• The korean journal of orthodontics
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• v.10 no.1
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• pp.7-13
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• 1980

To study some informations on the morphogenesis and developmental process of the coronal suture in rats, the author performed daily oral administrations of demethylchlorotetracycline, a kind of tetracycline group, in the amount of 30mg/kg of body weight to the female rats from the 7th day of pregnancy to the time of delivery. Microscopic evaluation was undertaken on the fetal rats in the experimental group. The subject of this experiment were defined to the fetal rats of each group at 1st, 3rd, 7th and 14th day after birth. All these fetal rats were sacrificed and the heads were removed. All the tissue sections were fixed with $10\%$ formalin, Bouin' and Carnoy' solution and then stained by Hematoxylin-Van Gieson stain, or Feulgen and Rossenbeck, Periodic acid Schiff, and prepared for alcian blue reaction. The results were as follows; 1. The directions of osteogenic fibers were arranged irregulary during first 3 days, but after the 7th day they tended to change radial directions like control group. 2. The density of deep stained cells by Feulgen-Rossenbeck reaction were shown leu in the experimental group than that in the control group in first 3 days, but there was shown no significant difference between both groups after the 7th day. 3. PAS reaction in early stage was generally negative in the experimental group unlike as in the control group, but diffuse reaction was observed in the loose middle zone like as in the control group after 14th day. 4. Alcian blue reaction was negative in cambial zone, and slightly positive in uniting zone compared with control group in early stage. After 14th day, however, there was observed a tendency of moderately positive reaction.

• The Korean Journal of Quaternary Research
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• v.13 no.1
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• pp.25-33
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• 1999

The relationships between climate (monthly precipitation and temperatures) and tree-ring growth of Korean fir (Abies koreana) growing at subalpine (1,600∼l,700m) zone on the south slope, Joong-Bong and the north slope, Changgun-Bong in the Cheonwang-bong area in Chiri mountains in the southern Korea were analyzed. Two cores from each of 10∼12 trees were extracted. The relationship between tree-ring(standardized) chronologies and climate was analyzed by the response-function method. Climate variables could explain 45.9∼53.8% of total variance in the chronologies. The precipitation response function of Korean fir were similar at both sites in overall ; positive for March∼May and August, and negative for February and July. The south-slope fir of Joong-Bong possessed higher negative temperature response function for February and August than north-slope one. The positive response function for April temperature was significant for both sites. In contrary to other subalpine species (e.g., Pinus koraiensis and Taxus cuspidata) in South Korea, whose growths are positively correlated with temperature in most seasons, the growths of Korean fir trees in Mt. Chiri appeared to be mainly limited by the moisture regime of spring prior to the cambial growth and early growing season.