• 한국지반공학회지:지반
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• 제9권3호
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• pp.5-22
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• 1993

우리나라의 화강암 풍화토(CW와 RC풍화등급)의 불교란시료에 대한 일련의 토질물성 및 역 학적 특성실험이 수행되었다. 화강암 풍화토는 크게 CW 및 RS 풍화등급으로 나뉘어지며, 풍화가 많이 진행됨에 따라서 토질 물성이 매우 예민하게 변화하고, 일축압축강도 및 전단강도지수도 급격히 감소할 뿐만 아니라, 또한 변형특성은 풍화가 많이되고 침수됨에 따라서 화강암풍화토가 점차로 ductile하고 plastic하게 변해가는 특성이 있다. 또한 화강암 풍화토는 침수가 됨에 따라서 특이한 성질이 있는 것으로 관찰되었다: (1) 전단강 도(특히 점착력) 및 일축압축강도가 급격히 감소할 뿐만 아니라, (2) 물과의 반응시에 화강암 풍 화토의 입자가 쉽게 약해져서 더욱 작은 입자크기로 분해된다.

• Parasites, Hosts and Diseases
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• 제41권1호
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• pp.27-33
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• 2003

The developmental features, growth and organogenesis of Macroorchis spinuiosus were observed in albino rats. Globular and thick walled metacercariae, possessed a stylet, Y-shaped excretory bladder and extracecal testes. Un albino rats, M. spinulosus showed habitat shifting. The majority of M. spinulosus reside in the jejunum for the first four days post Infection (p.i.) and migrate to the duodenum at the later stage of infection. M. spinulosus grew rapidly during the first four days and reached full maturity at 14 days p.i. and later reduced in size. The ovary was separated from the genital primodium at one day p.i. The seminal vesicle appeared on the third day and divided into two sacs on the fourth day p.i. and intrauterine eggs and sperm mass were produced on the fourth day. Organogenesis and enlargement of reproductive organs governed the growth of M. spinulosus. The similarity of related species of the genus Macroorchis to M. spinulosus was discussed In consideration to developmental features.

• 한국수산과학회지
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• 제50권1호
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• pp.48-54
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• 2017

The ecological characteristics of Pseudoblennius cottoides were investigated off Dolsan Island, Yeosu, Korea, from June to December, 2001. Their habitats were the reef zone and surrounding embankment which was covered with seaweeds. Their range of total length (TL) was 6.10-8.40 cm (n=15), and the individuals (over 8.10 cm) of them accounted for in June. It was 8.60-15.7 cm (n=67), and the individuals 11.1-12.0 cm in TL accounted for in October, 2001. The female to male sex ratio was 1:0.48 (n=185). The gonads were in the shape of a rod and the ovaries were large in size. In June, the histology of the seminiferous tubules was observed. In August, the testicles appeared. In October, spermatocyte was observed in the testes, and ovaries were observed in relation to circumference popularity and oocyte.

• Parasites, Hosts and Diseases
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• 제23권2호
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• pp.230-235
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• 1985

The metacercariae of an echinostomatid fluke were detected from a freshwater 6sh, Odontobutis obscura interrupta caught from the Seom river system, Wonseong-gun, Kangwon-do, and experimentally infected into rats to obtain the adult worms for the species identification. A total of 32 metacercariae was detected from 10 fishes (27.8%) out of 36 O. obscura interrupta caught from the river. The average size of metacercariae was $153.4{\times}149.0{\;}{\mu}{\textrm{m}}$. Also, it was uniquely specific that thickened membrane was formed around the metacercarial cyst wall. The rats orally infected with those metacercariae were sacrificed 20 days after infection to get the adult worms. The mean length and width of the adult worms were 0.75 cm and 0.13 cm, respectively. The number of collar spines on circumoral disk was 26 to 28, and the end group spines at lateral sides of the oral sucker were 4 on each side. The echinostomatid flukes observed in this study were all identified as Echinostoma hortense according to the morphologies of the cirrus sac, ovary, vitellaria and testes of the adult worms and the shape of eggs. On the other hand, O. obscura interrupta is one of the fresh-water fish that are preferably eaten raw by the rural inhabitants. Although no human case of 5. hortense infection by eating O. obscura interrupta has been experienced yet, the possibility is strongly suggested in this study.

• Parasites, Hosts and Diseases
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• 제56권5호
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• pp.501-507
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• 2018

We described here the morphological characteristics for the species identification and fish hosts of Isoparorchis sp. (Digenea: Isoparorchiidae) in the Republic of Korea (Korea). Total 1,371 freshwater fishes collected in Yangcheon (Stream) in Sancheong-gun, Gyeongsangnam-do were examined by the artificial digestion methods to survey the infection status of digenetic trematode metacercariae for 4 years (2013-2016). Adult and larval worms of Isoparorchis sp. were detected in 38 (8.4%) out of 451 fish in 4 species, i.e., Pungtungia herzi, Acheilognathus koreensis, Squalidus japonicus coreanus and Odontobutis platycephala, examined. The infection density was 1.1 worm per fish infected. They were mainly found in the subcutaneous tissues and abdominal cavities. Nodules with worms in the subcutaneous tissues were revealed as the blue ink-colored bulges. Adults leaf-like, $21.6{\times}9.84mm$ in average size. The ratio of body length to body width was 2.20: 1. Oral sucker subterminal, $1.03{\times}1.22mm$. Pharynx muscular, $0.55{\times}0.54mm$. Esophagus very short. Ceca convoluted, terminated near the posterior end. Ventral sucker anterior 1/3.75, $1.99{\times}2.10mm$. The ratio of ventral sucker to oral sucker was 1.74: 1. Testes round to elliptical, both sides of ventral sucker, $1.43{\times}1.33mm$. Vitellaria highly dendritic, posterior 1/3 level. Eggs operculated, embryonated, $52{\times}32{\mu}m$ in size. By the present study, 4 fish species aforementioned are to be listed as the fish hosts of Isoparorchis sp. in Korea and additionally the morphological characteristics are to be described for the species identification.

• Parasites, Hosts and Diseases
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• 제54권4호
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• pp.485-496
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• 2016

We describe 2 echinostome species recovered from an Eastern cattle egret, Bubulcus ibis coromandus, from Cheongju-si (city), Chungcheongbuk-do (province), Korea. Total 72 Pegosomum bubulcum specimens were recovered from the bile duct. They were $7,566{\times}2,938{\mu}m$ in average size and had 27 collar spines with vitelline extension from anterior 1/3 level of the esophagus to mid-level of the posterior testis as characteristic features. Total 9 specimens of Nephrostomum ramosum were recovered in the small intestines of the bird. They were ribbon-shaped, $11,378{\times}2,124{\mu}m$ in average size, and morphologically variable in some organs, i.e., the number of collar spines (47-50), the shape of ovary and testes, and the extension of vitelline follicles. These morphological variations observed in a single host indicated that these features are not critical for the classification of Nephrostomum species and thus were reconsidered taxonomically as synonym of N. ramosum. This study is the first report documenting and describing both flukes and their associated genera in Korea.

• Parasites, Hosts and Diseases
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• 제55권3호
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• pp.341-345
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• 2017

The metacercariae of Artyfechinostomum malayanum (Leiper, 1911) Mendheim, 1943 were discovered in Pila sp. snails purchased from a market in Phnom Penh, Cambodia. They were isolated from the snails using the artificial digestion technique and were orally fed to 2 hamsters, 1 rat, and 2 mice to obtain the adult flukes. The metacercariae were round, $145-165{\mu}m$ in diameter, having a cyst wall of $6-10{\mu}m$ in thickness, a head collar and collar spines, and characteristic features of excretory granules. Adult flukes were recovered in the small intestines of the animals at days 14 and 32 post infection and were morphologically observed using a light microscope and a scanning electron microscope. They were plump or elongated, ventrally curved, $6.0-8.1{\times}1.6-2.0mm$ in size, and characterized by the head collar bearing 43 collar spines, including 5 end group ones on each side, a long cirrus sac extending beyond the posterior margin of the ventral sucker, a submedian ovary, and 2 deeply lobed testes. Eggs in uteri were operculate, ovoid to ellipsoid, and $120-135{\times}68-75{\mu}m$ in size. In scanning electron microscopy, the head collar was prominent with collar spines looking like horns. Scale-like tegumental spines were densely distributed on the ventral surface between the head collar and ventral sucker. Sensory papillae were distributed mainly on the tegument around suckers. By this study, it has been first confirmed that the life cycle of A. malayanum exists in Cambodia.

• Parasites, Hosts and Diseases
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• 제30권4호
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• pp.237-244
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• 1992

Meterchis orientalis의 병아리 숙주내 감염력 및 성장발육상을 알아 보고 성충의 형태학 적 특징을 관찰하였다. 참붕어로부터 분리 수집한 피리유충을 부화된지 3일된 병아리 40마리에 각각 100개씩 경구감염시킨 후 1.5, 3, 5, 7, 9, 11, 14일 및 21일에 충체를 누수하여 고정, 염색, 탈수 및 봉입 등의 과정을 거친 다음 관찰 및 계측하였다. 총체는 모두 병아리의 담낭에서 발견되었으며 평균 32U의 회수율을 나타내었다. 감염 후 9일까지는 비교적 완만히 성장하였으나 9일에서 11일 사이에는 급속히 성장하였고 11일에서 14일 사이에 다시 성장이 둔화하였으며 21일에 회수한 충체는 14일된 충체보다 크기가 작았다. 감염 후 1.5일파 5일에 요수한 충체에서는 비생식기관과 생식원기가 관찰되었고 5일된 충체에서는 비정형적인 난락와 엽상의 고구이 관찰되었으며 이후 차차 발육하여 감염 후 11일에 회수한 충체들은 완전히 성숙하였다. 성숙한 충체는 나뭇잎 모양이었으며 1∼3굽이의 저정낭, 타원형의 난소, 주머니 모양의 수정낭,517엽의 고환 및 소포형의 난황선 등을 보유하고 있었다. 충란은 평균 31.gx15.Sum 크기이었고 최대 폭이 가운데 지점에 있었으며 난개 반대편의 난각이 비후되어 있었다. 이상의 결과로 병아리가 M orienta비의 새로운 숙주로 추가되었고 이 흡충이 병아리 내에서 감염 후 21일까지 sigmoid형으로 성장하며 성충이 되기까지는 l1일 정도가 소요됨을 알 수 있었다.

• 대한수의학회지
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• 제37권2호
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• pp.425-438
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• 1997

To assess the testicular toxicity induced by DA-125, a new anthracycline anticancer agent, the test substance was intraveneously administered to male beagle dogs at dose levels of 0, 0.0023, 0.0375, 0.15, and 0.6 mg/kg/day, 6 days a week for 26 weeks. At 0.6 mg/kg/day, 1 out of 3 dogs had died on day 42 of treatment and the other dogs were sacrificed on days 46 and 122 of treatment due to the increasingly severe clinical condition. Clinical signs considered to be related to treatment were included anorexia, vomiting, salivation, decreased activity, mucous and/or dark faeces, diarrhea, and swelling, abscess and/or ulceration of injection sites. Suppression in body weight gain, reduction in food intake, decreases in testicular weight and size, and hemorrhage of epididymis were also observed in male dogs. Microscopically, severe degenerative changes such as atrophy of seminiferous tubules, loss of germ cells, degeneration of germ cells, vacuolization of Sertoli cells, and hyperplasia of Leydig cells were observed in all dogs. Azoospermia in epididymal tubules, atrophy of epithelia in the cauda epididymis, and prostate atrophy were also found. At 0.15 mg/kg/day, anorexia, vomiting, salivation, diarrhea, and swelling of injection sites were observed. In addition, suppression in body weight gain and decreases in testicular weight and size were found in male dogs. Atrophy of seminiferous tubules, decrease of germ cells, degeneration, exfoliation and retention of germ cells, vacuolization of Sertoli cells, and hyperplasia of Leydig cells were observed by histopathological examination. Azoospermia in epididymal tubules and prostate atrophy were also found. At 0.0375 mg/kg/day, there were no clinical signs considered to be indicative of a reaction to treatment, but testicular size was significantly reduced. Microscopically, decreases in the number of spermatogonia and epidydimal speramtozoa were found. There were no evidences of general or testicular toxicity at 0.0023 mg/kg/day. These results indicate that DA-125 produces significant and persistent damage to the spermatogenic compartments of the testes in male beagle dogs.

• Parasites, Hosts and Diseases
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• 제57권6호
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• pp.657-664
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• 2019

We identified the echinostome metacercariae in Chinese mystery snails, Cipangopaludina chinensis malleata, from Xiengkhuang Province, Lao PDR with morphologies of adult worms recovered. Total 20 snails were examined with artificial digestion method and then the collected metacercariae were orally infected to a mouse and a rat. Adult worms recovered from experimental animals were observed with a light microscope and a SEM. The metacercariae were round, 125×123 ㎛ in average size, with a moderately thick cyst wall, collar spines distributed in the head collar and excretory granules in 2 canals of excretory tube. Adult flukes (3-week-old in a rat) were elongated, ventrally curved and 5.310×1.023 mm in average size. Head collar distinct, bearing 43 collar spines with 5 end group ones on each side. Oral sucker subterminal, prepharynx very short, pharynx well developed, and esophagus relatively short. Cirrus sac well developed, with a saccular seminal vesicle, and ventral sucker very large. Ovary round and on the median line of the body. Testes tandom and elongated. Eggs operculated, elliptical and 90×57 ㎛ in average size. In the SEM observation, the head crown prominent, with 43 collar spines resembled with horns of younger stag. Scale-like tegumental spines were densely distributed on the surface between the head collar and ventral sucker, and their densities were decreased posteriorly. Conclusively, the metacercariae detected in C. chinensis malleata from Lao PDR were identified as those of Echinostoma macrorchis based on the morphological characteristics of adult worms.