• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.3
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• pp.161-166
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• 2002

The ultrastructural characteristics of epidermis isolated from healthy and rusty ginseng roots(Panax ginseng) were observed by scanning electron microscopy (SEM), and the distribution profiles of inorganic elements were also examined by energy dispersive X-ray analysis (EDX). The epidermis of rusty ginseng was thick and cell walls were also severely disrupted whereas the epidermal image of healthy ginseng showed relatively thin, clear and rectangular structure. A high amount of rod-shaped bacteria was found in rusty ginseng and cells near bacteria were degraded. The bacterial density in epidermis of rusty ginseng was ranged from 2.9$\times$10$^{6}$ to 3.5 $\times$ 10$^{7}$ CFU/g fresh weight, while that of healthy ones was from 4.7$\times$10$^2$ to 1.2$\times$10$^3$CFU/g. Artificial inoculation of bacteria isolated from rusty ginseng induced similar symptom like rusty ginseng. The mineral contents inculding Al, Si and Fe were Higher in the epidermis of rusty ginseng, but K content was lower compared to healthy ones.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.47-58
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• 1985

An experimental study was performed to observe the in vivo effects of praziquantel on the light and scanning electron microscopic morphology of Fibricola seoulensis. The metacercariae were obtained from the snakes and 1, 000 in each number was orally given to total 15 albino rats; 5 controls and 10 treatment group. Seven days later the 10 rats were treated with 10 mg/kg praziquantcl and sacrificed 1~24 hours later to search for the worms from their small intestines. The major light microscopic changes in the drug-exposed worms were early contraction followed by relaxation of especially their forebody, vacuolization of the tegument and subtegumental parenchymal layers, and narrowing of the intestinal lumens. The scanning electron microscopic findings were characterized by formation of numerous blebs followed by rupture and subsequent destruction of their whole teguments. These results show that the change in worm body is not confined to the tegument but extends to deeper parenchymal portions and also occurs in their intestines. It is suggested that the drug uptake by the worms should be either through their tegument or through the digestive tract.

• Journal of fish pathology
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• v.3 no.2
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• pp.61-66
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• 1990

Experimental infection and histopathological study using a deleterious aquatic fungus (Saprolegnia diclina type I) were carried out in the eels (Anguilla japonica) to know what pathological changes the fungus would produce in the affected eels. The eels in group A and B which were treated with fish net were not susceptible to experimental infection. In group C which the cuticle was scraped by artificial treatment, the aquatic fungi were invading all the eel bodies including the desquamated lesions. Histopathologically, the affected eels were markedly reduced in number of goblet cells and showed moderate damage of the clavate cells. Nodular formation involving ecchymotic hemorrhage was seen in some affected areas. The eels survived to 25 days after experimental infection.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.892-899
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• 1995

A numerical simulation program based on the finite elerrent method is developed for calculating electromagnetic field of the cylindrical electromagnetic pump. The calculated results by the developed program show that Lorentz forces show maximum peak at an optimum length ($L_c$) of the induction coil. The value of $L_c$ depends on the radius of the molten metal when the skin depth is large. On the other hand, the value of $L_c$ depends on the skin depth when it is small.

• Journal of Plant Biology
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• v.38 no.1
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• pp.73-78
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• 1995

리기다소나무 추출액을 농도별로 무와 차풀에 처리한 3일 후에 광학현미경을 이용하여 근단세포를 관찰할 경우 6% 처리구에서는 피층세포가 신장되었으나, 25%, 75% 처리구에서는 오히려 세포 표면이 위촉되어 불규칙하게 변화됨으로써 표면부 전체가 심한 굴곡현상을 나타내었다. 특히 차풀에 있어서 75% 처리구의 표피층은 작고 불규칙한 세포들로 상당히 비후되어 있었다. 투과전자현미경으로 근단의 세포를 관찰한 결과 무의 처리구는 대조구에 비하여 표피세포의 원형질막 함입현상이 활발하였고 세포벽은 전자밀도가 높은 과립들이 층상으로 분포해 있었다. 피층세포와 중심주의 유세포에서는 중앙 액포가 발달하였고 지질과립이 감소하였으며 전분형성체가 자주 관찰되었다. 차풀의 처리구는 대조구에 비하여 세포질의 퇴행현상이 심화되었고 일부 잔존한 세포질내에는 중앙 액포가 발달하였는데 그 액포막의 안쪽에는 높은 전자밀도의 물질이 축적되었으며 피층세포와 중심부의 유세포에서는 전분형성체가 뚜렷이 존재하였다.

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.165-172
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• 1995

A transmission electron microscopic study was performed on the ultrastructure of the tegumental layer of GymophoLloines seoi (Digenea: Gymnophallidae) metacercarlae and adults. The metacercariae were obtained from naturally infected oysters, Crcssosoea gigas, and the adults from experimentally infected C3H mice. The tegumental layer generally revealed a small number of foldings, numerous small vacuoles, sines, and muscle bundles. Beneath the muscle layer, nuclei of the tegumental cells were located. There was little difference in the structure of the tegument between the metacercariae and adults. The oral sucker, having well-developed muscle layers, showed a similar structure to the ventral sucker except numerous foldlngs in the ventral sucker. The ventral pit was surrounded by a thin spcpiu layer, where a number of microtubules and mitochondria were seen. Around the ventral pit located well-developed circular and longitudinal muscles. The results showed that the ultrastructure of the tegumental layer of G. seoi metacercariae and adults revealed little difference from other trematodes in general. The ventral pit, a peculiar structure of this trematode, seems to function as a sphincter or an accessory adhesive organ.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.303-318
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• 1995

Microscopic structures of epidermis and palynology and isozyme analysis were examined to find out the intergeneric and interspecific relationships and consequently to confirm the position of Hanabusaya aiatica as an endemic genus among 4 genera and 9 species belonging to the Hanabusaya asiatica, Korean endemic, and its allied groups. In the examination of microscopic structures of epidermis, cell patterns of perianth and ultrastructure of seed coat were found to be useful characters for the identification of the 4 genera and 9 species. Palynological characters such as microscopic structure and overall morphology of pollen grains were, however, not enough to distinguish them because of the great variabilities in these traits. Isozyme analysis showed that H. asiatica was very closly related to Campanula punctata and C. takesimana, though there were variations among populations and collected areas in some classified groups, depending on classified groups. Based on these results, the position of H. asiatica as an endemic genus was well confirmed.

• Journal of Yeungnam Medical Science
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• v.1 no.1
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• pp.185-190
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• 1984

Toxic epidermal necrolysis is a reactive erythema of nonstaphylococcal origin characterized by a scalded appearance of the skin. The TEN is widely regarded as a variant of severe erythema multiforme because of its acute course, its freguent common cause, its freguent overlap with Stevens-Johnson disease, and its histologic identity. I present a case of TEN with severe mucosal involvement resembled Stevens-Johnson disease.

• Applied Microscopy
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• v.37 no.2
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• pp.83-91
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• 2007

The present study examined the epidermal changes of adhesive disks which occur during attachment in Parthenocissus tricuspidata using scanning and transmission electron microscopy. Several adhesive disks, each covered with a bract, develop from the shoot apical meristem during early development. In the initial stage, the adhesive disks are club-shaped and their upper and lower epidermis are indistinguishable. However, in the actively growing stage, they become spherical and both epidermis are clearly differentiated into the adventitious roots. Prior to wall attachment, the adhesive disks exhibit adaxial convex and abaxial concave shapes, and electron-dense substances are abundant in the vacuoles of epidermal cells. The peripheral area of the adhesive disk is adhered first to the wall surface, while the central area is drawn inward in a vacuum-like state during attachment. As the attachment progresses and the electron-dense substances continue to discharge, the upper and lower epidermis rapidly undergo deterioration and the disks shrink considerably. At this stage, structural changes of the lower epidermis occur much faster than in the upper one. The discharged substance is accumulated on the wall surface, and this aids the attachment of adhesive disks on the wall for long periods. In this manner, the shape and structure of the adhesive disk epidermis change drastically from initial growth to the mature stage. Further, the role of electron-dense substance and shrinkage of the disk during attachment has been discussed in Parthenocissus tricuspidata.

• Journal of Plant Biology
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• v.38 no.1
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• pp.79-86
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• 1995

Visible injury symptoms such as necrosis, chlorosis and premature senscence in the leaves of Ginkgo bloba and Pinus thunbergii treated with acid rain of pH 3.2 or below were observed. The epicuticular wax erosions were observed by SEM after exposure to acid rain of pH 2.4 and 3.2 in G. biloba and pH 4.0 below in P. thunbergii. The adaxial epidennal cells and sponge parenchyma cells were compressed, and those were distorted in the leaves of G. biloba treated with simulated acid rain of pH 3.2 or below. However, vascular tissue was intact. With increase of acidity, mesophyll cells were smaller than those of control while intercellular space in mesophyU was increased. In P. thunbergii, sponge parenchyma cells and vascular tissue except epidennis were distorted after exposure to acid rain of pH 2.4. The size change of stomata in foliar injury was not observed, but the stomatal index and size of stomatal aperture in leaves treated with acid rain increased. The stomata of injured leaf were opened in both species examined.amined.