• Development and Reproduction
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• v.17 no.4
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• pp.469-475
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• 2013

In mammals, puberty is a process of acquiring reproductive competence, triggering by activation of hypothalamic kisspeptin (KiSS)-gonadotropin releasing hormone (GnRH) neuronal circuit. During peripubertal period, not only the external genitalia but the internal reproductive organs have to be matured in response to the hormonal signals from hypothalamic-pituitary-gonadal (H-P-G) axis. In the present study, we evaluated the maturation of male rat accessory sex organs during the peripubertal period using tissue weight measurement, histological analysis and RT-PCR assay. Male rats were sacrificed at 25, 30, 35, 40, 45, 50, and 70 postnatal days (PND). The rat accessory sex organs exhibited differential growth patterns compared to those of non-reproductive organs. The growth rate of the accessory sex organs were much higher than the those of non-reproductive organs. Also, the growth spurts occurred differentially even among the accessory sex organs; the order of prepubertal organ growth spurts is testis = epididymis > seminal vesicle = prostate. Histological study revealed that the presence of sperms in seminiferous tubules and epididymal ducts at day 50, indicating the puberty onset. The number of duct and the volume of duct in epididymis and prostate were inversely correlated during the experimental period. Our RT-PCR revealed that the levels of hypothalamic GnRH transcript were increased significantly on PND 40, suggesting the activation of hypothalamic GnRH pulse-generator before puberty onset. Studies on the peripubertal male accessory sex organs will provide useful references on the growth regulation mechanism which is differentially regulated during the period in androgen-sensitive organs. The detailed references will render easier development of endocrine disruption assay.

• Journal of the Korean Society of School Health
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• v.3 no.1
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• pp.119-134
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• 1990

The purpose of this study is to find out the need for sex education of middle school students and their parents. For the data collection, the survey was conducted during the period from September 10 to September 20, 1989 by using prepared questionnaire. A questionnaire was given to 592 students of 1st, 2nd and 3rd grade from four middle schools and to 408 their parents in Suwon City. The major results are summarized as follow; 1. Among the 25 questions were asked about knowledge of sex, the structure of reproductive organs, physical change during puberty, menstruation, Sexually stimulation and family plan were answered correctly by over 50% of the students. The higher the grade, the more the knowledge of sex. There was no significant difference between this knowledge and with eider sister or brother. Among the 20 questions were asked about knowledge of sex, sexually stimulation, pregnancy, emission, induced abortion and sexually transmitted disease were answered correctly by over 50% of the parents. 2. 30 questions were asked about attitude of sex, 47.7% of the students and 53.4% of the parents answered 'positive'. There was no significant difference between grade and sex of students. A significant difference '.vas not also found between years and education level of parents. 3. In case of students, experience of sex education was showed the structure of reproductive organs, physical change during puberty, temper during puberty, menstruation, emission more. In the event of parents, experience of sex education was showed the structure of reproductive organs, temper during puberty, menstruation, emission, relationship with apposite sex more. Most students felt that sex education should begin from the first grade of middle school and the first grade of high school strongly. In parents was showed the need for sex education from the primary school and the first grade of middle school highly. Namely, students and parents felt that sex education should begin from puberty. To help good developments and growth of middle school students with rapid change should be educated sex eduction properly for the occasion.

• Journal of environmental and Sanitary engineering
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• v.16 no.3
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• pp.8-13
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• 2001

This study was carried out effect of red ginseng extract(1.0g/kg) on organotin compounds (10, 20 and 40 mg/kg) which poisons against some organs like thyroid gland, liver, kindey, testis, ovary, serum immuinty and sex hormone activity of rats were examinned by gastric tubing for 3 weeks. The weight of each organ in TBTO treated group were significantly increased other organs which excepted kinedy in males and only liver in females.(p<0.05, p<0.01). In case of Immunity activity of each sex, IgM level was small change comparsion with that of control group in all sex. but IgG level was significantly decreased females rather than males comparsion with that of control group.(p<0.05, p<0.01) In case of sex hormone activity, the testosterone activity of males and the estradiol activity of females were significantly decreased rather than the control group. on the other hand, red singsong treated group was only significantly increased estradiol activity.( p<0.05, p<0.01)

• The Korean Journal of Ecology
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• v.21 no.1
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• pp.27-33
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• 1998

Arisaema robustum, which has the ability to change sex, was studied in a temperate broadleaf forest of Sanseong-ri, Joongbu-myeon, Gwangju-gun, Kyonggi Province, Korea. \ulcornerThe study, carried out from 1993 to 1997, focused on population dynamics energy budget among organs, size distribution, mortality, the relationships between sex and size, seed production and germination rate. In terms of energy budget among the organs, the ratio of aboveground to belowground biomass was 36.6 : 63.4 in non-female plants, and 81.4 : 18.6 in female plants. Also, in female plants, the ration of leaf to sexual organ biomass was 39.5 : 41.9. Therefore, the belowground ratio of female plants was lower than that of non-female plants. Plants were classified into 8 levels relative to the amount of leaf area by $100cm^2$. The rates of the smallest and the largest classes were 49% and 1%, respectively, and population distribution by size was relatively stable. The mortality averaged 13.1% per year and decreased in inverse proportion to leaf size (6.6% in the smallest and 0.0% in the largest size classes). Leaf areas were $64.1{\pm}48.5cm^2$ in non-flowering plants, $232.1{\pm}123.9cm^2$ in males and $444.8{\pm}153.9cm^2$ in females. The increase rates of leaf area per year varied from 1.9% in plants changing from female tomale, to 152.4% in plants changing from non-flowering to female. But plants which remained female for 2 years showed a decrease of 34.7%. >From this result, it is thought that the female plants invest more energy to reproduction than to vegetative organs. The correlation coefficient (CC) value between plant size and the number of seeds produced (0.55) was larger than the CC value between plant size and total seed weight (0.73). That is, the larger the plant size, the heavier the seed produced. The germination rate increased along with seed weight, and it was 95% in plants which were over 60mg fresh weight/seed.

• Journal of environmental and Sanitary engineering
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• v.21 no.2 s.60
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• pp.30-35
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• 2006

The purpose of this study finds out the effect of red ginseng extract (1.0g/kg) on TBTO (10, 20, and 40mg/kg) which poisons against some organs like thyroids gland, liver, kidney, testis, ovary, sex hormone activity of rats are examined by gastric tubing for 3 weeks. The weight of each organ in treated group were increased, especially liver in female and those of testis in males were significantly increased at 10, 20 and 40mg/kg (P<0.05, P<0.01). In case of sex hormone activity of each sex, the estradiol activity of female and testosterone activity of males were significantly decreased rather than the control group (P<0.05, P<0.01) According to between the TBTO treated group and 10+ rGe group of the testosterone activity each sex were significantly increased (P<0.01).

• The Journal of Korean Society for School & Community Health Education
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• v.13 no.2
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• pp.29-44
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• 2012

The purpose of this study is to provide substantial foundation to establish effective sex education plan for female college students. For this purpose, we compared female college students with health related majors and the ones with non-health related majors in knowledge in sex, attitude toward sex, and sexual experience. We took the form of self-recording to survey 269 single female college students. The result is as follows. For knowledge in sex, including reproductive organs, contraception, delivery, sexual disease, and sexual intercourse, students with health-related majors(20.59) gained higher scores than students with non-health related majors(16.82). Scores for attitude toward sex indicated 2.43 for the health related majors and 2.35 for the non-health related majors. Attitude toward pre-marital sex, sex admissibility, and abortion showed especially distinct result between the two groups. Whether a student has ever engaged in sexual intercourse served as a significant variable to determine knowledge in sex overall, and the indexes such as sexual pleasure, chasteness, marital values, and attitude towards sex indicated significant differences. The result may be interpreted that the students with sexual experience tend to show more open attitude toward sex. The result indicated that contraception, pregnancy, and delivery were the parts that the participants most wanted to be educated on. Knowledge in sex is both positively correlated with attitude toward sex and sexual behavior. Also, the result indicates that knowledge in sex, both subjective and objective, significantly affects sexual behavior.

• Journal of Korean Home Economics Education Association
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• v.21 no.4
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• pp.127-144
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• 2009

The purpose of this study was to develop and to examine the effect on sex education program to middle school student. The subjects were 8 grade students and to examine 10 session education. Collected data was analyzed by SPSS WIN 12.0 program. The major results of this study were as follow ; First sex education program was developed into four areas : human and sex psychology, physical development and sex healthy, sex social environment and equality, marriage and healthy family. Included program contents were human dignit communication, sex curiosity, difference of sex, genital organs, pregnancy and birth, family violence, sexual violence, equality, parent-children relationships, family role. Second, sex education program was effective to improve degree of sex knowledge and to change sex attitude. Finally, sex education program needs to be continuously offered even to lower grades in elementary school.

• Journal of the Korean Society of School Health
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• v.3 no.1
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• pp.48-58
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• 1990

This study was attempted to assess the effects of a long term regular sex education on the knowledge about anatomy and physiology of human reproductive organs and the attitude toward sex of second grade high school girls. The study population included 1,678 high school girls(542 educated second grade girls, 972 not educated second grade girls and 164 pre-educated first grade girls) attending in 3 high schools located in Kyungnam province. The data was collected by guestionnaire to assess knowledge of sexual anatomy and physiology and the attitude toward sex from 21 to 24 December 1988. The results were as follows: Most of students (educated group 99.3%, not educated group 98.1%) agreed to necessity of sex education. Among students 70.8% did not talk about their sexual problems with their parents and 30.1% of educated group obtained spxual knowledge from their teachers. There were significant differences between level of knowledge on anatomy and physiology of reproductive organs, secondary growth spurt, V D, pregnancy and contraceptives of educated group and not educated group (P < 0.01). There was significant difference between positive attitude about sexual intercourse before marriage, artificial abortion and family planning slogan of educated group and not educat.ed group (P < 0.05, P < 0.01). There were significant differences between degree of agreement about acquaintance with the other sex, knowledge of acquaintance with the other sex, talk freely with friend, parent and teacher of educated group and not educated group (P < 0.05, P < 0.01). Statistics revealed that high school girls of not educated group had less knowledge about acquaintance with the other sex than educated group (P < 0.01).

• Mycobiology
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• v.31 no.2
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• pp.86-94
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• 2003

The effect of four sub-lethal concentrations(400, 800, 1,200 and 1,600 ${\mu}g/ml$) of three amino acids such as isoluecine, aspartic acid and phenylalanine on vegetative growth and sexual and asexual reproduction of Achlya racemosa, A. proliferoides and Saprolegnia furcata was investigated. The density of vegetative growth and diameters of vegetative colonies of species of the Oomycetes fungi decreased with rising the concentration of the applied amino acid. Vegetative hyphae of treated fungi almost appeared branched in case of S. furcata, thick in case of A. racemosa and distorted in case of A. proliferoides as compared with control. The different treatments with amino acids depressed both sporangial formation and discharge, which were dependent on the tested species of zoosporic fungi, the amino acid and its dosage. Phenylalanine was the most effective amino acid in inhibiting sporulation and S. furcata was the most sensitive fungal species. Aspartic acid and isoleucine stimulated germination of discharged spores through the formation of germlings. Gemmae formation by the three fungi was reduced at the low concentrations of amino acids and nearly missed at high concentrations. Sex organs(oogonia and antheridia) were affected partly; rudiment oogonia were observed at low concentrations(400 and 800 ${\mu}g/ml$) and disappeared at higher concentrations, whereas antheridial branch formation was stimulated as the fungi were treated with isoleucine and to some extent phenylalanine.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.128.3-129
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• 2003

A leaf blight disease caused by a species of Phytophthora has been observed on castor bean plants growing near dwelling houses in Manchon-dong, Daegu since 1993. The first isolate that we have kept was producing papillate, ovoid-obpyriform to obpyriform sporangia with on a simple sympodial sporangiophore from diseased tissue placed on water agar plates. The pure isolate, however, did not sporulate on agar media, and rarely even in water, but produced mycelial swellings and chlamydospores in water. Sporangia measured 26.1-77.4 ${\times}$ 23.2-44.0$\mu\textrm{m}$. Chlamydospores were either terminal or intercalary, and measured 24-29.4$\mu\textrm{m}$ in diameter. Sex organs were not formed in a single culture. In 2003, another pure isolate was isolated from castor bean plants with similar symptoms at the same place. The second isolate was distinct from the first one in that the second isolate was readily and abundantly sporulating on V8 juice agar plates. Sporangia of the second isolate were papillate, ovoid and caduceus with a pedicel. Sporangia measured 19.5-48.8 x 17.6-34.3$\mu\textrm{m}$ with 3.7$\mu\textrm{m}$ high papilla and 4.1$\mu\textrm{m}$ long pedicel. No sex organs were formed in a single isolate culture. Both isolates were pathogenic on castor bean plants. Results of the efforts to identify the two species of Phytophthora will be discussed.