• Title/Summary/Keyword: current control

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Biochemical Effects of ABA and $GA_3$ on the Growth of Rice(Oryza sativa L.) Seedings (ABA와 $GA_3$가 유묘기(幼苗期)의 벼(Oryza sativa L.) 생육(生育)에 미친 생화학적(生化學的) 영향(影響))

  • Shon, Tae Kwon;Lee, Sang Chul;Kim, Kil Ung
    • Current Research on Agriculture and Life Sciences
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    • v.11
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    • pp.31-41
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    • 1993
  • The biochemical effects of ABA and $GA_3$ on rice seedling stages were investigated from two rice cultivars, Dongjinbyeo and Samgangbyeo. Some of the results obtained are as follows ; The shoot growth was significantly increased at all concentrations of $GA_3$ compared to the control but it was completely inhibited by ABA. The root length was not affected by all concentrations of $GA_3$ except for the highest concentration of $10^{-3}M$. ABA had an inhibitary effect on root growth and showed similar trend to the shoot growth. By increasing the concentration of $GA_3$, sugar content of rice seedlings was increased and starch content was decreased. On the contrary, the treatment of ABA revealed that sugar content was decreasing with higher level of starch content. Chlorophyll content was greatly reduced at the all concentrations of $GA_3$ in both cultivars tested. Generally, the responses of root activity decreased with treatment of $GA_3$ but no difference in the activity was observed in Samgangbyeo. Major fatty acids of rice seedlings were investigated as palmitic, oleic, and linoleic acid with little contents of linolenic acid and stearic acid. The contents of these fatty acids were decreased with ABA and increased with $GA_3$ treatment, respectively. A protein band of 24 kD in the electrophoresis was observed with ABA treated rice seedlings but not with $GA_3$.

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A Study OR Investigation of the Factors having Affect on Junior Highschool Boys관 Practice of Health Care (중학교 남학생들의 건강관리 실천과 이에 영향을 미치는 요인 조사 연구)

  • 기경숙
    • Journal of Korean Academy of Nursing
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    • v.15 no.1
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    • pp.59-75
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    • 1985
  • Accepting the health as the fundamental human right, the nation and society came to admit the duty to give it to all the people. Korean government is expanding the Primary Health Care as one of the policies for developing the people's health by the lead of community. Like this current situation the School Health Service which is the center of community Health Service schould be active to keep, promote and maintain the health of students and teachers. This investigation was attempted to help to establish the basis of the Health Education Program which would perform the health education efficiently and bring the reforming of student's health control, by measuring the degree of junior high school student's practice concerning health care and con-firming the relationship of knowledge, concern and level of health. The subjects for this study were made up 296 boys at the third grade in a school, located in Seoul. The tool for this study was questionaire. Data were collected for five days, September 22∼26, 1983. The investigators explained the students how to answer the questions of the survey questionaire and then collected the survey cards immediately. The data were analyzed by means of percentages, Pearson Correlation Coefficient and Stepwise Multiple Regression. The results of this study are as follows. 1. The subjects' reaction to the practice concerning Health Care; According to the average proportion of practice concerning health care, subjects' practice in the aspect of Infectious Disease Care is the highest 82.4% and they showed their practice in the aspect of the accident prevention by 77.5% and in the aspect of mental health by 74.8%. Their practice in the aspect of personal hygiene and daily lifehabit is the lowest 71.2%. 2. Health Knowledge; The whole mark distribution of health knowledge is ranged from the lowest 4 point to the highest, 30 point, therefore point range is 26.0. The Average point is 16.58. 11.2% of students solved more than two thirds of personal knowledge levels. 81.4% of students did more than one third of them. 7.415 of students did less than one third of them. 3. Health Concern; The Students of the average 3.99 point respond positively to the question about the health concern, ‘They think health is more important than money’, this is the highest rate. The students of the average 2.78 respond“when they are sick, they enter the appointed hospital where they own choose”, while it is the lowest. 4. Subjects' response to the health level are at follow: Very healthy 26.0%, healthy 47.0%, less healthy 10.5%, 34.9% of them have ever been sick within two weeks, the number of symptoms they reported amount to 114 and the number of cases poi one person is 0.35. 5. The hypotheses test about the practice concerning health care and the factor which effect on it. 1) The main first hypothesis:“The more knowledge of health the subjects have, the better they practice health care.”was accepted. (r=0.1582, p <0.05) 2) The minor first hypothesis:“The more interest in health subjects have, the better they practice”was accepted. (r=0.4354, p <0.001) 3) The minor second hypothesis;“The healthier subjects are, the better they practice health care”was accepted. (r=0.1069, p<0.05) As other test, partical correlation test is performed in other refine whether health knowledge, a fact influencing the students practice concerning health care, is associated with the practice after controlling the third variables. First, after controlling health concern, the correlation of health knowledge and practice concerning health care was kept. (r=0.1347, p <0.005) Second, after controlling health level, the correlation of health knowledge and practice concerning health care was kept. (r=0.1526, p <0.005) And finally, after controlling economic state, the correlation of health knowledge and practice concern-ing health care was kept. (r=0.1413, p <0.05) Additionally Stepwise Multiple Regression between practice concerning health care and variables. 1.6591 of compliance was explained with the know-ledge (F=5.584, p <0.05), 20.0% of compliance was explained with the health concern added to knowledge. (F=63,213, p <0.005) As the above, health knowledge obviously have effects on the practice about the health care. But, contrary to researcher's expectation, health concern has more affects than health knowledge. Therefore, we must grope the plan to enhance health concern through the regular curriculum and systematic health education for students. Besides, we must study further on, to find the factors which have affect on the practice concerning health care.

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Changes and Improvements of the Standardized Eddy Covariance Data Processing in KoFlux (표준화된 KoFlux 에디 공분산 자료 처리 방법의 변화와 개선)

  • Kang, Minseok;Kim, Joon;Lee, Seung-Hoon;Kim, Jongho;Chun, Jung-Hwa;Cho, Sungsik
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.20 no.1
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    • pp.5-17
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    • 2018
  • The standardized eddy covariance flux data processing in KoFlux has been updated, and its database has been amended accordingly. KoFlux data users have not been informed properly regarding these changes and the likely impacts on their analyses. In this paper, we have documented how the current structure of data processing in KoFlux has been established through the changes and improvements to ensure transparency, reliability and usability of the KoFlux database. Due to increasing diversity and complexity of flux site instrumentation and organization, we have re-implemented the previously ignored or simplified procedures in data processing (e.g., frequency response correction, stationarity test), and added new methods for $CH_4$ flux gap-filling and $CO_2$ flux correction and partitioning. To evaluate the effects of the changes, we processed the data measured at a flat and homogeneous paddy field (i.e., HPK) and a deciduous forest in complex and heterogeneous topography (i.e., GDK), and quantified the differences. Based on the results from our overall assessment, it is confirmed that (1) the frequency response correction (HPK: 11~18% of biases for annually integrated values, GDK: 6~10%) and the stationarity test (HPK: 4~19% of biases for annually integrated values, GDK: 9~23%) are important for quality control and (2) the minimization of the missing data and the choice of the appropriate driver (rather than the choice of the gap-filling method) are important to reduce the uncertainty in gap-filled fluxes. These results suggest the future directions for the data processing technology development to ensure the continuity of the long-term KoFlux database.

The first private-hospital based proton therapy center in Korea; status of the Proton Therapy Center at Samsung Medical Center

  • Chung, Kwangzoo;Han, Youngyih;Kim, Jinsung;Ahn, Sung Hwan;Ju, Sang Gyu;Jung, Sang Hoon;Chung, Yoonsun;Cho, Sungkoo;Jo, Kwanghyun;Shin, Eun Hyuk;Hong, Chae-Seon;Shin, Jung Suk;Park, Seyjoon;Kim, Dae-Hyun;Kim, Hye Young;Lee, Boram;Shibagaki, Gantaro;Nonaka, Hideki;Sasai, Kenzo;Koyabu, Yukio;Choi, Changhoon;Huh, Seung Jae;Ahn, Yong Chan;Pyo, Hong Ryull;Lim, Do Hoon;Park, Hee Chul;Park, Won;Oh, Dong Ryul;Noh, Jae Myung;Yu, Jeong Il;Song, Sanghyuk;Lee, Ji Eun;Lee, Bomi;Choi, Doo Ho
    • Radiation Oncology Journal
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    • v.33 no.4
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    • pp.337-343
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    • 2015
  • Purpose: The purpose of this report is to describe the proton therapy system at Samsung Medical Center (SMC-PTS) including the proton beam generator, irradiation system, patient positioning system, patient position verification system, respiratory gating system, and operating and safety control system, and review the current status of the SMC-PTS. Materials and Methods: The SMC-PTS has a cyclotron (230 MeV) and two treatment rooms: one treatment room is equipped with a multi-purpose nozzle and the other treatment room is equipped with a dedicated pencil beam scanning nozzle. The proton beam generator including the cyclotron and the energy selection system can lower the energy of protons down to 70 MeV from the maximum 230 MeV. Results: The multi-purpose nozzle can deliver both wobbling proton beam and active scanning proton beam, and a multi-leaf collimator has been installed in the downstream of the nozzle. The dedicated scanning nozzle can deliver active scanning proton beam with a helium gas filled pipe minimizing unnecessary interactions with the air in the beam path. The equipment was provided by Sumitomo Heavy Industries Ltd., RayStation from RaySearch Laboratories AB is the selected treatment planning system, and data management will be handled by the MOSAIQ system from Elekta AB. Conclusion: The SMC-PTS located in Seoul, Korea, is scheduled to begin treating cancer patients in 2015.

A Study of Content Analysis on ICU(Intensive Care Unit) Nurses' Knowledge of Basic Nursing Sciences (중환자실 간호사의 기초간호과학 지식의 필요성 분석)

  • Byeon, Young-Soon;Choe, Myoung-Ae;Kim, Hee-Seung;Park, Mi-Jung;Seo, Wha-Sook;Lee, Kyung-Sook;Choi, S-Mi;Hong, Hae-Sook
    • Journal of Korean Biological Nursing Science
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    • v.4 no.1
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    • pp.41-49
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    • 2002
  • The purpose of this study was to identify the knowledge contents of basic nursing sciences needed by nurses in the practices of the intensive care unit(ICU). To attain the goal of this study, the nurses working at 10 hospitals in the areas of Seoul and Kangwon Province were randomly selected. They were primarily interviewed, and the open question was secondarily put to them through the questionnaire. In the process of the 1st interview, the interviewees were asked of the question, "What is the knowledge of basic sciences such as anatomy, pathology, physiology. microbiology, pharmacology and the like thought to be lacking when you communicate with doctors in the ICU and when you carry out your nursing practices in it?" The contents of the interview were tape-recorded. The period of data collection ranged from May 1, 2001 to Sept 30. The interviews were conducted with total of 20 nurses. The open-end questionnaire was secondarily mailed to nurses. 113 questionnaires were returned. 100 questionnaires except 13 ones thought to be poorly completed in content were used for data analysis. Three coders classified data obtained from the interview and the questionnaire research into 5 detailed items relating to such as anatomical physiology, pathology, pharmacology. microbiology and basics of nursing. The three coders had experiences in nursing education of 18 years, 8 years and 6 years, respectively, and of them one coder was professor in basic nursing sciences. Data were statistically treated using frequency analysis and percentage by the SAS program. As a result, the following findings were obtained : It was found that the contents that ICU nurses responded were most needed in the field of Human structure and function were water and electrolytic balance(38%), blood and circulatory system(20%), changer in the patient's skin(12%), the arrangement of the human body(10%) and the endocrine system(10%), nervous system(6%), and assessment of the state of the patient's consciousness(4%). It was found that the contents that ICU nurses responded were most needed in the field of pathology were found to be the process of the progress of the disease(32%), symptoms of the disease(27%), prognosis of the disease(22%), followed by the injury-healing process, clinical pathological examination, and examination by radiation. It was found that the contents that nurses responded were most needed in the field of pharmacology were the effect of drug(25%), the side effect of drug(22%), the relationship between diseases and drug(20%), the relationship between disease-causing bacteria and drug(20%) and chemotherapy(2%). It was found that the contents that ICU nurses responded were most needed in the field of microbiology were the relationship between diseases and disease-causing bacteria(45%), Kinds and characteristics of disease-causing bacteria(18%), infection control(16%), application of the aseptic technique(12%), isolation(9%) and the like. It was found that the basic knowledge that ICU nurses responded were needed were the identification of the patient's current state(36%), understanding of the therapeutic process(22%), the operating principle of medical equipment and instrument(20%), medical terminology(9%), equipment and instrument management(7%), calculation of the dose of injection(2%) and the like.

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The Relationship between Entrepreneurial Education and Entrepreneurial Intentions : Focusing on Moderating Effects of Entrepreneurial Orientation and Environmental Factors (창업교육과 창업의지의 관계: 기업가 지향성과 환경적 요인의 조절효과)

  • Lee, Jae-Seok;Lee, Sang-Myung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.10 no.3
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    • pp.61-74
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    • 2015
  • This study attempts to empirically examine the influence of entrepreneurial education in university on entrepreneurial intentions of undergraduate and graduate students as potential entrepreneur and new moderating factors on the relationship between entrepreneurial education and entrepreneurial intentions. We suggested EO(innovativeness, risk-taking propensity, proactiveness and locus of control) and environmental factors(entrepreneurial family background and resource accessibility) as new moderating factors in the relationship. For this study, the following research questions are raised : First, is there a significant difference in entrepreneurial intentions of enrolled and unenrolled students in entrepreneurial education? Second, does entrepreneurial education affect entrepreneurial intentions positively? Finally, do EO and environmental factors have moderating effects in the relationship between entrepreneurial education and entrepreneurial intentions? In order to test our research model, the current study collected data from 265 undergraduate and graduate students who are majoring in natural sciences or engineering in Seoul National Univ., Hanyang Univ., and KAIST. To investigate our research questions and hypotheses, independent-sample T-test and hierarchical regression analysis were employed. The results of empirical analysis revealed that entrepreneurial education positively related to entrepreneurial intentions and that the relationship between entrepreneurial education and entrepreneurial intentions moderated by EO and environmental factors. First, the result showed the significant difference in entrepreneurial intentions between enrolled and unenrolled students in entrepreneurial education. Entrepreneurial intentions of students who enrolled entrepreneurial education was higher than others. Second, entrepreneurial education affected the entrepreneurial intentions positively. Finally, the moderating effects of innovativeness, risk-taking propensity, proactiveness and entrepreneurial family background among investigated six moderators were significant. entrepreneurial education-entrepreneurial intentions relationship was even stronger under high innovativeness and high proactiveness. But risk-taking propensity and entrepreneurial family background decreased the effect of entrepreneurial education on entrepreneurial intentions.

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Evaluation for Optimization of CT Dose Reduction Methods in PET/CT (PET/CT 검사 시 CT 피폭선량 감소 방법들의 최적화 평가)

  • Do, Yong Ho;Lee, Hong Jae;Kim, Jin Eui
    • The Korean Journal of Nuclear Medicine Technology
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    • v.19 no.2
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    • pp.55-62
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    • 2015
  • Purpose Various methods for reducing radiation exposure have been continuously being developed. The aim of this study is to evaluate effectiveness of dose reduction, image quality and PET SUV changes by applying combination of automatic exposure dose(AEC), automated dose-optimized selection of X-ray tube voltage(CAREkV) and sinogram affirmed iterative reconstruction(SAFIRE) which can be controled by user. Materials and Methods Torso, AAPM CT performance and IEC body phantom images were acquired using biograph mCT64, (Siemens, Germany) PET/CT scanner. Standard CT condition was 120 kV, 40 mAs. Radiation exposure and noise were evaluated by applying AEC, CAREkV(120 kV, 40 mAs) and SAFIRE(120 kV, 25 mAs) with torso phantom compare to standard CT condition. And torso, AAPM and IEC phantom images were acquired with combination of 3 methods in condition of 120 kV, 25 mAs to evaluate radiation exposure, noise, spatial resolution and SUV changes. Results When applying AEC, CTDIvol and DLP were decreased by 50.52% and 50.62% compare to images which is not applying AEC. mAs was increased by 61.5% to compensate image quality according to decreasing 20 kV when applying CAREkV. However, CTDIvol and DLP were decreased by 6.2% and 5.5%. When reference mAs was the lower and strength was the higher, reduction of radiation exposure rate was the bigger. Mean SD and DLP were decreased by 2.2% and 38% when applying SAFIRE even though mAs was decreased by 37.5%(from 40 mAs to 25 mAs). Combination of 3 methods test, SD decreased by 5.17% and there was no significant differences in spatial resolution. And mean SD and DLP were decreased by 6.7% and 36.9% compare to 120 kV, 40 mAs with AEC. For SUV test, there was no statistical differences(P>0.05). Conclusion Combination of 3 methods shows dose reduction effect without degrading image quality and SUV changes. To reduce radiation exposure in PET/CT study, continuous effort is needed by optimizing various dose reduction methods.

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Changes in the Hyperspectral Characteristics of Wheat Plants According to N Top-dressing Rates at Various Growth Stages (밀에서 질소 시비 조건에 따른 생육 단계별 초분광 특성 변화)

  • Jung, Jae Gyeong;Lee, Yeong Hun;Choi, Jae Eun;Song, Gi Eun;Ko, Jong Han;Lee, Kyung Do;Shim, Sang In
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.65 no.4
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    • pp.377-385
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    • 2020
  • Recently, wheat consumption has been increasing in Korea, requiring increased production. Nitrogen fertilization is a critical determinant in crop yield; therefore, it is necessary to optimize the nitrogen fertilization regime with current trends that emphasize the minimum impact of nitrogen fertilizer on the environment. In this study, both nondestructive spectral analysis using a hyperspectral camera and growth analysis were performed to determine the optimal N top-dressing rates after heading. The nitrogen application regimes consisted of three conditions according to the secondary top-dressing rate: N4:3:0 (0 kg 10 a-1), N4:3:3 (2.73 kg 10 a-1), and N4:3:6 (5.46 kg 10 a-1). Subsequently, growth and physiological investigations were performed at the jointing, heading, and ripening stages of wheat, and spectral investigations were conducted. On April 29, as the nitrogen fertilization rate was increased to N4:3:3 and N4:3:6, plant height and grain yield increased by 4% and 8%, and 8% and 52%, respectively, compared to those under N4:3:0. Leaf area index and SPAD value also increased by 13% and 24%, and 32% and 43%, respectively. The R (red), G (green), and B (blue) of leaf color were lowered by 15, 11, and 4 in N4:3:3 and 44, 34, and 18 in N4:3:6, respectively, as compared to the control. Grain yield was the highest at high top-dressing (N4:3:6), however, there was no difference between no top-dressing (N4:3:0) and intermediat top-dressing (N4:3:3). The reflectance analyzed using a hyperspectral camera showed a difference in the near-infrared (NIR) region on March 19, and on April 29, there was a difference both in the visible light region greater than 550 nm and the NIR region. Vegetation indices differed according to fertilization regime, except for the greenness index (GI). The results of this study showed that not only growth and physiological analysis but also spectral indices can be used to optimize the nitrogen top-dressing rate.

Studies on production of nuclear transplanted mouse embryos (핵이식 마우스 생산에 관한 연구)

  • Lee, Byeong-chun;Jo, Choong-ho;Hwang, Woo-suk
    • Korean Journal of Veterinary Research
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    • v.33 no.1
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    • pp.151-169
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    • 1993
  • The present study was carried out to investigate the best condition for nuclear-cytoplasm fusion and in vitro culture of nuclear transplanted embryos and to investigate the production of nuclear transplanted offsprings. The nuclei from 2-, 4- and 8-cell mouse embryos were transferred into enucleated 2-cell embryos, and the reconstituted embryos were submitted to direct current(DC) pulses at output voltage of 1.0, 1.5 and 2.0 kV/cm for 100, 150 and $200{\mu}$ sec to induce cell fusion. 1. The culture of intact or zona cut 2-cell embryos in the medium supplemented with cytochalasin B($5{\mu}g/m{\ell}$) and colcemide($0.1{\mu}g/m{\ell}$)for 30 and 60 minutes did not affect the development to later stage. 2. The in vitro developmental rates of group A(a nucleus from one of the blastomeres was removed) and B(electrofusion of group A) were significantly lower than that of control group(p<0.01). 3. When nuclear transplanted embryos were submitted to electrofusion, the significantly higher fusion rates of 2-cell donor nuclei were achieved at the electric field strength of DC 1.5kV/cm for 100 and $150{\mu}$ sec, DC 2.0 kV/cm for $100{\sim}200{\mu}$ sec than DC 1.0 kV/cm for 100 and $150{\mu}$ sec(p<0.01). The significantly higher fusion rates of 4-cell donor nuclei were achieved at DC 2.0 kV/cm for 100 and $150{\mu}$ sec than DC 1.0kV/cm for $100{\sim}200{\mu}$ sec(p<0.01). These fusion rates in 8-cell donor nuclei were 88.7~99.3%. 4. The developmental potency to blastocyst in 2- and 4-cell donor nuclei was significantly higher in DC 1.0 and 2.0 kV/cm for $100{\sim}200{\mu}$ sec treated group and DC 2.0 kV/cm for 150 and $200{\mu}$ sec treated group (p<0.01). The developmental potency to blastocyst in 8-cell donor nuclei was significantly higher in DC 2.0 kV/cm for $100{\mu}$ sec treated group than in DC 1.0 kV/cm for $100{\mu}$ sec treated group and DC 2.0 kV/cm for 150 and $200{\mu}$ sec treated group(p<001). 5. The developmental potency to blastocyst after nuclear transplantation was significantly higher in 2-cell donor nuclei than in 8-cell donor nuclei(p<0.01). 6. The success rate of nuclear injection into enucleated 2-cell embryos was significantly higher in 2-cell donor nuclei than in 4- or 8-cell donor nuclei(p<0.01). 7. The culture time taken for the nuclear transplanted 2-cell embryos to blastocyst stage was significantly longer in 2-cell donor nuclei than in 8-cell donor nuclei(p<0.01). 8. There was no significant difference in the developmental potency of nuclear transplanted embryos within the concentration of EGF at 0 to 15 ng per $m{\ell}$ of BMOC-3 solution. 9. The production rates of offspring after transfer of nuclear transplanted embryos to recipient mouse were significantly higher in 2-cell donor nuclei than in 8-cell donor nuclei(p<0.01).

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Extracellular $K^+$ Effects on the Mouse Aortic Endothelial Cell Contractility (쥐 대동맥 혈관 내피세포에서 세포 외 $K^+$에 의한 혈관 수축선 조절 기전)

  • 안재호;유지영
    • Journal of Chest Surgery
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    • v.36 no.12
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    • pp.887-893
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    • 2003
  • External stimuli increases intracellular (IC) $Ca^{2+}$, which increases extracellular (EC) $K^{+}$. To verify $K^{+}$ effects on the vascular contraction, we performed an experiment using mouse aortic endothelial cell. Meterial and Method: We examined the mouse aortic contractility changes as we measured the IC $Ca^{2+}$ change and ionic current by using the voltage clamp technique under different conditions such as: increasing EC $K^{+}$, removing endothelial cell, giving L-NAME (N-nitro-L-arginine methyl ester) which suppress nitric oxide formation, Ouabain which control N $a^{+}$ - $K^{+}$ pump and N $i^{2+}$ which repress N $a^{+}$-C $a^{2+}$ exchanger Result: When we increased EC $K^{+}$ from 6 to 12 mM, there was no change in aortic contractility. Aorta contracted with more than 12 mM of EC $K^{+}$. Ace-tylcholine (ACh) induced relaxation was inhibited with EC $K^{+}$ from 6 to 12 mM, but was not found after de-endothelialization or L-NAME treatment. ATP or ACh increased IC $Ca^{2+}$ in cultured endothelium. After maximal increase of IC $Ca^{2+}$, increasing EC $K^{+}$ from 6 to 12 mM made IC $Ca^{2+}$ decrease and re-decreasing EC $K^{+}$ to 6 mM made IC $Ca^{2+}$ increase. Ouabain and N $i^{2+}$ masked the inhibitory effect of endothelium dependent relaxation by increased EC $K^{+}$. Conclusion: These data indicate that increase in EC $K^{+}$ relaxes vascular smooth muscle and reduces $Ca^{2+}$ in the endothelial cells which inhibit endothelium dependent relaxation. This inhibitory mechanism may be due to the activation of N $a^{+}$- $K^{+}$ pump and N $a^{+}$-C $a^{2+}$ exchanger. $a^{+}$-C $a^{2+}$ exchanger.r.