• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.118-125
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• 2012

Heat shock proteins (Hsps) play a key role in the cellular defense response to diverse environmental stresses. Here, the role of Hsp genes in the acquisition of thermotolerance in the cyanobacterium Microcystis aeruginosa NIES-298 was investigated. Twelve Hsp-related genes were examined to observe their modulated expression patterns at different temperatures (10, 15, 25, and $35^{\circ}C$) over different exposure periods. HspA and HtpG transcripts showed an up-regulation of expression at low temperatures (10 and $15^{\circ}C$) and high temperature ($35^{\circ}C$), compared with the control ($25^{\circ}C$). To examine their effects upon thermotolerance, we purified recombinant HspA and HtpG proteins. During a thermotolerance study at $54^{\circ}C$, the HspA-transformed bacteria showed increased thermotolerance compared with the control. HtpG also played a role in the defense response to acute heat stress within 30 min. These findings provide a better understanding of cellular protection mechanisms against heat stress in cyanobacteria.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.2
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• pp.52-65
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• 1999

This study was performed to evaluate the hand-arm vibration of the steel processing factory workers. Measurement, evaluation and as sessment were based on the International Standard(ISO 5349). The frequency weighted accelerations of the various hand-held tools and total exposure time were measured to assess the periods for the white finger symptom to occur. As a result, it was found that the air angle grinder and the air baby grinder are more harmful than other hand-held tools. It was also found that using various vibratory tools together is more harmful than using a single tool.

• Reproductive and Developmental Biology
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• v.28 no.4
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• pp.235-240
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• 2004

In vitro maturation of denuded porcine immature oocytes can be enhanced by co-incubation with spermatozoa even before fertilization. This study was to determine whether the addition of spermatozoa into the culture medium could influence the nuclear maturation of porcine cumulus-enclosed germinal vesicle (GV) oocytes. Cumulus-oocyte complexes (COCs) were collected from follicles of 3- to 5-mm diameter. Porcine COCs were cultured in tissue culture medium containing spermatozoa. After 48 h culture, oocytes were examined for evidence of GV breakdown, metaphase I, anaphase-telophase I, and metaphase II. The proportion of oocytes reaching at metaphase II was significantly (P < 0.05) increased in the oocytes cultured in media containing spermatozoa compared to those in media without spermatozoa (52.3% vs 12.5%). No difference in the percentage of metaphase II was observed among the different periods of spermatozoa exposure and among the spermatozoa from different species. The proportion of oocytes reaching metaphase II was significantly different between high and low concentrations of spermatozoa. The present study suggests that manunalian spermatozoa contain a substance(s) that improves nuclear in vitro maturation of porcine cumulus-enclosed GV oocytes. Enhancing effect of spermatozoa for in vitro maturation of oocytes is a highly dose-dependent.

• Journal of Life Science
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• v.6 no.2
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• pp.111-119
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• 1996

The production of interleukin-1(IL-1)and nitric oxide(NO) by cultured fibroblast cells of human nasal turbinate was revealed by biological assay respectively. The cells were incubated for various periods of time in the presence of staphyloccocal toxic shock syndrome toxin-1(TSST-1) and house dust mite(Dermatophagoides farinae, HDM), and the culture supernatants were harvested. There was a little difference in the activities of IL-1beta and the amount of NO produced by the cells when stimulated with 0.002-0.1$\mu$g/ml of TSSTO-1 and 0.02-1$\mu$g/ml of HDM. The shapes of the time course curves for the production of IL-1beta and NO by the cells were different. Groups stimulated with TSST-1 or HDM produced more IL-beta in 2 h than no exposure group(Control). A certain mixed group(TSST-1, 10ng+mite, 100 ng) continued to produce IL-1beta highly throughout the entire incubation period. The cells stimulated with TSST-1 or HDM produced more NO in 2 h and 6 h than that produced in the end of incubation(48 h). Also, the mixed groups were generally similar. There results suggest that induction of IL-1beta by a certain mixed condition(TSST-1+mite) in fibroblast cell in vivo may play a role in inflammation.

• Korean Journal of Food Science and Technology
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• v.26 no.5
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• pp.585-589
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• 1994

The effects of T-2 toxin on mitogen-induced blastogenesis of chick splenic cells were investigated. The [$^3H$] thymidine incorporation in splenic cells stimulated by lipopolysaccharide and concanavalin A were equally inhibited as the concentration of T-2 toxin was increased. The effective dose of T-2 toxin causing a 50% reduction of [$^3H$] thymidine incorporation was inbetween 1.0 and 5.0 ng/ml for both mitogens. Mitogen-induced blastogenesis in chick splenic cells showed differences among experimental groups with different exposure time of T-2 toxin, exhibiting the most inhibition in the experimental group exposed to T-2 toxin at both embryonic and chick periods.

• The Korean Journal of Pain
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• v.8 no.2
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• pp.347-349
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• 1995

A 43 year old man who suffered from right facial palsy was treated successfully with the application of both magnetic resonance diagnostic analyser(MRA) and drug therapy. Treatment of facial palsy is generally composed of stellate ganglion block(SGB), drug therapy and operative intervention. Short periods of exposure to appropriate magnetic resonance can beneficially modulate the balance of autonomic nervous system that are responsible for sympathetic overflow. It was concluded that recovery of facial palsy by application of both MRA and drug therapy was effective in patient who refused SGB.

• The Korean Journal of Pain
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• v.6 no.2
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• pp.280-283
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• 1993

Idiopathic hyperhidrosis is a physically and emotionally distressing symptom, which lacks a precise definition. Although operative and nonoperative methods have been shown to be effective in the treatment of idiopathic hyperhidrosis, limitations, cautions and complications are inherent in their extended use. The purpose of this report is to describe the theraputetic effects of magnetic resonance for managing idiopathic hyperhidrosis. A 28 years old woman had been suffering from profuse sweating on both planter and palmar sides for 15 years. We successfully treated this symptom with the 6 magnetic resonance treatments without any complications. Now she lives well in a condition of normal sweating after the applications. It suggest that short daily periods of exposure to appropriate magnetic resonance can beneficially modulate the balance of autonomic nervous system that are responsible for sympathetic overflow, and that there is an effective window of induced electrical magnetism in which sympathetic function can be controlled in the absence of side effects.

• International Journal of Concrete Structures and Materials
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• v.3 no.1
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• pp.25-32
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• 2009

A non-destructive testing (NDT) method for evaluating physical properties of concrete including the compressive strength is highly desirable. This paper presents such an NDT method based on measurement of electromagnetic (EM) properties of the material. Experiments are carried out on cement mortar with different water/cement (W/C) ratios. Their EM properties including the conductivity and the dielectric constant are measured at different exposure conditions and curing periods over a wide frequency range of the EM wave. The compressive strength of these specimens is also tested. It is found that both the conductivity and the dielectric constant increase as the W/C ratio decreases and the curing period increases, which lead strength development in the specimens. A linear correlation is observed between the averaged EM properties over the 5 to 20 GHz frequency range and the measured compressive strength, demonstrating the effectiveness of the EM property-based NDT method in evaluating strength of OPC mortar.

• Journal of the Korean Geosynthetics Society
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• v.3 no.1
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• pp.37-42
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• 2004

In the reinforced retaining wall system, non-woven geotextiles are placed at the face of reinforced earth until the facing blocks are built up. And when this system is used as temporary structure, geotextiles facings are exposed to sunlight during service lifetime. During these periods, degradation of nonwoven geotextiles are occurred by UV light. So the UV-resistance of nonwoven geotextiles must be assessed correctly, in considering of the site conditions. In this study, laboratory test and the field test have been performed to evaluate the UV resistance of non-woven geotextiles used in KOESWall system and the results are expressed in terms of tensile characteristics & SEM photographs.

• Parasites, Hosts and Diseases
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• v.39 no.3
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• pp.223-226
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• 2001

In South Korea, the north border area has been under vivax malaria epidemic since 1993. However, Jeollabuk-do, which is about 300 kms from the border, has not experienced the same epidemic. 1 investigated a total of 58 notified cases of malaria in Jeollabuk-do in the year 2000. All of the cases had an exposure history in the epidemic area. Among them were 49 ex-soldiers, 3 soldiers who served near the border area and 6 civilians who traveled there. The causal agent of all cases was Plasmodium vivax. Except the civilians, the soldiers and ex-soldiers were aged in their twenty's. In the present study, the incubation period was from 6 to 520 days with a median of 157 days, and the latent onset type (92%) was more prevalent than the early onset type. illness onset of most cases (86%) peaked during the summer season (June to September) despite of variable incubation periods. The time lag for diagnosis ranged from 2 to 42 days with a median of 11 days. Jeollabuk-do has not been an area of epidemic untill now, but incidences have been increasing annually since 1996. In Jeollabuk-do, early diagnosis and treatment can be a feasible disease control measure to prevent spreading from the epidemic area.