• Korean Journal of Poultry Science
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• v.36 no.4
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• pp.293-300
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• 2009

The rate of fetus with abnormal chromosomes increase with maternal age. Nondisjunction of aging oocyte chromosome is a major reason for the increased rate of abnormalities. Telomeres are the ends of eukaryotic chromosome, which are essential for chromosome stability and are related in cell senescence. This study was carried out to analyze the chromosome aberration rate and amount of telomeric DNA in chick embryo along with maternal age. Fertilized eggs and blood were sampled from White Leghorn layers starting at 20 weeks through to 70 weeks age at 10 weeks interval. Chromosome aberration rate was analyzed by karyotyping. The amounts of telomeric DNA in embryonic cells and lymphocytes were quantified by Quantitative Fluorescence in situ Hybridization method. The chromosome aberration rate in chick embryos significantly differed with maternal age. The chromosome aberration rate increased at early laying period and beyond 70 weeks of maternal age. Therefore, chromosome aberration rate was affected by maternal age due to ovulated oocytes state. However, the amount of telomeric DNA on embryonic cells did not differ significantly with maternal age. Thus, maternal age does not affects telomere quantity in their embryos due to cellular reprograming at early embryonic stage after fertilization.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2002.04a
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• pp.69-75
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• 2002

Sterols play two major roles in plants: a bulk component in biological membranes and precursors of plant steroid hormones. Physiological effects of plant steroids, brassinosteroids (BRs), include cell elongation, cell division, stress tolerance, and senescence acceleration. Arabidopsis mutants that carry genetic defects in BR biosynthesis or its signaling display characteristic phenotypes, such as short robust inflorescences, dark-green round leaves, and sterility. Currently there are more than 100 dwarf mutants representing 7 genetic loci in Arabidopsis. Mutants of 6 loci, dwf1/dim1/cbb1, cpd/dwf3, dwf4, dwf5, det2/dwf6, dwf7 are rescued by exogenous application of BRs, whereas bri1/dwf2 shares phenotypes with the above 6 loci but are resistant to BRs. These suggest that the 6 loci are defective in BR biosynthesis, and the one locus is in BR signaling. Biochemical analyses, such as intermediate feeding tests, examining the levels of endogenous BR, and molecular cloning of the genes revealed that dwf7, dwf5, and dwf1 are defective in the three consecutive steps of sterol biosynthesis, from episterol to campesterol via 5-dehydroepisterol. Similarly, det2/dwf6, dwf4, and cpd/dwf3 were shown to be blocked in $D^4$ reduction, 22a-hydroxylation, and 23 a-hydroxylation, respectively. A signaling mutant bri1/dwf2 carries mutations in a Leucine-rich repeat receptor kinase. Interestingly, the bri1 mutant was shown to accumulate significant amount of BRs, suggesting that signaling and biosynthesis are dynamically coupled in Arabidopsis. Thus It is likely that transgenic plants over-expressing the rate-limiting step enzyme DWF4 as well as blocking its use by BRI1 could dramatically increase the biosynthetic yield of BRs. When applied industrially, BRs will boost new sector of plant biotechnology because of its potential use as a precursor of human steroid hormones, a novel lead compound for cholesterol-lowering effects, and a various application in plant protection.

• Korean Journal of Organic Agriculture
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• v.11 no.3
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• pp.75-90
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• 2003

A total of 192 Korean landraces were investigated for the comparison of each other as useful germplasm to organic farming and examined correlation between quantitative traits. Almost Korean landraces were classified into medium-heading variety and average days from seeding to heading was 111.1 days. Plant height and culm length were longer about 20∼40cm than general Japonica cultivar. Average width of leaf blade and average length of panicle were 1.3cm and 22.4cm, respectively, Average number of panicles per plant was 10.0 and almost varieties showed low tilling habit. Average length/width ratio of brown rice was 1.7 and several varieties were long grain type and average 1,000 grain weight was 21.6g. In correlation coefficient among quantitative traits, positive significant correlations were observed between culm length and leaf width, days from seeding to heading, but negative correlations were observed between days from seeding to heading and 1000 grain weight. 27.1% of Korean landraces showed weak and lodging degree in culm strength and 3.6% of total varieties showed purple margin on leaf blade and leaf sheath. In leaf blade angle and flag leaf angle, erect type was 46.9% and 10.9%, respectively. 24.0% of total varieties showed the slow and late degree of leaf senescence. The rate of awned type, waxy type and brown seed coat were 74.5%, 20.3% and 4.2%, respectively. The color of stigma, spikelet, apiculus and awn showed diverse color such as white, brown, red and purple.

• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.537-542
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• 2004

To reveal the relationship between the changes in the growth and photo- synthesis induced by low dose radiation, red pepper (Capsicum annuum L.) plants were serially irradiated three times with gamma rays of 0.5, 1, 2, 3, and 4 Gy. The plant growth was monitored by the fresh weight, the stem length, and the leaf length & width. All the irradiation groups (0.5-4 Gy) were stimulated in growth at 1 day after the $1^{st}$ irradiation (DA1I), but rather inhibited at 3 days after the $3^{rd}$ irradiation (DA3I). The maximum photochemical efficiency (Fv/Fm), the photochemical quenching (qP), the non-:photochemical quenching (NPQ) and the apparent rate of the photosynthetic electron transport (ETR) were used to represent the changes in the photosynthesis by the serial irradiation. The irradiation groups except 0.5 Gy had higher Fv/Fm values at 3 DA3I than the control one. After the 3$^{rd}$ irradiation, the qP values appeared to be a little lower in the 1-4 Gy groups than in the control and 0.5 Gy ones. In contrast, the NPQ values were rather higher in the irradiation groups except 0.5 Gy. During the whole experimental period, the ETRs decreased in the control group but remained relatively constant in the 4-Gy one. In conclusion, the results obtained indicate that the stimulatory effect of ionizing radiation on the plant growth was determined by the incident dose of the single irradiation rather than by the cumulative one of the serial irradiation. They also demonstrate that the growth stimulation induced by a low dose radiation could not be positively correlated with an alteration in the photosynthesis. Additionally, we discuss in text that an ionizing radiation may partly protect the leaf senescence by delaying the development of the plants.

• Korean Journal of Soil Science and Fertilizer
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• v.5 no.1
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• pp.9-15
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• 1972

Comparative analyses of canopy structure were conducted using newly bred high yield rice cultivars (IR 667-Suwon 213 and 214) and commercial varieties (Jinhung and Paldal) under the field condition. "Canopy score" as criteria of canopy structure was proposed. The results were summerized as follows: 1. IR667 line (IR8${\times}$Taichung Native 1${\times}$Yukara) showed lower canopy height, greater tiller openness, smaller leaf openness and leaf length ratio (flag leaf/3rd), shorter 4th and 5th internode length, greater diameter of 5th internode, consequently greater leaf area index, panicle weight and leaf weight ratio (leaf/leaf sheathculm) as merits, and greater leaf width, smaller leaf number(number of leaf/$m^2$)and specific leaf area($cm^2/g$) and faster destruction of canopy by senescence as demerits comparing with commercial varieties. 2. IR 667 line showed much higher "Canopy score", subsequently higher yield. 3. The quality of individual leaf was better in the commercial varieties indicating that the best combination for the better yield would be the leaf of commercial varieties with the structure of IR667 line.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.502-509
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• 1993

In Ulrung floral community the growing environments and nutritive values of wild garlic was investigated. The wild garlic, grown for $3{\sim}4\;years$ in community area, were able to develope bulbs. The bulbs with 2 leaves had the highest ratio of propotion as 75.1% of share among the distribution of bulbs with completely developed leaves and 1 leaf-bulbs and 3 leaves-bulbs had 19.6% and 5.3%, respectively. Also the 2 or 3 leaves-bulbs indicated the better growth states in the part of shoot and bulbs than 1 leaf-bulbs, and there was a significant defferences in each growth between 2 leaves-and 3 leaves-bulbs. On the wild garlics we cannot find out insect injuries. However, there was deseases with symptoms of leaf-spots and lesion from May to June. At first it made a small spots on the leaves, followed by senescence at arrounding area of spots, and then it expanded to whole leaf. This pathogenic bacterium was supposed to be a member of Aristastoma. The contents of crude protein, fat, and carbohydrate in each portion of wild garlics decresed in the order of shoot, expanded leaves and bulbs. On the contrary, crude fibers increased in the same order and so it is not suitable for human consumption nutritional value. However, because the shoots of wild garlics have more than the other Allium sp., the shoots will be a good quality food stuff.

• Journal of Food Hygiene and Safety
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• v.32 no.3
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• pp.243-248
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• 2017

Intracellular and extracellular oxidative stress initiated by reactive oxygen species (ROS) causes skin aging, which is characterized by wrinkles and atypical pigmentation. Use of antioxidant is an effective approach to prevent symptoms related to ROS-induced aging of the skin. Therefore, the antioxidant and anti-aging effect of Castanea crenata Siebold & Zucc. extracts (LCE) was investigated in this study. The LCE markedly reduced the hydrogen peroxide-induced cell damage, intracellular ROS, and oxidative stress-induced senescence in human dermal fibroblasts (HDFs). These results indicate that LCE might have beneficial effects on oxidative stress-induced damage and thus reduce skin aging.

• Applied Biological Chemistry
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• v.51 no.4
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• pp.288-293
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• 2008

This study was to evaluate the protective effect of vitamin E against long and short-term stress in ICR mice. Two groups which had been bred for 5 months (equivalent to human beings aged 20) were treated by immobilization stress for 8 weeks with or without vitamin E, and one out of two groups was continuously bred until they become 18 months old (equivalent to human senescence) with or without Vitamin E. Afterwards, the changes of serum and hepatic metabolites were investigated on the basis of the index of stress-related in vivo oxidative damage. As a result, it was found that stress increases serum triacylglycerol and aspartate aminotransferase (AST) in the long and short-term, and decreases serum HDL-cholesterol. In addition, stress concerned the decrease of total antioxidant status (TAS) and superoxide dismutase (SOD) as well as the increase of malondialdehyde (MDA) in liver. These results suggest that stress in one’s youth causes negative results in TG, HDL-cholesterol, AST, TAS, SOD and MDA measured in one’s senescent. The administration of vitamin E in the stressed mice decreases serum TG and AST that are increased by stress, and exerts influence on the increase of serum HDL-cholesterol. Also vitamin E recovered the values of liver TAS, SOD and MDA in the stressed mice. In conclusion, vitamin E represented protective effect in the stressed mice to some degree.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.92-98
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• 1985

The experiments were conducted to investigate the activity changes of peroxidase, existence of isoenzyme and the changes of reserved substances in tomato under subatmospheric pressure storage condition. The results obtained were as follows: 1. Soluble fraction showed the highest peroxidase activity and followed by cell wall fraction, mitochondria fraction and ribosome fraction in that order. 2. Peroxidase activity was decreased during the ripening and senescence period in tomato. Especially, peroxidase activity in tomato was higher at a room temperature ($25^{\circ}C$) than at a low temperature ($15^{\circ}C$). The decreasing inclination was similar in both treatment. The peroxidase activity was higher in 380 Torr, than in 570 Torr. 3. At least, two isoperoxidases(Soluble or solubilized) were identified from different extraction procedures. Three of four isoenzymes were recognized from a vertical slab of polyacrylamide gel electrophoresis. 4. The changes of components in tomato under SAP were generally affected by temperature and pressure. Especially, quality of tomato stored at a low temperature ($15^{\circ}C$) and SAP (380 Torr.) was best during storage.

• Women's Health Nursing
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• v.5 no.2
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• pp.204-221
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• 1999

Due to the ever increasing life-span of human beings, the average woman is living well into her 70's. Henceforth, they spend at least one-third of their life after menopause. Climacteric encompasses the time preceding, during, and proceeding menopause : a transitional period of shifting from the period of being fertile to the period of senescence. In other words, this is the time at which they lose the ability to reproduce. Menopause can influence a woman's sexual life immensely due to the physiological, social, and psychological changes that occur during that period. In korea, where some women still live according to Confucian Culture in terms of sexology, nurses can play a vital role in the dissemination of sexual facts to women. This study was designed to clarity the characteristic and satisfaction of sexual life. This was done according to the classification of three types of climacteric women : pre-meno-pausal, menopausal, and post-menopausal. I studied 159 climacteric women between the ages of 45 & 59, living in or around the vicinity of Taegu City. This study utilized the investigative tools for sexual life patterns which were constructed with field experts' consultation and reference review by the author. The sexual satisfaction was translated from DSFI. The climacteric symptoms were invented by Kupperman, This research is descriptive. The data was collected between July 15, 1998 and October 14, 1998. Statistical analysis was performed using ANOVA and Pearson Correlations, and was computed with the SPSS program. The results obtained are summarized as follows; The frequency of sexual activity was highest in pre-menopause and declined after menopause. The frequency of genital caressing declined after menopause. The difference between the frequency of masturbation and coital pain was not significant according to the classification set forth in this experiment. Congruently, the frequency of orgasms declined after menopause. The mean satisfaction of sexual life is 27.1 years. The range of expected score is 9-45 years of age. Satisfaction was highest in the pre-menopausal group and proved to be statistically significant. Some of the general characteristics that affected the satisfaction a woman's sexual life in the climacteric stage during this project were ; age, income, satisfaction in younger pre-menopausal and the large income group than the other experimental groups. The climacteric symptoms were conversely correlated with the satisfaction in one's sexual life.