• Korean Journal of Veterinary Service
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• v.27 no.2
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• pp.133-137
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• 2004

This study was attempted to survey on the prevalence of canine heartworm(Dirofilaria immitis) infections among 206 dogs (male 92, female 114) in Daejeon area from March to December 2003. Blood samples taken from dogs were examined for the presence of D immitis microfilaria by the modified Knott's test and an antigen test( $AGEN^{TM}$ canine heartworm). The result obtained from this experiment were summarized as follows; 1. Eighteen(8.7%) of the 206 examined dogs were microfilaria positive, while twenty five dogs(12.1%) were antigen test positive. 2. The infection rates of heartworm in dogs at the age of <2, 2∼4 and $\geq$5 were 3.8%, 18% and 25%, respectively. 3. The infection rates of heartworm in dogs by housing of indoor and outdoor were 3.3% and 36.4%, respectively. 4. The regional infection rates were Dong-gu(13/29, 44.8%), Seo-gu(7/92, 7.6%), Yuseong-gu(2/33, 6.1%), Jung-gu(1/17, 5.9%) and Daedeok-gu(2/35, 5.7%). 5. The seasonal infection rates were summer(June∼August, 16.7%), autumn (September∼October, 14%), spring(March∼May, 9.4%) and winter(November∼December. 7.7%).7.7%).

• Journal of Microbiology and Biotechnology
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• v.22 no.5
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• pp.585-591
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• 2012

The antagonistic effect of Trichoderma harzianum on a range of seed-borne fungal pathogens of wheat (viz. Fusarium graminearum, Bipolaris sorokiniana, Aspergillus spp., and Penicillium spp.) was assessed. The potential of T. harzianum as a biocontrol agent was tested in vitro and under field conditions. Coculture of the pathogens and Trichoderma under laboratory conditions clearly showed dominance of T. harzianum. Under natural conditions, biocontrol effects were also obtained against the test fungi. One month after sowing, field emergence (plant stand) was increased by 15.93% over that obtained with the control treatment, and seedling infection was reduced significantly. Leaf blight severity was decreased from 22 to 11 at the heading stage, 35 to 31 at the flowering stage, and 86 to 74 at the grain filling stage. At harvest, the number of tillers per plant was increased by 50%, the yield was increased by 31.58%, and the 1,000-seed weight was increased by 21%.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.1007-1012
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• 1996

The purpose of the survey was to understand the field situation on the occurrence of enteric diseases in poultry farms in Korea. During the period from January of 1991 to December, 1992, 279(35.8%) out of 779 farms surveyed experienced the cases of enteritis in their chickens. The farms with diarrheal problems consisted of 157(45.1%) of 348 broiler flock, 28(32.6%) of 86 breeder flock, and 94(27.2%) of 345 layer flock. The main diseases causing enteritis were frequently appeared as infectious bursal disease(27.3%), colibacillosis(22.6%), and coccidiosis(8.6%). Necrotic enteritis(NE) in chicken occurred in 21 farms(2.7%) among 779 farms examined. The outbreaks of NE were divided 4.7% in breeders, 4.0% in broilers, and 0.9% in layers, respectively. NE occurred mainly in the age(71.4%) of 20~30 days and the mortality was varying from 1.4% to 10.0% for broilers, 3.0% for layers and 0.8% for breeders. Seasonal prevalence of NE showed the highest as 52.4% in summer and followed by 33.3% in autumn, 9.5% in spring and 4.5% in winter.

• The Plant Pathology Journal
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• v.40 no.1
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• pp.83-97
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• 2024

Fusarium graminearum, the causal agent of Fusarium head blight (FHB) in cereal crops, employs the production of sexual fruiting bodies (perithecia) on plant debris as a strategy for overwintering and dissemination. In an artificial condition (e.g., carrot agar medium), the F. graminearum Z3643 strain was capable of producing perithecia predominantly in the central region of the fungal culture where aerial hyphae naturally collapsed. To unravel the intricate relationship between natural aerial hyphae collapse and sexual development in this fungus, we focused on 699 genes differentially expressed during aerial hyphae collapse, with 26 selected for further analysis. Targeted gene deletion and quantitative real-time PCR analyses elucidated the functions of specific genes during natural aerial hyphae collapse and perithecium formation. Furthermore, comparative gene expression analyses between natural collapse and artificial removal conditions reveal distinct temporal profiles, with the latter inducing a more rapid and pronounced response, particularly in MAT gene expression. Notably, FGSG_09210 and FGSG_09896 play crucial roles in sexual development and aerial hyphae growth, respectively. Taken together, it is plausible that if aerial hyphae collapse occurs on plant debris, it may serve as a physical cue for inducing perithecium formation in crop fields, representing a survival strategy for F. graminearum during winter. Insights into the molecular mechanisms underlying aerial hyphae collapse provides offer potential strategies for disease control against FHB caused by F. graminearum.

• Clinical and Experimental Pediatrics
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• v.45 no.7
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• pp.896-901
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• 2002

Purpose : The aim of this study was to determine the epidemiology of Kawasaki disease in the Kyung Nam area and to evaluate whether the results of this epidemiological study could support infectious etiology. Methods : We sent a questionnaire to three training hospitals in the Kyung Nam area and retrospectively reviewed their medical records of Kawasaki disease from Jun. 1995 to Dec. 1999. Results : The total number of patients was 717 cases, with little differences of annual prevalence during the five years. In all cases, the monthly prevalence of Kawasaki disease was high in Apr. and Jul. At the eastern of Kyung Nam, the monthly prevalence was high in Apr. and Jul. in 1995 and 1996, Jul. in 1997, Apr. in 1998 and Apr. and Jul. in 1999. In the central area of Kyung Nam, the monthly prevalence was high in Apr. in 1995 and 1996, Apr. and Jul. in 1997 and Jul. in 1998 and 1999. In the western Kyung Nam, the monthly prevalence was high in Nov. in 1995, Aug. in 1996, Oct. in 1997, Dec. in 1998 and Nov. in 1999. Conclusion : In the eastern and central areas of Kyung Nam, the monthly prevalence of Kawasaki disease was similarly high in Apr. and Jul. However, in the western district, the prevalence was high in late fall and winter. We could not prove the hypothesis that Kawasaki disease occurred with the spread of single infectious agent, but the a nnually similar prevalence in eastern and central Kyung Nam supported the infection theory for the etiology of the disease.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.361-370
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• 1982

The effects of climatic factors on organisms lire variable and complex, and it, however, can be interpreted in terms of those on the distribution and those on the population densities. The distribution of an organism may largely be determined by the temperatures, except some temporal organisms which are depended on the air mass movements. Population density of an organism is determined by various climatic factors, such as previous winter temperature, temperature of growing season and rainfall. The start of growing season of the rice plants has been shifted to earlier since last decade in Korea. This may mean that the overall climatic condition during the growing season might be considerably different from those in past years, and such a difference in climatic conditions might have close relation with the recent status of the diseases and insect pests through direct effects on the physiology and population dynamics of the organisms, as well as through on the biotic associations of the pest organisms. The white back planthopper and brown planthopper have become the key insect pests in Korea in recent years. They are migratory and have high reproductive pontentials and more generations than average residential insects. The synchronization of the migrants and physiological condition of the rice plants seems to be the important factors in relation to the recent outbreaks of these insects; the high reproductive rate can be obtained with the growth stage of rice being 30-50 days after transplanting. The modication of the microclimate associated with high plant density and some other introduced new cultural techniques also have some relation with the outbreak. The key diseases of the rice are the blast disease, sheath blight and the bacterial leaf blight. For the rice blast, the seedling blast and leaf blast during the early growing season and the neck blast, have become more serious, the former may be related to hotbed nursery and the later may be related to the high humidity in early August, and synchronization of the heading time which has been shifted to early part from middle or late part of August. In general, for the rice diseases, the development of the new races have been the most serious which are largely resulted from the introduction of the new varieties, but it also seems to be related with the prolonged periods of the favorable condition associated with the shifted growing seasons. In general, the diseases and insect pest problems have become much more variable and complex, and control measures should be based on the thorough knowledge of the ecology of the pest organisms, that is, effects of various environmental factors on the disease cycle; spore release, spore deposition, infection, colonization and sporulation of the disease organisms, and those on the development, reproductive potentials, dispersal, age specific responses of the insects. The well organized real-time pest management systems, such as alfalfa weevil management system developed at the Purdue University in U.S., is the prime importance for the implementation of the pest management principles.

• Research in Plant Disease
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• v.23 no.3
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• pp.283-287
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• 2017

The twig blight of mulberry caused by Fusarium lateritium occurs mainly in Buan area, which is the main area of mulberry. The initial symptom on twigs showed dark edge blight and dark orange tiny particles on the spot, and it was withered and died. In the case of mulberry twig blight, the difference in the degree of occurrence between the years is intense, and an average of 2.7% occurred in Buan in 2013, but in 2014, it was difficult to search for the generated fields. In order to find the cause of the difference in the incidence of mulberry twig blight, we investigated and analyzed the weather conditions during cultivation and as a result, the occurrence of the disease increased under the condition that the temperature of the spring was lower and the number of days passing below the winter freezing point increased. In addition, it was analyzed that the occurrence of the next year increases when the rainfall is high and the number of sunshine is low after removing the harvested branches. Therefore, in the event that weather conditions causing twig blight diseases have elapsed, it is necessary to prevent the disease by spraying the registered applied fungicide prophylactically.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.160-170
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• 2011

Commercial formulation of fungicides was studied in vitro for sensitivity against Typhula species causal agents of Typhula blight. Efficacies of fungicides application, spray volume, nozzle types and fungicides applied time (early fall and late fall) were evaluated for their influence on the chemical control of Typhula blight of turfgrass during the winter season in Wisconsin. All fungicides effectively reduced the mycelial growth of eight isolates of Typhula spp. in vitro on potato dextrose agar (PDA) media. For inhibitory effects on mycelial growth of eight isolates, propiconazole was the most effective at $1.0{\mu}g$ active ingredient (a.i) / ml of PDA. Typhula incarnata two isolates were significantly more sensitive to all fungicides of PDA than six isolates of three varieties of T. ishikariensis. For 2 years in field experiment, unsprayed control has significantly more disease severity than seven fungicides were applied to field plots at two locations. Propiconazole was the most effective for controlling Typhula blight, at two locations in both years. The level of disease control was not dependent on fungicides spray volume or nozzle types at two locations. The disease damage treated with triadimefon applied time (early fall and late fall) was not significantly different at two location for two years.

• Pediatric Infection and Vaccine
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• v.17 no.1
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• pp.49-55
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• 2010

Purpose : The Purposes of this study are to identify the circulating etiologic viruses of acute lower respiratory tract infection in children and to understand the relation with clinical diagnosis. Methods : We obtained a total of 418 nasopharyngeal aspirates from children admitted for their acute lower respiratory tract infections at three tertiary hospitals in Seoul from September 2008 to March 2009. We performed multiplex RT-PCR to identify 14 etiologic viruses and analyzed their emerging patterns and clinical features. Results : Average age of patients was 16.4 months old and the ratio of male to female was 1.36. Viruses were detected in 56.2% of a total of 418 samples. Respiratory syncytial virus (35%) was the most frequently detected and followed by human rhinovirus (22%), human bocavirus, adenovirus, human metapneumovirus, parainfluenza virus, influenza virus and human coronavirus. Co-infection reached 21.9 % of positive patients. Conclusion : When we manage the patients with acute lower respiratory infectious diseases, we should remind the role of various viral pathogens, which might be circulating by seasons and by local areas.

• Journal of Acupuncture Research
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• v.20 no.1
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• pp.85-96
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• 2003

Objectives : We were studied the retaining needle to offer basic materials for the study of it. methods: To study the retaining needle, we were reviewed the ancient, the present text and the thesis. Results: 1. There are many ways form general acupuncture technique to needle-embedding therapy by the spending time of the retaining needle. 2. The method retaining needle is divided into Active method of the retaining needle(動留針法) and Passive methoid of the retaining needle(靜留針法) by the existence of Qi-promoting. 3. In case of Deficiency Syndrome, protracted discase, dolorific disorder, convulsive disorder, and Cold Syndrome, the spending time of the retaining needle takes longer, in case of Heat Syndrome and exterior Syndrome, the spending time of the retaining needle takes shorter. 4. In case of acute disease and attack of chronic disease, we can use Active methoid of the retaining needle(動留鍼法) with retaining needle for a long time, in case of chronic disease, we can use Passive methoid of the retaining needle(靜留針法). 5. In case of Young people, a man in the prime of life, and a people who can stand the stimulation of needle, we can make the spending time of the retaining needle be longer and use Active methoid of the retaining needle(動留針法), but in case of a baby and a weak people, we had better shorten the spending time of the retaining needle or not do it. 6. The spending time of the retaining needle must be shorter in spring and summer, must be longer in fall and winter. 7. The spending time of the retaining needle is various by acupuncture point. 8. When the spending time of the retaining needle is too longer, we can injure Vital-qi of a patient, otherwise in opposite situation, Pathogenic is stagnated so pathogenic stage is repeated.