• Title/Summary/Keyword: cell cycles

검색결과 533건 처리시간 0.048초

IVF, ICSI 또는 TESE-ICSI에서 수정을 유도한 난자의 배아 발생능력 및 임신율 (Embryonic Developmental Capacity and Pregnancy Rates of Fertilized Oocytes in IVF, ICSI and TESE-ICSI Cycles)

  • 박기상;박윤규;송해범;이택후;전상식
    • Clinical and Experimental Reproductive Medicine
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    • 제31권3호
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    • pp.169-176
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    • 2004
  • Objective: This study was performed to evaluate and compare the embryonic developmental capacity and pregnancy rates in conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) with ejaculated sperm or testicular sperm cycles. Materials and Methods: Fertilization was examined in the following morning after IVF (group I), ICSI (group II) or TESE-ICSI cycles (group III). Fertilized oocytes were co-cultured with Vero cells until embryo transfer (ET). On day 2 and $5{\sim}7$, grades of embryos (<4- or $\geq$4-cell) and blastocysts (BG1, 2, 3 or early) were evaluated. Clinical pregnancy rate was determined by detecting G-sac with transvaginal ultrasonogram. We analyzed the results by $X^2$ and Student's t-test and considered statistically significant when P value was less than 0.05. Results: Fertilization rate was significantly higher (p<0.05) in group I ($79.0{\pm}21.2%$) than in group II and III ($56.8{\pm}21.6%$ and $36.7{\pm}25.3%$). Cleavage and blastulation rate of group I ($95.8{\pm}13.8%$ and $59.5{\pm}25.3%$) were significantly higher (p<0.05) than those of group III ($83.4{\pm}18.6%$ and $40.4{\pm}36.5%$). Clinical pregnancy rate was significantly higher (p<0.05) in group I and II (40.7% and 41.7%) than that in group III (12.5%). No differences were found in the rates of multiple pregnancy and abortion among three groups. Embryonic implantation rate was higher in group I ($15.1{\pm}20.2%$, p<0.05) and II ($14.7{\pm}20.6%$, NS) than that in group III ($5.1{\pm}15.6%$). However, embryonic implantation rate was increased in ET with blastocyst(s) among three groups. Conclusions: Fertilized oocytes obtained from TESE-ICSI were harder to be successfully cultured to blastocyst stage for 5$\sim$7 days than that from IVF cycles. However, all blastocyst(s) ET increased the embryonic implantation rate equally in IVF, ICSI and TESE-ICSI cycles.

한국 남서부 갯벌의 저서성 미세조류의 대상분포와 수직분포에 미치는 이화학적 요인의 효과에 관한 비교 (Comparison of the effects of physico-chemical factors on the zonation and vertical distribution of benthic microalgal communities in the tidal flats of south-west Korea)

  • 이학영
    • 한국환경과학회지
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    • 제11권6호
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    • pp.529-535
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    • 2002
  • Efffcts of physico-chemical factors on the zonation and vertical distribution of benthic microalgal communities in the tidal flats of Youngkwang and Canaiin, Korea, were studied. Concentrations of nutrients were low throughout the study period. A 38 species of benthic microaigae was identified. Most of the algae were pennate diatoms with small size. Cell numbers at silty sediments were higher than sandy sediments, and showed high patchy distribution. Zonal distributions of benthic microalgae showed higher variation from silty sediment than sandy sediments. Benthic microalgae showed vertical migration within the upper few mm of sediment with periodicity closely related to tidal cycles. Maximum cells were observed from 0 mm depth both sandy and silty sediments. Cells of benthic microalgae in the 1 - 2 mm depth decreased after desiccation of sediments. The variation of cells was higher at sandy sediments than silty sediments. Cell numbers of benthic microalgae showed no positive relationships with pH and nutrinets except NH$_4$-N.

L-Glutamic Acid 생성균에 관한 연구 1 (Studies on L-Glutamic Acid-Producing Bacteria(I))

  • 홍순우;하영칠;차승희
    • 미생물학회지
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    • 제12권1호
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    • pp.37-51
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    • 1974
  • Three strains which accumulated large quantities of L-hlutamic acid as the chief product of metabolism in the presence of glucose and inorhanic ammonium salt under the aerobic condition sere newly isolated. These strains have the general characters as follows: Gram-positive, short fod-shaped, non-sporulating, non-motile, and facultative anaerobe. A change of cell shates was not almost observed in their life cycles and neither a phenomenon of cell-elongation nor a pleomorphism was recognized in any cases. Together with rigid stability in Gram-stain, these characters as above indicated evidences that newly isolates would belong to genus Brevibacterium clearly differentiated from genus Corynebacterium. At the same time the newly isolates, in addition to nutritional requirement of biotin and thiamine, showed the distinctive character of requirement of special amino acid such as histidine or cysteine for their considerable growth. These physiological characters including nitrates reduction, reaction on milk, and slow formation of acid from sugar also were useful in confirming that these bacteria would be Brevibacterium ammoniagenes.

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부식촉진시험에 의한 콘크리트 내의 철근의 부식 모니터링에 관한 실험적 연구 (An Experimental Study on the Corrosion Monitoring of Reinforcing Steel in Concrete by the Accelerated Corrosion Test)

  • 배수호;정영수;김진영
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.543-548
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    • 2001
  • The corrosion monitoring methods of reinforcing steel in concrete are the various methods such as half cell potential method, galvanic current method, resistivity method, polarization resistance method, AC impedance method and etc. In this study, the corrosion monitoring methods of reinforcing steel in concrete were investigated for the test specimens using corrosion inhibitors, zinc-mortar, zinc-plate, respectively. For this purpose, the accelerated corrosion tests for reinforcing steel were conducted according to the periodic cycles(140 days) of wetting($65^{\circ}C$, 90% R.H.) and drying period(15$^{\circ}C$ , 65% R.H.) for the test specimens. As a result, it can be concluded from the test that half cell potential and galvanic current method as monitoring techniques for corrosion were found to be relatively reliable and easily usable method in the field.

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다수의 동일한 입력원을 갖는 ATM Multiplexer의 정확한 셀 손실 확률 분석

  • Choi, Woo-Yong;Jun, Chi-Hyuck
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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    • pp.435-444
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    • 1995
  • We propose a new approach to the calculation of the exact cells loss probability in a shared buffer ATM multiplexer, which is loaded with homogeneous discrete-time ON-OFF sources. Renewal cycles are identified in regard to the state of input sources and the buffer state on each renewal circle is modelled as a K(shared buffer size)-state Markov chain. We also analyze the behavior of queue build-up at the shared buffer whose distribution together with the steady-state probabilities of the Markov chain leads to the exact cell loss probability. Our approach to obtaining the exact cell loss probability seems to be more efficient than most of other existing ones since our underlying Markov chain has less number of states.

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Update on the Evidence Regarding Maintenance Therapy

  • Lee, Jeong Eun;Chung, Chae-Uk
    • Tuberculosis and Respiratory Diseases
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    • 제76권1호
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    • pp.1-7
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    • 2014
  • Maintenance therapy has emerged as a novel therapeutic paradigm for advanced non-small-cell lung cancer (NSCLC). Maintenance therapy that aims to sustain a clinically favorable state after first-line chemotherapy has two strategies. Switch maintenance therapy entails switching to a new and non-cross-resistant agent in an alternating or sequential manner, on completion of first-line chemotherapy. Continuous maintenance therapy keeps ongoing administration of a component of the current regimen after four to six cycles of chemotherapy, if there is a stable disease, or better response. Both maintenance therapies can be continued, until disease progression. The potential evidence regarding maintenance therapy includes providing the opportunity to receive additional treatment, through sustaining tumor shrinkage, and delayed emergence of tumor-related symptom. Thus far, debates over the parameters used to predict the effectiveness of maintenance therapy, financial burden, and uncertainty of improving the quality of life exist. Despite many debates, maintenance therapy, which is currently recommended, has been disclosed to be beneficial.

Air lift 반응기를 이용한 생물유화제의 연속생산

  • 정혜성;김학주;김봉조;황선희;공재열
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.329-331
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    • 2000
  • A marine bacterium, Pseudomonas aeruginosa BYK-2 KCTC 18012P was immobilized in modified polyvinyl alcohol for the continuous production of rhamnolipids. The stability of rhamnolipids production, the mechanical strength of beads and the scanning electron microscope of immobilized cell were determined in a repeated batch culture. The rhamnolipids production was maintained $80{\sim}90%$ stability of initial production, and the mechanical strength also was stable during the repeated batch culture more than 14 cycles. In the case of SEM studies, the internal distribution pattern of the cell entrapped in modified PVA beads was observed. On the basis of optimal conditions, the continuous culture was investigated in 1.8L air lift bioreactor. The result suggested 0.1g/h rhamnolipids was obtained from 1%(v/v) fish oil continuously in conditions of 1.2L working volume, 0.5vvm and 20ml/h flow rate.

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Ketamine과 Pentobarbitone이 생쥐 난자의 퇴화 및 과립세포의 자연세포사에 미치는 영향 (Effects of Ketamine and Pentobarbitone on Degeneration of Oocyte and Apoptosis of Granulosa Cells in Mouse Ovary)

  • 김종훈;윤용달
    • Clinical and Experimental Reproductive Medicine
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    • 제25권2호
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    • pp.179-187
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    • 1998
  • In mammal, lots of follicles start simultaneously their growth but only a few oocytes are ovulated in every sexual cycles. Most of matured and grown oocytes are destined to degenerate by atresia. However, the molecular and physiological mechanisms are not elucidated yet. The present study was designed to establish an induction method of follicular atresia with ketamine or pentobarbitone and evaluate the effect of these anesthetics on oocyte maturation and granulosa cell apoptosis of the mouse ovarian follicle. The percentages of degenerated oocyte and apoptotic granulosa cell in ketamine treated groups were significantly higher than that in controls (58.9% vs 33.5%, p<0.01, degeneration; 44.9% vs 26.6%, p<0.01, apotosis). Futhermore, it was revealed that the concentrations of progesterone in both groups were markedly higher than that in control. In cunclusion, it is considered that ketamine induce an atresia as pentobarbitone, and may be useful for inducing follicular atresia.

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전기자동차용 Plastic Li-ion battery

  • 한규남;서현미;김재경;김용삼;신동엽;정복환;임홍섭;엄승욱;문성인
    • 한국전기화학회:학술대회논문집
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    • 한국전기화학회 2000년도 전지기술심포지움
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    • pp.51-62
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    • 2000
  • Large plastic Li-ion (PLI) cells (25 to 28-Ah) were fabricated for an EV application. The 28-Ah cells showed high specific energy (160 Wh/kg), high specific power (526 W/g), excellent round-trip energy efficiency $(92\%)$, and low self-discharge rate ($6\%$ in 30 days). A 25-Ah cell of an earlier design showed good cycle life of up to 750 cycles at $100\%$ DOD to $80\%$ of its initial capacity, while cycle life test of a 28-Ah cell of a later design is in progress. Preliminary safety tests were also carried out using 6-Ah cells of a similar electrode design giving very encouraging results for development of a safe hish-energy density PLI battery for EV application.

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스퍼터링으로 증착한 바나듐 텅스텐 산화물 박막의 전기화학적 거동 (Electrochemical Behavior of Vanadium Trungsten Oxide Thin Films Deposited by Sputtering)

  • 박영신;이병일;주승기
    • 한국표면공학회지
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    • 제30권2호
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    • pp.121-127
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    • 1997
  • Vanadium tungsten oxide thin films were formed by RF magnetron sputtering and the effects of tungsten addition on the crystallinity and on the electrochemical behavior were investigated. X-ray analysis revealed that amorphized films could be obtained by tungase addition. In order to investigate the electrochemical behavior of the vanadium tungsten oxide films, electrochemical insertion and extraction of lithium were out in 1m $LiCIO_4$-PC-DME electrolyte using litium metal as a counter electrode. When the tungsten was added to the $V_2O_5$ films, cycling reversibility was considerably improved. Electrochemical test showed the cell capacity of about $70\mu\;Ah/\textrm{cm}^2-\mu\textrm{m}$ when the amount of additive tungseten reached 30 atomic percent. No appreciable degradation of the cell capacity could be observed after hundred cycles of insertion and extration od Li.

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