg. The effects of 250mg/kg of LF extracts showed almost similar effects with ${\alpha}$-lipoic acid 60mg/kg in preventing LPS-induced acute lung injuries. Conclusion : It seems that LF play a role in protecting the acute respiratory distress syndrome caused by LPS.

• 한국어병학회지
• /
• 제31권1호
• /
• pp.9-13
• /
• 2018

2017년 1월에서 4월까지 강원도 고성에서 사육중인 명태 친어로부터 수정란을 채집하여 신경괴사증바이러스(nervous necrosis virus, NNV)의 검출을 시도하였다. 매 회 50 mg씩 수정란을 채집하여 이를 1 set로 간주하였으며 총 37 set를 제작하였다. RNA를 추출하고 cDNA를 합성하여 NNV를 대상으로 reverse transcriptase PCR을 실시하였다. 그 결과, one-step PCR법으로는 37 set의 시료가 모두 음성이었으며, two-step PCR법으로는 5.4% (2/37)의 시료가 양성을 나타내었다. 그러나, band의 농도가 매우 낮아 시퀀싱은 불가능하였다. 본 연구의 결과 및 이전 연구의 결과로부터 현재 국내에서 양식하고 있는 명태에서 NNV 감염에 의한 폐사는 발생하지 않는 것으로 추정된다. 하지만, 지속적인 모니터링 및 양성 개체 출현 시 바이러스 분리의 시도 등은 필요할 것으로 생각된다.

• Restorative Dentistry and Endodontics
• /
• 제23권1호
• /
• pp.477-486
• /
• 1998

Recently the development of rotary instrument makes it possible that in root canal treatment operator saves much more time, maintans original curved canal shape and easily prepares continuous tapered root canal. The purpose of this experiment was to examine the smoothness of the internal surface of prepared root canal and the effectiveness of debridement in prepared root canal by SEM for the comparison of hand and Ni-Ti rotary instrument. 25 extracted human teeth were access opened and # 10 K-type file was introduced into canal until it was appeared at the apical foramen. The working length was established by subtracting 0.5mm from this measurement. Group 1. The root canal preparation was done to # 30 with working length and then step-back until # 45 with K-Flexofile (Maillefer, Swiss). Group 2. Root canal preparation was done by Naviflex Ni-Ti file (Brasseler, USA) as the same technique with group 1. Group 3. Canal was prepared by Profile .04 (Maillefer, Swiss) taper until #30. Group 4. With use of Quantec (Tycom, USA) root canal was prepared from file number 1 to 8. In group 1 and 2, the root canal irrigant was NaOCl and the other groups, NaOCl and RC-prep (Premine Dental Products, USA) was used. The prepared teeth were notched with high-speed bur as bucco-lingual direction and fractured with chisel and mallet, then examined with SEM. Group 1 showed smooth internal surface. There were scratches mainly to the axial direction. Group 2 showed similar characteristics to those in group 1. Group 3 showed more smoother and linear cutting surface with bised scratches. Group 4 has the almost same characteristics group 3 and there was no difference in the file design. Ni-Ti rotary root canal instrument prepare the dentinal wall more smoother than hand instrument. The effectiveness of debridement was not fully affected by file design. The isthmus area and accessory canals of the root canal system were not prepared in any group. According to the result, hand and rotary type instrumentation techniques were effective in removal of major amount of tissue from root canal but it was not complete. In the direction of cutting movement there was difference between them.

• 한국과학교육학회지
• /
• 제38권6호
• /
• pp.853-864
• /
• 2018

미래 과학자인 과학영재 학생들이 연구를 설계하고 수행하는 전과정에서 연구윤리를 어떻게 지키며 연구를 수행하여야 하는지에 대한 체계적이고 실질적인 교육이나 연구부정을 막기 위한 시스템적인 노력은 극히 최근에 시작되고 있지만 여전히 부족한 실정이다. 이 연구에서는 과학고와 영재고에 근무 중인 교사 68명을 대상으로 한국의 과학고와 영재고의 연구윤리교육과 윤리적 연구 환경 조성현황을 설문을 통해 알아보았다. 먼저 연구윤리교육현황을 살펴보면, 조사대상의 절반에 해당하는 학교가 연구윤리교육을 교육과정 내에 포함하고 있었다. 또, 반 이상의 교사가 수업 시간에 개인적으로 연구윤리를 가르친다고 응답하였고, 90%에 가까운 교사가 탐구 과정 중에 연구윤리를 가르친다고 응답하였다. 하지만 여전히 교사들은 연구윤리교육이 부족하다고 여기고 있었다. 다음으로, 연구윤리 준수를 위한 환경으로서, 연구윤리 규정과 시스템의 유무, 교사의 역량, 교사가 조성하는 동료검증, 자기검증 가능한 분위기, 연구윤리교육에 대한 관리자의 태도를 조사하였다. 지식과 경험 측면에서 교사는 역량을 갖추고 있었고, 동료, 자기 검증이 가능한 환경을 조성하고 있었다. 하지만 연구윤리규정과 검증 시스템은 학교에 충분히 갖추어져 있지 않다. 하지만 관리자들이 연구윤리교육에 대하여 높은 관심을 가지고 있으므로 충분히 개선될 것으로 보인다. 마지막으로, 교사들은 학생들의 윤리적 연구를 위해, 추가적인 연구윤리교육, 학생들의 태도 변화, 검증 시스템의 구축과 지속적 관리, 윤리적 환경조성, 명확한 지침 제공이 필요하다고 하였다. 이 결과는 각 영재학교에서 연구윤리교육 방향을 설정하는데 도움이 될 뿐 아니라, 영재 담당 교사들에게는 어떤 방식으로 학생들에게 도움을 줄지 계획하는데 도움이 될 것이다. 또한 과학영재 학생들을 둘러싸고 있는 외부적 환경을 학교와 교사가 어떻게 만들어나갈지에 대한 시사점을 얻을 수 있을 것이다.

• 한국방재안전학회논문집
• /
• 제14권4호
• /
• pp.61-67
• /
• 2021

본 연구에서는 도시 설계의 핵심 요소인 상수도 공급량의 적정성에 대해 살펴보았다. 상수도의 공급은 설계가 진행됨에 따라 다양한 방식으로 분석된다. 기초 자료 수집 분석을 시작으로 수급 계획을 수립하여 상수도 공급량을 산정하는데 본 연구에서는 인구추정과 원단위 산정의 적정성에 대하여 평가하였다. 실측자료를 확보할 수 있는 제 2기 신도시 중 위례신도시를 연구대상지역으로 선정하였다. 관련 자료를 분석하여 장래인구와 원단위를 확인하고 실측자료와 비교하였다. 위례신도시의 2020년 9월 기준 인구는 93,977명으로 계획인구 110,990명으로 약 84%의 적정성을 보임에 따라 계획인구와 실제 인구가 거의 유사하게 나타나는 것을 확인할 수 있었다. 원단위의 경우 설계 당시 서울지역 314ℓ/인, 성남지역의 320ℓ/인으로 산정되었다. 분석 결과, 계획도시 내의 공급량을 알아보면서 인구추정에 있어 어느 정도 일치함을 알 수 있었으나 현재 우리나라의 경우는 지속적인 개발에서 벗어나 기존의 도시 활성화에 대한 관심이 많은바, 구도심에 대한 공급량의 적정성에 관해서도 추후 연구가 필요가 있는 것으로 판단된다.

• 한국지반공학회논문집
• /
• 제24권10호
• /
• pp.57-70
• /
• 2008

피에조콘 관입시험의 장점은 연속적인 데이터의 취득이 보장되며 결국 대상지반의 신뢰성 있는 분석이 가능하다는 점이다. 따라서 지난 수십년간 국내외에서 콘 관입시험결과로부터 흙분류를 수행하는 많은 연구가 진행되었으며 차트나 도표 등의 형태로 흙분류 방법들이 제안되었다. 그러나 대부분의 차트 또는 방법들은 한국을 제외한 세계 각국의 자료들을 바탕으로 제안되어 국내 지반의 적용성에 대한 검증이 이루어져야 한다. 뿐만 아니라 기존 방법들에서는 사용된 입력자료에 따라 흙분류 결과가 상이한 경우가 있어 적용과 판단에 어려움이 있다. 그러나 불행히도 이러한 차트 형태로 제안된 기존 도표의 경우 지역성 등이 반영되어 수정 또는 보완이 필요하나 수정에 어려움이 있거나 거의 불가능하다. 이에 본 연구에서는 국내 17개 현장에서 수행된 피에조콘 관입시험결과와 채취된 시료에 대한 주상도 및 흙분류결과를 바탕으로 클러스터링 기법과 뉴로-퍼지 이론을 이용한 흙분류 모델을 제안하였다. 제안된 모델을 검증하기 위해 모델 학습 시 사용되지 않는 새로운 피에조콘 관입시험 데이터에 대한 흙분류 결과를 실제 시추결과와 비교하였다. 또한 기존의 소프트컴퓨팅 모델과 Robertson 방법에 의한 흙분류 결과와 제안된 모델의 흙분류 결과를 비교하여 제안된 모델의 효율성을 검토하였다.

• 대한소아치과학회지
• /
• 제25권2호
• /
• pp.352-367
• /
• 1998

Intracellular pH (pHi) plays an important role in the regulation of cellular processes by influencing the acitivity of various enzymes in cells. Therefore, almost every type of mammalian cell possesses an ability to regulate its pHi. One of the most prominent mechanisms in the regulation of pHi is $Na^+/H^+$ exchanger. This exchanger has been known to be activated when cells are stimulated by the binding of agonist to the muscarinic receptors. Therefore, the aims of this study were to compare the rates of $H^+$ extrusion through $Na^+/H^+$ exchanger before and during muscarinic stimulation and to investigate the possible existence of $HCO_3^-$ transporter which is responsible for the continuous supply of $HCO_3^-$ ion to saliva. Acinar cells were isolated from the rat mandibular salivary glands and loaded with pH-sensitive fluoroprobe, 2', 7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein(BCECF), for 30min at room temperature. Cells were attached onto the coverglass in the perfusion chamber and the changes in pHi were measured on the iverted microscope using spectrofluorometer. 1. By switching the perfusate from $HCO_3^-$-free to $HCO_3^-$-buffered solution, pHi decreased by $0.39{\pm}0.02$ pH units followed by a slow increase at an initial rate of $0.04{\pm}0.007$ pH units/min. The rate of pHi increase was reduced to $0.01{\pm}0.002$ pH units/min by the simultaneous addition of 1 mM amiloride and $100{\mu}M$ DIDS. 2. An addition and removal of $NH_4^+$ caused a decrease in pHi which was followed by an increase in pHi. The increase of pHi was almost completely blocked by 1mM amiloride in $HCO_3^-$-free perfusate which implied that the pHi increase was entired dependent on the activation of $Na^+/H^+$ exchanger in $HCO_3^-$-free condition. 3. An addition of $10{\mu}M$ carbachol increased the initial rate of pHi recovery from $0.16{\pm}0.01$ pH units/min to $0.28{\pm}0.03pH$ units/min. 4. The initial rate of pHi decrease induced by 1mM amiloride was also increased by the exposure of the acinar cells to $10{\mu}M$ carbachol ($0.06{\pm}0.008pH$ unit/min) compared with that obtained before carbachol stimulation ($0.03{\pm}0.004pH$ unit/min). 5. The intracellular buffering capacity ${\beta}1$ was $14.31{\pm}1.82$ at pHi 7.2-7.4 and ${\beta}1$ increased as pHi decreased. 6. The rate of $H^+$ extrusion through $Na^+/H^+$ exchanger was greatly enhanced by the stimulation of the cells with $10{\mu}M$ carbachol and there was an alkaline shift in the activity of the exchanger. 7. An intrusion mechanism of $HCO_3^-$ was identified in rat mandibular salivary acinar cells. Taken all together, I observed 3-fold increase in $Na^+/H^+$ exchanger by the stimulation of the acinar cells with $10{\mu}M$ carbachol at pH 7.25. In addition, I have found an additional mechanism for the regulation of pHi which transported $HCO_3^-$ into the cells.

• 비교문화연구
• /
• 제28권
• /
• pp.115-139
• /
• 2012

Interval or duration of segments, syllables, words and phrases is an important acoustic feature which influences the naturalness of speech. A number of cross-sectional studies regarding acoustic characteristics of children's speech development found that intervals of segments, syllables, words and phrases tend to change with the growing age. One hypothesis assumed that decreases in intervals would be greater when children were younger and smaller decreases in intervals when older (Thelen,1991), it has been supported by quite a number of researches on the basis of cross-sectional studies (Tingley & Allen,1975; Kent & Forner,1980; Chermak & Schneiderman, 1986), but the other hypothesis predicted that decreases in intervals would be smaller when children were younger and greater decreases in intervals when older (Smith, Kenney & Hussain, 1996). Researchers seem to come up with conflicting postulations and inconsistent results about the change trends concerning intervals of segments, syllables, words and phrases, leaving it as an issue unresolved. Most acoustic investigations of children's speech production have been conducted via cross-sectional designs, which involves studying several groups of children. So far, there are only a few longitudinal studies. This issue needs more longitudinal investigations; moreover, the acoustic measures of the intervals of child speech are hardly available. All former studies focus on word stages excluding the babbling stages especially the canonical babbling stage, but we need to find out when concrete changes of intervals begin to occur and what causes the changes. Therefore, we conducted an acoustic study of interval characteristics of segments and words concerning Canonical Babble ( CB) and early speech in an infant aged from 0;9 to 2;4 acquiring Mandarin Chinese. The current research addresses the following two questions: 1. Whether decreases in interval would be greater when children were younger and smaller when they were older or vice versa? 2. Whether the child speech concerning the acoustic features of interval drifts in the direction of the language they are exposed to? The female infant whose L1 was Southern Mandarin living in Changsha was audio- and video-taped at her home for about one hour almost on a weekly basis during her age range from 0;9 to 2;4 under natural observation by us investigators. The recordings were digitized. Parts of the digitized material were labeled. All the repetitions were excluded. The utterances were extracted from 44 sessions ranging from 30 minutes to one hour. The utterances were divided into segments as well as syllable-sized units. Age stages are 0;9-1;0,1;1-1;5, 1;6-2;0, 2;1-2;4. The subject was a monolingual normal child from parents with a good education. The infant was audio-and video-taped in her home almost every week. The data were digitized, segments and syllables from 44 sessions spanning the transition from babble to speech were transcribed in narrow IPA and coded for analysis. Babble was coded from age 0;9-1;0, and words were coded from 1;0 to 2;4, the data has been checked by two professionally trained persons who majored in phonetics. The present investigation is a longitudinal analysis of some temporal characteristics of the child speech during the age periods of 0;9-1;0, 1;1-1;5, 1;6-2;0, 2;1-2;4. The answer to Research Question 1 is that our results are in agreement with neither of the hypotheses. One hypothesis assumed that decreases in intervals would be greater when children were younger and smaller decreases in intervals when older (Thelen,1991); but the other hypothesis predicted that decreases in intervals would be smaller when children were younger and greater decreases in intervals when older (Smith, Kenney & Hussain, 1996). On the whole, there is a tendency of decrease in segmental and syllabic duration with the growing age, but the changes are not drastic and abrupt. For example, /a/ after /k/ in Table 1 has greater decrease during 1;1-1;5, while /a/ after /p/, /t/ and /w/ has greater decrease during 2;1-2;4. /ka/ has greater decrease during 1;1-1;5, while /ta/ and /na/ has greater decrease during 2;1-2;4.Across the age periods, interval change experiences lots of fluctuation all the time. The answer to Research Question 2 is yes. Babbling stage is a period in which the children's acoustic features of intervals of segments, syllables, words and phrases is shifted in the direction of the language to be learned, babbling and children's speech emergence is greatly influenced by ambient language. The phonetic changes in terms of duration would go on until as late as 10-12 years of age before reaching adult-like levels. Definitely, with the increase of exposure to ambient language, the variation would be less and less until they attain the adult-like competence. Via the analysis of the SPSS 15.0, the decrease of segmental and syllabic intervals across the four age periods proves to be of no significant difference (p>0.05). It means that the change of segmental and syllabic intervals is continuous. It reveals that the process of child speech development is gradual and cumulative.