• Korean journal of applied entomology
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• v.59 no.3
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• pp.243-250
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• 2020

Two meridic diets, N4 and N6, containing pinto bean, wheat germ, soybean, whole milk and sucrose as main nutrients were developed for rearing Spodoptera frugiperda (Noctuidae) larvae. Six larval instars were observed when neonate larvae were individually raised on these diets in small petri-dishes (ø 50 × 10 mm, 19.6 ㎤) at 25℃ and 15:9 h (light:dark) photoperiod. The average pupation rate of 97.8% on the N4 diet was significantly higher than the rate of 85.6% on N6 diet. The emergence rates were 92.0% on N4 diet and 93.5% on N6 diet, with a non-significant difference. The larval periods were 17.9 and 17.7 days for females, and 18.7 and 18.5 days for males, for N4 and N6 diets, respectively, with non-significant differences between diets and sexes. The pupal periods on both diets were identical (11.1 days for females and 12.8 days for males), despite differences between sexes. The pupal weights of both sexes on N4 diet were identical with a value of 257 mg, whereas those on N6 diet were 256 and 263 mg for females and males, respectively, with a non-significant difference. The longevity of female adults that emerged on N6 diet was 13.8 days and longer than 8.6 days on N4 diet. The pre-oviposition periods were 5.0 and 4.2 days on the N4 and N6 diets, respectively, with a non-significant difference, however, the oviposition period of 6.5 days on N6 diet was longer than the period of 3.9 days on N4 diet. The effective fecundity on N6 diet was 1,392 eggs (maximum 1,776) and was higher than that of 942 eggs (maximum 1,694) on N4 diet, with a non-significant difference. The egg hatching rates on N4 and N6 diets were 79.2 and 79.8%, and egg periods were 3.0 and 2.9 days, respectively, with non-significant differences.

• Clinical and Experimental Reproductive Medicine
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• v.36 no.2
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• pp.111-119
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• 2009

Objective: The aim of this study was to compare the clinical efficacy of clomiphene citrate (CC) and letrozole combined with gonadotropins for controlled ovarian stimulation (COS) in patients with CC-induced thin endometrium Methods: Fifty-one intrauterine insemination cycles performed in patients who previously had a thin endometrium (<8 mm) to ovulation induction using CC were included in this study. A CC 100 mg/day (CC+gonadotropin group, n=26) or letrozole 2.5 or 5 mg/day (letrozole+gonadotropin group, n=25) was administered on day 3~7 of the menstrual cycle, combined with gonadotropins at dose 75~150 IU every other day starting on day 5~7. We compared total dose of gonadotropin used, endometrial thickness, endometrial pattern, number of follicles ${\geq}14\;mm$ on hCG day, pregnancy rate and multiple pregnancy rate between the two groups, which were statistically analyzed using Mann-Whitney U test or Fisher's exact test, where appropriate. Results: There were no significant differences in clinical characteristics such as age, duration of infertility, number of previous IUI cycles, basal serum hormone levels and cause of infertility between the two groups. In both groups, the endometrium was significantly thicker than that of previous ovulation induction cycles using CC. No significant differences were found in the total dose of gonadotropin used, day of hCG administration, the rate of triple endometrium and pregnancy rate. The number of follicles ${\geq}14\;mm$ was significantly lower ($3.7{\pm}1.7$ vs. $2.8{\pm}1.7$, p=0.03) and the endometrium on hCG day was significantly thicker ($7.7{\pm}1.5$ vs. $9.1{\pm}1.7$, p=0.001) in letrozole+gonadotropin group compared to CC+gonadotropin group. Conclusion: The clomiphene citrate and letrozole combined with gonadotropins appear to avoid the undesirable effects on the endometrium frequently seen with CC for ovulation induction. However, in terms of adequate endometrial development or optimal follicular growth, letrozole may be more beneficial than CC for gonadotropin-combined COS in patients with CC-induced thin endometrium. Further prospective randomized controlled studies in a larger scale will be necessary to confirm our findings.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.1
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• pp.49-56
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• 2010

Objective: To investigate assisted reproductive technology (ART) outcomes in women with WHO class I anovulation compared with control group. Design: Retrospective case-control study. Methods: Twenty-three infertile women with hypogonadotropic hypogonadism (H-H) who undertook ART procedure from August 2003 to January 2009 were enrolled in this study. A total of 59 cycles (H-H group) were included; Intra-uterine insemination with super-ovulation (SO-IUI, 32 cycles), in vitro fertilization with fresh embryo transfer (IVF-ET, 18 cycles) and subsequent frozenthawed embryo transfer (FET, 9 cycles). Age and BMI matched 146 cycles of infertile women were collected as control group; 64 cycles of unexplained infertile women for SO-IUI and 54 cycles of IVF-ET and 28 cycles of FET with tubal factor. We compared ART and pregnancy outcomes such as clinical pregnancy rate (CPR), clinical abortion rate (CAR), and live birth rate (LBR) between the two groups. Results: There was no difference in the mean age ($32.7{\pm}3.3$ vs. $32.6{\pm}2.7$ yrs) and BMI ($21.0{\pm}3.1$ vs. $20.8{\pm}3.1kg/m^2$) between two groups. Mean levels of basal LH, FSH, and $E_2$ in H-H group were $0.62{\pm}0.35$ mIU/ml, $2.60{\pm}2.30$ mIU/ml and $10.1{\pm}8.2$ pg/ml, respectively. For ovarian stimulation, H-H group needed higher total amount of gonadotropin injected and longer duration for ovarian stimulation (p<0.001). In SO-IUI cycles, there was no significant difference of CPR, CAR, and LBR between the two groups. In IVF-ET treatment, H-H group presented higher mean $E_2$ level on hCG day ($3104.8{\pm}1020.2$ pg/ml vs. $1878.3{\pm}1197.7$ pg/ml, p<0.001) with lower CPR (16.7 vs. 37.0%, p=0.11) and LBR (5.6 vs. 33.3%, p=0.02) and higher CAR (66.7 vs. 10.0%, p=0.02) compared with the control group. However, subsequent FET cycles showed no significant difference of CPR, CAR, and LBR between the two groups. Conclusion: H-H patients need higher dosage of gonadotropin and longer duration for ovarian stimulation compared with the control groups. Significantly poor pregnancy outcomes in IVF-ET cycles of H-H group may be due to detrimental endometrial factors caused by higher $E_2$ level and the absence of previous hormonal exposure on endometrium.

• The Korean Journal of Malacology
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• v.32 no.3
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• pp.231-240
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• 2016

Techniques were developed for holding and conditioning of Pacific oysters, Crassostrea gigas, in a closed recirculating system. Experimental adults were used 500 oysters ( x two system, total 1,000 oysters) which were collected in $20^{th}$ March 2016 from long-line aquaculture farm at the south coast of Korea. During conditioning periods concentrated live microalgae as Isochrysis sp. $15{\times}10^7cells/mL$, Tetraselmis sp. $2{\times}10^7cells/mL$ and Pheaodactylum sp. $18{\times}10^7cells/mL$ were added 5 L every day, respectively which micro algae were functioned as diets and biological filter. Over all experimental periods total water exchange rate was 21.3% (daily 0.5%). Over 42 days conditioning, female and male oysters were maturated 90.9% and 94.4%, respectively. Survival rate was 98.7%. Mean shell hight (8.3 mm), total wet weight (19.2 g), meat wet weight (5.0 g) and shell wet weight (13.6 g) were significantly increased (P < 0.05). Water quality parameters including the water temperature ($22.1{\pm}0.4^{\circ}C$), salinity ($24.9{\pm}04$), dissolved oxygen (5.1-7.9 mg/L) and pH ($7.93{\pm}0.15$) were kept stable. Concentration of dissolved inorganic nutrient as ammonia (1.96-0.35 mg/L), nitrite (0.03-0.16 mg/L), nitrate (1.34-0.47 mg/L), DIP (0.42-0.03 mg/L) and silicate (3.83-0.00 mg/L) were significantly decreased throughout experiment except nitrite which was increased (P < 0.05), but nitrogenous components stayed below toxic levels (ammonia 0.0-5.5 mg/L, nitrite 0.0-460.0 mg/L) which indicated that closed recirculation system with microalgae based bio-filter could supply sufficiently environment condition to holding and conditioning of oyster.

• Clinical and Experimental Reproductive Medicine
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• v.19 no.1
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• pp.87-94
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• 1992

From December 1991 to March 1992, 34 anejacuratory patients with spinal cord injury underwent 90 of electric stimulations with Seager NRH model 12. The average patient age was 43.5 years with a range of 23 to 48 years. The level of cord injury was cervical in 7, thoracic in 6, lumbar in 11, lumbosacral in 7 and conus medullaris in 3. The average number of electric stimulation per a patient was 2.65 with a range of 1 to 4. The average voltage and amplitude per a stimulation were 17.72 volts and 309. 89 mAmp with ranges of 5 to 25 volts and 50 to 500 mAmp. The total and motile sperm number were evaluated microscopically and analyzed statistically by paired t-test according to the frequency of electroejaculation, level of cord injury and voiding pattern. The results were obtained as follows. 1. An overall success rate of electroejaculation was 85.3% among 34 patients and 82.2% among 90 electric stimulations. 2. The total and motile sperm number per a stimulation were not correlated the frequency of electric stimulation, level of cord injury and voiding pattern. 3. Complications occured in 10 cases; severe low abdominal pain in 5, hypertension in 2, sweating in 1, headache in 1 and neck stiffness in 1. All the copmlications subsided spontaneously within 5 to 10 minutes after transient interruption of the electric stimulation. In summary, rectal probe electroejaculation is an accepted safe means of procuring sperm from spinal cord injury patients with ejaculatory incompetence. However very poor sperm motility was found and it was not related with the frequency of electroejaculation, level of cord injury and voiding pattern. Further investigation would be needed to conclude and to identify the reasons for impaired sperm motility.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.64-64
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• 2003

대구 인공종묘 생산 기술 개발의 일환으로 수정란에 기생하여 폐사를 유발하는 세균 및 세균 감염 경로를 파악함으로써 수정란의 생존율과 부화율 향상을 위하여 본 실험을 실시하였다. 세균 감염 경로를 파악하기 위하여 난소와 정소 자체 세균 감염 여부를 조사하였다. 일반배지 (BHIA)와 비브리오 선택배지 (TCBS)를 사용하여 세균검사를 실시하였다. 난소의 세균 검사는 생식소 내부를 일부 절개한 후 멸균 roop를 찔러 세균을 검사하였고, 정소는 채정하기 전 복부를 절개하여 멸균 roop로서 적출하여 배지에 도말한 후 배양하였다. 수정란 내 세균 수는 수정란을 각각 20개씩 샘플하여 난 외부에 기생하는 세균을 제거하기 위하여 난소독제로 이용되고 있는 benzalkonium 0.1%로 1분간 소독한 후 멸균 생리식염수로 3회 세척하여 호모게나이즈하여 검사하였다. 호모게나이즈한 액 중 100${\mu}\ell$를 pipetting하여 일반배지(BHIA)에 도말하여 인큐베이터에서 배양하였다. 난소와 정소 내에서 세균이 검출됨에 따라 수정 시 세균 감염을 억제하기 위하여 자외선 살균해수와 일반해수를 수정액으로 사용하여 발생율을 비교 시험하였다. 수정 시간은 1분으로 동일하게 적용하였으며, 수정 용기는 멸균 처리된 일회용 100$m\ell$ 플라스틱 용기를 사용하였다. 수정 후 과다한 정자를 제거하기 위한 세란은 1$\ell$ 멸균 비이커에서 5회 30분 가량 실시하여 정자를 제거하였고 멸균 봉으로 저어주면서 수정란의 점착력을 제거하였다. 수정란은 100$\mu\textrm{m}$ 그물망으로 수정란 유실을 방지한 플라스틱 용기에 수용하여 유효수량 270$\ell$ FRP 수조에 수용하여 3$\ell$/min 환수하였고, 수온은 자연수온 1$^{\circ}C$로 유지하였다. 발생율은 만능투영기로 3회 측정하였다. 수정 후 세균과 기생충에 의한 수정란의 폐사를 억제하기 위하여 수정 직후, 수정 후 1일, 2일째 oxytetracycline과 iodine 처리에 따른 발생율 변화를 조사하였다. 발생율은 만능투영기로 조사하였고, 시험구별로 3회 측정하였다. 경과 일수별로 약제 처리는 약제 미처리 수정란 중 정상적인 발생이 이루어지고 있는 것을 선별하여 조사하였다. 약제 처리에 따른 배체 발생 단계는 수정 후 1일째는 상실기, 2일째는 포배기였다. 수정란 및 대구 자어에서 분리된 V. splendidus 에 의한 폐사를 예방하기 위해 in vivo에서 oxytetracycline 외 5종의 항생제를 대상으로 96well plate에서 최고 농도 250ppm부터 2 fold로 단계 희석하여 $25^{\circ}C$에서 48시간 배양하여 MIC를 조사하였다. 세균 감염경로 파악을 위하여 난소, 정소 및 정자에서 세균을 분리한 결과 일반배지 및 비브리오 선택배지에서 모두 균이 검출되었고, 균 동정 결과 터봇 자어에서 검출된 것으로 보고된(Gatesoupe et al., 1999) V. splendidus로 나타났다. 수정액과 정자 및 미수정란의 세균 분리 결과 일반배지에서 3$\times$10/ml ~ 7$\times$10/ml로 균이 검출되었다. 수정액을 일반해수와 자외선 살균 해수를 사용하여 발생율을 비교한 결과 수정 후 3일째 발생율은 자외선 살균해수 72.3%, 일반해수 52.7%였으며, 수정 후 7일째 40.9%와 25.1%로 자외선 살균해수가 유의적으로 높게 나타났다. 수정 후 경과 일수별로 oxytetracycline과 Iodine을 처리한 결과 수정 직후 처리한 시험구는 7일째 19.8%와 18.9%로 대조구 23.1%와 유의적인 차이가 없는 것으로 나타났다. 수정 후 1일째 처리한 시험구는 54.5%와 56.8%, 수정후 2일째 처리구는 47.9%와 50.6%로 두 시험구 모두 대조구와 수정 직후 처리구보다 유의적으로 높게 나타났다. 수정란 및 대구 자어에서 분리된 V. splendidus 에 의한 폐사를 예방하기 위해 in vivo에서 항생제 종류별 MIC 조사 결과 oxytetracycline이 0.48ppm으로 가장 효과가 높은 것으로 나타났다.

• The Korean Journal of Malacology
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• v.30 no.4
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• pp.303-309
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• 2014

The development of Japanese geoduck, Panopea japonica, grown under culture conditions, has been examined through the morphological characteristics in fertilized egg, larvae and juvenile. Gametes were stripped from ripe broodstock and placed into two separate containers. Eggs were washed through a $40{\mu}m$ sieve and fertilized with dilute sperm solution. Developing larvae were maintained at $19{\pm}1^{\circ}C$. Fertilized eggs with $81.6{\mu}m$ diameter developed to trochophores within 14 h and to D-stage larvae ($116{\mu}m$ shell length) within 27 h. Larvae were spontaneously settled at shell length of $311{\mu}m$ after 20 days. The hatching from fertilized eggs and larval rearing were normally available in $18.5-21.5^{\circ}C$, and the growth was good in a cashmilon substrate, as well as sand. After rearing of day 108 from metamorphosis, the shell length of juvenile P. japonica reached 13 mm, and growth rate of shell length of the juvenile was $117.5{\mu}m/d$.

• Development and Reproduction
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• v.12 no.3
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• pp.207-213
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• 2008

In order to monitor the developmental features of embryos, larvae, and juveniles of chub mackerel, Scomber japonicus, the fertilized eggs were obtained by artificial insemination. The fertilized eggs were spherical in shape and floated separately. Their membrane and yolk having 1 oil globule were transparent. The transparent eggs, having one oil drop in the yolk, were $0.94{\sim}1.02\;mm$ (mean, $0.95{\pm}0.03\;mm$) in diameter. The fertilized eggs started hatching at 51 hrs after fertilization in $20{\pm}0.5^{\circ}C$ water. The total length of the hatched larvae was $2.52{\sim}3.0\;mm$ (mean, $2.75{\pm}0.04\;mm$). At hatching, the larva, with the mouth and anus not opened yet, had yolk sack, $28{\sim}31$ myomeres and eyes with melanophore. Yolk completely 2 days after hatching and the total length of post-larvae $3.12{\sim}3.63\;mm$ (mean, $3.39{\pm}0.05\;mm$). At the 18 days after hatching, the tip of tail became curved at the end and the stems for pectoral, dorsal, and caudal fins appeared. Juveniles, having all firm rays, was $44.12{\sim}58.72\;mm$ (mean $55.95{\pm}6.74\;mm$) in TL 25 days after hatching.

• Development and Reproduction
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• v.15 no.4
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• pp.385-391
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• 2011

Human in vitro fertilization and embryo transfer (IVF-ET) program is a general procedure for infertile couples since first successful delivery on 1978 in UK and Korean first on 1985. Recently in Korea, more than 42,000 cases per year of IVF-ET were performed and showed good pregnancy rates compared worldwide data. The human IVF-ET procedure use many consumables, such as ovum pick-up (OPU) needles, centrifuge tubes, culture dish, ICSI pipette, culture media and ET catheters. Major of these materials are supported by the global companies. Thus, Korean IVF-ET program might be placed unstable situation by global economical risks. These uncertain problems could be overcome by the domestic production of IVF-ET materials and consumables. Two times questionnaires for Korean clinicians and researchers about the domestic production were performed and analyzed. Many of them requested domestic OPU needles, ET catheters, culture media and ICSI pipettes under good quality control and quality assurance system. This trial may be contributed to industrialization and to global competence of Korean IVF-ET program. The results of this survey can be provide a fundamental base for development and production of domestic materials and consumables for human IVF-ET program.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.480-489
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• 2017

We investigated a suitable method for in vitro germination of spores, propagation of prothalli, and the formation of sporophytes in the fern Dryopteris nipponensis Koidz. Spore germination rate was relatively high regardless of culture medium. Prothallus development was faster in Knop medium than in Murashige and Skoog (MS) media. Prothalli used in all experiments were obtained from germinated spores, and were cultivated in different concentrations of media components. The active formation of sexual organs such as antheridium made 1MS medium suitable for prothallus propagation, although there was a lower propagation ratio compared to Knop medium. Growth and morphogenesis of prothalli were most effective on 1MS medium containing 2% sucrose, and 60 mM of total nitrogen source with 20:40 mM ratio of $NH_4{^+}:NO_3{^-}$. To select a suitable soil composition for sporophyte formation, ground prothalli were cultivated on single and mixed soils using bed soil, peat moss, perlite, and decomposed granite for 14 weeks. Bed soil promoted sporophyte formation and growth regardless of single or mixed use. In particular, a mixture of bed soil and decomposed granite in a 2:1 ratio (v:v) led to accelerated sporophyte formation ($0.83/cm^2$).