• Horticultural Science & Technology
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• v.30 no.4
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• pp.385-391
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• 2012

The growth of terminal shoots of persimmon (Diospyros kaki) was analyzed during the first two months from the time of bud sprout to understand the dynamics of their early growth. Field-grown, mature 'Fuyu' and 'Nishimurawase' trees were used in a three-year study at two locations in Gyeongnam province. The growth of terminal shoots was most active from late April, about 10 days after foliation, to early May, followed by a gradual decline by late May. The increase in leaf area continued unabated throughout May. The weight of a flower bud increased slowly until early May and rapidly after flowering. Although its extension growth had been ceased by late May, dry weight (DW) of a terminal shoot continued to increase almost linearly throughout May due to shoot thickening and continued growth of leaves and fruits. In late May, the leaves and the stem accounted for more than 60% and less than 20% of total DW of a shoot respectively; fruit proportion increased to 7 to 17% by then. Relative growth rate (RGR) of the terminal shoot was higher than 213 $mg{\cdot}g^{-1}{\cdot}d^{-1}$ in late April, but declined to less than 63 $mg{\cdot}g^{-1}{\cdot}d^{-1}$ in late May. Like the pattern of seasonal changes in RGR, net assimilation rate (NAR) of the shoots decreased from 1.9 to 2 $mg{\cdot}cm^{-2}{\cdot}d^{-1}$ to 0.5 to 0.8 $mg{\cdot}cm^{-2}{\cdot}d^{-1}$. An early-season 'Nishimurawase' did not differ from a late-season 'Fuyu' in RGR and NAR during the first two months of growth. The early growth of the shoots was affected mainly by the reserves redistributed from permanent organs, however, environmental conditions at the time was also involved.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.1
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• pp.53-57
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• 2013

A severe defoliation by typhoon in early autumn reduces fruit quality for the current season and reserve accumulations for the next season. This study was conducted to determine the effects of foliar applications during the autumn on alleviating the damages after defoliation. Leaves of 2-year-old 'Fuyu' trees, grown in 50-L pots under a rain-shelter, were 75%-defoliated on September 9. In mid-September and early October, trees were treated either with eight foliar applications of urea or with four alternating applications of urea and $KH_2PO_4$ (urea + KP application), all at 0.5% (w/v). Trees untreated after the defoliation served as the control. The urea applications slightly increased N and P concentrations of the leaves collected on November 6, while urea + KP applications significantly increased P and K concentrations. Foliar applications did not affect fruit growth, but tended to decrease skin coloration. Fruit soluble solids increased by 1.5 and $1.0^{\circ}Brix$ for urea and urea + KP applications, respectively. There was a significant increase in dry weight of fine root for the foliar application treatments but not in those of aerial woods and larger roots. With the foliar applications, N concentration tended to increase in the permanent organs but not P and K, whereas soluble sugars and starch notably increased in shoot, trunk, or fine root regardless of the different applications. Results indicated that the foliar applications could partially help to restore fruit quality and carbohydrate accumulations in the defoliated trees.

• Korean Journal of Agricultural Science
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• v.19 no.1
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• pp.51-64
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• 1992

This experiment was carried out to elucidate the effects of the thyroid function on lactation in female rats. One hundred and five female rats, whose body weight was approximately 250g with normal parturition, were divided into 3.5 THY, 35 PTU, and 35 CON. The $30{\mu}g$ L-thyroxine per rat was administered subcutaneously for the THY group with 3-days intervals arid 0.03% propylthiouracil solution was drunk for the PTU group. After the treatments body weight, thyroid weights and prolactin levels in serum, and histological changes in thyroid and mammary gland were investigated for 3 weeks with 3-days interval. The results obtained were as follows 1. The body weights of PTU group were lower than those of CON arid THY groups. The changes in body weights were significant between 3 and 6 days and between 15 and 18 days. 2. Differences in thyroid weight among the groups were significant after 9 days, The thyroid weights of PTU group were much higher than those of CON and THY group. 3. The follicular epithelia of PTU group after 6 days showed cuboidal phenomena which were accompanied by hypertrophy and hyperplasia, and this phenomena continued until post weaning period. Those of THY group after 9 days showed a squamous degeneration together with pyknosis. 4. The prolactin concentrations of THY group were higher than the other groups after 12 days. and those of CON group were higher than the others after 18 days. However, those of PTU group were lower all through the period. 5. The secretary epithelial cells of THY and CON groups became cuboidal after 12 days, but after 15 days the differentiation of mammary tissue was progressing in THY group faster than CON group. The degeneration of mammary tissue were observed in PTU group as time lapses, so after 15 days the exfoliation of secretory epithelium and atrophy of alveolus were recognized. 6. The body weights of offspring for all experimental groups were increasing as time lapses, but the values for PTU group were markedly lower than the others.

• Clinical and Experimental Pediatrics
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• v.45 no.6
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• pp.773-782
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• 2002

Purpose : To identify the necessity of more reasonable diagnostic criteria and the possibility of early prediction of coronary involvement in the higher risk group, we investigated and compared clinical and laboratory findings in the acute phase and coronary involvements in those younger (n=17) and older(n=53) than one year of age in Kawasaki disease(KD). Methods : Retrospective chart reviews were performed on 70 patients with KD who were admitted to the Chung-Ang University Hospital from April 1997 to May 2001. Results : Male were significantly higher in the younger age group(M : F ratio 3.3 : 1 vs. 1.0 : 1, P=0.004). Fever durations before intravenous immunoglobulin(IVIG) and echocardiography were significantly shorter in the younger group($4.6{\pm}1.3$ vs. $6.2{\pm}2.5$, P=0.004 vs. 0.01, respectively). Cases meeting typical diagnostic criteria were significantly less in the younger group(P=0.006). In the laboratory findings, serum albumin, BUN and $K^+$ levels in the acute febrile phase were significantly higher in the younger group(P=0.002, 0.006, <0.001, respectively) and incidences of coronary artery dilatation in the acute phase were significantly higher in the younger group(P=0.01). Conclusion : Although less met the typical diagnostic criteria of KD, infants younger than one year of age are more susceptible to coronary artery change in the acute febrile phase. Therefore, KD should be entertained as a diagnostic possibility in young infants with prolonged fever without distinct fever focus, and echocardiography should be considered as part of the evaluation of these patients, and then early diagnosis and prompt IVIG should be conducted.