• Title/Summary/Keyword: Ryu-Hee

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Electron Emission Properties of CNT Arrays Grown with MIcro Molding In Capillary (MIMIC) Assisted Process

  • Lim, Han-Eol;Ryu, Je-Hwang;Lim, Joon-Won;Son, Byoung-Taek;Lee, Yi-Sang;Jang, Jin;Park, Kyu-Chang
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1535-1538
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    • 2008
  • Carbon nanotube arrays were fabricated using micro molding in capillary (MIMIC) process. Patterns remained on the surface in the pattern complementary to that present in the mold. CNTs were selectively grown on the MIMIC patterned sites with a triode PECVD. And turn on field for $10\;{\mu}A/cm^2$ electron emission current was $2.2\;V/{\mu}m$ turn on field.

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Magnetic Resonance Imaging: Historical Overview, Technical Developments, and Clinical Applications

  • Jahng, Geon-Ho;Park, Soonchan;Ryu, Chang-Woo;Cho, Zang-Hee
    • Progress in Medical Physics
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    • v.31 no.3
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    • pp.35-53
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    • 2020
  • The authors congratulate the cerebrations for the 30 years of the Korean Society of Medical Physics (http://www.ksmp.or.kr/). The paper is published to recognize the anniversary. Geon-Ho Jahng invited Professor Z. H. Cho to join to submit this manuscript because he has been one of the leaders in the field of magnetic resonance imaging (MRI) during the last 40 years. In this review, we describe the development and clinical histories of MRI internationally and domestically. We also discuss diffusion and perfusion MRI, molecular imaging using MRI and MR spectroscopy (MRS), and the hybrid systems, such as positron emission tomography-MRI (PET-MRI), MR-guided focused ultrasound surgery (MRgFUS), and MRI-guided linear accelerators (MRI-LINACs). In each part, we discuss the historical evolution of the developments, technical developments, and clinical applications.

Anxiolytic effect of Albizzia julibrissin using elevated plus-maze in rats

  • Oh, Jin-Kyung;Ahn, Nam-Yoon;Oh, Hye-Rim;Oh, Hee-Kyung;Jung, Ji-Wook;Ryu, Jong-Hoon
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.393.2-393.2
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    • 2002
  • Benzodiazepine is a widely used anxiolytic agent. However it has been reported that most anxiolytics have side effects such as hypotension, depression of respiration. dizziness. headaches. chronic sleep disorders. drug poisonings. and withdrawal symptoms. In this report. we want to evaluate the anxiolytic effect of Albizia julibrissin (AJ), There are various reports that AJ has several biological activities such as sedative action. insomnia. irritability, anorexia and diuretic action. (omitted)

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Reality and Meaning of Medicinal Treatments Appeared in Medicinal Fables - Based on Case Study of Ryu Ei-Tae Medicinal Tales (의료설화에 나타난 의학적 처치의 사실성과 의미 - 류의태 의료설화 사례를 중심으로)

  • Ku, Hyun-hee;Ahn, Sang-woo
    • The Journal of Korean Medical History
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    • v.23 no.1
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    • pp.11-22
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    • 2010
  • This study finds an interesting fact that five symptoms (smallpox, postpartum pain, eye disease, swollen symptom and parasite infection) mentioned in Ryu Ei-Tae Medicinal Tales and his prescriptions (steamed rice, loess, soybean sprouts, cinnabar, radish, sesame oil and pork) were dramatized on the basis of traditional Korean medicinal knowledge in the Joseon Dynasty. Based on the study of experience-based medicinal literatures popular in the Joseon period, it is confirmed that the prescriptions are actually effective. Also it is inferred that popular diseases at that time were abscess, difficult baby delivery, postpartum pain and parasite infection, which were regarded as almost incurable diseases to ordinary people. These stories also showed destitution of common people who could not afford to buy medicines at that time. As shown in the Ryu Ei-Tae Medicinal Fable, many people might try various ordinary materials around them such as soil or nose wax. One of the outcomes of this study is that the fact that the tales mentioned common materials easy to get in the surroundings such as steamed rice, sesame oil, soybean sprouts or radish could be interprets as care and consideration of medicinal doctors for ordinary people at that time.

Selective Growth of Carbon Nanotubes and Its Electron Emission Properties

  • Ryu, Je-Hwang;Kim, Ki-Seo;Yu, Yi-Yin;Moon, Jong-Hyun;Park, Kyu-Chang;Jang, Jin
    • 한국정보디스플레이학회:학술대회논문집
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    • 2006.08a
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    • pp.1229-1232
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    • 2006
  • We have grown well-aligned carbon nanotube arrays on the selective areas by plasma enhanced chemical vapor deposition at the substrate temperature of $580\;^{\circ}C$. The selective areas for CNTs growth can be defined by photo lithography technology. The CNTs are uniformly grown on the areas regardless of island diameters. Electron emission currents were measured in a vacuum with a diode structure at room temperature. Uniform electron emission currents were achieved with $40\;{\mu}m$ island spacing with $5{\mu}m$ island diameter.

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Growth of Vertically Aligned CNTs with Ultra Thin Ni Catalysts

  • Ryu, Je-Hwang;Yu, Yi-Yin;Lee, Chang-Seok;Jang, Jin;Park, Kyu-Chang;Kim, Ki-Seo
    • Transactions on Electrical and Electronic Materials
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    • v.9 no.2
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    • pp.62-66
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    • 2008
  • We report on the growth mechanism of vertically aligned carbon nanotubes (VACNTs) using ultra thin Ni catalysts and direct current plasma enhanced chemical vapor deposition (PECVD) system. The CNTs were grown with -600 V bias to substrate electrode and catalyst thickness variation of 0.07 nm to 3 nm. The CNT density was reduced with catalyst thickness reduction and increased growth time. Cone like CNTs were grown with ultra thin Ni thickness, and it results from an etch of carbon network by reactive etchant species and continuous carbon precipitation on CNT walls. Vertically aligned sparse CNTs can be grown with ultra thin Ni catalyst.

Effects of Duchesnea indica on Human Stomach Cancer Cells(KATOIII) (사매의 KATOIII 위암세포(胃癌細胞)에 대(對)한 항암효능(抗癌效能))

  • Lim, Joong-Hwa;Kim, Jin-Sung;Yoon, Sang-Hyub;Ryu, Ki-Won;Ryu, Bong-Ha
    • The Journal of Internal Korean Medicine
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    • v.26 no.2
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    • pp.302-309
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    • 2005
  • Background : Death by cancer, malignant tumor, is on the increase around the world. In South Korea, cancer is the number one cause of death, and, in South Korea, stomach cancer is the most common form of cancer. This may be due to genetic and enviornmental factors. Because stomach cancer is so prevalent here, this study was undertaken. Objectives: This study was conducted to investigate the anti-cancer effects of Duchesnea indica(Andr.) Focke. in human stomach cancer cells(KATOIII). Materials & Methods: For human stomach cancer cells KATO III cells were obtained from Korea Cell Line Bank. The water decoction of Duchesnea indica(Andr.) Focke was added to cultures. First, morphological changes were examined under an inverted microscope. The destruction of stomach cancer cells was measured through Trypan blue exclusion testing, and suppression of viability of stomach cancer cells was measured via MTT assay. Anti-cancer mechanisms were assessed by analyzing the cell cycle. Results & Conclusions : In morphologic change, stomach cancer cells showed the withdrawn and floating appearance that is typical in cellular impairment. In each test group more stomach cancer cells were killed than in the control group to a statistically significant degree. Each test group showed more suppression of viability of stomach cancer cells than that of the control group to a statistically significant degree. Analysis of the cell cycle showed that Duchesnea indica(Andr.) Focke inhibited division of stomach cancer cells. This experiment yielded empirical evidence for Duchesnea indica(Andr.) Focke as a statistically significant anticarcinogen, specifically against stomach cancer.

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Effects of Duchesnea Indica of Colorectal Adenocarcinoma Cells (사매가 대장암 세포에 미치는 영향)

  • Lee, Do-Hyoung;Kim, Jin-Sung;Yoon, Sang-Hyub;Ryu, Ki-Won;Ryu, Bong-Ha
    • The Journal of Internal Korean Medicine
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    • v.26 no.2
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    • pp.310-319
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    • 2005
  • Objectives: The aim is to identify any anti-tumor effects of Duchesnea indica(Andr.) Focke on colon cancer cells. Materials & Methods: Colo201 human adenocarcinoma cells were obtained from American Type Culture Collection. The boiled extract of Duchesnea indica(Andr.) Focke was added (10 and 20 microliters) to cultures and observed at 0, 6, and 12 hours, and at 12-hour intervals thereafter. Morphological changes in colon cancer cells were observed through an inverted microscope, Destruction of colon cancer cells was measured through Trypan blue exclusion testing. Suppression of the viability of colon cancer cells were measured via MTT assay. Anti-cancer mechanisms in the cell cycle of colon cancer cells were analysed via flow cytometry. Results: After introduction of Duchesnea indica(Andr.) Focke to cultures several changes were seen. Significant atrophy of the nucleus and cytoplasm of colon cancer cells was observed, indicating cell injury. Destruction of colon cancer cells was observed in direct proportion to dosage and duration. Suppression of viability of colon cancer cells for each test group was greater than that of the control group increasingly over time(36h, 48h, 60h, 72h), which was statistical significant (p<0.05). Cell numbers of the mitosis phase of the colon cancer cell cycle reduced. Conclusions: Statistcally significant anti-tumor effects of Duchesnea indica(Andr.) Focke were observed in this in vitro experiment. Results support a role for Duchesnea indica(Andr.) Focke in treatment of colon cancer. though it will required progressive research to develop a practical treatment.

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The Effects of Strychni Ignatii Semen on Toxicity Levels and Gastrointestinal Tract (보두(寶豆)의 수치법(修治法)에 따른 독성(毒性) 및 소화기계(消化器系)에 미치는 영향(影響))

  • Kim, Jin-Sung;Yoon, Sang-Hyub;Ryu, Bong-Ha;Ryu, Ki-Won;Cho, Yu-Kyung
    • The Journal of Internal Korean Medicine
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    • v.23 no.1
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    • pp.107-115
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    • 2002
  • Objective : These experiments were designed to investigate the effects of Strychni Ignatii Semen on the gastrointestinal system and declining of toxicity. About experiments of acute toxicity, I investigated the quantity of Strychni $(C_{21}H_{22}N_2O_2)\;and\;LD_{50}$. In order to study the effects on gastrointestinal tract, I investigated the changes of gastric juice, discharging level of pepsin, inhibiting effects of ulceration, and transporting of intestine. Methods : Sample I : No making Strychni Ignatii Semen Sample II : Depositing for three days in water and then dry it. Sample III : Depositing for one hour in sesame oil and bum it. The results were as follows : 1. The average values of Strychnine decreased in Sample III. 2. The levels of $LD_{50}$ increased in Sample Ⅲ by about 70%. 3. In Sample III, inhibiting effects of ulceration and discharging level of pepsin were great. 4. In the level of gastric juice decreased in Sample I.II.III. 5. The transporting ability of large intestine elevated in Sample I.II.III. According to the results, making Strychni Ignatii Semen, especially Sample 3, toxicity decreased and has good effects on the gastrointestinal system.

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Relationship between Gastric Motility and Health Condition Graded by Total Symptom Scores in Comprehensive Diagnosis of Qui Xue Shui in Functional Dyspeptic Patients (기능성 소화불량증 환자의 변증증후(辨證證候)에 의한 건강상태와 위 운동성의 상관성에 대한 연구 (기혈수(氣血水) 변증(辨證)과 위전도 지표를 중심으로))

  • Jeong, Ha-Deok;Kim, Jin-Sung;Ryu, Bong-Ha;Ryu, Ki-Won;Yoon, Sang-Hyub
    • The Journal of Internal Korean Medicine
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    • v.25 no.4
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    • pp.158-166
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    • 2004
  • Background & Object : The aim of this study was to investigate the usefulness of electrogastrography in the diagnosis field of traditional medicine through a study of the relationship between gastric motility and health condition based on oriental medicine diagnostic theory in functional dyspepsia. Method : 86 patients (male 27, female 59) with functional dyspepsia and 10 healthy control subjects (male 5, female 5) were involved in the investigation. The disease information of functional dyspepsia (based on Rome criteria II) was used for dyspeptic index and scores were obtained from the comprehensive diagnosis of Qui, Xue, Shui was applied as index for health condition, those were all investigated by questionnaire. Gastric motility were recorded and analyzed using electrogastrography in fasting and postprandial period. Results : The total score of comprehensive diagnosis of Qui Xue Shui was influenced by the number of functional dyspepsia symptoms (p=0.026). In terms of electrogastrographical parameters, both postpranial normal slow waves regularity(p=0.003) and power ratio (p=0.001) in the patients had the statistical significance and they showed an incremental inverse correlation with the number of symptoms. Dominant frequency and fasting normal slow waves regularity ratio had no statistical significance. Conclusion : Results suggest that electrogastrography is useful in evaluating the health condition of patient by comprehensive diagnosis of Qui Xue Sui.

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