• Parasites, Hosts and Diseases
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• v.44 no.3
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• pp.265-268
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• 2006

The present authors investigated intestinal parasitic infections among North Korean residents and refugees in China in 2003. The Kato-Katz method was applied to 236 residents and soldiers in a town on the North Korea-China border and to 46 people at a refugee camp in China. Only eggs of Ascaris and Trichuris were detected, with egg positive rates of 41.1 % and 37.6%, respectively. The total egg positive rate was 55.0% and most of those who were egg positive were only lightly infected. Women of 61.2% and men of 53.1 % were egg positive. The refugees from rural areas showed higher egg positive rates than those from urban areas. The present investigation confirmed high prevalence of soil-transmitted intestinal helminths in rural borderline areas of North Korea.

• Parasites, Hosts and Diseases
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• v.47 no.4
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• pp.425-426
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• 2009

The present study investigated the infection status of Paragonimus westermani metacercariae in freshwater crabs (n = 363) and crayfish (n = 31) from October 2007 to October 2008 using the crush method. All of the freshwater crabs, Eriocheir japonicus, were negative for P. westermani metacercariae while 10 (32.3%) of the 31 examined crayfish were positive. The 10 positive crayfish were caught in Haenam, Jeollanam-do, and there were 8-59 (mean 28.4) metacrcariae per infected crayfish. These results suggest that P. westermani metacerariae are still transmitted by crayfish enzootically in southern Korea, and that freshwater crabs may transmit metacercariae only on rare occasions.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.220-229
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• 2021

This study is aimed to a textile design with a motif of korean endemic plants and a method for printing it in an eco-friendly manner. The floral pattern with the motif of korean endemic plants was designed using Illustrator and Photoshop program. CMYK color, which is the basic color of Digital Textile Printing (DTP), is based on natural dyes, and various colors, achromatic colors and pastel tones are applied. As a result, half-linen and cotton were suitable as a result of designing and applying a floral pattern of a korean special plants. Also, as a result of analyzing the printing effect by colorway and DTP for each material, it was printed uniformly and the washing fastness was good. However, fastness of color change showed low, indicating that a follow-up study was needed. This study contributes to environmental conservation through eco-friendly printing and the korean endemic plants will be interested in people around the world beyond korea.

• IMMUNE NETWORK
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• v.22 no.3
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• pp.23.1-23.12
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• 2022

Natural infection with severe acute respiratory syndrome-coronavirus-2 or vaccination induces virus-specific immunity protecting hosts from infection and severe disease. While the infection-preventing immunity gradually declines, the severity-reducing immunity is relatively well preserved. Here, based on the different longevity of these distinct immunities, we develop a mathematical model to estimate courses of endemic transition of coronavirus disease 2019 (COVID-19). Our analysis demonstrates that high viral transmission unexpectedly reduces the rates of progression to severe COVID-19 during the course of endemic transition despite increased numbers of infection cases. Our study also shows that high viral transmission amongst populations with high vaccination coverages paradoxically accelerates the endemic transition of COVID-19 with reduced numbers of severe cases. These results provide critical insights for driving public health policies in the era of 'living with COVID-19.'

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.95-97
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• 1986

서울에 소재한 육군장병의 검변에서 Fibricola의 충란 양성자 10명을 관찰하여 프라지관텔로 치료하고, 이 증 한례에서 Fibricola seoulensis의 성충 59마리, 요꼬가와홉충 68마리 및 Stellantchasmus fnlcatus 2마리를 관찰하였다

• Communications of the Korean Mathematical Society
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• v.22 no.4
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• pp.597-608
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• 2007

We present a general uniqueness result of an endemic state for an S-I-R model with external force of infection. We reduce the problem of finding non-trivial steady state solutions to that of finding zeros of a real function of one variable so that we can easily prove the uniqueness of an endemic state. We introduce an assumption which was usually used to show stability of a non-trivial steady state. It turns out that such an assumption adopted from a stability analysis is crucial for proving the uniqueness as well, and the assumption holds for almost all cases in our model.

• Development and Reproduction
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• v.25 no.1
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• pp.25-32
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• 2021

The main purpose of the current study was to obtain nuclear DNA content data among the representatives of the families and subfamilies of 31 endemic fishes that inhabit river of Korea. DNA contents of 31 endemic species were observed to rang from 1.5 to 4.8 pg DNA/nucleus. In Cyprinidae, DNA content of Abbottina springeri (1.5±0.03 pg DNA/nucleus) was the lowest value and DNA content of Carassius cuvieri (4.5±0.32 pg DNA/nucleus) was the highest value in all experimental groups. In Cobitidae, DNA content of Iksookimia longicorpa (3.9±0.17 pg DNA/nucleus) was the highest value and DNA content of Orthrias toni (1.5±0.18 pg DNA/nucleus) was the lowest value in all experimental groups. This study provides new information for a better understanding of the process of genomic evolution in 31 endemic species in river of Korea.

• Parasites, Hosts and Diseases
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• v.38 no.1
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• pp.33-36
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• 2000

A small-scale epidemiological survey was undertaken during 1997-1998 on the residents along the Osib-chon (Stream), Samchok-shi (City), Kangwon-do (Province), to evaluate the status of Metagonimus yokogawai infection. A total of 165 fecal samples was collected and examined by cellophane thick smear and formalin-ether sedimentation techniques. The egg Positive rate of M. yokogawai was 29.7%, showing a remarkable difference between males (46.6%) and females (16.3%). To obtain the adult flukes of M. yokogawai, 11 egg positive persons were treated with praziquantel and purged with magnesium sulfate. A total of 242,119 adult flukes (average 22,010 per person, 367 119,650 in range) was collected from diarrheic stools, all of which were identified as M. yokogawai. The results show that M. yokogawai is still highly endemic in this area.

• Parasites, Hosts and Diseases
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• v.38 no.1
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• pp.9-15
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• 2000

A scanning electron microscopic study was performed on the surface ultrastructure of metacercariae and adults of Metagonimus takahashii. Metacercariae were collected from the scale of crucian carp (Carassius auratus) , and adult flukes were harvested 1-4 weeks after infection to rats. In excysted metacercariae. the oral sucker had type I (numerous) and type II (seven in total) sensory papillae. Tegumental spines were dense and digitated into 5-7 points on the surface anterior to the ventral sucker, but became sparse and less digitated posteriorly toward the end of the body In adults, seven type II sensory papillae were characteristically arranged around the lip of the oral sucker, and on the inner side of the lip four small and two large type I sensory papillae were symmetrically seen on each side (12 in total). Tegumental spines on anterior two-thirds of the body. were digitated with 9-12 tips ventrally and 8-13 tips dorsally. Sperms entering into the Laurer's canal were observed. The results show that the surface ultrastructure of M. takuhashii is generally similar to those of M. yokogawai and M. miyatai except for the digitation of tegumental spines.

• Parasites, Hosts and Diseases
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• v.43 no.4 s.136
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• pp.129-134
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• 2005

To determine the status of Enterobius vermicularis infection among children living on western and southern coastal islands of the Republic of Korea, children (3-10 years) in 39 kindergartens and primary schools were examined using the cello-tape anal swab method, during July and August 2000. Of 1,661 children examined, $307(18.5\%) $were found to be positive for E. vermicularis eggs. The highest infection rate $(59.3\%)$ was found in a kindergarten and a branch school of Shinyang primary school on Chujado, Jeju-do (Province), Remarkable differences in egg positive rates were observed in different localities. The egg positive rate for boys $(21.3\%)$ was significantly higher than that of girls $(15.4\%)$ (P=0.02). However, positive rates were not significantly dependent on age. The results of the present study show that E. vermicularis infection is highly prevalent among pre-school and primary school children living on the western and southern coastal islands of the Republic of Korea, and indicate the need for efforts to control this infection.