• The Korean Journal of Ecology
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• 제18권2호
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• pp.231-241
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• 1995

I examined the relationship between allocations to plant size components such as plant height, total leaf weight, and nuber of branches and to reproductive components such as the number and weight of male and female fowers in three populations of the monoecious, wind-pollinated Ambrosia artemisiifolia. In particular, the two types of gender of plants, phenotypic and functional gender, were related to resource allocation. Mean values of all plant size and reproductive components differed significantly among the three populations. Such inter-population differences did not exist for both photosynthetic and reproductive efforts, Plant size components were mostly positively correlated with reproductive components among plants. However, the relationships between photosynthetic effort and reproductive components were largely negative and inconsistent among populations. The phenotypic gender was much lover than 0.5 in all of the three populations. Pairwise correlations between functional gender and each allocation measurement such as plant size components, reproductive components, photosynthetic effort, and reproductive effort were not consistent across the three populations. These results suggest that the gender of A. artemisiifolia measured as flower production responds sensitively to environmental conditions which might differ whithin as well as among populations.

• Fisheries and Aquatic Sciences
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• 제3권3_4호
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• pp.180-187
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• 2000

Reproductive effort and spawning frequency of the two palaemonid prawns, Exopalaemon modestus and Palaemon gravieri, were investigated. In both embryos of the two species, egg size was larger in E. modestus than in P. gravien but for a given size, number of eggs (EN) was fewer in E. modestus. The statistical results revealed that there were significant differences in egg size and EN between the two species. E. modestus living in freshwater environments had larger and fewer offspring than P. gravieri inhabiting marine environments. These findings are consistent with predictions from r- and K-selections models. Reproductive effort (RE) also was higher in E. modestus, suggesting the possibility for E. modestus to invest larger amount of energy per individual offspring. In the two prawns the ovarian dry weight of females with eyed eggs was significantly higher than those with non-eyed eggs. This indicates that the ovarian maturation occurs during the period between the two embryonic stages, suggesting females being potentially of continuous breeding within a single reproductive period. In the both species brood loss did not occur during the incubation period.

• Ocean and Polar Research
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• 제27권1호
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• pp.67-74
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• 2005

남해안의 동대만과 앵강만에 생육하는 거머리말 개체군의 생물계절학과 생식 능력을 2002년 9월부터 2003년 8월까지 조사하였다. 동대만의 퇴적물 입도는 앵강만보다 세립하였으며, 퇴적물의 유기물 함량도 유의하게 높았다. 동대만의 수온은 $7.5^{\circ}C$(2월)에서 $25.5^{\circ}C$(8월)까지 분포하였으며, 앵강만은$6.7^{\circ}C$(2월)에서부터 $25.2^{\circ}C$(9월)까지 분포하였다. 두 지역의 거머리말 개체군은 다년생의 생활사를 보였으며, 생식지의 생식 능력들은 동대만이 앵강만보다 유의하게 높았다. 동대만의 생식지는 2003년 2월부터 6월까지 출현하였으나, 앵강만에서는 2003년 3월부터 6월까지 출현하였다. 동대만에서 생식지의 생육밀도는 $11{\sim}33%$를 차지하였으나, 동대만에서는 5% 이하로 나타났다. 생식지의 구조적인 특징은 육수화서 내 열매와 종자 수를 제외하고 동대만에서 유의하게 높았다. 두 생육지에서 거머리말 개체군의 생식 단계의 출현 시기는 수온과 관계하는 것으로 사료되었다.

• Clinical and Experimental Reproductive Medicine
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• 제39권2호
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• pp.46-51
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• 2012

Fertility preservation (FP) is an effort to retain the fertility of cancer patients, and as an emerging discipline, it plays a central role in cancer care. Because of improvement in diagnostic and therapeutic strategies, an increasingly large number of patients are surviving with cancer. FP specialists should make an effort to spread the significance of FP among reproductive women with cancer and provide appropriate education both for associated physicians and for cancer patients who wish to preserve their fertility. Physicians who take part in the initial diagnosis and management of cancer should consider the importance of early referral of young cancer patients to FP specialists and take care of those patients by providing timely information and appropriate counseling. Individualized treatment strategies should be delivered depending on the patient's situation with appropriate team approach.

• 한국수산과학회지
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• 제36권2호
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• pp.144-150
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• 2003

Reproductive biology and population dynamics of Latreutes planirostris were investigated on the south western waters of Korea from June 2001 to May 2002. This paper describes sex ratio, population growth, and reproductive aspects of Latreutes planirostris. Brood size was an isometric function of female carapace length. Based on dry weight, reproduction effort (mass of eggs/mass of female) averaged 0.23. Ovarian examination showed that there was significantly higher gonadosomatic index from May to September, with a peak in June. Statistical analysis revealed that the ovarian dry weight of females with eyed eggs was significantly higher than that of those with non-eyed eggs. This suggests that females were potentially consecutive breeders. Sex ratio showed that female is more numerous than male. Growth parameters mortality and recruitment were estimated by monthly length-frequency data. Growth parameters were estimated, using the seasonalized von Bertalanffy growth function model $(L\infty\;=\;12.70\;mm\;CL,\;K\;=\;0.87yr^{-1},\;C\;=\;0.96,\;WP\;=\;0.59)$. The recruitment pattern was twice a year.

• Ocean Science Journal
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• 제43권3호
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• pp.127-133
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• 2008

Reproductive patterns of an epifaunal amphipod, Pontogeneia rostrata, were studied on Dolsando sandy shore in Korea. The life history pattern was iteroparous, with recruitment mainly occurring from winter to spring. The sex ratio was malebiased, especially during breeding periods. The mean body length of females was significantly larger than that of males. Brood size and egg volume were positively related to the body length of ovigerous females. There was no significant difference in brood size between successive breeding periods, but egg volumes were significantly higher in early winter (December) than in late spring breeding (May and June), increasing the probability of survival to hatching. These traits contribute to more reproductive potential in early winter than in late spring breeding. The mean brood size of epifaunal P. rostrata was larger but the mean egg volume smaller than that of infaunal amphipods in this sampling area. We suggest that reproductive effort for epifaunal species may be proportionally greater than for infaunal species in risky environments.

• Ocean and Polar Research
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• 제37권1호
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• pp.49-59
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• 2015

이 연구에서는 바지락의 성 성숙이 활발한 봄철에 경기만 선재도, 전북 곰소만, 및 남해 완도 등, 연중 수온 분포가 다른 지역에 분포하는 바지락 채집하여 P. olseni 감염이 번식에 미치는 영향을 조사하였다. 바지락의 산란은 연중 수온이 곰소나 선재도보다 높은 완도 바지락이 서해안 곰소 및 선재도 바지락보다 빠른 성 성숙 및 산란 활동을 보였다. P. olseni 감염이 바지락의 번식에 미치는 영향은 감염도가 다른 지역에 비해 세 배 이상 높은 완도에서 관찰되었으며, 완도 바지락은 여포 크기, 여포 내 성숙 난의 수 및 번식량 등이 타 지역보다 유의적으로 낮았다. 따라서 P. olseni 감염은 폐사 이외에도 다른 연구에서 밝혀진 바와 같이 번식 활동에 부정적인 영향을 미치는 것으로 확인되었다.

• Ocean and Polar Research
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• 제40권1호
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• pp.15-22
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• 2018

In the present study, we investigated temporal variation in the reproductive effort and biochemical contents in adult Manila clam Ruditapes philippinarum at Shi-Heung-Ri beach on the east coast of Jeju Island. Gonad-somatic index (GSI), a ratio of the egg mass to the total biomass determined using ELISA increased dramatically from late May to June (7.1% to 19.5%). In mid-July, GSI dropped to 15.1%, indicating spawning on a small scale during this period. GSI also declined dramatically from late August (15.5%) to September (4.3%), suggesting that massive spawning occurred during this period. A positive correlation was observed between clam size and potential fecundity, while potential fecundity ranged between 1.19-8.40 million eggs/clam. Total proteins and lipids in the tissue increased from late spring to mid-summer, coinciding with an increase in GSI. Protein, lipid and carbohydrate contents in the tissue were lowest in January, indicating that clams were suffering from poor nutritional circumstances, which may be associated with poor food supply from the environment. Monthly increase and/or decrease in the body weight were closely related to gonad maturation and subsequent spawning, which was also linked to temporal changes in the contents of protein, lipid and carbohydrates in the tissue.

• Clinical and Experimental Reproductive Medicine
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• 제44권4호
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• pp.171-174
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• 2017

While many fertility preservation (FP) options now exist for reproductive-aged cancer patients, access to these services continues to be limited. A comprehensive FP program should be organized to serve oncofertility patients effectively. Also, much effort is needed from various individuals-patients, specialists from various fields, and consultants-to facilitate FP in a timely manner. Various challenges still exist in improving access to FP programs. To improve access to FP treatment, it is important to educate oncologists and patients via electronic tools and to actively navigate patients through the system. Reproductive endocrinology practices that receive oncofertility referrals must be equipped to provide a full range of options on short notice. A multidisciplinary team approach is required, involving physicians, nurses, mental health professionals, office staff, and laboratory personnel. The bottom line of FP patient care is to understand the true nature of each patient's specific situation and to develop a patient flow system that will help build a successful FP program. Expanding the patient flow system to all comprehensive cancer centers will ensure that all patients are provided with adequate information regarding their fertility, regardless of geography.

• Journal of Microbiology and Biotechnology
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• 제13권4호
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• pp.495-500
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• 2003

Tight junctions (TJ) between adjacent Sertoli cells in testis are important for the formation of the blood testis barrier (BTB). In an effort to verify the reproductive health risk of endocrine-active chemicals (EACs), changes in the transepithelial electrical resistance (TER) and the expression of TJ genes were examined by co-planar polychlorinated biphenyl (PCB) treatment in cultured mouse Sertoli cells. Although the increase in TER of Sertoli cells was accelerated by 10 nM co-planar PCB, it was downregulated by 100 nM co-planar PCB. The expression of claudin-1 was downregulated by co-planar PCB in a concentration-dependent manner. On the contrary, the expression of claudin-1 was increased in the Sertoli cells by 10 nM co-planar PCB treatment. These results suggest that the structure and function of TJ may be targeted by co-planar PCB in Sertoli cells. Assessment of the structure and function of TJ in Sertoli cells might be useful for screening the reproductive health risk of EACs.