• Korean Journal Plant Pathology
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• v.12 no.1
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• pp.47-57
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• 1996

병원성 Fusarium에 의한 아스파라거스 감염은 비병원성 Fusarium을 5일과 7일 전에 접종하였을 때 방제효과가 있었다. 비병원성 F. oxysporum은 F. moniliforme에 대하여 방제효과가 있었고, F. solani는 F. oxysproum에 대하여 방제효과가 있음이 밝혀졌다. 실험에 사용된 Fusarium 균들은 모두 주근과 측근의 말단 부위, 상처부위, 그리고 표피의 세포벽 사이를 통하여 감염하였다. 경우에 따라 감염하는 동안 appressorium과 유사한 구조를 형성하기도 하였고, 직접 감염하는 경우도 있었다. 병원성 그리고 비병원성 Fusarium 균 모두 공통적으로 생장점 부위를 통하여 감염하였다. 병원성이 강한 Fusarium 균의 경우 비병원성 균들보다 감염의 속도가 빨랐고 더욱 생장이 왕성하였다. F. solani는 생장속도나 기주 조직 침입속도가 매우 느렸다. 기주 감염의 결과 처음에는 cortical rot을 유발시켰고 나중에는 tracheary elements를 감염하고 결국은 조직의 괴사를 유발하는 것이 관찰되었다. 비병원성 F. oxysporum은 표피조직에 두터운 균사층을 형성하였고, 이는 병원성 Fusarium 균에 대한 방제효과를 나타내는 원인을 제공한 것으로 여겨진다. F. solani는 측근의 생성을 촉진시켜 표면적을 증대시킨 것으로 여겨진다. 결론적으로 AVFO와 F. solani를 이용하여 아스파라거스에 발생하는 병원성 Fusarium균의 침입을 저지할 수 있는 생물적 방제가 가능함이 밝혀졌다.

• Journal of Life Science
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• v.4 no.2
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• pp.64-69
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• 1994

동물 실험과 환자에서 M. fermentans 감염은 염증반응을 동반하거나 하지 않으며, 병변이 나타나지 않은 것에서부터 전격성 감염에 이르기까지 다양하다. 이와 같은 현상이 나타나는 것은 두 가지 기전 중에 어느 하나 일 것으로 Lo등과 Montagnier 등은 추정하고 있다. Mycoplasma 감염이 숙주의 면역기구의 주된 성분에 손상을 주거나, 이 병원체가 감염된 숙주의 면역감시기구를 피할 수 있는 특수한 생물학적 특성을 가지는 것이다. AIDS관련 mycoplasma 감염의 가능한 역할은 첫째 mycoplasma는 AIDS환자나 면역 기능부전인 사람에서 단순한 기회적감염이거나, 둘째 M. fermentans나 M. penetrans와 같은 mycoplasma의 감염은 HIV-1과 같은 virus의 병원성을 증강시켜주거나, 셋째 mycoplasma가 숙주의 면역성을 저하시키는 병원성일 가능성을 가지고 있다.

• Journal of fish pathology
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• v.12 no.2
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• pp.107-113
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• 1999

The pathogenicity of the fish nodavirus causing viral nervous necrosis (VNN) of sevenband grouper, Epinephelus septemfasciatus was examined in sevenband grouper and other marine fish by intramuscular injection. Sevenband groupers of 27~104 g in body weight were highly susceptible to the fish nodavirus, but yellowtail (537 g in body weight), red seabream (207 g), rock bream (43 g), flounder (41 g), tiger puffer (27 g) and rockfish (94 g) of the sizes used to this experiment were not. The pathogenicity of the viral agent to the sevenband grouper was high without regard to fish sizes at rearing water temperature over $20^{\circ}C$, but not at $15^{\circ}C$. Therefore, susceptibility of sevenband grouper to the viral agent causing VNN was thought to be water temperature-dependent rather than fish size (age-dependent). Compared to the infectivity of the viral agent to sevenband grouper with artificial infection methods, fish were successfully affected by intramuscular, intraperitoneal, oral, dipping and cohabitation administrations although there were slight differences in mortalities among infection methods. And survival sevenband grouper after infection with the fish nodavirus was resistant to the reinfection for a long time.

• KOREAN POULTRY JOURNAL
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• v.4 no.9 s.35
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• pp.33-36
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• 1972

1. 마렉 감염계는 환경을 오염한다. 3. 감염원인 병독은 오랫동안 생존한다. 3. 따라서 감염성계는 오염환경에서 직접, 간접 간염한다. 이 병의 감염경로는 아직 확정되어 있지 않으나 주로 기도감염일 것으로 인정되고 있다. 4. 본 병의 감염은 병독 보유계의 우모근이 각화하여 탈각하는 상피세포중에 함유되는 병원성 병독이 야기 한다는 것은 확정적이다. 또 이 방법이 마렉병 감염을 반복하는 유일의 원인으로 생각하고 있다. 5. 본 병의 개란전파에 대해서는 거의 없는 것으로 알고 있으나 Sevoian은 전달의 가능성이 있다고 한다. 6. 임파종증일때와 마찬가지로 저항성품종과 감염성품종을 선택 도태를 함으로써 만들어져 있다. 이들은 마렉병에 대하여 저항성품종은 5$\%$의 발병성을 나타내고 감염성 품종은 90$\%$의 발병성을 나타내고 있다.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.189-202
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• 2008

The aim of this study was conducted to investigate the level of awareness and performance of the physical therapists on nosocomial infection and evaluate potential factors as associated with awareness and performance in order to provide fundamental data for the development of program and policy on the prevention of it. The data were collected from 405 physical therapists. The research instrument was self-administered standardized questionnaire including general characteristics, education status, necessity of the education on nosocomial infection, and awareness and performance for prevention of nosocomial infection. Responses were determined as 5-Likert scales and data were summarized as percentage, mean and standard deviation. Data were analysed using independent t-test, ANOVA and Pearson's correlation coefficient(${\alpha}=0.05$). The results of this study show that most physical therapists have not received education on nosocomial infection. For this reason, they have a low level of the awareness and performance on nosocomial infection, but they strongly recognize the necessity of the program and education for the prevention of nosocomial infection. Thus, these program and education are needed in each college as an academic curriculum, as well as in hospitals.

• Parasites, Hosts and Diseases
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• v.21 no.2
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• pp.234-240
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• 1983

The pathogenicity of free-living amoeba, Waegleria fcwleri, is influenced according to the strain, cultural condition and host (Culbertson et at., 1968; Carter, 1970; Wong et at., 1975), Phillips (1973) demonstrated that Entamoeba histolytica became avirulent after more than 2 year maintenance in axonic culture in vitro. This study was carried out to compare the difference in pathogenicity between two strains of N. fowleri, one of a prolonged maintenance in arsenic medium and the other one obtained by serial brain passage in mice. The 0 strain was that N. fowleri had cultivated axenically more than 7 years in CGVS medium. The 2-1 strain was obtained from the brain of mouse inoculated intranasally with a strain, which was from the mouse brain infected with 0 strain, and cultured for 15 weeks until the beginning of this experiment. White male mice weighing 18-22 g were used. Mice were anesthetized by an intraperitoneal injection of about 1 mg secobarbital, and inoculated intranasally with $10{\times}$10^4 live N. fowleri trophoBoites in a $5{\;}{\mu}l$ cell suspension. Sluggish behaviour, nervousness, rotation and leg paralysis were developed earlier and more frequently in the 2-1 experimental group than the control 0 group. Pathological changes such as inflammatory and necrotic lesion were observed in the olfactory and anterior portion of brain, and these changes were more extensive in the 2-1 group. The edematous and inflammatory changes in lung were demonstrated in mice died after 13th day post-inoculation. The experimental mice of 2-1 group began to die suddenly from 7th day post-inoculation, and the survival time in 2-1 group mice was shorter than 0 group mice. The typical primary amoebic meningoencephalitis was developed in the mice inoculated intranasally with N. fowleri. The prolonged maintenance of N. fowleri amoebae in axonic CGVS medium was observed to have lost their original pathogenicity for mice, but their pathogenicity was restored by serial brain passage in mice.

• Journal of fish pathology
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• v.14 no.1
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• pp.16-20
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• 2001

The pathogenicity of the extracted WSBV from the hepatopancreas, the lymphoid organ, the stomach and the heart of infected shrimps was examined after artificial infection in shrimps(Penaeus chinensis). In terms of the infection route, the strength of the pathogenicity of WSBV was in the order of intramuscular, oral and dipping method. The influence of rearing water temperature on the pathogenicity of WSBV was the strongest in the order of $30^{\circ}C$, $25^{\circ}C$, $20^{\circ}C$, and $15^{\circ}C$. The isolated WSBV from the diseased shrimps showed very high pathogenicity regardless of their sizes, even though there was difference in time to reach 100% mortality. Degenerated cells characterized by hypertrophied nuclei were found in various tissues such as the lymphoid organ, the hematopoietic tissue and the epidermis in the stomach.

• Parasites, Hosts and Diseases
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• v.31 no.3
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• pp.239-248
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• 1993

The purpose of this observation was to investigate the natural killer cell activities in mice Infected with pathogenic free-living amoeba, Naegleria fowleri and Acanthomoeba culbertsoni according to the infection doses, and infected with non-pathogenic free-living amoeba, Naegleria fowleri. The natural killer cell activity was examined by means of target binding capacity, active NK cell and maximum recycling capacity of the mice after inoculating free-living amoebae with low and high doses. The mice infected with 1 103, 1 105 A. culbertsoni trophozoites showed mortality rates of 6.9% and 65.5%, respectively. The mice infected with 1 104, 1 105 N.fowleri trophozoites showed mortality rates of 5.9% and 72.2%, respectively. The NK cell activities in all experimental groups increased significantly on day 1 after infection as compared with control group, and then remarkably declined thereafter, there was no difference of the cytotoxic activity of the NK cells In mice among inoculation doses of pathogenic free-living amoebae. The target binding capacities of NK cells and percentages of activated NK cells in mice Infected with pathogenic free-living amoebae were slgrlificantly Increased a day after Infection, as compared Uth control group. There was no difference of the maximal recycling capacities of NK cells in all experimental groups as compared Uth control group. There was significant difference in the cytotoxic activity and single cell cytotoxlcity of NK cells between the experimental groups infected with pathogenic free-living amoebae and that infected with non-pathogenic free-living amoebae.

• Korean journal of applied entomology
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• v.39 no.3
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• pp.193-197
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• 2000

Wolbachia, vertically transmitted bacterial endosymbionts, is known to induce cytoplasmic incompatibility (CI), parthenogenesis, or feminization in some insect species. The Wolbachia found to exist symbiotically as a non-virulent form in Drosophila melanogaster, however popcorn is a lethal strain of Wolbachia, which causes tissue degeneration and early death of its adult host. Popcorn-infected flies showed the delayed duration of an egg and larvae, and their pupal period and life span reduced. The oviposition and egg-hatching rate of popcorn-infected flies were decreased 15% and 80%, respectiv~ly, compared to those of the normal Wolbachia-infected flies. The pupation and emergence rates of popcorn-infected flies were 67% and 65%, respectively. When popcorn-infected flies were crossed with Wolba-chia-infected flies, and vice versa, both crosses resulted in a significant reduction in egg production, egg¬hatching, pupation, and emergence rate, and their progeny revealed the popcorn syndrome. When popcorn-infected male flies were crossed with uninfected females, popcorn was not detected in their progeny. Popcorn also maternally transmitted in flies, but it did not induce CI and affected on its host life cycle as a virulence.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.461-470
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• 2015

This study was to identify the level of perception and practice of hospital infection control among nurses at geriatric hospitals for the convergent approach. Data were collected from October 29 to November 3, 2012, using hospital Infection control questionnaire. Data analysis was performed using a t-test, ANOVA and Correlation. The mean values of hospital infection control practice were lower than that of perception, the differences were statistically significant. There were statistically significant differences in the perception on age, education, existence of guidelines for infection control, and in the practice according to the existence of guidelines. There was a statistically significant positive correlation between perceptions of hospital infection control and practice. Therefore, it is necessary to provide continual opportunities for systematic, professional, and practical education, as well as to develop relevant programs aimed at improving the capacity of hospital infection control.