• The Plant Pathology Journal
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• v.29 no.3
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• pp.260-273
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• 2013

The incidence and distribution of Tobacco mosaic virus (TMV) and related tobamoviruses was determined using an enzyme-linked immunosorbent assay on 1,926 symptomatic horticultural crops and 107 asymptomatic weed samples collected from 78 highly infected fields in the major horticultural crop-producing areas in 17 provinces throughout Iran. The results were confirmed by host range studies and reverse transcription-polymerase chain reaction. The overall incidence of infection by these viruses in symptomatic plants was 11.3%. The coat protein (CP) gene sequences of a number of isolates were determined and disclosed to be a high identity (up to 100%) among the Iranian isolates. Phylogenetic analysis of all known TMV CP genes showed three clades on the basis of nucleotide sequences with all Iranian isolates distinctly clustered in clade II. Analysis using the complete CP amino acid sequence showed one clade with two subgroups, IA and IB, with Iranian isolates in both subgroups. The nucleotide diversity within each subgroup was very low, but higher between the two clades. No correlation was found between genetic distance and geographical origin or host species of isolation. Statistical analyses suggested a negative selection and demonstrated the occurrence of gene flow from the isolates in other clades to the Iranian population.

• Korean Journal of Veterinary Research
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• v.44 no.3
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• pp.449-454
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• 2004

Ninety pigs under the age of 120-day-old requested at the diagnostic laboratory of animal diseases in Cheju National University were evaluated for the prevalence of tissue antigen and serum antibody to swine influenza virus (SIV). For histopathologic examination there was sampled at the consolidated area in cranioventral or dorsocaudal lobes of lungs. Lung tissues from all pigs were tested for the antigen of SIV type A by immunohistochemistry (IHC). Sera from 56 pigs were used for the antibody detection to SIV type A (subtype H1N1 and H3N2) by haemagglutinin inhibition test. Pneumonic lesions were observed in 72 cases (80%) of 90 pigs. Broncho-interstitial or interstitial pneumonia were more prevalent than suppurative or fibrinous bronchopneumonia. According to HI test, 46.4% of the tested sera showed seropositive. Positive sera were consisted with 5.3% for SIV H1N1, 28.6% for SIV H3N2, and 12.5% for both subtype to be tested, respectively. SIV antigens were detected in 51 cases(56.6%) of 90 pigs. Most SIV antigens were presented in the epithelium of the bronchi and bronchiole. Necrotizing bronchitis or bronchiolitis were observed in 28(31.1%) cases of all inspected pigs. These results suggested that SIV might be an important role to induce swine pneumonia in Jeju. Also IHC was very useful for the detection of SIV in the lung.

• Korean Journal of Veterinary Research
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• v.45 no.3
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• pp.391-398
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• 2005

Several studies have been performed on the bovine leukemia since bovine leukemia virus (BLV) had been detected in 1982 in Korea. We have conducted histopathological study on the bovine lymphoma caused by BLV because only limited results were reported on the pathological characterization of lymphoma. Lymphoma tissues were obtained from cattle necropsied and slaughtered during a designated period. Lymphoma was classified histopathologically according to the National Cancer Institute Working Formulation. Leukotic tissues consisted of fairly uniform sheets of closely packed medium to large lymphocytes without any architectural arrangement in all 30 cases. Twenty five cases belong to diffuse large cell type, while three cases were diffuse mixed cell type, and two cases were immunoblastic large cell type among 30 cases. Follicular type lymphoma was not detected in this study. The mitotic index of tumor cells showed average 2.5 in the field of 400X. Nuclear cleavage was detected in 53% of cases. Multi-nucleated cells were detected among tumor cells in 30% of lymphoma cases. In conclusion, the most common morphologic cell type of bovine lymphoma in Korea was a diffuse large cell type with multinucleated cells and nuclear cleavages.

• Clinical and Experimental Pediatrics
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• v.62 no.11
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• pp.422-427
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• 2019

Background: Polyomavirus BK (BKV) infection is an important cause of graft loss in kidney transplant patients. Purpose: The purpose of this study was to evaluate clinical findings and risk factors for BKV in pediatric patients after kidney transplantation. Methods: This retrospective single-center study included 31 pediatric kidney transplant recipients from January 2002 to December 2017. Two patients received 2 transplantations during the study period, and each transplant was analyzed independently. Total number of cases is 33 cases with 31 patients. BKV infection was confirmed from blood samples via periodic quantitative polymerase chain reaction. Results: The mean age at kidney transplantation was 11.0±4.7 years, and the male-to-female ratio was 2.7:1. Three patients had a past medical history of high-dose chemotherapy and autologous stem-cell transplantation for solid tumors. Nine patients (27.3%) developed BKV infection. The median period from kidney transplantation to BKV detection in blood was 5.6 months. There was no statistically significant difference in estimated glomerular filtration rate between patients with and those without BKV infection. Among 9 patients with BKV viremia, 7 were treated by reducing their immunosuppressant dose, and BKV was cleared in 6 of these 7 patients. In the other 2 BKV-positive patients, viremia improved without immunosuppressant reduction. Conclusion: BKV infection is common in children with kidney transplantation and might not have affected short-term renal function in our patient sample due to early immunosuppressant reduction at the time of BKV detection.

• Korean journal of applied entomology
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• v.5_6
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• pp.9-18
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• 1968

Morphological studios on the mouth parts of some aphids belonging to 5 sub-families and on the penetration of stylets into their host plants were carried out in order to find out possible relationship between mouth parts and capability of virus transmission. 1. There were no differences between the aphid species in general morphology of mouth parts. 2. Mouth parts could be observed in detail especially in Toxoptera citricidus and Chaitophorus chinensis. 3. Accessory salivary gland was larger than principal salivary gland in Toxoptera citricidus. 4. In 4 species, e. g. Chaitophorus chinensis, Myzus persicae, Aphis craccivora, Toxoptem citricidus, the stylets were usually inserted in plant tissues intercellularly and reached phloem, however, in Lachnus tropicalis only intracellularly and in Eriosoma clemalis more frequently intracellularly. 5. The stylets tracks of Eriosoma clemalis, Lachnus tropicalis and Myzus persicae were clearly visible but not in Toxoptera citricidus, Chaitophorus chinensis and Aphis craccivora. The tracks were stained with yellowish brown or red brown. 6. Saliva was seceted between the cell walls in most species and some substances in saliva seem to cause loosend cell walls. 7. The penetration of the stylets might cause physiological disturbance to host plants and could make the host plants susceptible to the plant diseases.

• Journal of the Korean Society of School Health
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• v.24 no.1
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• pp.61-70
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• 2011

Purpose: To identify factors associated with children's discriminatory attitudes towards fully recovered children who contracted the 2009 Influenza A (H1N1), in order to provide fundamental information to improve health education for children. Methods: Cross-sectional data were collected from the entire 6th grade classes (N=2,323) of 11 elementary schools randomly selected from 11 school districts in the Seoul Metropolitan Area of South Korea. Questionnaires were used to assess participants' knowledge of and attitudes towards the Influenza A (H1N1) virus. Results: Multiple regression analyses were used to investigate the factors associated with children's discriminatory attitudes toward fully recovered children who had contracted the 2009 Influenza A (H1N1). Multiple regression analysis revealed that perceived risk of contracting and knowledge of 2009 influenza A (H1N1) were significant factors in predicting a child's attitude toward fully recovered Influenza A (H1N1) patients, after controlling for socioeconomic variables. Conclusion: The findings suggests that perceived risk and knowledge play important roles in formulating children's appropriate attitudes towards Novel influenza A (H1N1) patients who are fully recovered from the disease. To promote and maximize children's attitudes in this area, health education needs to be directed at children to reduce excessive concern about contracting the virus and to improve their overall health knowledge.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.1
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• pp.19-26
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• 2019

Simulation using the virtual reality has been applied in various fields such as exercise, education, disaster simulation training, but there is a little research on disease caused by virus transmission. In this study, we conducted simulation studies and analysis of avian influenza disaster response training. The annual avian influenza virus is recurring every year in Korea, but there are still few solutions and preventive measures for the preventing the avian influenza. The avian influenza can cause a great deal of societal harm and enormous economic damage. Prophylaxis is important because livestock epidemics, such as avian influenza and foot-and-mouth disease, have a large impact on farm households. Therefore, we proposed and analyzed contents that can be avoided through simulation of avian influenza disaster response presented in this study.

• Journal of the Korean Statistical Society
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• v.35 no.4
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• pp.397-407
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• 2006

A new stochastic process is introduced for describing a mechanism of viruses. The process generalizes the $Bartoszy\'{n}ski's$ process ($Bartoszy\'{n}ski$, 1975a, 1975b, 1976) by allowing the stochastic perturbation between consecutive jumps to take into account the persistent infection (the infection without breaking infected cells). It is shown that the new process can be obtained by a weak limit of a sequence of Markov branching processes. Along with the construction of the new process, we study how the stochastic perturbation influences the risk of a symptom in an infected host. For this purpose, the quantal response model and the threshold model are investigated and compared through their induced survival functions.

• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.815-822
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• 2001

The aim of this study is to estimate the seroconversion date of the human immunodeficiency virus(HIV) infection for the HIV infected patients in Korea. Data are collected from two cohorts. The first cohort is a group of "seroprevalent" patients who were seropositive and AIDS-free at entry. The other is a group of "seroincident" patients who were initially seronegative but later converted to HIV antibody-positive. The seroconversion dates of the seroincident cohort are available while those of the seroprevalent cohort are not. Estimation of seroconversion date is important because it can be used to calculate the incubation period of AIDS which is defined as the elapsed time between the HIV infection and the development of AIDS. In this paper, a Weibull regression model Is fitted for the seroincident cohort using information about the elapsed time since seroconversion and the CD4$^{+}$ cell count.The seroconversion dates for the seroprevalent cohort are imputed on the basis of the marker of maturity of HIV infection percent of CD4$^{+}$cell count.unt.

• Korean Journal of Veterinary Research
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• v.6 no.1
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• pp.31-36
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• 1966

The free amino acid contents in several tissues of swine were analyzed qualitatively by means of two dimentional paper chromatography. The tissues used were liver, kidney and spleen that were obtained from normal, immunized and hog cholera infected swines. The results obtained are as follows: 1. Liver: 20 amino acids were detected in normal, 17 in immunized and 15 in infected swines. 2. Kidney: 16 amino acids were detected in normal, 13 in immunized and infected swines. 3. Spleen: 15 amino acids were detected in normal in immunized and 13 in infected swines. 4. Glutamic acid, leucine, serine and threonine were present in high concentration in all of the cases examined. 5. The free amino acids were appeard to be decreased in the infected tissues with hog cholera virus.