• Journal of Technologic Dentistry
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• v.28 no.1
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• pp.103-120
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• 2006

In this study, we investigated the growth rate on the basis of the sex and the year among the subjects of the licensed dental technicians from the year 1970 to 2003 in Korea. In line with this investigation, this study aims to provide a basic material with regard to the state of dental technician workforce by sex and to suggest a need to reassignment of workforce by sex in accordance with the specific job description. The results of the study are as follows; First, among the licensed dental technicians from 1970 to 2003, males came to 11,589 and females, 5,976, which shows the number of males are 1.9 times higher than that of females. To put the mean sexual composite from 1970 to 2003, male was 82.9% and female 17.1%, indicating the number of males are 4.8 higher than that of females. Second, Of the mean increasing rate until the year 2003 in contrast to 1970, male was about 351 and female was about 181, which shows the number of males increased 1.94 times higher than the females. Comparing to the mean increasing rate of the last year, female came to 25.56% and male 10.73%, which reveals that the females were about 2.4 times higher than the males. In the case of the growth rate, females increased by 1,196,20 times and the males, 26,41. As a result the growth of females are about 45.3 times higher than the males. Third, in the case of the growth rate from 1980 to 2003, females came to 47.85 times and males 9.16, which shows the growth rate of the females was about 5.2 times higher than the males. In contrast to the year 1987, the growth rate until 2003 shows that the females came to 5,13 times and the males 2.70, which indicates the growth rate of females was about 1.9 times higher than males. Fourth, Compared to the year 1990, the growth rate until 2003 shows that females came to 3.40 times and males 2.03 indicating the growth rate of the females was about 1.7 times higher than males. In contrast to the year 2000, the growth rate till 2003 shows that females was 1,34 times and males 1.15 times increased. Fifth, the ratio of sex by the year among the licensed dental technicians is as follows; ratio of male to female in 1970 was 91.2 to 1. In 2003 the ratio came to 2.0 to 1. The number of growth by sex in 1970 came to 24.0 males to 1 female. But the figure was equalled in 2003.

• Korean Journal of Child Studies
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• v.25 no.4
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• pp.49-70
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• 2004

The sample of this study on sibling relationships consisted of 40 pairs of preschool siblings and their mothers. Results were that elder siblings initiated more behavior, initiated more negative behavior, and responded with more negative or no response to affirmative behavior initiated by the younger siblings. Younger siblings exhibited more responsive behavior, initiated more affirmative behavior, showed more affirmative responses to or imitation of affirmative behavior, and imitation of negative behavior than elder siblings. Male pairs exhibited more physical affirmative interaction than female or male-female pairs. Female pairs exhibited more lingual affirmative interaction than male or male-female pairs. Siblings with similar temperaments showed more boastful or no response to negative behaviors than siblings with differing temperaments. Siblings with differing temperaments exhibited more affirmative behaviors than siblings with similar temperaments.

• Journal of Sericultural and Entomological Science
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• v.27 no.1
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• pp.31-36
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• 1985

Using sexual differences between female and male as the indication of the degree of the physiological distrubance in the sex-limited larval marking strains or sex-limited egg colour strains, it was investigated whether the physiological distrubance caused y the translocated autosome fragment on the W-sex determination chromosome, have an effect on expression of the three quantitative characters; cocoon weight, cocoon shell weight, and cocoon shell percentage in the female silkworm. The mean values of the ratios of female to male the above two experimental groups were 127%, 107%, 85%, in cocoon shell weight, and cocoon shell percentage, respectively. On the other hand, those from the three normal stains, namely the basic stock strains, white egg strains, and hybrids were 129% for cocoon weight, 110% for cocoon shell weight, and 85% for cocoon shell percentage, respectively. From the results, it comes to the conclusion that the translocated autosome fragment on the W-chromosome has no influences on the expression of the quantitative characters of the female silkworm because sexual differences of the sex-limited strains were very similar to those of the three normal strains.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.89-93
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• 2004

A new silkworm variety, Kumhwangjam, with a sex-limited cocoon color for spring rearing season is F$_1$ hybrid between Jam 309, a Japanese race bred from Y1/9153, and Jam 310, a Chinese race from Y1/8586. In the local adaptability test performed at 8 local areas in spring rearing season of 2003, major characteristics of Kumhwangjam were mainly similar to those of the check variety Kumokjam. The new silkworm variety, Kumhwangjam, showed a sex-limited cocoon color: yellow for female and white for male with elliptical cocoon shape. This sex-limited cocoon color can be used as a valuable marker for discrimination between female and male for various purposes.

• Journal of Animal Reproduction and Biotechnology
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• v.34 no.2
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• pp.111-116
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• 2019

This study was conducted to analyze the specific genes associated with sex-determination in Korean native cow. The highly organized spermatogenesis requires accurate spatial and temporal regulation of gene expression, which is governed by transcriptional, post-transcriptional, and epigenetic processes. Recently, farmers have been interested in determining the sexual identity of the calves in their farm. We analyzed the sperm of Korean native and Holstein cows, which were supplied from Hanwoo Improvement Center. We evaluated sperm motility and expression of sperm-specific genes after treating semen with both male- and female reagents. Sperm motility in Korean native cows decreased by approximately 10% in the first 30 minutes after treatment with sex-determination reagent. However, sperm motility of Holstein cows decreased to 60-70% after 15 minutes and to 20-30% after 30 minutes. We selected six specific genes expressing in the spermatozoa to analysis the gene expression level. The Real-time PCR results suggest that the selected genes (Gimap4, Tmeff1, Rac2, Abi2, Rac1, and Clu) were highly expressed in the group treated with the male reagent compared to the group treated the female reagent and to the untreated-group (control). In the present study, we suggest that the selected genes play a pivotal role in sex-determination.

• Korean Journal of Animal Reproduction
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• v.11 no.3
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• pp.218-222
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• 1987

This study was conducted using inbred ICR mice to investigate the sex-ratio of preimplantation mouse embryos. For the investigation of sex-ratio of mouse embryos, the karyotype of embryos collected at 70-72, 74-76, 78-80 and 82-84 hr after HCG injection was analyzed by chromosomal analysis. Eight-cell embryos were cultrued up to blastocyst stage, then divided them into three groups(fast-, intermediate- and slow-) according to the blastocoel formation. The sex-ratio was also investigated by chromosomal analysis. 1. The highest apperance of eight-cell and morula was observed at the embryos collected respectively at 66-68 hr(84.6%) and 82-84 hr(79.3%) compared to any other group. 2. The successful rate of embryos sexing at 4-, 8-cell and morula stage were 23.1% (3/13), 42.1%(138/328) and 32.6%(47/141), respectively. The respective sex ratios (female vs male) of 4-, 8-cell and morula were 66.7:33.3, 49.3:50.7 and 39.5:60.5. 3. Of the 476 eight-cell embryos cultured in vitro, 427(89.7%) embryos were developed to the blastocysts and the number of fast-, intermediate- and show-developing embryos were 139, 144 and 144, respectively. 4. Female to male ratios fo fast-, intermediate- and slow-developing group were 23.0:77.0, 55.2:44.8 and 73.8:26.2, respectively. Significantly higher (P<0.05) number of female (48/65;73.8%) was observed in the group of slow-developing embryo than that out of total number of embryos(82/188;43.6%).

• Journal of Aquaculture
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• v.10 no.1
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• pp.49-54
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• 1997

Characteristics of sex ratio and morphometric traits of induced allotriploid between female rainbow trout, Oncorhynchus mykiss and male cherry salmon, O. masou were performed. Sex ratios in both rainbow trout and cherry salmon were equally 1:1, while hybrid and allotriploid revealed higher proportion of male offspring (p<0.01). Body trait measurements of allotriploid in head hight/head length, length of dorsal fin base/body length and length of pectoral fin/body length were intermediate to their parental species, while in length of upper jaw/head length, allotriploid much more resembled that of rainbow trout. These facts proved that allotriploidization improved characters in sex ratio and morphometric traits compared to those o their parental species.

• Journal of Families and Better Life
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• v.10 no.2
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• pp.51-59
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• 1992

Previous studies indicated that unmarried persons are subject to higher mortality than the married, and that the differentials are more marked for male than for females. There are two major approaches to explaining the marital status differentials in mortality ; selection function and protection function of marriage. Following protection fucntion, this study develops the new "instrumental / expressive sex-role" hypothesis in order to explain why marriage protects males more against death. The hypothesis expects that male's instrumental role and female's expressive role have direct effect as well as indirect effect through social integration on sex differential mortality by marital status. for the hypothesis testing, Korea and US vital statistics and census data are used to compute age-specific , age-adjusted mortality rates and their ratios for persons in different marital status. Major findings are as follows. 1)For both Korea and US being married is more advantageous to males than females, ad being widowed, divorced, and separated is more disadvantageous to males, while being never-married is more disadvantageous to females, 2) For Korea, the never married men and women have the highest mortality rates, 3) For US the never married women have the highest mortality rate, while the divorced, separated, and widowed men have the highest mortality rate. Fro both Korea and US data, selection function is rejected, but instrumental/expressive sex-role hypothesis succeeds in accounting for the sex and marital status differential in mortality.

• Reproductive and Developmental Biology
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• v.28 no.2
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• pp.133-137
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• 2004

Sexing from bovine embryos which were fertilized in vitro implicate a possibility of the sex-controlled cattle production. This study was carried out to investigate the possibility of determining of embryo sex by fluorescence in situ hybridization (FISH) technique. FISH was achieved in in vitro fertilized bovine embryos using a bovine Y-specific DNA probe which constructed from the btDYZ-1 sequences. To evaluate Y-chromosome specificity of the FISH probe, metaphase spreads of whole embryos and lymphocytes were prepared and tested. A male-specific signal was detected on 100% of Y chromosome bearing metaphase specimens. Using the FISH technique with a bovine Y-specific probe, 232 whole embryos of 8 cell- to blastocyst-stage were analyzed. Observing the presence of the Y-probe signal on blastomeres, 102 embryos were predicted as male, and 130 embryos as female. The determining rate of embryo sex by FISH technique was about 93% regardless of embryonic stages. In conclusion, the FISH using a bovine Y-specific DNA probe is an accurate, reliable and quick method for determining the sex of bovine embryos.

• Journal of Digestive Cancer Research
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• v.11 no.2
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• pp.61-65
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• 2023

Globally, esophageal cancer is the seventh most common cancer, and the male-to-female ratio in esophageal adenocarcinoma (EAC) is significantly imbalanced at 4:1 to 8:1. Obesity, reflux, and smoking are known risk factors for this sex difference; however, fully explaining this remains challenging. Studies have investigated the link between exogenous sex hormones and esophageal cancer occurrence. A meta-analysis revealed a lower risk of EAC in female who had undergone hormone replacement therapy. Androgen-deprivation therapy in patients with prostate cancer was associated with a decreased risk of EAC. Tissue-based studies have reported varied results regarding the relationship between estrogen receptor expression and survival in female patients with esophageal squamous cell carcinoma (ESCC). Circulating hormone studies have suggested that higher testosterone and luteinizing hormone levels decreased EAC risk in men, and free testosterone was inversely correlated in female with ESCC. However, a high androgen-estrogen ratio in male patients with EAC was linked to increased odds of EAC. Sex hormones influence carcinogenesis, affecting cell proliferation, differentiation, metabolism, inflammation, and cell death. The studies were limited by the small sample size and varying hormone measurement methods; thus, future studies with definitive conclusions on the association between esophageal cancer and sex hormones are warranted.