• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.431-437
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• 2023

This study evaluated the ecological characteristics related to spike heading time of three Korean foxtail millet cultivars, i.e., one early and two late maturities, and a finger millet cultivar in the north-central region of the Korean Peninsula, Kangwon Province. The changes in heading time occurred due to the changes in planting time from mid-May to late June. The heading time of the early-maturity cultivars was early August, with 80 days required for heading (DH) for the mid-May planting; late August, with 65 DHs for the late June planting; and mid-late August, with 100 DHs and mid-October, with 65 DHs, respectively, for the late-maturity cultivars. The accumulated temperature at heading time ranged from 1,700℃ of mid-May planting to 1,500℃ of late June planting in the early-maturity cultivars. In contrast, it ranged from 2,100℃ to 1,900℃ in the late-maturity cultivars. The photoperiod at heading time ranged from 14.0 h to 13.2 h in the early-maturity cultivars, whereas it was from 13.2 h to 12.5 h in the late-maturity cultivars. Considering that the limiting heading time of Korean foxtail millet and finger millet in the northern region of Kangwon Povince is late August, the limiting accumulated temperature at the heading time was evaluated to be approximately 1,500℃ and 2,000℃ for early and late-maturity cultivars, respectively. The mean daily temperature from planting to heading time showed a negative correlation with the DH, which was shortened with the increase in mean daily temperature. This suggests that delaying the planting time from May to June in the north-central region of the Korean Peninsula increases the mean daily temperature during vegetative growth periods, resulting in the decrease of the DH and the accumulated temperature.

• Radiation Oncology Journal
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• v.19 no.1
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• pp.45-52
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• 2001

Purpose : Granulocyle-colony stimulating factor (G-CSF) has been widely used to treat neutropenia caused by chemotherapy or radiotherapy. The efficacy of recombinant human hematopoietic growth factors in improving oral mucositis after chemotherapy or radiotherapy has been recently demonstrated in some clinical studies. This study was designed to determine whether G-CSF can modify the radiation injury of the intestinal mucosa in mice. Materials and Methods : One hundred and five BALB/c mice weighing 20 grams were divided into nine subgroups including G-CSF alone group $(I:10\;{\mu}g/kg\;or\;II:100\;{\mu}g/kg)$, radiation alone group (7.5 or 12 Gy on the whole body), combination group with G-CSF and radiation (G-CSF I or II plus 7.5 Gy, G-CSF I or II plus 12 Gy), and control group. Radiation was administered with a 6 MV linear accelerator (Mevatron Siemens) with a dose rate of 3 Gy/min on day 0. G-CSF was injected subcutaneously for 3 days, once a day, from day -2 to day 0. Each group was sacrificed on the day 1, day 3, and day 7. The mucosal changes of jejunum were evaluated microscopically by crypt count per circumference, villi length, and histologic damage grading. Results : In both G-CSF I and II groups, crypt counts, villi length, and histologic damage scores were not significantly different from those of the control one (p>0.05). The 7.5 Gy and 12 Gy radiation alone groups showed significantly lower crypt counts and higher histologic damage scores compared with those of control one (p<0.05). The groups exposed to 7.5 Gy radiation plus G-CSF I or II showed significantly higher crypt counts and lower histologic damage scores on the day 3, and lower histologic damage scores on the day 7 compared with those of the 7.5 Gy radiation alone one (p<0.05). The 12 Gy radiation plus G-CSF I or II group did not show significant difference in crypt counts and histologic damage scores compared with those of the 12 Gy radiation alone one (p>0,05). Most of the mice in 12 Gy radiation with or without G-CSF group showed intestinal death within 5 days. Conclusion : These results suggest that G-CSF may protect the jejunal mucosa from the acute radiation damage following within the tolerable ranges of whole body irradiation in mice.