• Journal of the Korean Wood Science and Technology
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• 제24권1호
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• pp.54-67
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• 1996

Micromorphology of the vessel wall sculptures such as perforation plate, inter-vessel pits, vessel-ray pits, vessel-parenchyma pits, vestured pits, spiral thickening, and warts was observed in 78 species(45 genera, 25 families) of Korean hardwoods using a scanning electron microscopy. The SEM observation revealed the micromorphology of vessel wall sculptures which have not yet been described, and have confirmed findings already established at the light microscopical level.

• Journal of the Korean Wood Science and Technology
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• 제9권1호
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• pp.1-12
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• 1981

The structure of spiral thickenings, particulary the appearance, arrangement and orientation of thickenings in compression wood of Torreya nucifera, were studied in detail by light and polarizing microscope, scanning and transmission electron microscope. The results obtained are as follows: (1) Using the inclined sections at an angle of 45 degrees to the fiber axis, it seems that we can not only observe the more accurate transverse view of the thickenings but also investigate the formation of their thickenings. (2) Generally 2-4 pieces of thickenings are projected to the cell lumen as nipple-like appearance in transverse section and are as frequent, well developed, forming pair and have the rope-like appearance in radial surface. (3) The secondary wall of early wood is composed of 3 layers (S1, S2, S3) and orientation of thickening appears S helix but that of late wood is of 2 layers (S1, S2) and that orientation shows Z helix. Above two regions are demaracted at several tracheid cells from the growth ring boundary. (4) Orientation of thickening seems to be a element showing the characteristics of compression wood in Torreya nucifera. (5) It believes that the thickenings of compression wood are integral part of the S3 in early wood tracheids and of the S2 in late wood and have the same orientations as the inner-most microfibrils in these layers. (6) Thickening and cavities seem to be not formed together in a secondary cell wall of same tracheids.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제24권3호
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• pp.279-287
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• 2021

Purpose: The clinical implications of bowel wall thickening (BWT) on abdominal computed tomography (CT) among children are unknown. We aimed to suggest a new method for measuring BWT and determining its clinical significance in children. Methods: We retrospectively analyzed 423 patients with acute abdomen who underwent abdominal CT; 262 were classified into the BWT group. For this group, the pediatric radiologist described the maximal bowel wall thickness (MT), normal bowel wall thickness (mm) (NT), and their ratios for each segment of the bowel wall. Results: In the thickened bowel walls, the thickness differed significantly between the small bowel (6.83±2.14 mm; mean±standard deviation) and the colon (8.56±3.46 mm; p<0.001). The ratios of MT to NT in the small bowel (6.09±3.17) and the colon (7.58±3.70) were also significantly different (p<0.001). In the BWT group, 35 of 53 patients had positive fecal polymerase chain reaction results; 6 patients infected with viruses predominantly had BWT in the small intestine, while the terminal ileum and the colon were predominantly affected in 29 patients with bacterial infections. In the initially undiagnosed 158 patients with BWT, the symptoms improved spontaneously without progression to chronic gastrointestinal disease. Conclusion: This study provides a clinical reference value for BWT in the small intestine and colon using a new method in children. The BWT on abdominal CT in children might indicate nonspecific findings that can be observed and followed up without additional evaluation, unlike in adults.

• Tuberculosis and Respiratory Diseases
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• 제59권6호
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• pp.591-599
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• 2005

Asthma is the most common disease of the lungs, and one that poses specific challenges for the physicians including radiologist. This article reviews for the clinical diagnosis, Radiologic features, and differential diagnosis of asthma, and outlines the radiologic features of the complications of asthma. Bronchial wall thickening and hyperinflation characterize the chest radiograph of the patients with asthma. On CT scan one may see airway wall thickening, thickened centrilobular structures, and focal or diffuse hyperlucency. Apparent bronchial dilatation may be seen, but the diagnosis of bronchiectasis should be made with caution. Quantification of changes in the airway wall and lung parenchyma may be valuable in understanding the mechanisms of asthma and in evaluating the effects of treatment. The challenge for the physician evaluating the images of a patient with asthma is to find complications.

• 대한핵의학회지
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• 제37권5호
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• pp.278-287
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• 2003

목적: 생존심근 진단에 있어 니트로글리세린 투여 Tc-99m-MIBI 게이트 심근SPECT의 진단성능을 휴식/지연재분포 Tl-201 심근SPECT와 비교하였다. 대상 및 방법: 22명의 관상동맥질환자에서 Tl-201 휴식/디피리다몰 부하 Tc-99m-MIBI 게이트 지연재분포 Tl-201 심근SPECT를 시행하였다. 이 때 게이트SPECT 시행 후 니트로글리세린 0.6 mg을 설하투여하고 연이어 그 자리에서 게이트SPECT를 1회 더 반복 시행하였다. 환자들에게 관상동맥우회로술을 시행하고 3개월 후 게이트 심근SPECT를 추적검사로 시행하였다. 20 분절 모델을 이용하여 각 분절에서 휴식, 지연재분포, 기저상태와 니트로글리세린투여 후의 심벽운동 및 수축기비후화 등을 정량하였다. 정량화된 생존심근 예측지표들 중, (1) 휴식기 Tl-201 섭취, (2) Tl-201 지연재분포, (3) 기저상태의 수축기비후화, (4) 니트로글리세린 투여 후의 수축 기비후화, 네 가지의 예측성능을 평가하고 비교하였다. 결과: 총 100개의 분절이 분석에 포함되었으며, 이 중 66개(66%)의 분절이 재관류 후 기능 회복을 보였다. 최적 기준점인 50%를 기준으로 하였을 때, ROC 곡선 분석에서 휴식기 Tl-201 섭취와 Tl-201 지연재분포의 민감도, 특이도는 각각 79%와 44%, 그리고 82%와 44%였다. 또한 15%를 기준으로 하여, 기저상태 수축기비후화와 니트로글리세린 투여 후 수축기비후화의 민감도, 특이도는, 각각 49%, 50%와 64%, 65%였다. ROC 곡선의 AUC는 니트로 글리세린 투여 후 수축기비후화가 기저시 수축기비후화에 비하여 유의하게 높았다(p=0.004). 결론: 니트로글리세린 투여 Tc-99m-MIBI 정량적 게이트 심근SPECT는 기능이상 심근에서 기능 회복을 예측하는데 유용한 검사이다.

• 치과방사선
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• 제27권1호
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• pp.283-295
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• 1997

The purpose of this study was to evaluate the Waters' views, panoramic and periapical radiograms as well as clinical symptoms in the diagnosis of maxillary sinusitis. The author analyzed the types of mucosal thickenings, the types of bony wall changes, the pathologic changes of antral floors and total amount of agreement on radiograms in 495 patients with 505 maxillary sinuses which demonstrated radiographic changes. The results were obtained as follows : 1. 125 cases (24.8％) showed the mucosal thickening of antral floor and lateral wall (Type II), 106 cases (20.9％) showed the mucosal thickening around the whole antral wall (Type N) and 75 cases (14.8％) showed increased radiopacity of whole antrum. 2. Among 505 cases of mucosal thickenings, 319 cases<63.2％) showed the bony wall changes: 114 cases (35.9％) showed the thinning of lateral walls, 105 cases (32.8％) showed the thickening of lateral walls and 47 cases(14.7％) showed indistinct antral walls. 3. Among 6 types of mucosal thickenings, the incidence of bony wall changes was high in type VI(73.3％) and in type IV(71.6％). 4. 139 cases(25.1％) showed no pathologic change of antral floor, 127 cases(22.9％) showed the indistinct antral floor and 122 cases (22.1％) showed the halo appearance of antral floor on panoramic and periapical radiograms. 5. 449 cases (88.9％) showed apparent increased radiopacity and 47 cases(9.3％) showed suspicious increased radiopacity on Waters' views. 280 cases (71.6％) showed apparent increased radiopacity and 88 cases (22.5％) showed suspicious increased radiopacity on panoramic radiograms. And 141 cases (31.6％) showed apparent increased radiopacity and 133 cases(33.4％) showed suspicious increased radiopacity on periapical radiograms.

• 소성∙가공
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• 제25권4호
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• pp.227-234
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• 2016

In the transportation between countries using container, too many empty containers must be transported due to the transportation unbalance. For transportation efficiency, therefore, foldable containers are being developed. Hinge brackets are important parts of foldable containers because great force is applied on the hinges during loading onto and unloading from ships. In this study, the hinge bracket for a foldable container is designed to be made using thick plate or bulk materials to endure the heavy loads. The forming process for the hinge bracket using a thick plate is designed via numerical analysis. First of all, the shape of bracket is designed for the better formability. Bending and successive side wall thickening processes are employed for the forming of the hinge bracket. Maximum thickening that can be achieved in a single stage of forming without a folding defect is determined and three stage of thickening processes are designed.

• Korea-Australia Rheology Journal
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• 제15권3호
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• pp.151-156
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• 2003

In this research, experimental studies were performed to examine the rheological behavior of equimolar solutions of cetylpyridinium chloride (CPyCl) and sodium salicylate (NaSal) solutions with concentration. The surfactant solutions were prepared by dissolving 2 mM/2 mM - 80 mM/80 mM of surfactant/counterion in double-distilled water. It has been observed that the zero shear viscosity shows abrupt changes at two critical values of C^*$ and C^{**}$. These changes are caused by the switching of relaxation mechanism with concentration of CPyCl/NaSal solutions at those concentrations. The wall slip velocities of dilute and semidilute CPyCl/NaSal solutions show a dramatic increase with shear rate where the shear viscosity exhibits shear thickening behavior for dilute solutions and shear thinning behavior for semi-dilute solutions, respectively. Considering that the dramatic increase in wall slip velocity should be related to the formation of shear-induced structure (SIS) in the surfactant solution, the shear thickening behavior of semi-dilute solutions is caused by elastic instability unlike the case of dilute solutions.

• Childhood Kidney Diseases
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• 제7권1호
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• pp.91-95
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• 2003

저자들은 4세에 신증후군으로 진단받고 스테로이드를 투여하며 재발을 수 회 반복하던 환자가 갑작스런 복통과 구토를 주소로 입원하여 시행한 검사 상 급성 무결석 담낭염으로 진단받고 금식, 비 위관 배액, 충분한 수액 공급, 그리고 항생제치료로 완치된 경우를 경험하였기에 이를 보고하는 바이다.

• 대한핵의학회지
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• 제32권1호
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• pp.1-9
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• 1998

Gated myocardial SPECT and attenuation correction gave birth to new insights into the pathophysiology of ischemic myocardial perfusion and function in clinical routine practice. Gated myocardial Tc-99m-compound SPECT improved diagnostic accuracy of coronary artery disease and enabled us to observe motion and thickening of myocardial walls as well as myocardial perfusion at the same time. Quantitative and qualitative assessment of myocardial performance and perfusion let us to understand the myocardial physiology in ischemia and infarction. In every patient who underwent gated perfusion SPECT, we will find ejection fraction, left ventricular volumes and regional wall motion. There are hopes to use gated TI-201 SPECT for the same purpose and to use gated SPECT for evaluation of wall motion and thickening at stress or immediate post-stress. Attenuation correction could improve diagnostic accuracy mainly by increasing normalcy ratio or performance of non-expert physicians. Both gated methods and attenuation correction improved specificity of non-expert physicians in diagnosing patients with moderate pretest likelihood. New imaging techniques will fill the desire of cardiologists to examine function and perfusion, and possibly metabolism in their clinical routine practice.