• 한국잠사곤충학회지
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• 제29권2호
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• pp.24-30
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• 1987

잠업시험장에서 육성중인 한성흑란계통잠의 실용형질향상을 위한 효율적인 교잡방법의 탐색을 위해 동아구교잡, 연속교잡, 단계 및 복계여교잡의 4가지 육종방법이 교잡원종세대(P)로부터 F6세대까지 비교검토되었다. 1. 화용비율의 경우 4가지 육종방법 공히 세대간에 또는 교잡방법간에 매우 변화가 심하였고 교잡효과의 양상은 연속교잡>동아구교잡·복계교잡>단계여교잡의 순으로 낮아졌다. 2. 전견중, 견층중, 견층비율의 경우 동아구교잡을 제외한 3가지 방법 공히 비교적 우수한 육종방법으로 생각된다. 3. 세대별 형질발현의 추이를 보면 화룡비율은 세대별 변화가 매우 심하여 일정한 경향이 없고, 전견중, 견층중, 견층비율은 교잡방법에 불구하고 P세대에서 F2,세대간은 교잡효과가 급상승하나 그 이후세대에서는 매우 둔화되는 양상을 보였다. 4. 육성중인 본 근성흑란계통누에의 실용형질은 육성중인 비전좌계통의 원종과 대차없다. 5. 본 근성흑란 암누에의 실용형질 발현도(E)는 정상잠에 가까워 전좌염색체편에 의한 생리적 결여가 매우 미소한 것으로 생각된다. 6. 이상의 결과에서 F7세대 이후의 근성흑란계통 누에의 실용형질 향상은 교잡육종에 의한 계통분리법이 좋을 것으로 생각되고, 아울러 형질고정도도 향상시켜야 할 것으로 생각된다.

• 한국가축번식학회지
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• 제21권2호
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• pp.85-93
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• 1997

These experiments were carried out to examine the development capacity of sexed and then bisected embryo from 8-cell to morula stage. Antisera to histocompatibility-Y(H-Y) antigen were prepared in inbred SD female rat by repeated immunization of spleen cell or testis supernatant from males of same strain. Male and female embryos were separated by delaying development of embryos against H-Y antibody. After sexing, rabbit embryos were bisected and aggregated. The results obtained from the these experiments were summuerized as follows: 1. When mouse and rabbit 8-, 16-cell and morular embryos were culature in H-Y antiserum, the ratio of embryo which has developed to hatching blastocyst was 53.4, 46.3 and 57.4% in mouse embryos, and 49.0, 52.0 and 61.0% in rabbit embryo, respectively. The ratio of mouse and rabbit embryos developed to hatching blastocyst showed nearly natural sex rate(50%), except rabbit mourla showed a little higher ratio(61.0%) as compared to natural sex ratio. 2. When rabbit demi-embryos from 8-, 16-cell embryo and morula were cultured, the percentage of demi-embryos was 70, 68 and 58% without zona pellucida removed, and 62, 69 and 51% with zona pellucida. The rate of aggregation was higher in 8- and 16-cell demi-embryos than in morula demi-embryo. 4. When sexed-demi-embryo was aggregated with another demi-embryo with demi-embryo with same sex, the rate of embryo developed to blastocyst was 60, 50 and 25%, respectively. Eight-cell demi-embryo showed highest rate. In conclusion, it showed that H-Y antiserum which was made by rat spleen cell enabled sexing rabbit embryos. And when rabbit sexed 8-, 16-cell and morula demi-embryo were aggregated, they were developed to eu-blastocyst which suggested the potential of sexed embryo manipulation.

• 한국가축번식학회지
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• 제3권1호
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• pp.56-60
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• 1979

This study was carried out to find the difference between the naturaly born sex rtio among 1,242 head of pigs(120 litters) at Swine Farm, Cheil Sugar Co. and B-body a, pp.arance from their semen, and to find the conception rates which were inseminated to 40 sows with sperm from the anode and cathode after electrophoresis of boar semen. In order to the electrophoretic separation, the semen was placed into the platimum loop electrodes(105 cc) at room temperature for 30 minutes with D.C. 3V. and 350${\mu}$A. constant. The sperm fluorescent staining method was performed in accordance with Bhattacharya's(1970) method. The spermatozoa were observed through a Olympus Vanox microscope(made in Japan) using exciter filter with I heat barrier HPO 120. The results obtained were summarized as follows: 1. The natural sex ratio of 1,242 piglets(120 litters) which were born at Swine Farm, Cheil Sugar Co. was 50%, and B-body a, pp.arance of its boar semen were 49.24%. 2. With electrophoretic separation, the anode and cathode attracted 65.5${\pm}$5.03% and 29.89${\pm}$4.29% of B-body bearing sperm, respectively. 3. After electrophoresis of boar sperm, they were inseminated to 40 sows with sperm from anode and cathode. The conception rate was 92.5%.

• Journal of Periodontal and Implant Science
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• 제51권1호
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• pp.30-39
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• 2021

Purpose: The present study was undertaken to examine whether periodontal probe visibility (PV) accurately reflects gingival thickness (GT) and to identify factors affecting PV using cluster and multivariate analyses. Methods: The clinical characteristics of the maxillary central incisors (n=90 subjects) were examined. Clinical photographs, sex, PV, probing depth, gingival width, papilla height, GT as measured with an ultrasonic device, and the ratio of crown width to crown length were recorded. Multivariate analysis, using multinomial baseline-category logistic regression, was used to identify factors predictive of PV. Cluster analysis was used to identify gingival biotypes. Results: In the multivariate analysis, sex was the only significant predictor of PV (odds ratio, 6.48). Two clusters of subjects were created based on morphometric parameters. The mean GT among cluster A subjects was significantly lower than that among cluster B subjects (P=0.015). No significant difference was found between cluster A and B subjects in terms of PV score (P=0.583). Conclusions: Periodontal PV was not associated with GT as measured directly using an ultrasonic device. Sex was a highly significant predictor of periodontal PV. GT was found to be correlated with morphological characteristics of the periodontium.

• 동의생리병리학회지
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• 제31권3호
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• pp.194-199
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• 2017

This study aimed to identify the effects of lifestyle on Mibyeong, and provide basic data for health promotion activities for management of Mibyeong. A total of 405 data were analyzed for Daejeon University employees from July, 2015 to Jan, 2016. In this study, we collected the data about sex, age, BMI, dietary habit, physical activity, smoking, drinking, and Mibyeong index. There was a difference between Mibyeong groups according to irregular eating, eating of night snack, and smoking for men, while overeating, irregular eating, and physical activity for women. Logistics regression analysis, adjusting for sex and age, was used to estimate related factors of Mibyeong. Compared to the healthy group, Mibyeong 2 group tended to overeat 4 times a week with odds ratio of 3.52, eat irregularly with odds ratio of 2.67, lack of physical activity with odds ratio of 3.30, and to smoke with odds ratio of 3.07. This study suggests that lifestyle, particularly dietary habit, physical activities, and smoking, might be significantly associated with Mibyeong. Good lifestyle could help prevent Mibyeong.

• 대한가정학회지
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• 제38권10호
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• pp.181-197
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• 2000

The purposes of this study were to compare financial status of home-based family business with that of ensile family business, and to analyze the factors effected on financial status of both business groups. The sample consisted of 295 home-based family business and 418 ensile family business among self-employed household of 1998 Korea Household Panel Data, and analyzed into Frequencies, Percentile, t-test, $\chi$$^2$-test and Regression. The findings were as follows: First, in case of financial status of household, there was no significant difference between home-based family business and ensile family business. Second, in case of financial status of business, total sales amount and net profit of home-based family business were lower than those of onsite family business, however net profit to total sales ratio of home-based family business was higher than those of onsite family business. Third, the factors contributing to total expenditure to total income ratio of home-based family business were business owner's present economic perception, future economic expectancy and residence, while business owner's age, the number of children and of tamer, and residence were significant variables contributing to same ratio of onsite family business. The factors contributing to total asset to total debt ratio of home-based family business was only business owner's future economic expectancy, however factors affected on the counterpart were business owler's future economic expectancy and job type of family business. Fourth, the variables of sex, age, educational level of family business owner, job type and family type of family business were associated with net profit to total sales ratio of home-based family business, and sex, educational level of family business owner, job type of family business, and the number of employees were related to same ratio of the counterpart. In addition, educational level of family business owner, job type and residence were related with total sales to the number of employees ratio of home-based family business, and educational level of family business owner and job tape of family business were related to same ratio of ensile family business.

• 환경생물
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• 제22권2호
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• pp.321-328
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• 2004

The effects of Di (2-ethylhexyl) phthalate (DEHP) on the fourth instar larvae of Chironomus riparius were tested in the laboratory. Employing a waterreplacement exposure setup, chironomids were subjected to various concentrations. In the most treatments mortality reached a statistically significant difference from the control conditions. As DEHP concentrations were increased, the rates of emerged adults decreased. Sex ratio was unaffected with little deviation from a 1:1 relationship (except in 1 and $30\mu{g}\;L^{-1})$. The developmental stages was delayed at low concentration (0.3 and $1\mu{g}\;L^{-1})$. Generally the emergent period was different between males and females, and the first emergent day of males was faster than females. The body shape of female adults was larger than males. Differences between males and females were found in body volume, body length and body width. In addition, the body volume showed the significant difference between controls and treatments, and those especially well observed females.

• Animal cells and systems
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• 제16권2호
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• pp.135-144
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• 2012

$Dendronephthya$ $castanea$ Utinomi, 1952 is a member of the family Nephtheidae, and dominates shallow waters adjacent to the southern part of Jejudo Island, Korea. This species is a gonochoric internal brooder with a sex ratio of 1:1, and releases planulae around the time of the full and new moon from July to September, when the seawater temperature peaks. The gametogenic cycle is annual, and oogenesis (12 months) is longer than spermatogenesis (4-5 months). No difference in reproductive features including sexuality, sex ratio, gametogenesis and gametogenic cycles was found between the sympatric species $D.$ $castanea$ and $D.$ $gigantea$, and there was no temporal reproductive isolation. Investigation of the morphological taxonomy and molecular biology of these species indicates that they have very similar or identical traits, suggesting an absence of speciation and a need for taxonomic reclassification.

• 한국잠사곤충학회지
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• 제13권2호
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• pp.151-154
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• 1971

In the silkworm egg production, cutting of the cocoon's edge formed by silkworms forced to aid the emergence, and emergence is related to the amount of alkaloid liquid in the sucking stomach in certain varieties. In this study, there was no difference between cutting of portion and sex, and no significant between cutting of both sides and one side cocoons when comparing their emergence ratio. Expenditures and emergence ratio between both sides and one side cutting off must be studied in coming future.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.42.2-42
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• 1999

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