• Applied Microscopy
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• v.42 no.1
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• pp.17-26
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• 2012

Histologic and microstructural changes during the postembryonic development of the wolf spider Arctosa kwangreungensis were studied using light and scanning electron microscopy to examine the relationship between a morphological differentiation and behavioral properties. The postembryo with abdominal yolk sac was stayed inactive in the egg case because its muscular and visual systems were not fully developed to a functional level. The first instar spiderlings, developed from the postembryo by a first molting process, started to exhibit its pigmentation on their body cuticles. In particular, undifferentiated cell clusters of central nervous system (CNS) were densely distributed within the cephalothorax, and highly differentiated abdominal ganglion was observed. They had a characteristic visual system looks more like its adult counterpart, and had segmented appendages looks more like the tiny spiders containing well oriented muscular system. After 3rd instar, spiderlings grew more rapidly with accordance to their consistent growth and periodical molting processes. Thus, the relative area of CNS with respect to cephalothorax was gradually decreased, instead a pair of venom glands, musculature, and connectives occupied the residual area. It has been revealed that the early development of spider can be controled by the feeding condition of larval period, since histologic and microstructural differentiations in both appendages and optic system were completed at the second instar. In particular, behavioral properties of the wandering spiders that depend on vision and their running ability were deeply related to physiological differentiation of the microstructural development.

• Journal of Life Science
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• v.16 no.5
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• pp.856-858
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• 2006

The study was carried out to develop efficiency of transformantion in pepper plants. We used cotyledons of two native varieties, 'Subicho' and 'Kumtap' to establish some conditions of plant regeneration. Differentiation rate of shoot was higher in 2 to 4 mg/l zeatin and 0.05 mg/l NAA than in other treatments. Meanwhile, differential rate of roots was the highest in 0.5 mg/l NAA.

• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.1
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• pp.25-30
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• 2000

The conditions for callus formation and plant regeneration were confirmed in Italian ryegrass (Lolium mulfiorum Lam.). Among SH (Schenk and Hildebrandt), MS (Murashige and Skoog) and N6 medium (Chu) MS medium was highest degree of efficiencies respectively in callus formation and plant regeneration. In this study, we determined volume of hormones and other compounds appended in media. For callus formation, only $5\;mg/\;{\ell}$ of 2,4-D (2,4-dichlorophenoxy acetic acid) was appended in their media. For plant regeneration, we used MS medium containing $1.0\;mg/\;{\ell}$ of BA and $0.1\;mg/\;{\ell}$ of NAA.

• Korean Journal of Plant Tissue Culture
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• v.22 no.2
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• pp.89-93
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• 1995

Regeneration and growth of bulblets from bulblet-derived bulb-scale segment of Lilium longiflorum (cv Georgia) were investigated. Bulblets were initiated on bulb scales taken from bulblets on MS medium containing 0.05 mg/L 2,4D with 3% sucrose or 0.02 mg/L 2,4D with 9% sucrose. Benzyladenine promoted the differentiation of bulblets but inhibited the growth of differentiating bulblets. The growth of bulblet was promoted by supplying 1/2 strength 1/2 NH$_4$NO$_3$ concentration in MS medium containing 12% sucrose.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.20
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• pp.1-26
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• 1975

In order to provide basic information for the application of tissue culture to a rice breeding program. experiments were carried out on the callus formation from seedings and anthers and organ differentiation from the callus of rice varieties and their hybrids. It appeared that in general the callus tissue was more easily induced in japonicas than in indicas with significant varietal differences. A highly significant positive correlation (r=0.896$^{**}$) was obtained between the fresh weight of callus induced in NAA medium and in 2, 4-D medium in the same variety. Callus formed on the medium with 2, 4-D was more friable than that formed on the medium with NAA. The callus formation from seedlings was better than from anthers in upland rice varieties. The easiness of the callus formation appeared to be a dominant character in crosses of rice varieties. Varietal difference was also noticed in the organ differentiation from the callus and the root differentiation seemed to be easier than the shoot differentiation. Most of the plants derived from the cal1us were albinos and the frequency of occurrence of albinos was greater in callus of seedlings than in that of anthers. Greater amount of callus tissue was formed from anthers of $F_1$ plants than anyone of their parents in remote-crosses but it was clear in close-crosses. A highly significant positive correlation (r=0.504$^{**}$) was found between the callus formation from seedlings and from anthers.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03a
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• pp.199-210
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• 2004

제주도는 신생대 제 3기~4기에 형성된 화산섬으로서 수십 차례에 걸친 화산분출에 의해 형성되어 지리적으로 한반도의 최남단에 위치하고 있으며, 우리나라에서 가장 큰 섬이다. 섬 중앙의 한라산을 중심으로 쉴드 화산체를 이루고 있는 제주도는 동서의 길이가 약 74km, 남북의 길이가 약 34km되며 섬 전체 면적이 1,825$\textrm{km}^2$인 타원형의 모양을 하고 있다. 제주도의 중앙부에는 수 차례의 화산활동에 의해 형성된 약 1,950m 높이의 한라산 정상에는 지름이 약 575$\times$400m, 깊이가 100m에 이르는 분화구가 있으며, 돔상의 조면암이 분화구 주변에 관입 되어 있다.(중략)

• The Korean Journal of Zoology
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• v.37 no.4
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• pp.514-523
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• 1994

꼬리명주나비(서ericinus montela) 조혈기관의 분포 및 미세구조를 광학현미경과 투과전자현미경을 이용하여 관찰하였다. 꼬리명주나비의 조혈기관은 흉부 제 2 · 3체절의 날개발생부위(imaginal wing disc)에 부착되었거나 인접해 있었다 각각의 조혈기관은 비세포성 기저 막으로 둘러싸인 여러 개의 조혈섬으로 구성되어 있었으며, 조혈 섬들은 compact islet(치밀하게 배열된 조혈섬)과 loose islet(느슨하게 배열된 조혈섬)으로 구분되었다. 혈구의 분화는 loose islet 내에서 진행되었으며, 시원세포로부터 원시혈구. 부정형혈구, 과립혈구, 소구혈구가 독자적 경로를 통해 분화되었다.

• The Bimonthly Magazine for Agrochemicals and Plant Protection
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• v.11 no.6 s.99
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• pp.41-48
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• 1990

생장조정제 사용에 앞서 작물재배과정에서 꼭 알아둘 점이 있다면 (1) 생장조정제는 재배환경에 민감하게 작용하기 때문에 온도, 습도, 광등을 고려하여 정상생육 환경이 되도록 재배환경을 잘 맞춰줘야 약제발현 효과가 있으며 (2) 토양환경면에서 세포생리 기능이 정상적으로 분화발육 할 수 있을 때 약제 발현성을 높이기 때문에 비배관리면에 특히 유념해야 한다는 것이다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.271-276
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• 1985

Effects of media and its components on callus induction and plant regeneration were studied to increase the cultural efficiency in rice anther culture. The N$_{6}$ basic medium gave better results in callus induction than those of MS or Miller. The medium used for callus induction affects the plant regeneration. The frequency of plant regeneration from callus grown on Miller basic medium was lower than those of N$_{6}$ or MS. Most of calli derived from anthers, above 90%, were induced from 20 days to 40 days after anther inoculation. The cultural efficiency of modified N$_{6}$ basic medium which was composed of 31.5mM KNO$_3$ and 1.75mM(NH$_4$)$_2$SO$_4$ as nitrogen sources was higher than those of N$_{6}$ basic medium. Combination of NAA and Kinetin showed better results than that of 2, 4-D only in cultural efficiency. Effect of DL-alanine on callus induction in Indica variety, IR40, showed better response in the anthers pretreated for 6 days at 12$^{\circ}C$.

• The Korean Journal of Zoology
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• v.32 no.2
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• pp.163-175
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• 1989

Transferrin (Tf) has been known to exert profound effect on the myoblast differentiation in uirto. Therefore, the changes in the amount and affinity of the Tf receptor would accompany the myoblast differentiation. To investigate this possibility, we exarnined the afteration pattern in the level of the Tf receptor during the myoblast fusion. The level of Tf receptor was assayed by measuring the bound 125 I-Tf onto the surface of cultured myoblasts, and it was known that the level of Tf receptor reached the maximum at about 12 hr before the initi ation of the myoblast fusion and decreased as the differentiation proceeded, and that the affinity of Tf receptor to Tf was also decreased. In addition, various inhibitiors of the myoblast fusion also influenced the level of the Tf receptor. Accroding to these results, it is postulated that the level of Tf receptor is highly regulated during the myoblast differentiation.