• Title/Summary/Keyword: patterns and treatment

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Teratological Evaluation of Azinphos-Methyl in Rat Fetuses (Azinphos-methyl이 랫트 태아에 미치는 기형학적 연구)

  • Cho, Myung-Haing;Lee, Chang-Eop;Lee, Yong-Soon
    • Toxicological Research
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    • v.4 no.1
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    • pp.55-84
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    • 1988
  • This study was carried out to investigate the teratological potential of azinphos-methyl in the rat fetuses and to establish the nature of the effects on organogenesis and intrauterine development. The Sprague-Dawley female rats (180-210g) without previous litter were used in this study. Azinphos-methyl dosages of 0.094mg/kg, 0.4mg/kg, 1.5mg/kg were selected based on the acute intragastric $LD_{50}$ of 15mg/kg in the rat. Azinphos-methyl in water (Treatment Group), non-treatment control (Negative Control), water control (Sham Control), were administered by oral route and aqueous solution of acetyl salicylic acid (Positive Control) was administered by gavage at rate of 10 ml/kg of body weight from day 6 through 15. The results obtained were summarized as follows. 1. Decreased body weight of dams was observed in animals treated with aspirin and azinphos-methyl 1.5 mg/kg from day 7 through 14. (P<0.01) 2. There was an apparent decrement in the absolute liver weight in the azinphos-methyl 1.5 mg/kg treated group (P<0.05). However, the absolute and relative kidney weight in aspirin group (P<0.05, P<0.01) and the absolute and relative ovary weight in aspirin, azinphos-methyl treatment groups (P<0.01, P<0.05) were increased. 3. Decreased protein contents of dam's liver was observed in the aspirin and high dose azinphos-methyl treated group of animals (P<0.01). 4. The number of male-female ratio per dam increased in azinphos-methyl 1.5 mg/kg group but there was an apparent decrement in the body weight of fetuses in aspirin and high dose azinphos-methyl group (P<0.01, P<0.05). Total immature and resorbed fetuses were increased in aspirin group and the number of dead fetuses were also increased in azinphos-methyl 1.5mg/kg treated group of animals. (P<0.01, P<0.05). 5. In soft tissue defects, diaphragmatic hernia in diaphragm, anophthalmia, enlarged olfactory bulb, hydrocephalus, absence of third and lateral ventricle in skull, hydronephrosis in kidney, atrophy of left ventricle wall, enlarged apex in heart were observed. Especially, defects of diaphragm, heart and eye ball showed peak incidences in the high dose azinphosmethyl and aspirin group. (P<0.01). 6. Variations in the ossification patterns of skull, sternebrae, tail, forelimbs and hindlimbs showed peak incidences in the aspirin and high dose azinphos-methyl group. (P<0.01). 7. In the developmental indices of offspring, the mortality of aspirin and azinphos-methyl 1.5mg/kg treated group was higher than that of negative control. And, there was an apparent decrement in the body weight of fetuses (P<0.01) and considerable differences were obtained in pivoting, development of fur, auditory function, vision, quadrupled muscle development and testes descent in aspirin and azinphos-methyl 1.5mg/kg group. (P<0.01).

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Gene Expression Profiling of SH-SY5Y Human Neuroblastoma Cells Treated with Ginsenoside Rg1 and Rb1 (Ginsenoside Rg1 및 Rb1을 처리한 신경세포주(SH-SY5Y세포)의 유전자 발현양상)

  • Lee, Joon-Noh;Yang, Byung-Hwan;Choi, Seung-Hak;Kim, Seok-Hyun;Chai, Young-Gyu;Jung, Kyoung-Hwa;Lee, Jun-Seok;Choi, Kang-Ju;Kim, Young-Suk
    • Korean Journal of Biological Psychiatry
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    • v.12 no.1
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    • pp.42-61
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    • 2005
  • Objectives:The ginsenoside Rg1 and Rb1, the major components of ginseng saponin, have neurotrophic and neuroprotective effects including promotion of neuronal survival and proliferation, facilitation of learning and memory, and protection from ischemic injury and apoptosis. In this study, to investigate the molecular basis of the effects of ginsenoside on neuron, we analyzed gene expression profiling of SH-SY5Y human neuroblastoma cells treated with ginsenoside Rg1 or Rb1. Methods:SH-SY5Y cells were cultured and treated in triplicate with ginsenoside Rg1 or Rb1($80{\mu}M$, $40{\mu}M$, $20{\mu}M$). The proliferation rates of SH-SY5Y cells were determined by MTT assay and microscopic examination. We used a high density cDNA microarray chip that contained 8K human genes to analyze the gene expression profiles in SH-SY5Y cells. We analyzed using the Significance Analysis of Microarray(SAM) method for identifying genes on a microarray with statistically significant changes in expression. Results:Treatment of SH-SY5Y cells with $80{\mu}M$ ginsenoside Rg1 or Rb1 for 36h showed maximal proliferation compared with other concentrations or control. The results of the microarray experiment yielded 96 genes were upregulated(${\geq}$3 fold) in Rg1 treated cells and 40 genes were up-regulated(${\geq}$2 fold) in Rb1 treated cells. Treatment with ginsenoside Rg1 for 36h induced the expression of some genes associated with protein biosynthesis, regulation of transcription or translation, cell proliferation and growth, neurogenesis and differentiation, regulation of cell cycle, energy transport and others. Genes associated with neurogenesis and neuronal differentiation such as SCG10 and MLP increased in ginsenoside Rg1 treated cells, but such changes did not occur in Rb1-group. Conclusion:Our data provide novel insights into the gene mechanisms involved in possible role for ginsenoside Rg1 or Rb1 in mediating neuronal proliferation or cell viability, which can elicit distinct patterns of gene expression in neuronal cell line. Ginsenoside Rg1 have more broad and strong effects than ginsenoside Rb1 in gene expression and related cellular physiology. In addition, we suggest that SCG10 gene, which is known to be expressed in neuronal differentiation during development and neuronal regeneration during adulthood, may have a role in enhancement of activity dependent synaptic plasticity or cytoskeletal regulation following treatment of ginsenoside Rg1. Further, ginsenoside Rg1 may have a possible role in regeneration of injured neuron, promotion of memory, and prevention from aging or neuronal degeneration.

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Studies on the Seroimmunodiagnosis of Parasitic Diseases (기생충질환(寄生蟲疾患)의 면역혈청학적(免疫血淸學的) 진단(診斷)에 관한 연구(硏究))

  • Rim, Han-Jong;Lee, Joon-Sang;Joo, Kyoung-Hwan;Eam, Kee-Seon;Chung, Myung-Sook
    • Journal of agricultural medicine and community health
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    • v.13 no.1
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    • pp.41-59
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    • 1988
  • In many of the helminthic infections, diagnosis is accomplished by the demonstration of the eggs or, occasionally the adult worms or their parts. Diagnosis can be made by the identification of larval stage obtained from stool or surgically extracted materials too. However some kinds of parasitic disease can not be diagnosed by above mentioned procedure alone. Brain cysticercosis, ectopic paragonimiasis, Capillaria hepatica infection in liver is a good example. In such a case, immunologic method would be helpful for the decision of physician. In this paper, immunologic tools such as indirect hemagglutination test, indirect fluorescent antibody test, circumoval precipitation test, ELISA, western blot were applied for the diagnosis of Clonorchis sinenisis, Cysticercosis and C. hepatica a infection and their efficacy was evaluated. The results obtained were as follows ; 1) In the diagnosis of clonorchiasis, ELISA revealed sensitiveity of 83.3%, but cross reaction against antibody of Paragonimus westermani and Taenia species were observed. For the identification of cross reaction and species specific band of Ag-Ab reaction, western blot was applied. 59Kd relative molecular weight and 21Kd band were identified as a Clonorchis sinensis specific band. OD values of ELISA performed with sera of 18 months after praziquantel treatment decreased to half level compared to that of before treatment. Negative conversion rate of ELISA after 18 months of treatment was 60%. 2) In the diagnosis of cysticercosis, IFAT disclosed 95.8%(23/24) of sensitivity and reaction was most strongly occurred in inner membrane. ELISA revealed 90.0% (36/40) of sensitivity, but cross reaction was observed in both technique. In western blot, 91, 63 and 21Kd Mw bands were identified as a strongly positive band. Among them 63Kd band showed positive reaction against almost all sera of cysticercosis patient. 3) Circumoval precipitation, ELISA, IFAT, showed 85.0% of sensitivity in the diagnosis of C. hepatica infection in rat. The antigenic localities were inner membrane of sectioned egg antigen on the prectipitates around the mucoid plugs which were induced by circumoval precipitation reaction. Sera from rats infected with 2000eggs were collected periodically to observe the changing patterns of antibody titers by IFAT and ELISA, which showed that high titers were detected at weeks 3 and 5, then gradually declined through weeks 9until to negatively converted at weeks 13.

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Acute Exacerbation of Idiopathic Pulmonary Fibrosis with Lung Cancer: A Comparative Analysis of the Incidence, Survival Rate, and CT Findings with the Patients without Lung Cancer (폐암을 동반한 특발성 폐섬유증 환자에서 폐섬유증의 급성 악화: 폐암 비동반군과의 발병률, 생존율 및 전산화단층촬영 소견의 비교)

  • Bumsang Cho;Hee Kang;Je Hun Kim;Jung Gu Park;Sekyoung Park;Jong Hyouk Yun
    • Journal of the Korean Society of Radiology
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    • v.81 no.3
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    • pp.688-700
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    • 2020
  • Purpose To compare the incidence, survival rate, and CT findings of acute exacerbation (AE) of idiopathic pulmonary fibrosis (IPF) between patients with and without lung cancer. Materials and Methods From June 2004 to July 2018, 89 consecutive patients diagnosed with IPF were included. Among them, 26 patients had IPF with lung cancer (IPF-LCA), and 63 patients had IPF alone. The clinical characteristics and CT findings associated with IPF, lung cancer, and AE were reviewed. Surgery and chemotherapy were performed for 6 and 23 cases of lung cancer, respectively, as the first- or second-line anticancer treatment. The overall survival, CT findings, disease-free period before AE, and duration from the onset of AE to death were compared. Results The incidence of AE was 61.5% in the IPF-LCA group and 58.7% in the IPF group (p = 0.806). The mean overall survival in the IPF-LCA and IPF groups were 16.8 and 83.0 months, respectively (p < 0.001). The mean durations from the start of the lung cancer treatment to the onset of AE were 16.0 and 4.6 months in cases of surgical treatment and chemotherapy, respectively. In comparison of death from AE, the survival rate was significantly lower in the IPF-LCA group than in the IPF group (p = 0.008). In the CT findings associated with AE, the IPF-LCA group tended to have a peribronchial (p < 0.001) or asymmetric distribution (p = 0.016). Conclusion In patients with IPF who develop lung cancer, the rate of death from AE is higher than that in patients with IPF alone. They tend to have unusual CT patterns associated with AE, such as a peribronchial or asymmetric distribution.

Combined Effects of Biological Control Agent Two Native Shellfish on the Hibernal Diatom Bloom of Eutrophic Water (저온기 규조 발생억제를 위한 패류의 혼합적용)

  • Lee, Song-Hee;Hwang, Soon-Jin;Kim, Baik-Ho
    • Korean Journal of Ecology and Environment
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    • v.41 no.3
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    • pp.402-411
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    • 2008
  • Grazing effects of two freshwater shellfish, Unio douglasiae (UNIO) and Cipangoplaudina chinese malleata (CCM), on the hibernal diatom communities in eutrophic water was examined in a laboratory. Two animals having different feeding types used in the study were collected from Keum River (Boryeong, Korea), acclimatized in the artificial management system in a laboratory over at least one month, and starved in a laboratory for 2 days before the experiment. Experimental waters, which dominated by Synedra ulna-Scenedesmus sp. (ca. 80%), was collected from eutrophic lake, Lake Ilgam (Seoul) in Feb., 19, 2008 at AM 10:00, and used in the study after the filtration with 1 mm Nylon mesh. Feeding experiments were largely divided into three kinds of animal treatments; five densities of UNIO (U0, U1, U2, U3, U4) and CCM (C0, C1, C2, C3, C4), and four combined densities of two shellfish (M0, M1, M2, M3). U0 and C0 were control (no addition of UNIO or CCM), U1 or C1 (each animal density at 0.5 ind. $L^{-1}$), U2 or C2 (1.0 ind. $L^{-1}$), U3 or C3 (1.5 ind. $L^{-1}$), and U4 or C4 (2.0 ind. $L^{-1}$), respectively. Four combined treatments were consisted of M0 (no animals), M1 (U1+C3), M2 (U2+C2), and M3 (U4+C1), respectively. Under the presence of animal, the concentration of Chl-a and algal abundance were clearly decreased with the increase of UNIO density and the treated time, while in combined group a strong decrease of algal density showed with the increase of UNIO density. Total phytoplankton density shifted as the similar patterns to that of Chl-a concentration (r=0.6527, p<0.0001), however, there showed the differences following a species. There were strong decreases of dominant species Synedra ulna, Scenedesmus sp., Ankistrodesmus falcatus in UNIO treatment group, Diatoma vulgare in combined group, while Cryptomonas ovata in high density of CCM increased about 20% in algal density. Grazing rates (GRs) based on the concentration of Chl-a was depend on the kind of shellfish and treatment time; a strong feeding of CCM showed in the initial stage, and four hours later, UNIO and combined group with high UNIO density showed the high GRs. Interestingly, faeces production of shellfish was highest in combined group with high density of CCM, while their size over 60 ${\mu}m$ was much higher in production magnitude than that less 60 ${\mu}m$. Collectively, these results suggest that two domestic shellfish and its combined treatment have a strong potential as an effective biological controller of diatom bloom in cold eutrophic waters.

An Analysis of Suitable site of Constructed Wetland using High Resolution Satellite Image and GIS in Kyoung-An Stream (고해상도 위성영상과 GIS를 이용한 인공습지 적지 분석 -경안천을 대상으로-)

  • Koh, Chang-Hwan;Jin, Do;Ha, Sung-Ryong
    • Journal of Wetlands Research
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    • v.10 no.2
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    • pp.115-128
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    • 2008
  • Various human activities such as the Urbanization and Industrialization are estimated the main factors to pollute the stream. Now days, numerous studies are carried out for managing non-point sources which have un-effect on water quality of streams by land-use and livestock. In case of Korea, a matter of concern that the management of Pal dang reservoir - the main water resources of the national capital region - has been occurring. Especially, large-scale constructed-wetlands are planned and constructed at the end of Kyoung-an stream. Additionally a lot of sewage treatment plants are newly installed and extended in this watershed. According to these efforts, water quality of Kyoung-an stream is predicted that would be improved. But the more detail and scientific analysis should be carried out for the water quality improvement, because, existing water quality improvement projects are not involved to analyze root of water quality deterioration and improvement plans. Therefore, this study aims to select suitable areas for constructed-wetlands and to calculate size of the constructed-wetlands for water quality improvement in Kyoung-an stream through the geographical pollutant distribution analysis and land-use pattern analysis by high resolution satellite image and suitable area analysis of constructed-wetlands by GIS(Geographic information system). The progress of this study is (1) to select maximum pollutant loaded area by geographical analysis based on water quality data, (2) to analyze land-use patterns using high resolution satellite image, (3) to select suitable areas of constructed-wetlands, (4) to calculate area and volume of chosen constructed-wetlands using GIS. Basically, sizes of constructed-wetlands are induced through the constructed-wetlands design index based on treatment ratio(provided by Korea Water Resources Corporation). As a result of this study, two areas are selected to construct constructed-wetlands. One of the area was $127,586m^2$ near by Yong-in sewage treatment plant, and the other area was $1,647m^2$ near by Ju-buk stream and Dae-dae stream.

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Comparison of the Therapeutic Effects of $Curosurf^{(R)}$ and $Newfactan^{(R)}$ in Respiratory Distress Syndrome (신생아 호흡 곤란 증후군에서 $Curosurf^{(R)}$$Newfactan^{(R)}$의 치료 효과 비교)

  • Hong, Suk-Woo;Lee, Eun-Ho;Kim, Seung-Yeon;Park, Ho-Jin
    • Neonatal Medicine
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    • v.15 no.2
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    • pp.142-151
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    • 2008
  • Purpose : The aim of this study was to compare the clinical effects of modified porcine (Curosurf$^{(R)}$) and bovine (Newfactan$^{(R)}$) surfactants in the treatment of neonatal respiratory distress syndrome. Methods : Between April 2004 and December 2006, 65 neonates (birth weight ${\leq}$2,500 g and gestational age ${\leq}$35 weeks) with neonatal respiratory distress syndrome were treated in our neonatal intensive care unit with surfactant. Thirty-one neonates received Curosurf$^{(R)}$ and 34 neonates received Newfactan$^{(R)}$. The neonates were not enrolled if they had major congenital anomalies or meconium aspiration syndrome. We compared the changes in respiratory parameters after surfactant instillation, the incidences of acute and chronic complications, and the mortality between the two treatment groups. Results : Neonatal and maternal demographic characteristics were not different between the groups. The patterns of change in the respiratory parameters after surfactant instillation were not statistically different between the groups. The incidences of surfactant reinstillation and acute complications, such as pneumothorax, patent ductus arteriosus, pulmonary hemorrhage, and grade 3-4 intraventricular hemorrhage, were not different between the neonates who received Curosurf$^{(R)}$ and the neonates who received Newfactan$^{(R)}$. There were no statistically significant differences in the duration of mechanical ventilation, oxygen therapy, hospitalization, prevalence of bronchopulmonary dysplasia, periventricular leukomalacia, retinopathy of prematurity, necrotizing enterocolitis, and mortality between the groups. Conclusion : In the present comparative study, no significant differences in the clinical effects of Curosurf$^{(R)}$ and Newfactan$^{(R)}$ were observed.

Ecophysiological Studies on the Water Relations of Economic Tree Species - Temporal Changes of Stomatal Responses to Soil Moisture Regimes and Exogenous Abscisic Acid in Oaks and Ash - (주요 경제 수종의 수분 특성에 관한 생리생태학적 연구 - 토양수분 조건 및 ABA 처리에 따른 참나무류와 물푸레나무 기공의 시계열적인 변화 반응 -)

  • Kwon, Ki Won;Lee, Jeoung Ho
    • Journal of Korean Society of Forest Science
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    • v.83 no.3
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    • pp.410-423
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    • 1994
  • Seasonal and diurnal changes of stomatal diffusive resistance(S.D.R.) and transpiration rate(T.R.) were investigated for determining the ecophysiological water relations of economic tree species subjected to chronic water stress or exogenous abscisic acid treatment. Four species of oaks including Quercus serrata, Q. mongolica. Q. acutissima, and Q. variabilis were used as the experimental materials and also Fraxinus rhynchophylla was studied together with oaks. Stomatal diffusive resistances were repeatedly measured on the containerized 1-0 year seedlings subjected to two kinds of soil moisture regime (wet and dry) in June, August, and September by LI-1600 Steady State Porometer of LI-Cor, Inc.. Exogenous abscisic acid (ABA) solutions of 0.5 mM and 0.05 mM in July and August, respectively, were absorbed into shoots cut from the containerized seedlings for determining their effects on stomatal behavior and transpiration. Most of measurements in stomatal diffusive resistance maintained about 5 s/cm in the morning after sunrise despite of different treatments. But the values fluctuated frequently to high level above 20 s/cm through the afternoon until sunset in the seedlings subjected to dry soil moisture regime. Despite of various treatments and environmental conditions, stomatal diffusive resistances of Q. variabilis were more stable than those of Q. serrata or Q. acutissima. Their values of F. rhynchophylla changed more irregularly in comparison with those of oak species. Exogenous abscisic acid absorbed into shoots cut from seedlings increased stomatal diffusive resistance obviously in most of the species studied. The stomatal responses to abscisic acid treatment were more sensitive in July especially in Q. serrata than in Q. variabilis and Q. acutissima. But the effects of ABA treatment were presented more remarkably in Q. acutissima in August. The responses to abscisic acid were not certain in F. rhynchophylla because of their various fluctuation patterns.

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Primary Orbital Lymphoma : A Retrospective Analysis of Results of Radiation Therapy (원발성 안와 림프종의 방사선치료 성적에 관한 후향적 분석)

  • Kim Sussan;Ahn Seung Do;Chang Hyesook;Kim Kyoung Ju;Lee Sang-wook;Choi Eun Kyung;Kim Jong Hoon;Huh Jooryung;Suh Cheol Won;Kim Sung Bae
    • Radiation Oncology Journal
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    • v.20 no.2
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    • pp.139-146
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    • 2002
  • Purpose : This study evaluated the treatment outcomes, patterns of failure, and treatment related complications of primary lymphoma patients who received definitive radiation therapy. Materials and Methods : A retrospective analysis was undertaken for 31 patients with primary orbital lymphoma at the Asan Medical Center between February 1991 and April 2001. There were 18 males and 13 females with ages ranging from 3 to 73 years (median, 44 years). The involved sites were 9 conjunctivae, 12 eyelids and 10 other orbits. The histological types were 28 MALT lymphomas (low-grade B-cell lymphoma of mucosa-associated lymphoid tissue type), 1 diffuse large B-cell lymphoma, 1 anaplastic large cell lymphoma and 1 lymphoblastic lymphoma. The Ann Arbor stages were all IE $(100\%)$. Ann Arbor stage III or IV patients were excluded from this study, Bilateral orbital involvement occurred in 6 cases. Radiation therapy was given with one anterior port of high energy electrons $(6\~16\;MeV)$ for the lesions located at the anterior structures like the conjunctivae or eyelids. Lesions with a posterior extension or other orbital lesions were treated with 4 or 6 MeV photons with appropriately arranged portals. In particular, lens blocks composed of lead alloy were used in conjunctival or eyelid lesions. Twelve patients received chemotherapy. The median follow-up period was 53 months. Results : The 5-year overall, cause-specific, and disease-free survival was $91\%,\;96\%,\;and\;80\%$, respectively. The complete response rate 6 months after radiation therapy was $100\%$. Local recurrences were observed in 2 patients at 16 and 18 months after completion of radiation treatment. They were salvaged with additional radiation therapy. Two patients developed distant metastases. A MALT lymphoma patient with a lung relapse was successfully salvaged with radiotherapy, but the other lymphoblastic lymphoma patient with bone marrow relapse expired. There were no severe complications but 5 patients developed radiation-induced cataracts and 2 patients developed dry eye. Conclusion : Most primary orbital lymphomas consisted of MALT lymphomas. Radiation therapy was a successful treatment modality for orbital lymphoma without any severe complications. In cases of local relapses, radiation therapy is also a very successful salvage treatment modality.

A Study about the Change of Locations of the Center of Resistance According to the Decrease of Alveolar Bone Heights and Root Lengths during Anterior Teeth Retraction using the Laser Reflection Technique (Laser 반사측정법을 이용한 전치부 후방 견인시 치조골 높이와 치근길이 감소에 따른 저항중심의 위치변화에 관한 연구)

  • Min, Young-Gyu;Hwang, Chung-Ju
    • The korean journal of orthodontics
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    • v.29 no.2 s.73
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    • pp.165-181
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    • 1999
  • Treatment mechanics should be individualized to be suitable for each patient's personal teeth and anatomic environment to get a best treatment result with the least harmful effects to teeth and surrounding tissues. Especially, the change of biomechanical reaction associated with that of the centers of resistance of teeth should be considered when crown-to-root ratio changed due to problematic root resorption and/or periodontal disease during adult orthodontic treatment. At the present study, in order to investigate patterns of initial displacements of anterior teeth under certain orthodontic force when crown-to-root ratio changed in not only normal periodontal condition but also abnormal periodontal and/or teeth condition, the changes of the centers of resistance for maxillary and mandibular 6 anterior teeth as a segment were studied using the laser reflection technique, the lever & pulley force applicator and the photodetector with these quantified variables reducing alveolar bone 2mm by 2mm for each of maxillary 6 anterior teeth until the total amount of 8mm and root 2mm by 2mm for each of mandibular 6 anterior ones until the total amount of 6mm. The results were as follows: 1. Under unreduced condition, the center of resistance during initial displacement of maxillary 6 anterior teeth was located at the point of about $42.4\%$ apically from cemento-enamel junction(CEJ) of the averaged tooth of them and kept shifting to about $76.7\%$ with alveolar bone reduction. 2. The distance from the averaged alveolar crest level of maxillary 6 anterior teeth to the center of resistance for the averaged tooth of them kept decreasing with alveolar bone reduction, but the ratio to length of the averaged root embedded in the alveolar bone was stable at around $33\%$ regardless of that. 3. Under unreduced condition, the center of resistance during initial displacement of mandibular 6 anterior teeth was located at the Point of about $43\%$ apically from CEJ of the averaged tooth of them and this ratio kept increasing to about $54\%$ with root reduction. But the distance from CEJ to the center of resistance decreased from around 5.3mm to around 3.3mm, that is to say, the center of resistance kept shifting toward CEJ with the shortening of root length. 4. A unit reduction of alveolar bone had greater effects on the change of the centers of resistance than that of root did during initial Phase of each reduction. But both of them had similar effects at the middle region of whole length of the averaged root.

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