• Korean Journal of Agricultural Science
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• v.39 no.1
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• pp.69-73
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• 2012

The purpose of this study was to evaluate the potential of naturally occurring aldose reductase (AR) inhibitors from white-color natural products (Aruncus dioicus var. kamtschaticus, Chionanthus retusa, Cosmos bipinnatus, Hibiscus syriacus, Hydrangea paniculata, Magnolia denudata, Prunus padus, Robinia pseudo-accacia, Rhododendron mucronulatum for. albiflorum, Spiraea blumei, and Spiraea prunifolia var. simpliciflora). The MeOH extract of white-color natural products were tested on rat lens AR inhibition in vitro. Among them, the MeOH extract of R. mucronulatum for. albiflorum showed highest inhibition on AR ($IC_{50}$ value, 1.07 ${\mu}g/ml$). These results suggested that R. mucronulatum for. albiflorum, a white-color natural product, could be a useful resource in the development of a novel AR inhibitory agent against diabetic complications.

• The Korean Journal of Ecology
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• v.8 no.1
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• pp.53-59
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• 1985

Phenological development, flowering and leafin times of Rhododendron muronulatum and R. schlippenbachii along elevagtion were studied at Mt. Kwanak, 629m high above the sea level, in Seoul. Flowering and leafing time of the former were delayed at the rate of 2.3~3.3 days and those of the latter were of 2.0~3.0 days per 100m ascent. Phenological changes of both plant species were closely correlated with minimum air temperature first, and then soil water content and minimum soil temperature among the climatic factors. Phenological difference caused by altitude and slope direction(southeast-northwest) among the topographic factors was admitted at the high significance level, but the difference by ridgevalley was little.

• Journal of Plant Biology
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• v.26 no.1
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• pp.33-39
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• 1983

Twigs bearing floral buds of Rhododendron yedoense var. poukhanense(Ryp) and R. sinmsii(Rs), hardy species in Korea, were used to investigate the cold hardiness in relation to the developmental and anatomical characteristics, and the changes of water content. In floral buds of both species, the reproductive organs, pistils and stamens, matured within the bud scales in early ctober to prepare for a cold acclimation. The ray parenchymatous areas occupied in xylem were 41% in Ryp and 38% Rs. As the storage temperature is raised from 2 to 17$^{\circ}C$, water content increased more highly in Rs than in Ryp. Exotherm temperature of floral bud in Ryp was generally lower than that in Rs. The result supports that the higher cold-hardiness is achieved owing to the earlier maturation of floral buds, to the larger area of ray parenchyma in xylem, and to the lesser increase of water content as the storage temperature is raised.

• Journal of Environmental Science International
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• v.20 no.4
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• pp.427-434
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• 2011

This study characterized the full range of vegetation in a upland wetland (marshland) in Korea. Classified community types were used to describe vegetation at the marshland and adjacent areas. The communities contained 44 species of vascular plants and all species were identified into four plant community types. The Rhododendron yedoense f. poukhanense type and Lespedeza cyrtobotrya type had a high representation infacultative upland species (FU) and obligate upland species (OU), respectively. The monocot type was dominant in marshland by Miscanthuns saccharifloruc and contained 14 species. Together the three areas contained four species, with the strongest indicator species being Ranunculus acris var. nipponicus, Rhododendron yedoense f. poukhanense, Hemerocallis fulva, and Miscanthuns sinensis var. purpurascens. Shannon-Weaver index of diversity also varied among the community types (F = 18.9, df = 2), with the types FU having significantly higher value (3.467) than the others (1.125 for type FW and 1.239 for type OU).

• Journal of The Korean Society of Clinical Toxicology
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• v.3 no.1
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• pp.52-55
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• 2005

The plant Korean rosebay are members of the Ericaceae(Heath) family and may contain grayanotoxins, which exert toxic effects by binding to sodium channels in cell membranes. We had experience of 2 cases of Korean rose bay intoxication, who exposed to Rhododendron mucronulatum. Patients were presented to our ED with nausea and vomiting, hypotension, and dizziness or depressed mentation. The patients were performed monitoring and supportive treatment and were fully recovered within 48hours. Korean rose bay intoxication should be considered in patients with clinical evidence of gastrointestinal irritation, cardiac arrhythmias, and/or neurologic signs without identifiable causes, especially in spring or early summer.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.4
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• pp.363-370
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• 1989

Nutritional value of azalea pollen and its effect on the carbontetrachloride induced liver damage were investigated in this experiment. Azalea pollen was primary composed of 58.96% of carbohydrate, 21.86% crude protein, 2.26% fat, and 2.89% ash. 17 amino acids and 22 fatty acids were quantitatively analyzed, and the major component of them was lysine, and linolenic acid, respectively. After administration of pollen and carbontetrachloride concomitantly. serum ALT, AST, LDH activities and tissue lipid peroxidation decreased significantly, but serum total lipid and cholesterol levels did not changed.

• Korean Journal of Pharmacognosy
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• v.26 no.2
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• pp.168-174
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• 1995

Korean folk medicine 'Man Byung Cho' has been used to cure abdominal pain, athlete's foot and neuralgia. The botanical origin of the crude drug has never been studied pharmacognostically. To clarify the botanical origin of 'Man Byung Cho', the leaf morphology and anatomy were examined for the Korean species of Rhododendron subgenus Hymenanthes, such as R. brachycarpum G. Don, R. brachycarpum var. rosueum Koidz. and R. aureum Georgi. The study shows that 'Man Byung Cho' is the leaf of R. brachycarpum and R. brachycarpum var. roseum.

• The Korean Journal of Ecology
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• v.11 no.3
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• pp.109-122
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• 1988

The foret vegetations of Daedunsan provincial park area in Korea were classified into eight communities of Acer mono-Zelkova serrata, Lindera erythrocarpa-Cornus controversa, Carpinus tschonoskii, Quercus variabilis, Quercus serrata, Carpinus laxiflora, Rhododendron schlippenbachii-Quercus mongolica and Rhododendron mucronu-latum-Pinus densiflora by the Z-M method. By two dimensional analysis of temperature, moisture gradients, the eight communities were grouped into four vegetation types: cove forest dominated with Zelkova serrata and Cornus controversa, hornbeam forest with Carpinus tschonoskii and Carpinus laxiflora, oak forest with Quercus variabilis, Quercus mongolica, Carpinus laxiflora, Carpinus tschonoskii, Zelkova serrta and Pinus densiflora community was made from the analysis of actual vegetation map by the phytosociological classification, environmental conditions and human interferences.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.3 s.39
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• pp.137-141
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• 1990

This study was carried out to investigate the propagation methods of the Rhododendron micranthum as a landscape plant The results obtained are as follows :　1. The optimum temperature for seed germination was $20^{\circ}C$, and the seed germination needs light. 2. GA and thiourea did not affect the seed germination under light, but GA gad substitutive effect. 3. 87% and over of germination rates were obtained in room temperature and $5^{\circ}C$ dry storages. 4. The rooting rate was high on sandy loam, vermiculite, and vermiculite 50%+sand 50%, at softwood and hardwood cutting(hardwood ; 45~48%, softwood ; 45~48%). 5. The significant effects on rooting were found with the treatment of NAA 500~2000ppm.

• Journal of Plant Biology
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• v.29 no.1
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• pp.53-65
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• 1986

The montane forests of Ulreung Island, Korea, were investigated by the ZM school method. By comparing the montane forests of this island with those of Korean Peninsula and of Japan, a new order, F a g e t a l i a m u l t i n e r v i s, a new alliance, F a l g i o n m u l t i n e r v i s, a new association, H e p a t i c o-F a g e t u m m u l t i n e r v i s and Rhododendron brachycarpum-Pinus parviflora community were recognized. The H e p a t i c o - F a g e t u m m u l t i n e r v i s was further subdivided into four subassociations; Subass. of Sasa kurilensis, Subass. of Rumohra standishii, Subass. of Rhododendron brachycarpum and Subass. of typicum. Each community was described in terms of floristic, structural and environmental features.