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Structural and optical properties of Ni-substituted spinel $LiMn_2O_4$ thin films (니켈 치환된 스피넬 LiMn2O4 박막의 구조적, 광학적 성질)

  • Lee, Jung-Han;Kim, Kwang-Joo
    • Journal of the Korean Vacuum Society
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    • v.15 no.5
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    • pp.527-533
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    • 2006
  • Spinel $LiNi_xMn_{2-x}O_4$ thin films were synthesized up to x = 0.9 by a sol-gel method employing spin-coating. The Ni-substituted films were found to maintain cubic structure at low x but to exhibit tetragonal structure for $x{\geq}0.6$. Such cubic-tetragonal phase transition indicates that $Ni^{3+}(d7)$ ions with low-spin $(t_{2g}^6,e_g^1)$ state occupy the octahedral sites of the compound, thus being subject to the Jahn-Teller distortion. By x-ray photoelectron spectroscopy both $Ni^{2+}$ and $Ni^{3+}$ ions were detected. Optical properties of the $LiNi_xMn_{2-x}O_4$ films were investigated by spectroscopic ellipsometry (SE) in the visible?ultraviolet range. The measured dielectric function spectra by SE mainly consist of broad absorption structures attributed to charge-transfer (CT) transitions, $O^{2-}(2p){\rightarrow}Mn^{4+}(3d)$ for 1.9 $(t_{2g})$ and $2.8{\sim}3.0$ eV $(e_g)$ structures and $O^{2-}(2p){\rightarrow}Mn^{3+}(3d)$ for 2.3 $(t_{2g})$ and $3.4{\sim}3.6$ eV $(e_g)$ structures. Also, sharp absorption structures were observed at about 1.6, 1.7, and 1.9 eV, interpreted as due to d-d crystal-field transitions within the octahedral $Mn^{3+}$ ion. The strengths of these absorption structures are reduced by the Ni substitution. Rapid reduction of the CT transition strength involving the eg states for x = 0.6 is attributed to the reduced wavefunction overlap between the $e_g$ and the $O^{2-}(2p)$ states due to the tetragonal extension of the lattice constant by the Jahn-Teller effect.

Studies on the mechanism in the induced to unfertilized eggs(male sterility of Silkworm) by protected environment during pupae period (용기의 보호환경에 따른 불수정란(웅성불임잠)의 유발기구에 관한 조사연구)

  • 윤종관;오준식
    • Journal of Sericultural and Entomological Science
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    • v.15 no.2
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    • pp.9-14
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    • 1973
  • In order to find out effects of the generative power of silk worm moth which have been brought up in the high temperature accommodation at their pupa stage. For this specific study, 9 different kinds of male silk worms have been selected as specimen. All those specimen were brought up in the normal temperature at their larvae stage and after the pupation period they have been accommodated in the condition of high temperature for a certain length in accordance with the study programme. Afterwards, those mlae specimen were copulated with Suwon jam 103${\times}$104 which were all brought up in normal conditions. This study was carried out to find the copulation function as well as the ratio of unfertilized eggs(male sterility test). Results of study have been revealed as follows: 1) Although some differences were observed, male pura which have been brought up in the condition of high temperature shown the low rate of unfertilized eggs rather than those were brought up in the normal conpition. 2) In this group the eclosion(emergency) has been found to be poor rather, than those specimen brought up in normal conditions. 3) The copulation function of Moran, Daedong, J124 and C108 specimen were found to be poor than those of Suwon jam. 4) Fertility rate of Moran, Daedong, J124 and C108 was found to be around 65%. This figure is rather lower than what we normally expect. 5) Unfertilized egg ratio of Moran, Daedong and C108 were found to be around 20% if they were brought up in the condition of high temperature for one day from the time of pupation: 40% at 2 days, and 70% at 3 days duration. More than 3 days treatment has shown no progress in the unfertilized egg ratio. 6) One day's treatment for the pupa at the later stage has shown the unfertilized egg ratio of about 10%; 20% at 2 day's treatment, 35% at 3 day's treatment, 40-60% at 4 day's treatment, more than 60% at 5 day's treatment, and the 70% of fertilized egg ratio was only observed when the treatment days come to 7 days. It was understood that the unfertilized egg ratio was high at the antepupa stage rather than that of post-pupa stage. 7) According to the result of observation the sperm in copulatory pouch and seminal receptacle out of the normal female silk worm which have been copulated with the male brought up in the condition of high temperature at their moth stage. The reproduction system found in the control zone has been found to be normal and the sperm is amountful and active in motion while the sperm found in the treatment to be limited in amount and slow in motion. The observation was made within 5 hours from the copulation. 8) According to the result of observation of sperm of seminal receptacles of the female silkworm moth, and according to that observation of sperm in the seminal receptacle in female silkworm moth, the amount of sperm and mobility in the female moth brought up in high temperature were poor comparing that were brought up in normal temperature zone. Some of them are even found to be no trace of such. 9) Appearance and mosle of the copulatory organ of the male silkworm moth was found to be no anatomical change. 10) Testis of the later pupa stage which was brought up in the high temperature was found to be almost net developed to anucleate sperm and they are degenerated at stage of between maturation division and sperm abnormal stage. Mean time at control zone, the formation of anucleate sperm was already observed.

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Uptake of Fe and Mn in Red Pepper and Tomato Plants under Different Soil Conditions (토양조건에 따른 고추와 토마토의 철 및 망간 흡수특성)

  • Lee, Ju-Young;Sung, Jwa-Kyung;Park, Jae-Hong;Lee, Su-Yeon;Park, Seong-Yong;Lee, Ye-Jin;Kim, Tae-Wan;Song, Beom-Heon;Jang, Byoung-Choon
    • Korean Journal of Soil Science and Fertilizer
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    • v.42 no.3
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    • pp.207-213
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    • 2009
  • This experiment was performed to understand the relationship between uptake of Fe and Mn by plants, red pepper and tomato, and soil physico-chemical properties under different soil conditions at an environmentally controlled chamber in NAAS(National Academy of Agricultural Science) in 2008. After the dipping for 3 days, four treatments, dipping, dipping+aeration, drainage, drainage+aeration, were set up to investigate the changes in soil redox potential and moisture content. Drainage+aeration changed soil to the oxidation condition from 72 hrs of treatment, and soil moisture content was immediately reduced after treatment. Uptake of Fe and Mn of red pepper was investigated with two treatments, soil only and the mixed[soil(50%) : bed soil(35%) : bark(15%)]. Red pepper leaves taken at 30 days after treatment absorbed excessively Mn from the treatment of soil only and the mixed, and thus uptake of iron was strongly reduced. Also, uptake pattern of Fe and Mn of tomato was examined with four treatment, soil only, soil(50%) + rice straw(50%), soil(50%) + compost(50%) and soil + aeration. Contents of Fe and Mn in tomato leaves was measured at 60 days after treatment. Fe content was the greatest in soil(50%) + compost(50%) whereas Mn content was the highest in soil only. As a result of this experiment, plant growth was stronger influenced by soil moisture content than redox potential or porosity, and the oxidation status of soil was likely to promote that plant predominantly absorbed Mn from soil and thus resulted in Fe deficiency.

Determination of the shelf life of cricket powder and effects of storage on its quality characteristics (식품원료용 귀뚜라미 분말의 저장 중 품질특성 및 유통기한 설정)

  • Kim, Dae-Hyun;Kim, Eun-Mi;Chang, Yoon-Je;Ahn, Mi-Young;Lee, Yong-Hwan;Park, Jin Ju;Lim, Jeong-Ho
    • Food Science and Preservation
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    • v.23 no.2
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    • pp.211-217
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    • 2016
  • This study was carried out to determine the shelf-life of cricket powder and investigate the changes in its quality during storage. To determine the shelf-life, cricket powder was stored at temperatures of 25, 35, and $40^{\circ}C$ for 6 months. The changes in quality parameters of the cricket powder, such as moisture content, color, acid value, volatile base nitrogen (VBN), fatty acid, growth of microorganisms, and sensory appeal were investigated. The moisture content of the cricket powder increased during storage but did not show any significant difference at 6 months of storage. L value was increased at $25^{\circ}C$ storage but decreased at 35 and $40^{\circ}C$. However, there were no significant different in a and b values. The acid value decreased more rapidly at higher temperatures, while the VBN content was not changed. The major composition of fatty acids of cricket powder were palmitic acid, oleic acid, and linoleic acid. Their content was not changed at various the storage temperatures. No aerobic and coliform bacteria grew in the powder during the whole storage period. Cricket powder stored at $25^{\circ}C$ and $35^{\circ}C$ showed similar scores in sensory evaluation, but it storaged at $40^{\circ}C$ showed the significant difference (p<0.05). Moisture content, acid value, oleic acid, and flavor were selected as the criteria for shelf-life establishment of cricket powder. Based on these parameters, especially the moisture content, the shelf life of cricket powder was likely to be 18 months when stored at $25^{\circ}C$.

Effects of Aqueous Medicinal Herb Extracts and Aqueous Fermented Extracts on Alcohol-Metabolizing Enzyme Activities (약용식물의 열수추출물과 적정 조성추출물 및 그 발효물이 알콜대사 효소활성에 미치는 영향)

  • Lee, Ka-Soon;Kim, Gwan-Hou;Seong, Bong-Jae;Kim, Hyun-Ho;Kim, Mi-Yeon;Kim, Mee-Ree
    • Food Science and Preservation
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    • v.16 no.2
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    • pp.259-265
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    • 2009
  • To develop an effective anti-hangover product, hot-water extracts of 25 medicinal herbs were screened for inhibition or activation of alcohol dehydrogenase(ADH) and acetaldehyde dehydrogenase(ALDH), and 12 herbs were selected for further study. Chosen medicinal herb extracts(CMHEs) were fermented by Lactobacillus delbruechii subspecies lactis for 10 days at $35^{\circ}C$ after saccharification with nuruk(malt inoculated by 5 types of microbs) for 72 hours at $35^{\circ}C$ and both CMHEs and fermented CMHEs(FCMHEs) were explored for anti-hangover effects in vitro. We found significant ADH inhibition by hot-water extracts of Pueraria thunbergiana, Hovenia dulcis Thunb, Lycium chinense, Glycyrrhiza uralensis, Acanthopanax sessiliflorus, Liriope platyphylla, and Ixeris dentata, and significant ALDH activation by extracts of Acanthopanax sessiliflorus, Lycium chinense, Ixeris dentata, and Polypori umbellati of the Polyporaceae. The ADH effects on CMHE and FCMHE were -20.22% and -62.63% of control values, and the ALDH effects 173.20% and 280.17%, respectively. In rats given 20%(v/v) alcohol(15 mL/kg), FCMHEs significantly decreased blood acetaldehyde concentrations on 3 hours after ethanol administration, in a dose-dependent manner(p<0.05). Notably, blood acetaldehyde concentrations were markedly reduced in animals given FCMHEs(400 mg/kg) compared to levels seen in rats receiving CADB(commercial alcohol detoxification beverage). Thus, anti-hangover effects were promoted by fermentation of certain medicinal herb extracts.

A Comparison of the Results of BPTB and Hamstring ACL Autograft - Function, Stability & Tunnel Expansion - (골-슬개건-골 및 슬괵건을 이용한 전방 십자 인대 재건술의 비교 - 술후 슬관절의 기능, 안정성 및 대퇴, 경골터널 확장정도에 대하여 -)

  • Jung Young Bok;Tae Suk-Kee;Lim Jung Il
    • Journal of the Korean Arthroscopy Society
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    • v.4 no.1
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    • pp.1-6
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    • 2000
  • Purpose : The purpose of this study was to compare the results of ACL reconstruction using bone-patellar tendon-bone to hamstring. Materials and Methods : Thirty-two ACL reconstructions with autogenous BPTB and eighteen reconstructions with hamstring were compared in terms of functional outcome, stability and tunnel expansion. Results : The functional score of BPTB group was higher than hamstring group in OAK(Orthopadishe Arbeitsguppe Knie) and IKDC(International Knee Documentation Committee) system. In BPTB group, OAK scores were 71.6$({\pm}10.0)$ preoperatively and 88.5$({\pm}7.9)$ finally. In hamstring group, OAK scores were 73.9$({\pm}11.5)$ and 82.5$({\pm}12.9)$ respectively. There was no difference in stability checked by either $KT-1000^{TM}$ or stress view. Anterior tibial translation measured by $KT-1000^{TM}$ were 2.4$({\pm}1.8)$mm in BPTB and 2.3$({\pm}2.4)$mm in hamstring group. Anterior tibial translation in stress view were 2.8$({\pm}3.4)$mm in BPTB and 2.8$({\pm}2.5)$mm in hamstring group. There was no difference in tibial tunnel expansion but femoral tunnel was more enlarged in hamstring group than BPTB (P=0.03). Conclusion : As there was no difference in stability between two groups, it seems prudent to select either graft defend on such factors as anterior knee pain, skeletal maturity and cosmetic concern. Tunnel expansion seems not to affect stability, but further study is needed to confirm that decrease of which might improve stability.

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Macrocyclic Complexes of Actinide and Lanthanide Metals (Ⅰ). Formation and Properties of Cation Complexes with Macrocyclic Ligands (악틴 및 란탄족금속의 거대고리 착물 (제 1 보). 거대고리 리간드의 금속착물의 형성과 성질)

  • Jeong, O Jin;Choe, Chil Nam;Yun, Seok Jin;Son, Yeon Su
    • Journal of the Korean Chemical Society
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    • v.34 no.2
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    • pp.143-158
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    • 1990
  • Metal complexes were prepared by reacting uranium (Ⅵ), thorium (Ⅳ) and rare earth metal (Ⅲ) ions including Nd (Ⅲ), Sm (Ⅲ) and Ho (Ⅲ) with macrocyclic ligands including five crown ethers, nine crownands and one cryptand ligands, and subjected to NMR studies in order to examine coordination sites of the ligands and compositions of the complexes formed. Among the marcocyclic ligands, crown ethers and crownand ligands have shown down-field shifts of the methylene protons of the lcigands by forming stable complexes with all the metal ions and the differences of chemical shifts were decreased as increasing of the cavity-size of crown ethers for the same metal ions and decreasing of the atomic number of the rare earth metals for the same ligands. It has been found that crownand 22 gave a stable complex with uranium(Ⅵ) ion by the coordination through both oxygen and nitrogen atoms of the ligand whereas no complex was formed with the rare earth metal(Ⅲ) ions, which on the other hand were found to form stable complexes with cryptand 221. The rest of the crowand ligands have also been found to form stable complexes with uranium(Ⅵ) ion by coordinating through all the oxygen and nitrogen atoms of the ligands whereas no complexes were formed with the rare earth metal(Ⅲ) ions. It has also been shown by 1H-NMR study that uranium(Ⅵ), thorium(Ⅳ) and rare earth metal(Ⅲ) ions formed 1:1 complexes with the macrocyclic ligands except for thorium(Ⅳ) complex of 12C4 in which the mole ratio of metal to ligand is 1:2. More stable metal complexes show larger changes in chemical shifts of the coordinated ligand protons. Finally, the rare earth metal(Ⅲ) complexes of 18C6 have shown ligand exchange reaction with the solvent molecules in acetylacetone solution, which was not observed for the uranium (Ⅵ) complexes.

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MOLECULAR BIOLOGIC ANALYSIS OF FMR-1 GENE TRINUCLEOTIDE REPEATS IN AUTISTIC PATIENTS (자폐장애 환자에서 FMR-1 유전 삼염기 반복의 분자생물학적 분석)

  • Kwak, Ho-Soon;Chun, Hyo-Jin;Chang, Eun-Jin;Kim, Hee-Cheol;Kim, Jung-Bun;Park, Young-Nam;Jung, Chul-Ho
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.11 no.1
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    • pp.3-15
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    • 2000
  • Objectives:There has been a rapid expansion of studies aimed at elucidating the genetic basis of autistic disorder, especially it’ relationship to fragile-X syndrome. The detection of fragile X chromosome(Xq27.3) by cytogenetic analysis has revealed many difficulties in testing. Therefore, to explore the relationship between autistic disorder and fragile X syndrome, this study administered molecular biologic methods which examined an unstable CGG repeat within the fragile X mental retardation-1(FMR-1) gene. Methods:Ninety nine autistic children and eight normal control children were tested. The number of CGG repeats within FMR-1 gene was measured after amplification by PCR, and cytogenetic analysis was also carried out to detect fragile site Xq27.3. Southern blot hybridization, using StB12.3 and/or Pfxa3 probe, was done for the patients showing expansion of more than 50 CGG repeats (premutation). Results:All but two autistic patients had no expansion in CGG repeats by PCR and there was no significant statistical difference in number of CGG repeat in comparison with normal control. Two autistic patients, considered as premutation by PCR analysis, had no full mutation or premutation by Southern blot hybridization. All autistic children tested did not have any abnormal karyotype or fragile site Xq27.3. Conclusions:These results suggest that autistic patients may not have abnormality in FMR-1 gene or abnormal expansion in CGG repeat. In conclusion, fragile X syndrome may not be antecedent of autistic disorder.

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Monitoring of Atmospheric Aerosol using GMS-5 Satellite Remote Sensing Data (GMS-5 인공위성 원격탐사 자료를 이용한 대기 에어러솔 모니터링)

  • Lee, Kwon Ho;Kim, Jeong Eun;Kim, Young Jun;Suh, Aesuk;Ahn, Myung Hwan
    • Journal of the Korean Association of Geographic Information Studies
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    • v.5 no.2
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    • pp.1-15
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    • 2002
  • Atmospheric aerosols interact with sunlight and affect the global radiation balance that can cause climate change through direct and indirect radiative forcing. Because of the spatial and temporal uncertainty of aerosols in atmosphere, aerosol characteristics are not considered through GCMs (General Circulation Model). Therefor it is important physical and optical characteristics should be evaluated to assess climate change and radiative effect by atmospheric aerosols. In this study GMS-5 satellite data and surface measurement data were analyzed using a radiative transfer model for the Yellow Sand event of April 7~8, 2000 in order to investigate the atmospheric radiative effects of Yellow Sand aerosols, MODTRAN3 simulation results enable to inform the relation between satellite channel albedo and aerosol optical thickness(AOT). From this relation AOT was retreived from GMS-5 visible channel. The variance observations of satellite images enable remote sensing of the Yellow Sand particles. Back trajectory analysis was performed to track the air mass from the Gobi desert passing through Korean peninsular with high AOT value measured by ground based measurement. The comparison GMS-5 AOT to ground measured RSR aerosol optical depth(AOD) show that for Yellow Sand aerosols, the albedo measured over ocean surfaces can be used to obtain the aerosol optical thickness using appropriate aerosol model within an error of about 10%. In addition, LIDAR network measurements and backward trajectory model showed characteristics and appearance of Yellow Sand during Yellow Sand events. These data will be good supporting for monitoring of Yellow Sand aerosols.

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A Comparative Analysis of Blood Estradiol-17${\beta}$ Levels According to Varying Regimens of $Clomid^{(R)}$(Clomiphene citrate) Administration in Induced Ovulated Menstrual Cycles ($Clomid^{(R)}$(Clomiphene citrate)의 투여시기와 용량을 변수로 한 혈중 $Estradiol-17{\beta}$의 동태에 관한 연구)

  • Chang, H.J.;Suh, B.H.;Lee, J.H.
    • Clinical and Experimental Reproductive Medicine
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    • v.15 no.1
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    • pp.40-52
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    • 1988
  • Estradiol-17${\beta}$($E_2$) levels in the blood were estimated according to varying the time and amount of the administration of $Clomid^{(R)}$. $Clomid^{(R)}$ were administered on the 2nd, 3rd and 4th menstrual day corresponding to the recruitment period and on the 5th menstrual day corresponding to the selection period of the ovarian follicles, respectively. And $Clomid^{(R)}$ were administered 50 mg, 100 mg and 150 mg/day, repectively. The effects of the sequential HMG to $E_2$ levels in the blood were also estimated. The results were as following : 1. Blood $E_2$ levels according to the day and amount of administration of $Clomid^{(R)}$ were the highest in the group 3(D $2{\sim}6$, 150 mg/day, with HMG) and the lowest in the group 6(D $5{\sim]9$, 50 mg/day, without HMG). $E_2$ levels showed increasing tendency to 0 day. 2. In the cases of the administration of $Clomid^{(R)}$ during the $2nd{\sim}6th$ menstrual day, $E_2$ levels according to the amount were similar among groups and showed increasing tendency daily. 3. In the cases of administration of $Clomid^{(R)}$ during the $2nd{\sim}6th$ menstrual day, $E_2$ levels according to the sequential HMG independent of the amount of $Clomid^{(R)}$ were higher in the with HMG group than without HMG groups. 4. In the case of the administration of $Clomid^{(R)}$ during the $5th{\sim}9th$ menstrual day, $E_2$ levels according to the amount were the highest in the 100 mg/day group and the lowest in the 50mg/day group. 5. In the cases of administration of $Clomid^{(R)}$ independent of the amount during the 5th${\sim}$9th menstrual day, $E_2$ levels according to the sequential HMG were higher in the with HMG group than without HMG group. 6. $E_2$ levels according to the amount independent of the day of the administration of $Clomid^{(R)}$ were the highest in the 100 mg/day group and 150 mg/day, 50 mg/day group in low sequence. 7. $E_2$ levels according to the sequential HMG independent of the day and amount of the administration of $Clomid^{(R)}$ were higher in the with HMG group than the without HMG group. 8. $E_2$ levels according to the day of the administration of $Clomid^{(R)}$ independent of the amount of $Clomid^{(R)}$ and sequential HMG were the highest in the group D 2${\sim}$6 and the lowest in the group D 5${\sim}$9. According to the above results, there were higher $E_2$ levels in the group with sequential HMG than without HMG. Therefore, the hypothesis, postulated initially by the author, was not verified that sequential HMG would not affect the $E_2$ levels which were related to the process of the selection of the ovarian follicle in the connection with 'FSH window'. Because it may be the stimulation after the selection of later predominant follicle. And the highest level of $E_2$ was estimated in the $Clomid^{(R)}$ 150 mg/day group with sequential HMG on the 2nd${\sim}$6th day, and the higher levels were estimated in the 2nd${\sim}$6th day, 3rd${\sim}$7th day and 4th${\sim}$8th day groups than the 5th${\sim}$9th day group. The lower levels were estimated in the $Clomid^{(R)}$ 50 mg/day group without HMG than 100 mg/day and 150 mg/day on the 5th${\sim}$9th day. Therefore, further study will be needed that combines analyses of the E2 levels in the blood according to the various administration of $Clomid^{(R)}$ with or without sequential HMG and determination of the numbers and size of the ovarian follicles by ultrasonogram.

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