• Title/Summary/Keyword: pitting

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A case of Pulmonary Veno-occlusive Disease (폐정맥 패쇄에 의한 폐고혈압증 1예)

  • Cho, Jae-Youn;Lee, Sang-Youb;Lee, Sang-Hwa;Park, Sang-Myeon;Suh, Jeong-Kyung;Shim, Jae-Jeong;In, Kwang-Ho;Kang, Kyung-Ho;Yoo, Se-Hwa;Kim, Kwang-Taek
    • Tuberculosis and Respiratory Diseases
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    • v.43 no.2
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    • pp.274-279
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    • 1996
  • Pulmonary veno-occlusive disease is a rare cause of pulmonary hypertension in which the primary abnormality is obliterative obstruction of pulmonary veins, especially venules. Clinicaly, we should suspect this disease in the case of congestive cardiac failure with pulmonary hypertension, chronic interstitial pulmonary edema, and normal or elevated wedge pressure on cardiac catheterization. We experience a case of pulmonary hypertension due to pulmonary veno-occlusive disease. A 55-years -old woman developed progressive dry cough and dyspnea for 3 months. Physical examination showed normal heart sounds, diffuse crackles in the whole lung fields. The liver was not palpable and pitting edema was absent. The diagnosis was made by chest HRCT, 2-D echocardiography, normal pulmonary capillary wedge pressure on cardiac catheterization, and confirmed by thoracoscopic lung biopsy. This patient was treated with vasodilator(calcium antagonist) and with mild symptomatic improvement. We reported a case of pulmonary veno-occlusive disease with review of literatures.

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AN ELECTROCHEMICAL STUDY ON THE CORROSION RESISTANCE OF THE VARIOUS IMPLANT METALS (수종 임플랜트 금속의 내식성에 관한 전기화학적 연구)

  • Jeon Jin-Young;Kim Yung-Soo
    • The Journal of Korean Academy of Prosthodontics
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    • v.31 no.3
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    • pp.423-446
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    • 1993
  • Titanium and its alloys are finding increasing use in medical devices and dental implants. The strong selling point of titanium is its resistance to the highly corrosive body fluids in which an implant must survive. This corrosion resistance is due to a tenacious passive oxide or film which exists on the metal's surface and renders it passive. Potentiodynamic polarization measurement is one of the most commonly used electro-chemical methods that have been applied to measure corrosion rates. And the potentiodynamic polarization test supplies detailed information such as open circuit, rupture, and passivation potential. Furthermore, it indicates the passive range and sensitivity to pitting corrosion. This study was designed to compare the corrosion resistance of the commonly used dental implant materials such as CP Ti, Ti-6A1-4V, Co-Cr-Mo alloy, and 316L stainless steel. And the effects of galvanic couples between titanium and the dental alloys were assessed for their useful-ness-as. materials for superstructure. The working electrode is the specimen , the reference electrode is a saturated calomel electrode (SCE), and the counter electrode is made of carbon. In $N_2-saturated$ 0.9% NaCl solutions, the potential scanning was performed starting from -800mV (SCE) and the scan rate was 1 mV/sec. At least three different polarization measurements were carried out for each material on separate specimen. The galvanic corrosion measurements were conducted in the zero-shunt ammeter with an implant supraconstruction surface ratio of 1:1. The contact current density was recorded over a 24-hour period. The results were as follows : 1. In potential-time curve, all specimens became increasingly more noble after immersion in the test solution and reached between -70mV and 50mV (SCE) respectively after 12 hours. 2. The Ti and Ti alloy in the saline solution were most resistant to corrosion. They showed the typical passive behavior which was exhibited over the entire experimental range. Therefore no breakdown potentials were observed. 3. Comparing the rupture potentials, Ti and Ti alloy had the high(:st value (because their break-down potentials were not observed in this study potential range ) followed by Co-Cr-Mo alloy and stainless steel (316L). So , the corrosion resistance of titanium was cecellent, Co-Cr-Mo alloy slightly inferior and stainless steel (316L) much less. 4. The contact current density sinks faster than any other galvanic couple in the case of Ti/gold alloy. 5. Ag-Pd alloy coupled with Ti yielded high current density in the early stage. Furthermore, Ti became anodic. 6. Ti/Ni-Cr alloy showed a relatively high galvanic current and a tendency to increase.

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Anatomical Comparison of Compression, Opposite, and Lateral Woods in a Branch of Pinus parviflora S. et Z. (섬잣나무(Pinus parviflora S. et Z.) 지재의 압축이상재, 측면재, 대응재에 관한 해부학적 특성 비교)

  • Xu, Guang Zhu;Eom, Young Geun
    • Journal of the Korean Wood Science and Technology
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    • v.33 no.1 s.129
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    • pp.38-47
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    • 2005
  • Compression, lateral, and opposite woods in a branch of Pinus parviflora S. et Z. were described and compared in the qualitative anatomical aspects through light and scanning electron microscopy. Tracheid transition from earlywood to latewood in the compression wood appeared to be relatively more gradual than in the opposite or lateral wood. Growth ring width and proportion of latewood were thought to be greater in the compression wood than in the lateral or opposite wood. The latewood tracheids of compression wood in transverse surface were mostly round, differently from those of lateral and opposite woods with square to angular shapes. Also, intercellular spaces, helical cavities and checks, and slit-like pit apertures were observed only in the compression wood tracheids. Cross-field pitting in the compression wood appeared not to be used as diagnostic guide because of their severe alteration from normal fenestriform or window-like type to cupressoid to taxodioid types. In tangential surface, fusiform rays in the compression wood were wider but lower than those in the lateral wood or opposite wood. In conclusion, compression wood was different from lateral and opposite woods but lateral and opposite woods were almost identical in qualitative anatomical features.

Giant Magnetoresistance of Antiferromagnetic Cr-Al based Multilayer Spin-Valve with Anti-Corrosion and Thermal Stability (내열 내식용 Cr-Al반강자성계 스핀밸브막의 거대자기저항 효과)

  • 김병수;이성훈;이찬규
    • Journal of the Korean Magnetics Society
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    • v.8 no.6
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    • pp.362-368
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    • 1998
  • The magnetic properties, thermal stability and anti-corrosion properties of $Cr_86Al_14$ spin valves multilayers were studied. It was found that the magnetic properties of $Cr_86Al_14$ spin valves depend on the thickness of antiferromagnetic, ferromagnetic and non-ferromagnetic layers. Exchange coupled field ($H_{ex}$) and magnetoresistance ratio (%) showed the largest value of 20 Oe, 2 % in $glass/Cr_{86}Al_{14}(600 $\AA$)/Ni_{81}Fe_{19}(50$\AA$)/Cu(40 $\AA$)/Ni_{81}Fe_{19}(40 $\AA$)$ spin valves. The $H_{ex}$ MR ratios (%) of CrAl and FeMn spin valves were decreased with increasing annealing temperatures and were lost at 150 $^{\circ}C$, 250 $^{\circ}C$ respectively. Based on these result, it was elucidated that CrAl is more thermally stable than FeMn. It was also shown that there was no change of $H_{ex}$ MR ratios in CrAl, while FeMn was changed and lost 15 days later in corrosion resistance test under 35 $^{\circ}C$, 90 % humidity condition. FeMn was found to be pitted and peeled off 15 days later by SEM micrographic analysis.

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Comparison of Virus Elimination Methods for Disease-free Seedlings of the Apple Dwarfing Rootstock (사과 왜성대목 무독묘 생산을 위한 바이러스 제거 방법 비교)

  • Kwon, Young Hee;Lee, Joung Kwan;Kim, Hee Kyu;Kim, Kyung Ok;Park, Jae Seong;Huh, Yoon Sun;Yoon, Yeo Joong
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2019.04a
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    • pp.54-54
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    • 2019
  • Apple (Malus domestica) is one of the most economically important fruits in Korea. But virus infection has decreased sustainable production of apple and caused the serious problems such as yield loss and poor fruit quality. Virus or viroid infection including Apple chlorotic leaf spot virus (ACLSV), Apple stem pitting virus (ASPV), Apple stem grooving virus (ASGV), Apple mosaic virus (ApMV) and Apple scar skin viroid (ASSVd) has been also reported in Korea. In many cases, apple is infected with virus and viroid with no specific symptoms, the damage caused by the virus are unaware significantly. In our research, we tried to eliminate viruses in the rootstock for the disease-free seedlings of the apple dwarfing rootstock M.9 and M.26. The method of virus elimination was meristem culture, heat($37^{\circ}C$, 6weeks) treatment and chemistry($Ribavirin^{(R)}$) treatment. The analytical methods commonly used for the detection of virus is Enzyme-linked Immuno-Sorbent Assay(ELlSA) and Reverse Transcription-polymerase Chain Reaction(RT-PCR). RT-PCR method was more 30% sensitive than ELISA method. Efficiency of method eliminate virus appeared meristem method > heat treatment > chemistry treatment. The higher acquisition rate of disease-free seedlings is 30~40% on meristem treatment. In meristem treatment, the apple dwarfing rootstock M.9 gained infection ratio of ACLSV, ASPV and ASGV were 45%, 60% and 50% respectively. In the apple dwarfing rootstock M.26, infection ratio of ACLSV, ASPV and ASGV were 40%, 55%, 55%, respectively. Based on our results, it was found that most effective method of disease-free seedlings apple dwarfing rootstocks was by meristem treatment than heat method and chemistry treatment.

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A Study on Titanium Miniscrew as Orthodontic Anchorage : An experimental investigation in dogs (성견에서 교정적 고정원으로서의 티타늄 미니스크류에 대한 연구)

  • Yoon, Byung-Soo;Choi, Byung-Ho;Lee, Won-You;Kim, Kyoung-Nam;Shim, Hyung-Bo;Park, Jin-Hyung
    • The korean journal of orthodontics
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    • v.31 no.5 s.88
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    • pp.517-523
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    • 2001
  • Titanium miniscrews we being used increasingly as an anchorage for tooth movement, because they ate easy to place and to remove, increase the number of sites available, give minimum strain to patients regarding surgical procedures, and offer uneventful healing alter removal. The use of titanium miniscrews as an orthodontic anchorage has been reported in clinical case reports, but clinicians have experienced screw loosening when using such screws.' To our knowledge, there are no published reports evaluating the stability of miniscrews. Information about the length of miniscrews used in relation to the location is of some importance, as stability will vary depending on bone duality The purpose of this study was to evaluate a variety of Lengths of miniscrews (dimeter: 2mm) which were inserted in maxilla or mandible and to demonstrate in a dog model which miniscrew provides fundamental stability in the jaws. 10 mm long miniscrews in the maxilla and 8mm long: miniscrews in the mandible showed no clinical mobility and retained their position throughout an 8 weeks force (200g) application. The mucosal condition around the screws was healthy in cases in which miniserews were inserted in the alveolar bone between the roots and the head of the screws emerged into the attached gingiva. When the force application was terminated, radiographic analysis revealed neither rent resorption not periodontal pathology around the miniscrews that remained stable during the entire treatment period. This study suggests that if titanium miniscrews with adequate length are properly used depending on the location, they provide sufficient stability for orthodontic anchorage.

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Assessment of the permanent canine bone support after secondary bone graft In UCLP patients (편측성 순구개열 환자에서 이차 골이식후 맹출된 영구 견치의 치조골 지지도에 관한 연구)

  • Park, Ki-Tae
    • The korean journal of orthodontics
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    • v.31 no.6 s.89
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    • pp.601-610
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    • 2001
  • The purpose of this retrospective study was to evaluate the level oi alveolar bone support of the erupted Permanent canine through the reconstructed cleft region compared to the contralateral canine on the non-cleft side. This study was limited to children with complete unilateral cleft lip and palate who underwent secondary alveolar iliac bone gvaft and the apices of the erupted canine roots were closed at the time of evaluation. With these criteria the study included 21 children whose average age at the time of bone graft reconstruction was 9.8 years, with a minimum of 12.4 years of age at the time of the evaluation. The study was limited to the use of iliac cancellous bone as the autograft material for reconstruction of the alveolar cleft. Cranial bone graft and other autogenous bone sources were excluded. The periapical radiographs were used to evaluate alveolar bone level of each canine. The percentages of root supported by the bone were established by dividing the amount of root covered with the bone by the anatomic root length. The canine oi the non-cleft side was used as an internal control and the canine on the cleft side was used as an experimental. There was a statistically significant difference in the alveolar bone support ratio between the control ($92.9\%$) and experimental canines ($8.7\%$). An average of $95\%$ level of alveolar bone support was achieved for the experimental canine in comparison to the control canine. Neither the presence of lateral incisor, nor the stage of root development of the canine at the time of the bone graft appeared to have affected the alveolar bone support ratio of the canine after the secondary bone graft.

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Geochemical exploration for REE occurrence in Nghe An Area within Northern Vietnam (베트남 북부 네안 희토류 산출지의 지구화학탐사)

  • Heo, Chul-Ho;Chung, Ho Tien;Lee, Jae-Ho
    • Economic and Environmental Geology
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    • v.45 no.6
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    • pp.599-622
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    • 2012
  • The phase I soil geochemical exploration was carried out targeting around Chau Binh area far from about 14 km with southeastern direction from Quy Chau within Nghe An province. The interval of sampling are horizontal 300 m with 14 line and longitudinal 500 m with 15 line, resulting in 194 soil samples. Based on the result of the phase I soil geochemical exploration, the phase II detailed pitting survey was carried out targeting the grid point with high TREO content, resulting in 56 soil samples within 7 pits. The geology of survey area are consisted of Ban Chieng biotite granite complex and Dai Loc gneissic granite complex intruding Bu Khang formation comprising of schist, gneiss and limestone. Main mineralization in the study area have the characteristics of occurrence with tin, ruby and REE-bearing monazite(about 300 g/t) and xenotime(about 10 g/t) to be thought as occurring at the alteration zone of granite complex. In order to elucidate the source rock of monazite and xenotime confirmed from heavy sand, soil geochemical exploration was carried out. As a analysis result with ICP-MS on the soil samples from the phase I soil geochemical exploration, total REE oxide content of background amount to about 2 times of crustal abundance, enriching the heavy rare earth(about 2 times) and light rare earth(about 1.84 times). As a analysis result with ICP-MS on the soil samples from the phase II soil detailed pit survey, we identified outcrop considering as economic ore body at the grid point 4-7 pit with N40W attitude. As a synthetic consideration on the phase I soil geochemical exploration and phase II detailed pit survey, we tentatively designated areas considering as the extension of economic ore body with REE anomaly. In the near future, we have the plan to carry out the geophysical exploration and test drilling targeting the interval anticipated to the economic ore body.

Geochemical Exploration for Tri Le REE Occurrence in Nghe An Province within Northern Vietnam (베트남 북부 네안성 칠레 희토류 산출지의 지구화학탐사)

  • Heo, Chul-Ho;Ho, Tien Chung;Lee, Jae-Ho
    • Economic and Environmental Geology
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    • v.47 no.2
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    • pp.147-168
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    • 2014
  • The soil geochemical exploration was carried out targeting around Tri Le area far from about 30 km with northwestern direction from Que Phong within Nghe An province. The interval of sampling are horizontal 200 m interval with 23 line and longitudinal 300 m with 10 line, resulting in 228 soil samples. Based on the result of the soil geochemical exploration, the detailed pitting survey was carried out targeting the grid point with high TREO content, resulting in 75 soil samples within 7 pits. The geology of survey area are consisted of Ban Chieng biotite granite complex and granitic gneiss intruding Ban Khang formation comprising of quartz schist and marble. Main mineralization in the study area have the characteristics of occurrence with tin, ruby and REE-bearing monazite and xenotime to be thought as occurring at the alteration zone of granite complex. In order to elucidate the source rock of monazite and xenotime confirmed from heavy sand, soil geochemical exploration was carried out. As a analysis result with ICP-MS on the soil samples from the soil geochemical exploration, total REE oxide content of background amount to about 2 times of crustal abundance, enriching the heavy rare earth(about 2 times) and light rare earth(about 1.5 times). As a analysis result with ICP-MS on the soil samples from the soil detailed pit survey, we only identified outcrop considering as economic weathered granite body at the grid point 1-10 pit among 7 pits. As a synthetic consideration on the soil geochemical exploration and detailed pit survey, we tentatively designated Tri Le area as no promising target for REE. In 2014, we have the plan to carry out the soil geochemical exploration targeting the extended economic REE ore body in Quy Chau as project area from 2011 to 2012.

Immediate Effect of Hemodialysis on Pulmonary Function and Bronchodilator Response in Patients with Chronic Renal Failure (만성신부전 환자에서 혈액투석이 폐기능 및 기관지확장제에 대한 반응에 미치는 영향)

  • Jeon, Ho Seok;Lee, Yang Deok;Cho, Yongseon;Han, Min Soo
    • Tuberculosis and Respiratory Diseases
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    • v.56 no.1
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    • pp.77-84
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    • 2004
  • Background : We hypothesized that there was a relationship between body weight change and bronchodilator response (BDR) in patients with chronic renal failure (CRF) on hemodialysis (HD). Several mechanisms such as pulmonary edema due to water retention or increased permeability of alveolar capillary may play a important role in pulmonary function impairment and bronchial hyperresponsiveness in patients with CRF on HD. But, no studies have been published concerning BDR in patients with CRF on HD. This study was aimed to know the immediate effect of hemodialysis on pulmonary function and BDR in patients with CRF on HD. Methods : This study included 30 patients with CRF on HD. We collected data including age, sex, height, pretibial and pedal pitting edema, interdialysis weight gain, postdialysis weight loss, underlying diseases, duration of HD, $FEV_1$, FVC, $FEV_1/FVC$, and BDR before and after HD. Results : Interdialysis weight gain of the patients was $3.4{\pm}1.0kg$, and postdialysis weight loss was $3.2{\pm}0.7kg$. Before HD,$FEV_1$, FVC, and $FEV_1/FVC$ of the patients were $89{\pm}22%$, $86{\pm}19%$ of predicted, and $87{\pm}10%$. After bronchodilator inhalation, these parameters were changed to $95{\pm}22%$, $90{\pm}19%$ of predicted, and $88{\pm}9%$ respectively. BDR was positive in 15 patients. After HD, $FEV_1$, FVC, and $FEV_1/FVC$ of the patients were $100{\pm}23%$, $94{\pm}18%$ of predicted, and $88{\pm}11%$. After bronchodilator inhalation, these parameters were changed to $102{\pm}23%$, $96{\pm}18%$ of predicted, and $89{\pm}8%$ respectively. BDR was positive in 9 patients. Conclusion : First, HD increases $FEV_1$, FVC, and $FEV_1/FVC$ but little affects BDR. Second, there is no correlation between postdialysis weight loss and increases in $FEV_1$, FVC, and $FEV_1/FVC$ after HD. Third, there is also no correlation not only between interdialysis weight gain and BDR before HD but between postdialysis weight loss and BDR after HD.