• The Plant Pathology Journal
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• 제18권1호
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• pp.43-49
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• 2002

Direct effects of atmospheric ozone on conidia of the rice blast pathogen, Magnaporthe grisea, were investigated to evaluate ozone-induced effects on infection potential of the rice blast fungus. Acute ozone exposure (200 nl $1^{-1}$, 8 h $day^{-1}$3 days) during sporulation significantly affected conidial morphology, appressorium formation, and disease development on rice loaves. Ozone caused reduction in conidial size and change in conidial shape. Relative cytoplasmic volume of lipids and vacuoles were increased in ozone-exposed conidia. Inhibition of appressorium formation and simultaneous increase in endogenous levee of polyamines were found in ozone-exposed conidia. The inverse relationship between appressorium formation and level of polyamines implies that ozone-mediated increase in intracellular level of polyamines may inhibit appressorium formation in rice blast fungus. Furthermore, rice plants inoculated with ozone-fumigated conidia exhibited less severe disease development than those with unfumigated conidia. This result suggests that the anti-conidial consequence of acute ozone will eventually weaken the rice blasts potential for multiple infection cycle. This further suggests that consequently, rice blast can be transformed from an explosive disease to one that has limited epidemiological potential in the field.

• 대한수의학회지
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• 제19권2호
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• pp.99-105
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• 1979

In order to know the histological changes of rat preputial gland during normal sexual cycle and sex hormone treatment, matured Wistar rats (B.W.about 200g) were used for the experiment. Rats were subcutaneously given $2{\mu}g$ 17-${\beta}$-estradiol (Sigma) and 2.5g progesterone (Nakarai Chem., Japan) daily in 0.5ml propylen glycol for ten days respectively. The results obtained are as follow: At the stage of estrus and metestrus, the eosinophilic crystalloid granules and large vacuoles in the acinar cells appeared numerously, and the excretory ducts were severely extended. The developed connective tissue between the acinus were also found. At the stage of proestrus and diestrus, however, the small vacuoles and a few eosinophilic crystalloid granules appeared in the acinar cell. In the estradiol treatment, on the other hand, severely extended excretory ducts and a small number of the eosinophilic crystalloid granules compared with the progesterone treatment were found. The cyst-like structure was found, and in that the acinus disappeared completely. In the progesterone treatment, remarkably extended excretory ducts and nomerous appearance of oval formed eosinophilic granules in the acinar cells were found. As these findings, it could be suggested that the secretion of rat preputial gland was active at the estrus and metestrus stage, and estrogen may concerned in the secretion, land progesterone in the formation of secretory products.

• Applied Microscopy
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• 제4권1호
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• pp.25-33
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• 1974

Glycine max Merr., Zea mays L.의 엽육세포와 근단세포에서 cytolysome의 기원과 기능에 관하여 추구하였다. Cytolysomes은 원형질막과 세포질의 소포체에서 유래되는데, 원형질막의 함입으로 다소포체인 것과 환상인 다층막성구조로 분화되는 두가지 기본형이 있고, 또 세포질에서는 무과입성 소포체가 세포질의 일부를 분리시키으로서 세포질분리체로 분화된다. 원형질막과 세포질에서 유래된 이들 구조는 각각 막성구조가 증가되면서 액포내로 유리되고 자식성소화과정을 밟아 퇴화되는것 같다.

• Animal cells and systems
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• 제9권2호
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• pp.65-73
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• 2005

In this study, we found that sperm ball of Urechis unicinctus consisted of a somatic cell and spermatogenic cells. After separation from the sperm ball, individual spermatid floated freely in the coelomic fluid and differentiated into a mature sperm. Because of many nuclear vacuoles, spermatid nucleus was observed to be heterogeneous. Later, the spermatid nucleus condensed into the homogeneous round nucleus of the mature sperm. Perinuclear microtubules could be seen but did not seem to be organized into manchette microtubules. To understand the nature of nuclear condensation during spermiogenesis, the sperm and spermatids (spermiogenic cells) were treated with FITC-phalloidin, or anti-actin-FITC, or labeled with antiactin immunogold particles (AAIP; 10 nm) followed by transmission electron microscopy or confocal laser scanning microscopy. The anti-actin-FITC and FITC-phalloidin reactions occurred distinctly in the nuclei of both spermiogenic cells. FITC-phalloidin reacted more intensely with acrosomes. The AAIP were incorporated mainly into nuclei of both cells sometimes showing local distribution in the nucleus. Nuclear vacuoles of spermatids disappeared progressively with condensation of the nucleus, as the number of incorporated $AAIP/{\mu}m^2$ increased. These results suggest that nuclear actin microfilaments might be closely related to nuclear condensation.

• Food Science and Biotechnology
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• 제15권6호
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• pp.833-837
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• 2006

To determine whether alcohol-treated rat liver cells can be protected by a static magnetic field (SMF), we analyzed the blood chemistry and histology of hepatic tissue removed from alcohol-exposed rats that had been exposed to a static magnetic field. The rats were exposed to a 0.3 tesla (3,000 gauss) magnetic field (MF) for 24 hr daily for 5 weeks with appropriate controls. Glutamic pyruvic transaminase activity and the triglyceride levels in animals exposed to the north (N) or south (S) pole of the MF decreased significantly (p<0.01 and p<0.05, respectively) compared with negative control animals with alcohol exposure. A histological examination of hepatic tissue revealed a moderate to severe accumulation of fat vacuoles of various sizes in the cytoplasm of the hepatocytes of animals in the negative control group throughout the study; whereas in groups exposed to the MF poles, fewer fat vacuoles were seen compared with the negative control group. Electron microscopic observations showed that exposure to the N or S pole protected organelles, including the nucleus, from damage during exposure to this toxic agent, as indicated by the fact that the nucleus and the mithochondria virtually retained their shape throughout this study. These results suggest that exposure to a SMF could be an excellent way of protecting against alcohol-induced damage to the rat liver cell.

• Applied Microscopy
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• 제17권1호
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• pp.76-82
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• 1987

생쥐 간세포(肝細胞)의 미세구조(微細構造)에 미치는 메틸수은(水銀)의 독성적(毒性的) 영향(影響)과 이에 대한 홍삼(紅蔘) 추출물(抽出物)의 해독효과를 전자현미경적(電子顯微鏡的)으로 연구하였다. 대조군(對照群)의 간세포(肝細胞)에 비하여 메틸수은(水銀)만을 투여(投與)한 군(群)에서는 핵(核)의 일부가 붕괴(崩壞)되고, mitochondria의 팽대(膨大), cristae의 수축(收縮) 내지 손실(損失) 및 다수의 대형 강포(腔胞)의 출현(出現)이 일어나고 glycogen의 양(量)이 감소되었다. 메틸수은(水銀)과 홍삼(紅蔘) 추출물(抽出物)을 병행(倂行) 투여(投與)한 군(群)에서는 메틸수은(水銀)만을 투여(投與)한 군(群)에서보다 mitochondria의 팽대(膨大) 정도(程度)가 적고 강포(腔胞)의 크기와 수가 감소되었으며 정상(正常) 세포(細胞)와 비슷한 상태로 나타났다.

• Applied Microscopy
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• 제9권1호
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• pp.1-11
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• 1979

Electron microscopic studies were carried out to investigate the fine structure of ommatidia of the compound eyes in Meimuna mongolica D. The crystalline cone appears round, and is composed of four double-membraned cone cells and surrounded by pigment cells having many pigment granules. The rhabdom is a closed type, and is composed of four rhabdomeres Its cross section reveals lamellated microvilli which are oriented in four different directions suggesting that these represent four photoreceptive sites. The microvilli, in a cross sectional view, are hexagonal in shape with a central axis inside. There are usually eight retinular cells arranged radially from the rhabdom, but in some retinular layers seven or nine retinular cells could be observed. The cytoplasm of each retinular cell is interconnected with that of microvilli of the rhabdomere, but the appearance of this interconnection varies depending on the number of retinular cells.'The retinlilar cells neighboring the microvilli seem to have well-developed perirhabdomal vacuoles and mitochondria as well as pigment granules surrounding these vacuoles.

• Applied Microscopy
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• 제7권1호
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• pp.1-12
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• 1977

Ultrastructural changes of Entamoeba histolytica, a concomitant strain YS-9, which was treated in the immune serum was examined. The amoebae in the serum became immobilized state from about 30 minutes of the treatment and recovered at about 60-90 minutes. In the cells of control group, helix structures were scattered throughout the cytoplasm. The particles comprising the helix structure averaged 20 nm in diameter. At the beginning stage of the immobilization, helical aggregates(chromatoid body) which associated with vacuoles appeared abundantly in the cytoplasm, but gradually tended to aggregate along peripheral region of the cell, specially in intactly immobilized state. Each parallel array of aggregates measured about 45 nm in width. When the cells became remobilize, pseudopodia appeared again, but helical aggregates disappeared and numerous helix structures were observed in the cell periphery. Distribution of glycogen particles showed no change, and acid phosphatase activities were seen in both the immobilized and the control group. The reaction was markedly noticed in the vacuoles.

• Journal of Species Research
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• 제9권4호
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• pp.455-461
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• 2020

Marine benthic ciliates were collected from four rocky intertidal pools along the eastern and southern coasts of Korea from 2012-2013. Ciliate specimens were examined by observing living and stained cells. Four ciliate species were new to Korea based on morphological characteristics as follows. (1) Aspidisca polypoda (Dujardin, 1841): small bean-shaped (ca. 30 ㎛), eight conspicuous dorsal ridge, polystyla-arrangement of frontoventral cirri; (2) Epiclintes auricularis auricularis (Claparède & Lachmann, 1858): tripartite and auriform body (ca. 300 ㎛), 46 adoral membranelles, one or two frontal and 23 transverse cirri, 12 oblique fronto-midventral rows; 59 left and 71 right marginal cirri; (3) Pseudochilodonopsis marina Song, 1991: reniform body (ca. 50 ㎛), two obliquely positioned contractile vacuoles, seven left and five right kineties, five fragmented preoral kineties; (4) Dysteria semilunaris (Gourret and Roeser, 1888): oval-shaped (ca. 30 ㎛), two longitudinally positioned contractile vacuoles, conspicuous longitudinal grooves on both plates, four or five right kineties, one short row below frontoventral kineties.

• Journal of Ginseng Research
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• 제15권2호
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• pp.131-138
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• 1991

This study was carried out to investigate the development of endoplasmic reticulum and the formation of Protein body in the endosperm cell during seed formation of Panax ginseng C. A. Meyer with electron microscope. In the endosperm cell of early developmental process after pollination, vesicles that contain storage materials produced in rough endoplasmic reticulum incorporated into central vacuole. The central vacuole is gradually subdivided into several small-sized vacuoles and increased in number. Amorphous proteinaceous materials of high electron density are produced in rough endoplasmic reticulum. Rough endoplasmic reticulum increase in number and surround the protein body and vesicles circularly. Spherical proteinaceous granules with limited membrane appeared from the amorphous granules at the peripheral region of the rough endoplasmic reticulum. Gradually, storage materials are accumulated within the vacuole surrounded by spherosomes. Protein bodies are formed by interfusing between vacuoles and vesicles derived from rough endoplasmic reticulum which contained the amorphous protein of high electron density.