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Improving Corsican pine somatic embryo maturation: comparison of somatic and zygotic embryo morphology and germination

  • Wtpsk, Senarath;Shaw, D.S.;Lee, Kui-Jae;Lee, Wang-Hyu
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2003.04a
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    • pp.61-62
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    • 2003
  • Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

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'Joseong', a New Early-Heading Forage Triticale Cultivar for Paddy Field of Double Cropping (이모작 재배에 적합한 조숙성 조사료용 트리티케일 신품종 '조성')

  • Han, Ouk-Kyu;Park, Tae-Il;Park, Hyung-Ho;Song, Tae-Hwa;Ju, Jung-Il;Jeung, Jae-Hyun;Kang, Sung-Joo;Kim, Dae-Ho;Choi, Hong-Jib;Park, Nam-Geon;Kim, Kee-Jong;Hwang, Jong-Jin;Baek, Seong-Beum;Kwon, Young-Up
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.32 no.3
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    • pp.193-202
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    • 2012
  • 'Joseong', a winter forage triticale cultivar (X Triticosecale Wittmack), was developed by the breeding team at the Department of Rice and Winter Cereal Crop, NICS, RDA in 2010. The cultivar 'Joseong' was selected from the cross FAHAD_5/RHINO1R.1D 5+10 5D'5B'//FAHAD_5 by CIMMYT (Mexico) in 1992. Subsequent generations were handled in pedigree selection program at Mexico from 1993 to 1998, and a line 'CTSS92Y-A-4Y-0M-5Y-0B' was selected for earliness and good agronomic characteristics. After preliminary and advance yield test in Korea for 2 years, the line designated as a line name of 'Iksan26'. The 'Iksan26' was subsequently evaluated for earliness and forage yield in 7 different locations such as Jeju, Iksan, Cheongwon, Yesan, Naju, Daegu, and Jinju from 2008 to 2010 and finally named as 'Joseong'. The cultivar 'Joseong' has characteristics of dark green leaf, yellow culm and spike, and large grain of yellowish brown color. The heading date of cultivar 'Joseong' was April 24, which was 5 days earlier than that of check cultivar 'Shinyoung'. It showed better tolerance or resistance to lodging, wet injury, powdery mildew, and leaf rust than those of the check cultivar 'Shinyoung'. The average forage dry matter yield of cultivar 'Joseong' at milk-ripe stage was 14.5 MT $ha^{-1}$, which was lower than 16.5 MT $ha^{-1}$ of the check cultivar 'Shinyoung'. The silage quality of 'Joseong' (5.3%) was lower to the check cultivar 'Shinyoung' (6.0%) in crude protein content, while was 2.1% superior to the check cultivar 'Shinyoung' (61.9%) in TDN (total digestible nutrients). It showed 5.1 MT $ha^{-1}$ of grain yield, which was 40% higher than that of the check cultivar 'Shinyoung' (3.65 MT $ha^{-1}$). This cultivar is recommended for fall sowing crop in the area where daily minimum mean temperatures are averaged higher than $-10^{\circ}C$ in January, and as a winter crop using whole crop forage before planting rice in around Korea.

The Utility of Measurement of Plasma N-terminal Pro-brain Natriuretic Peptide in Diagnosis of Pulmonary Hypertension (폐동맥고혈압 진단에 있어 N-terminal Pro-brain Natriuretic Peptide 측정의 유용성)

  • Hahn, Chang Hoon;Kang, Seok Min;Moon, Jin Wook;Cho, Jae Hee;Hwang, Sang Yon;Lee, Jung Min;Park, Moo Suk;Chung, Jae Ho;Kim, Young Sam;Kim, Se Kyu;Chang, Joon;Shim, Won Heum;Kim, Sung Kyu
    • Tuberculosis and Respiratory Diseases
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    • v.56 no.1
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    • pp.67-76
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    • 2004
  • Background : Pulmonary hypertension is a poor prognostic factor in patients with chronic respiratory disease. However, diagnosing pulmonary hypertension is a difficult procedure which often requires an invasive test. Thus new alternative biochemical markers would be useful in clinical field and are in search. We sought to assess the role of plasma N-terminal pro-brain natriuretic peptide(NT-proBNP) in patients with pulmonary hypertension. Method : We measured plasma NT-proBNP level in twenty nine patients suspected for pulmonary hypertension. Pulmonary hypertension was defined as being right ventricular systolic pressure more than 35 mm Hg estimated by Doppler echocardiography. Plasma NT-proBNP level was measured by electrochemiluminescence sandwich immunoassay. Results : The log-transformed values for plasma NT-proBNP levels showed a linear correlation (correlation coefficiency: 0.783, p-value <0.001) with right ventricular systolic pressure. Plasma NT-proBNP levels closely correlated with right ventricular systolic pressure, right ventricular hypertrophy, interventricular septal flattening and right ventricular dilatation. Conclusion : Our results suggest that the measurement of plasma NT-proBNP level is an useful marker of the presence of pulmonary hypertension.

PREPARATION OF AMORPHOUS CARBON NITRIDE FILMS AND DLC FILMS BY SHIELDED ARC ION PLATING AND THEIR TRIBOLOGICAL PROPERTIES

  • Takai, Osamu
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2000.11a
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    • pp.3-4
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    • 2000
  • Many researchers are interested in the synthesis and characterization of carbon nitride and diamond-like carbon (DLq because they show excellent mechanical properties such as low friction and high wear resistance and excellent electrical properties such as controllable electical resistivity and good field electron emission. We have deposited amorphous carbon nitride (a-C:N) thin films and DLC thin films by shielded arc ion plating (SAIP) and evaluated the structural and tribological properties. The application of appropriate negative bias on substrates is effective to increase the film hardness and wear resistance. This paper reports on the deposition and tribological OLC films in relation to the substrate bias voltage (Vs). films are compared with those of the OLC films. A high purity sintered graphite target was mounted on a cathode as a carbon source. Nitrogen or argon was introduced into a deposition chamber through each mass flow controller. After the initiation of an arc plasma at 60 A and 1 Pa, the target surface was heated and evaporated by the plasma. Carbon atoms and clusters evaporated from the target were ionized partially and reacted with activated nitrogen species, and a carbon nitride film was deposited onto a Si (100) substrate when we used nitrogen as a reactant gas. The surface of the growing film also reacted with activated nitrogen species. Carbon macropartic1es (0.1 -100 maicro-m) evaporated from the target at the same time were not ionized and did not react fully with nitrogen species. These macroparticles interfered with the formation of the carbon nitride film. Therefore we set a shielding plate made of stainless steel between the target and the substrate to trap the macropartic1es. This shielding method is very effective to prepare smooth a-CN films. We, therefore, call this method "shielded arc ion plating (SAIP)". For the deposition of DLC films we used argon instead of nitrogen. Films of about 150 nm in thickness were deposited onto Si substrates. Their structures, chemical compositions and chemical bonding states were analyzed by using X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy and infrared spectroscopy. Hardness of the films was measured with a nanointender interfaced with an atomic force microscope (AFM). A Berkovich-type diamond tip whose radius was less than 100 nm was used for the measurement. A force-displacement curve of each film was measured at a peak load force of 250 maicro-N. Load, hold and unload times for each indentation were 2.5, 0 and 2.5 s, respectively. Hardness of each film was determined from five force-displacement curves. Wear resistance of the films was analyzed as follows. First, each film surface was scanned with the diamond tip at a constant load force of 20 maicro-N. The tip scanning was repeated 30 times in a 1 urn-square region with 512 lines at a scanning rate of 2 um/ s. After this tip-scanning, the film surface was observed in the AFM mode at a constant force of 5 maicro-N with the same Berkovich-type tip. The hardness of a-CN films was less dependent on Vs. The hardness of the film deposited at Vs=O V in a nitrogen plasma was about 10 GPa and almost similar to that of Si. It slightly increased to 12 - 15 GPa when a bias voltage of -100 - -500 V was applied to the substrate with showing its maximum at Vs=-300 V. The film deposited at Vs=O V was least wear resistant which was consistent with its lowest hardness. The biased films became more wear resistant. Particularly the film deposited at Vs=-300 V showed remarkable wear resistance. Its wear depth was too shallow to be measured with AFM. On the other hand, the DLC film, deposited at Vs=-l00 V in an argon plasma, whose hardness was 35 GPa was obviously worn under the same wear test conditions. The a-C:N films show higher wear resistance than DLC films and are useful for wear resistant coatings on various mechanical and electronic parts.nic parts.

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A Study on the Outlook of Dentists on Dental Coordinators and Their Job (치과의사의 치과 코디네이터 업무 및 인식에 관한 조사연구)

  • Yoo, Jung-Sook;Jang, Mi-Hwa;Jung, Jae-Yeon;Cho, Myung-Sook;Choi, Bu-Geun;Hwang, Yoon-Sook
    • Journal of Korean society of Dental Hygiene
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    • v.5 no.2
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    • pp.201-218
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    • 2005
  • The purpose of this study was to examine how dentists perceived dental coordinators including their education, hiring criteria, working condition and job. It's basically attempted to help define the job and role of 5 and to suggest how they should be nurtured. The subjects in this study were dentists at dental hospitals and clinics where dental coordinators were employed among approximately 200 dental institutions in Seoul, Cyeonggi province and Incheon. After a survey was conducted in June 2005, answer sheets from 99 respondents were analyzed. The findings of the study were as follows: 1. Regarding education for dental coordinators, 99.9% of the dentists investigated felt the need for separate education programs for dental coordinators, 42.4% knew what would-be dental coordinators learned about, and 81.8% considered it necessary for them to take intermediate or higher courses. An organization affiliated with the Korea Dental Hygienists Association was viewed as the best institute to educate dental coordinators, and educational institutes that included a department of dental hygiene was looked upon as the second best one. 68.7% believed that dental coordinators should take an official examination to test their qualifications, and concerning educational subsidy, the largest group of the dentists thought that a certain amount of subsidy should be provided. 2. As for coordinator hiring, the top priority was the impression(look) of applicants(55%), followed by adjustability to existing employees(24.5%) and professional competency(17.3%). As to the route of hiring, 41.4 percent, the largest group, reeducated some of existing employees, and dental hygienists were regarded as the best personnels to serve as a coordinator. Concerning job performance, they put the most emphasis on interpersonal relationship, which was followed by executive ability, impression and career, 58.6% the largest group, believed that dental coordinators should have a three-year or higher career to work at a dental institute. 3. As to working conditions, 75.7%, the largest group, paid dental coordinators based on their job performance, and 23.2%, the second largest group, had their pay equal to that of dental hygienists, 88.9% allowed them to determine their own retirement age. 4. In regard to their perception of dental coordinators, the largest number of the dentists considered it necessary for them to keep receiving education(4.29), and the second largest group felt that they served to enhance the image of dental institutes(4.18). The third largest group thought that they contributed to letting patients more satisfied with the quality of dental services. But they tended not to agree that their turnover rate was low(3.04), and they didn't find them to receive appropriate education, either(3.10). 5. The current major job of coordinators associated with customer services was handling appointments with customers(91.9%), treating unsatisfied customers(85.9%), and controling waiting time(84.8%). Regarding self-management, coordinators directed their energy into having good manners(89.9%), acquiring fundamental dental knowledge(84.8%), and learning how to treat customers(83.8%). Concerning hospital affairs handling, they were most responsible for information desk(87.9%), which was followed by receiving(86.9%). As a result of investigating what type of job the dentists hoped dental coordinators to fulfill in consideration of their career, their age and type of investment, the dentists wanted them the most to speak a foreign language, which belonged to the field of self-management.

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The dose distribution and DVH change analysis wing to effect of the patient setup error (환자 SET-UP ERROR에 따른 선량분포와 DVH 변화 분석)

  • Kim KyoungTae;Ju SangGyu;Ahn JaeHong;Park YoungHwan
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.2
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    • pp.81-89
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    • 2004
  • Introduction : The setup error due to the patient and the staff from radiation treatment as the reason which is important the treatment record could be decided is a possibility of effect. The SET-UP ERROR of the patient analyzes the effect of dose distribution and DVH from radiation treatment of the patient. Material & Methode : This test uses human phantom and when C-T scan doing, It rotated the Left direction of the human phantom and it made SET-UP ERROR , Standard plan and 3mm, 5mm, 7mm, 10mm, 15mm, 20mm with to distinguish, it made the C-T scan error. With the result, The SET-UP ERROR got each C-T image Using RTP equipment It used the plan which is used generally from clinical - Box plan, 3Dimension plan( identical angle 5beam plan) Also, ( CTV+1cm margin, CTV+0.5cm margin, CTV+0.3,cm margin = PTV) it distinguished the standard plan and each set-up error plan and The plan used a dose distribution and the DVH and it analyzed Result : The Box4 the plan and 3Dimension plan which it bites it got similar an dose distribution and DVH in 3mm, 5mm From rotation error and Rectilinear movement( $0\%{\sim}2\%$ ). Rotation error and rectilinear error 7mm, 10mm, 15mm, 20mm appeared effect it will go mad to a enough change in treatment ( $2\%{\sim}^11\%$ ) Conclusion : The diminishes the effect of the SET-UP ERROR must reduce move with tension of the patient Also, we are important accessory development and the supply that it reducing of reproducibility and the move

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A SURVEY ON THE USE OF COMPOSITE RESIN IN CLASS II RESTORATION IN KOREA (2급 와동 수복 시 한국 치과 지사들의 복합레진 사용 실태 연구)

  • Shin, Dong-Ho;Park, Se-Eun;Yang, In-Seok;Chang, Ju-Hea;Lee, In-Bog;Cho, Byeong-Hoon;Son, Ho-Hyun
    • Restorative Dentistry and Endodontics
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    • v.34 no.2
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    • pp.87-94
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    • 2009
  • The purpose of this study was to assess the current materials, methods and difficulties according to the year of licence and educational background of Korean dentists in Class II direct composite resin restorations. Total 17 questions were included in the questionnaire. Questions were broadly divided into two parts: first. operator's information. and second. the materials and methods used in Class II posterior composite restoration. The questionnaire was sent to dentists enrolled in Korean Dental Association via e-mail. Total 12,193 e-mails were distributed to dentists. 2,612 e-mails were opened, and 840 mails (32.2%) were received from respondents. The data was statically analyzed by chi-square test using SPSS(v. 12.0.1, SPSS Inc. Chicago, IL, USA). Male dentists among respondents was 79%. 60.3% of the respondents acquired their licences recently (1998-2007), and 77% practiced in private offices. 83.4% have acquired their knowledge through school lectures, conferences and seminars. For the Class II restorations, gold inlays were preferred by 65.7% of respondents, while direct composite resin restorations were used by 12.1 % amalgam users were only 4.4% of respondents. For the restorative technique, 74.4% of respondents didn't use rubber dam as needed. For the matrix. mylar strip (53.4%), metal matrix (33.8%) and Palodent system (6.5%) were used. 99.6% of respondents restored the Class II cavity by incremental layering. Obtaining of the tight interproximal contact was considered as the most difficult procedure (57.2%) followed by field isolation (21 %). Among various bonding systems, 22.6% of respondents preferred SE Bond and 20.2% used Single Bond. Z-250 was used most frequently among a variety of composite resins.

A Study on the Factors Affecting the Success of Technology Marketing (기술마케팅 성공에 영향을 미치는 요인에 관한 분석)

  • Hwang, Nam-Gu;Oh, Young-Ho;Kim, Kyoung-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.7
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    • pp.2358-2370
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    • 2010
  • This research aims to empirically analyze the factors that affect the success of technology marketing by Korean universities. The total of 207 universities which successfully made technology transfers from 2006 to 2008 was examined to test the nine hypotheses. For the purpose of testing the hypotheses, technology infrastructure (research costs and the number of SCIE papers), the compensation system for the patents (application and registration), the number of patents (application and registration), TLO staff (the number of people in charge of technology transfer and the job experience in industries), the compensation system for technology transfers (researchers and contributors), and attitudes of university management and industries were analyzed with structural equation methods to figure out their effects on the revenues of technology transfer. The results of this research are summarized as follows. First, technology infrastructures of universities were found to have positive effects on securing patents. As the university research costs in the field of science and technology are increases, the research capabilities are enhanced and this a larger number of researchers are conducted. Second, this research shows that compensation systems for patent application and registration in universities have motivated researchers to take out patents for the outputs of their research. Third, the number of patents universities possess was found to have a positive effect on technology transfer. An increase in the number of patents universities possess implies an increase in the diversity and excellence of the target technologies for transfer. Fourth, the number of patents universities possess turned out to have a positive effect on TLO staff. The number of experts in charge of technology transfer including technology dealers, valuation analysis and patent attorneys should be increased as target technologies for transfer increase according to the increase of patents possessed. Because the technologies are transferee from universities to businesses, businesses (job) experience of TLO staff in industries are also important. This research is meaningful because it has identified the factors affecting the results of technology transfer by employing structural equation methods. In particular, an official governmental survey data for the academic-industrial cooperation were analyzed systematically in terms of technology infrastructure, compensation systems related to patents, the number of patents, TLO staff, compensation systems for technology transfer, and attitudes of university management and industries. All these facts might could differentiate this study from the previous studies.

Relationship between XRCC1 Polymorphism and Acute Complication of Chemoradiation Therapy in the Patients with Colorectal Cancer (대장, 직장암 환자에서 화학방사선치료의 급성 부작용과 XRCC1 유전자 다형성과의 상관관계)

  • Kim Woo-Chul;Hong Yun-Chul;Choi Sun-Keun;Woo Ze-Hong;Nam Jeong-Hyun;Choi Gwang-Seong;Lee Moon-Hee;Kim Soon-Ki;Song Sun-U.;Loh John-Jk
    • Radiation Oncology Journal
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    • v.24 no.1
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    • pp.30-36
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    • 2006
  • Purpose: It is well known from clinical experience that acute complications of chemoradiation therapy vary from patients to patients. However, there are no known factors to predict these acute complications before treatment starts. The human XRCC1 gene is known as a DNA base excision repair gene. We investigated the possibilities of XRCC1 gene polymorphisms as a predictor for the acute complications of chemoradiation therapy in colorectal cancer patients. Materials and Methods: From July 1997 to June 2003, 86 colorectal cancer patients (71 rectal cancer, 13 sigmoid colon cancer and 2 colon cancer patients) were treated with chemoradiation therapy at the Department of Radiation Oncology, Inha University Hospital. Twenty-two patients were in stage B, 50 were in stage C, 8 were in stage D and 6 patients were unresectable cases. External radiation therapy was delivered with 10MV X-ray at a 1.8 Gy fraction per day for a total dose of radiation of $30.6{\sim}59.4 Gy$ (median: 54 Gy). All the patients received 5-FU based chemotherapy regimen. We analyzed the acute complications of upper and lower gastrointestinal tract based on the RTOG complication scale. The initial and lowest WBC and platelet count were recorded during both the RT period and the whole treatment period. Allelic variants of the XRCC1 gene at codons 194, 280 and 399 were analyzed in the lymphocyte DNA by performing PCR-RFLP. Statistical analyses were carried out with the SAS (version 6.12) statistical package. Results: When all the variables were assessed on the multivariate analysis, recurrent disease revealed the factors that significantly correlated with upper gastrointestinal acute complications. Arg399Gln polymorph isms of the XRCC1 gene, the radiation dose and the frequencies of chemotherapy during radiation therapy were significantly correlated with lower gastrointestinal complications. Arg399Gln polymorph isms also affected the decrease of the WBC and platelet count during radiation therapy. Conclusion: Although the present sample size was too small for fully evaluating this hypothesis, this study suggests that Arg399Gln polymorph isms of the XRCC1 genes may be used as one of the predictors for acute complications of chemoradiation therapy in colorectal cancer patients.

Effect of top dressing of Compound Fertilizer Containing nitrate (Ammonium Nitrate Sulfate) on Paddy Rice (수도용(水稻用) 질산태질소함유(窒酸態窒素含有) 복합비료(複合肥料)의 추비효과(追肥效果))

  • Kim, Jeong-Je;Jang, Yong-Seon;Cho, Byong-Ok;Huh, Beom-Lyang
    • Korean Journal of Soil Science and Fertilizer
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    • v.21 no.3
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    • pp.289-295
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    • 1988
  • An ordinary paddy variety Hwaseong and a high-yielding variety Samgang were taken under investigation to test the effect of top dressing of newly formulated three compound fertilizers on rice plants for at sprouting heads. The fertilizer formulate used were C. F. I (14-0-14; $NO_3-N$ and $NH_4-N$) and C. F. II (14-0-14; $NH_4-N$ only) and C. F. III (14-0-14 + OM 10%; $NO_3-N$ and $NH_4-N$). A field experiment was conducted on a plot of Gyuam series. The following results were obtained: 1. Effects of compound fertilizers at sprouting heads a. Hwaseong variety exhibited 5-10% yielding increases on the plots with application of 2nd compound fertilizer (I) and (II) compared to straight fertilizer of (I) and (III). Fertilization with 2nd and 3rd compound fertilizers gave the best result when they are done 15 days before heading. A yield increase of 3-5% was achieved when the fertilization was done 20 days before heading in the case of Samgang variety, but no beneficial effect was observed with an application 10 days before heading. b. Rate of barren grains was at the minimum in the compound fertilizer (II) plots of both Hwaseong and Samgang varieties. c. Content of $NO_3-N$ in soils and grain yield appeared to be positively correlated($r=0.618^*$) 2. Effects of heading fertilizers on artificially reduced conditions of soil a. No significant difference in Eh values were measured among reduced paddy soils. The compound fertilizer of (II) presented the best result in yield increases regardless of rice variety. b. Rate of barren grains in both varieties was observed at the minimum on the application of compound fertilizer of (II). c. No great difference of mineral contents was detected among plants from different treatments.

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