• Journal of agricultural medicine and community health
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• v.5 no.1
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• pp.28-33
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• 1980

This study was undertaken to evaluate the present status of A. lumbricoides infection in a rural area of Korea. The 307 residents of all age group in Gumsa Myun, Yeo Ju Gun were examined by Kato's cellophane thick smear technique. Pyrantel pamoste was administered to the Ascaris infection cases by a single dose of 5mg/kg of body weight. The whole amount of 24 hour stool during two or three consecutive days were collected sepatately. The expelled A. lumbricoides worms from the unfiltered stool remnants were collected. They were measured by the length and weight, and the sex of the worms were differentiated. The results are as follows: 1) The incidence of A. lumbricoids infection of the 307 specimens examined was 40.1%(male: 40.9%, female:39.0%). The difference according to guman sex distribution was not statistically significant. 2) Seventy two Ascaris infected cases expelled 163 worms of various size. The mean number of worms per infected case were calculated as 2.3. The sex ratio of examined female and male Ascaris was 1.5:1 3) Among the expelled 97 female worms, the genital girdle were found in 60 female worms(61.9%). Genital girdle of gemale worm was located from the head in the position of $38{\pm}4$ of total length 100. 4) The average body length of male Ascaris was $16.3{\pm}3.1cm$ and female Ascaris was $21.7{\pm}3.5cm$ 5) The relationship between the weight(Y) and the length(X) of individual Ascaris worm was plotted. Y(gm).0.32$\fallingdotseq$(cm)-3.1 in female and Y(gm)$\fallingdotseq$0.1X(cm)-0.1 in male.

• Parasites, Hosts and Diseases
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• v.33 no.1
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• pp.1-8
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• 1995

Gymnophalkides seoi has drawn medical attentions since the discovery of the first human case and a highly endemic area on a southwestern coastal island of Shinan- gun, Korea. Marine bivalves especially oysters were strongly suspected as the source of infection. In this study the oysters, Crassostrea girns, naturally produced (rom the endemic area were examined whether they contain gymnophallid metacercariae. All of 50 oysters examined were infected with the metacercaviae of a gymnophallid, with the metacercarial density per oyster of 610 on average (2-4,792 in range). Later they were identified as G. seoi by obtaining adult worms from experimental mice. The metacercariae were unencysted, and firmly attached on the mantle surface of the oysters with their oral sucker. In sectioned specimens they were equipped with the ventral pit, a peculiar organ of the genus Gymophalloides, and non-muscular genital pore which was connected dorsally to the seminal vesicle. The seminal vesicle was in a great majority mono-sac. By this study, it has been confirmed that the oyster is a 2nd intermediate host of G. seoi as well as the major source of human infection with this fluke.

• Fisheries and Aquatic Sciences
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• v.25 no.12
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• pp.601-618
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• 2022

The genus Semisulcospira is an economically and ecologically valuable freshwater resource. Among the species, Semisulcospira coreana, Semisulcospira forticosta and Semisulcospira tegulata are endemic to the Korean peninsula and Semisulcospira gottschei is widespread in Asia. Therefore, maintenance and conservation of wild populations of these snails are important. We investigated the genetic diversity and population structure of Semisulcospira based on the mitochondrial cytochrome c oxidase subunit I (COI), NADH dehydrogenase subunit 4 (ND4), and combined mitochondrial DNA (COI + ND4) sequences. All four species and various genetic makers showed a high level of haplotype diversity and a low level of nucleotide diversity. In addition, Fu's Fs and Tajima's D neutrality tests were performed to assess the variation in size among populations. Neutrality tests of the four species yielded negative Fu's Fs and Tajima's D values, except for populations with one haplotype. The minimum spanning network indicated a common haplotype for populations of S. coreana, S. tegulata and S. gottschei, whereas S. forticosta had a rare haplotype. Also, genetic differences and gene flows between populations were assessed by analysis of molecular variance and using the pairwise fixation index. Our findings provided insight into the degree of preservation of the species' genetic diversity and could be utilized to enhance the management of endemic species.

• Korean Journal of Environment and Ecology
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• v.15 no.4
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• pp.401-407
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• 2002

Fishfauna were investigated in the Taebaeksan area streams. At the upper tributary of the Han River, 8 species of 4 families were collected and the dominant species was Rynchocypris oxycephalus. The two species, Rynchocypris kumgangensis and Silurus microdorsalis were Korean endemic species. Brachymystax lenok tsinlingensis, designated as a natural monument and vulnerable species was confirmed at the Jeongam-sa area streams At the upper streams of the Nakdong River, collected fishes were identified as 14 species of 7 families. The dominant Species was R. oxycephalus and subdominant Zacco temmincki. Korean endemic species were 8species(51.7%), Coreoleuciscus splendidus, Squalidus gracilis majimae, Microphysogobio yaluensis, Niwaella multifasciata, Silurus microdorsalis, Liobagrus mediadiposalis, Coreoperca herzi and Odontobutis platycephala. Brachymystax lenok tsinlingensis were confirmed at the Hyundong-Chon Stream and Baek-chon stream.

• Korean journal of applied entomology
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• v.38 no.1
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• pp.1-10
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• 1999

According to zoogeographic analysis, distribution types of Korean species of the subfamily Tryphoninae are as follows; Holarctic species (9.6%), Transpalearctic (38.4%), Transpalearctic-Oriental (8.2%), Eastern Palearctic (Trans-Far East Asia)-Oriental (4.1 %), Eastern Palearctic (17.8%) and Endemic (21.9%). Because of large numbers of palearctic and endemic species, we believe that the Korean Tryphoninae may have originated from northern hemisphere. The oldest fossil species of the Tryphoninae are the Catachoru rninor Townes and Urotryphon pusillus Townes in Creataceous amber from the peninsula Taimyr, Siberia. The world-wide distribution of the Tryphoninae appears to coincide with the continental movement.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.4
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• pp.43-62
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• 2015

The purpose of this study is to offer the raw data for management and conservation of Korean ecosystem by surveying the present conditions and characteristics of flora to select the ecological and landscape conservation area, Ilwolsan(Mt.), Korea. The numbers of flora in Mt. Ilwol were summarized as 582 taxa including 94 families, 307 genera, 508 species, 4 subspecies, 61 varieties and 9 formas. The rare plants were 15 taxa including Clematis koreana, Aristolochia contorta, Daphne pseudomezereum var. koreana, Iris odaesanensis and so forth. The Korean endemic plants were 14 taxa including Pseudostellaria coreana, Philadelphus schrenckii, Galium koreanum, Weigela subsessilis and so forth. The specific plants by floristic region were 29 taxa including Cimicifuga heracleifolia, Parasenecio firmus, Sorbaria sorbifolia var. stellipila, Acer mandshuricum, Syringa reticulata var. mandshurica and so forth. The naturalized plants were 22 taxa including Fallopia dumetorum, Rumex nipponicus, Trifolium repens, Sonchus asper, Phleum pratense and so forth. A set of important area is rare plant, Korean endemic plant, specific plant emerge a lot of areas.

• Korean Journal of Plant Taxonomy
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• v.50 no.1
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• pp.22-26
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• 2020

Chrysosplenium aureobracteatum Y. I. Kim & Y. D. Kim (Saxifragaceae) is a recently described endemic species growing in the central part of the Korean peninsula. It requires constant monitoring for conservation due to its limited distributions. There is also a need for molecular markers for proper assessments of the genetic differentiation of C. aureobracteatum from species morphologically similar to it. In this study, we developed microsatellite markers that can be used to evaluate the genetic diversity of this species, representing fundamental data with which to conserve the natural populations of the species. A total of 17 expressed sequence tag-simple sequence repeat (EST-SSR) markers were developed by the Illumina pair-end sequencing of the transcriptomes of C. aureobracteatum. These markers were successfully applied to populations of C. aureobracteatum and to its most closely related species, C. barbatum, revealing high polymorphism in both species. The EST-SSR markers developed in this study were proven to be useful not only to monitor the population genetic structure of C. aureobracteatum for conservation purposes but also to study the genetic delimitation of the species from species closely related to it.

• Development and Reproduction
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• v.22 no.1
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• pp.1-8
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• 2018

The annual reproductive cycle of the Korean endemic slender catfish, Silurus microdorsalis, was examined histologically regarding water temperature and day length of habitat, gonadosomatic index (GSI), and development characteristics of female and male gonads. The maximum GSI value was found in May, $1.23{\pm}0.33$ and $11.77{\pm}3.23$ for male and female respectively (habitat water temperature $21.5^{\circ}C/13.59hr$ day length). On the other hand, the minimal level was $0.63{\pm}0.10$ in July ($26.5^{\circ}C/14.17$) for male and $1.36{\pm}0.08$ in October ($20^{\circ}C/11.2hr$) for female. We compared and calculated the stages of testis and ovary development process in order to determine the germ cell development characteristics and the reproductive cycle. According to results, we classified the annual reproductive cycle of the slender catfish into five stages: Growing phase (December-February), Mature phase (March-April), Ripe and spawning phase / Releasing phase in male (May-June), Degenerative phase (July-August), and Resting phase (September-November).

• Korean Journal of Plant Taxonomy
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• v.53 no.2
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• pp.102-109
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• 2023

The basic information of ovule and seed characteristics was investigated for five monotypic and endemic genera in the Korean peninsula as categorized by the Flora of Korea category. The carpels and seeds were sectioned with a rotary microtome. Mature seeds were coated with platinum using an ion sputter and observed using a scanning electron microscope. As a result, Abeliophyllum was found to be anatropous and a unitegmic ovule, with a slightly colliculate seed surface and exotestal seed coat type. The ovule of Coreanomecon was anatropous and bitegmic, having a distinct echinate seed surface, and exo-endotestal seed coat type with a prismatic crystal in the mesotesta. The ovule of Hanabusaya was anatropous and a unitegmic, with a long reticulate seed surface sculpture, and distinct exotestal seed coat type. In addition, a wing developed at the opposite side of the raphe bundle. Megaleranthis was an anatropous and bitegmic ovule, having a small pentagonal disk shape, a concave seed surface and exotestal seed coat type. Finally, Pentactina was also anatropous and a unitegmic ovule, reticulate seed sculpture, and endotestal seed coat type. These data will be proving to be a source of good information for securing bio-sovereignty in the near future.

• Parasites, Hosts and Diseases
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• v.39 no.2
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• pp.85-118
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• 2001

Studies on Gymnophalloides seoi (Digenea: Gymnophallidae) and human infections are briefly reviewed. This minute intestinal fluke was first discovered from a Korean woman suffering from acute pancreatitis and gastrointestinal troubles. It was described as a new species by Lee, Chai and Hong in 1993. The southwestern coastal village where the patient resided was found to be a highly endemic area, and additional endemic areas have been identified. The parasite is very small, 0.33-0.50 mm long and 0.23-0.33 mm wide. and characterized by the presence of a ventral pit. The first intermediate host remains unknown, but the second intermediate host has been found to be the oyster Crassostrea gigas. Man and the Palearctic oystercatcher Haematopus ostralegus have been shown to be natural definitive hosts , and wading birds including the Dentish plover Charadrius alexandrinus are highly susceptible to experimental infection. Gerbils, hamsters, cats, and several strains of mice were also susceptible laboratory hosts. In experimentally infected mice, the parasites inhabit the small intestine, pinching and sucking the root of villi with their large oral suckers, but they did not invade beyond the mucosa in immunocompetent mice. However, they were found to invade the submucosa in immunosuppressed mice. Human G. seoi infections have been found in at least 25 localities; 23 islands on the Yellow Sea or the South Sea, and 2 western coastal villages. The highest Prevalence was found in a village on Aphaedo. Shinan-fun (49% e99 Positive rate) : other areas showed 0.8-25.3% prevalence. Infected people complained of variable degrees of gastrointestinal troubles and indigestion. The infection can be diagnosed by recovery of eggs in the feces; however, an expert is needed to identify the eggs. Praziquantel, 10mg/kg in single dose, is effective for treatment of human infections. Eating raw oysters in endemic areas should be avoided.