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Henoch-$Sch{\ddot{o}}nlein$ Nephritis in Children (소아 Henoch-$Sch{\ddot{o}}nlein$ 신염의 추적 관찰)

  • Jang, Hee-Suk;Hong, In-Hee;Go, Cheol-Woo;Koo, Ja-Hun;Kwak, Jung-Sik
    • Childhood Kidney Diseases
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    • v.4 no.2
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    • pp.120-126
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    • 2000
  • Purpose : This retrospective study has been undertaken to find out the clinical outcome of children with HS nephntis and its relationship with initial clinical presentation and/or renal pathologic finding. Patients and methods : Study population consisted of 59 children with HS nephritis who have been admitted to the Pediatric department of Kyungpook University Hospital from 1987 to 1999, and biopsy was done with indications of heavy proteinuria (> 1 g/m2/day) lasting over 1 month, nephrotic syndrome, and persistent hematuria and/or proteinuria over 1 year. Patients were divided clinically into 3 groups ; isolated hematuria, hematuria with proteinuria and heavy proteinuria (including nephrotic syndrome). Biopsy findings ore graded from I-V according to International Study of Kidney Disease in Children (ISKDC). Results : Mean age of presentation was $8.1{\pm}3.0$ years and slight male preponderance m noted (33 boys md 26 girls). Histopathologic grading showed Grade I ; 2, Grade II ; 44, and Grade III ; 13 cases. Clinical outcome at the follow-up period of 1-2 year (49 cases) and 3-4 years (30 cases) shooed normal urinalysis in 75 (30.6$\%$) and 18 cases (60.0$\%$), persistent isolated hematuria in 20 (40.8$\%$) and 2 cases (6.7$\%$), hematuria with proteinuria in 11 (22.5$\%$) and 8 cases (26.6$\%$), and persistent heavy proteinuria in 3 (6.1$\%$) and 2 cases (6.7$\%$) respectively. Clinical outcome according to histopathologic grading showed the frequency of normalization of urinalysis being lower in Grade III compared to grade I or II. Clinical outcome according to initial clinical presentation showed no relationship to the normalization or urinalysis at follow-up periods. However, 15-20$\%$ of children with initial heavy proteinuria showed persistent heavy proteinuria (3 out of 20 cases at 1-2 years, and 2 out of 10 case at 3-4 years of follow-up periods). Conclusion : The majority of children with HS nephritis (histopathologic grade I, II, III) improved within 3-4 years and persistent heavy proteinuria was seen only in a kw of children with initial clinical presentation of heavy proteinuria.

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Comparison of Functional Materials in Organic Cultivated Minor Cereal Crops (유기농 잡곡의 몇몇 기능성 물질 비교)

  • Yoon, Seong-Tak;Kim, Tae-Ho;Nam, Jung-Chang;Kim, Tae-Yun;Kim, Hye-Rim;Jo, Sung-Hoon;Lee, Seung-Woo;Lee, Myung-Cheol;Kim, Min-Jeong;Kim, Seong-Min
    • Korean Journal of Organic Agriculture
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    • v.20 no.4
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    • pp.619-630
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    • 2012
  • Miscellaneous grain crops has been appeared as a well-being food and the demand of them are increasing recently. It is urgent to study especially about the functional materials of foxtail millet, common millet and sorghum. This experiment was conducted to evaluation and comparison several functional materials of fatty acids, anthocyanin content, total phenol content and DPPH assay of rice, and foxtail millet, common millet and sorghum produced organically so that these results would provide as a basic information for developing functional products by using miscellaneous grain crops. Total content of fatty acids was in order of foxtail millet (0.649%) and common millet (0.33%), sorghum (0.172%) and rice (0.111%) respectively. The content of unsaturated fatty acid was also in order of foxtail millet (0.511%) and common millet (0.269%), sorghum (0.122%) and rice (0.069%) respectively. Although there was no detection of anthocyanin content in rice, foxtail millet and common millet, sorghum showed high content of anthocyanin content. Sorghum of Mongdangsusu showed the highest anthocyanin content (137.5mg/g). In the total phenol content of rice, foxtail millet, common millet and sorghum, rice of Chucheongbyeo had high content ($13.70{\mu}g/g$) whereas Daeanbyeo was the lowest content ($10.07{\mu}g/g$). Foxtail millet of Hinchajo, common millet of Byeorukgijang and sorghum of Chalsusu showed the highest total phenol content of $25.8{\mu}g/g$, $69.4{\mu}g/g$ and $682.2{\mu}g/g$ respectively. In the average of total phenol content among rice, foxtail millet, common millet and sorghum, foxtail millet, common millet and sorghum showed $12.25{\mu}g/g$, $16.95{\mu}g/g$, $51.01{\mu}g/g$ and $447.4{\mu}g/g$ of total phenol content respectively. The average of total phenol content of sorghum was $26.3{\mu}g/g$. It is 36.3 and 26.3 times higher compared with rice and foxtail millet respectively. In the antioxidant activity of seeds by DPPH(1,1-diphenyl-2-picrylhydrazyl) assay for rice, foxtail millet, common millet and sorghum, rice of Chucheongbyeo, foxtail millet of Ganghywajo and common millet of Geumeungijang showed the highest antioxidant activity with 3.6%, 4.78% and 13.4% respectively. Antioxidant activity of sorghum ranged from 88.47 to 90.11%. The average of antioxidant activity among four crops, the highest antioxidant activity was obtained from sorghum (89.50%) and the next was common millet (6.13%), foxtail millet (2.43%), and rice (1.60%) in their order of antioxidant activity. The average of antioxidant activity of sorghum showed 55.9, 37.0 and 15times higher compared with rice, common millet and foxtail millet respectively.

The Effects of Environment-Friendly Agricultural Materials on Soil and the Quality of 'Niitaka' pear's Orchad (친환경농자재 처리가 배과수원 토양 및 과실품질에 미치는 영향)

  • Yoon, Seong-Tak;Xu, Zhen-Yu;Zhang, Qing-Yu;Kim, Tae-Ho;Nam, Jung-Chang;Park, Sang-Hun;Kwak, No-Il;Mun, Su-Hak;Lee, Hyuk-Jae;Choi, Jin-Ho
    • Korean Journal of Organic Agriculture
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    • v.18 no.4
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    • pp.613-626
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    • 2010
  • Coming with the well-being era, consumer's demand for safe agricultural products is increasing. It is urgent to develop an environment-friendly pear production system. Accordingly, this study was conducted to develop an environment-friendly pear production system by using several environment-friendly agricultural materials which is known to be effective in agricultural production. In the effects of environment-friendly agricultural materials on the soil chemical characteristics in pear orchard, the content of total carbon, organic matter, Ca and Mg increased a little respectively compared with those of 2008, and 2nd treatment showed the highest EC and Mg content in the soil among treatments. The content of leaf N, P and Ca in 2009 decreased compared with those of 2008, while Mg content showed no difference between 2008 and 2009 years. Average pear weight in 2009 was 31g higher than that of 2008 (682g) and 2nd treatment showed the highest pear weight (738g) among treatments. The average sugar content was higher in 2009 (12.6$^{\circ}Bx$) compared with that of 2008 (12.2$^{\circ}Bx$) and the plot of 2nd treatment highest sugar content (12.6$^{\circ}Bx$) among treatments. There were no difference in hunter value of L among treatments, but hunter value of a showed higher 1.62 in 2009 than that of 2008 (3.73). The highest of gumminess and cohesiveness of fruits were obtained from 1st treatment and adhesiveness and chewiness of fruits were obtained from 3rd and 1st treatment respectively. Firmness of fruit increased a little in 2009 compared with that of 2008, while the highest firmness was obtained from 3rd treatment with 1.63kg/5mm$\oint$ among treatments. Phosphate content in the peel of 'Niitaka' pear of fruit skin in 2009 (0.97g/kg) showed 0.06g/kg more content than that of 2008 (0.91g/kg), while the highest content was obtained from 3rd treatment (1.15g/kg). Potassium content in the peel of 'Niitaka' pear in 2009 was 8.20g/kg, which is 0.06g/kg more content than that of 2008 (7.82g/kg) and the highest content was obtained from 1st treatment (8.34g/kg) among treatments. The highest nitrogen content in the flesh of 'Niitaka' pear was obtained from 3rd treatment (4.32mg/g), while it was the lowest in control plot (3.10mg/g). Phosphate content in the flesh of 'Niitaka' pear in 2009 (8.20g/kg) showed 0.06g/kg more content than that of 2008 (7.82g/kg), while the highest content was obtained from 1st treatment (8.34g/kg). There were no difference of the potassium content in the fruit peel of 'Niitaka' pear between years, but 1st treatment showed the highest content (11.81g/kg) among treatments, while the lowest was obtained from the control plot (10.83g/kg).

Weeding Effect and Phytotoxicity Variable in Herbicide Treatment in Mechanically Transplanted Paddy Field - 1. Effect of Application Time on Weeding Effect and Phytotoxicity (기계이앙답에(機械移秧畓) 있어서 제초제(除草劑)의 약효(藥效) 및 약해(藥害) 변동요인(變動要因) - 제(第) 1 보(報) 처리시기(處理時期)의 차이(差異)가 약효(藥效) 및 약해(藥害)에 미치는 영향(影響))

  • Ryang, Hwan-Seung;Han, Seong-Soo;Kim, J.S.
    • Korean Journal of Weed Science
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    • v.1 no.1
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    • pp.69-77
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    • 1981
  • Six herbicides were evaluated to investigate the phytotoxicity of rice plant and the weeding efficacy influenced by the time of application in mechically transplanted paddy field. The amount of each chemical applied was 3 kg, a. i, /ha. Chlormethoxynil : Rotala indica KOEHNE and Lindernia pyxuiaria PHILCOX were effectively controlled when applied on the 12th day after transplanting (12 DAT) and this herbicide was excellent for the control of Echinochloa crusgalli P. BEAUV, Monochoria vaginalis PRESL and Sagittaria pygmaea MIQ, when applied early (7 days after puddling) but its weeding effect for these weeds decreased greatly as the application time became later. It had a controlling effect for Potamogeton distinctus A. BENN, Cyperus serotinus ROTTB and Scirpus hotarui ROXB at the initial period at the earlier application time. Butachlor was effective in controlling E. crusgalli, R. indica and L. pyxidaria at 12 days after transplanting (DAT) but was not effective in controlling P. distinctus and S. pygmaea even at the early application time. M. vaginalis, C. serotinus and S. hotarui were effectively controlled by the butachlor treatment at 7 days after final puddling (2 DBT-SDAT) but this weeding effect decreased at the late application time. A combination of butachlor and naproanilide excellently controlled E. crusgalli, R. indica, L. pyxidaria and S. pygmaea regardless of the application time. For the control of M. vaginalis, C. serotinus and P. distinctus, the weeding effect of this mixtures was much greater than that of the single treatment of butachlor. Perfluidone was excellent for the control of E. crusgalli, R. indica, L. pyxidaria, M. vaginalis and S. pygmaea at either application time tested. P. distinctus, C. serorinus and S. hotarui could be controlled by this chemicals until the time of first observation (23 DAT) but the effect for these weeds somewhat decreased as time passed. The effect of pyrazolate on E. crusgalli, M. vaginalis, S. hotarui and P. distinctus was very excellent regardless of the application time but R. indica and L. pyxidaria could not be completely eliminated by this chemical. This chemical was effective in controlling C. serotinus when applied at 7-9 days after final puddling and showed a controlling effect for S. hotaruionly at the initial period. Piperophos + dimethametryn was very excellent for the control of all the annual weeds and P. distinctus. It showed a controlling effect on S. pygmaea, C. serotinus and S. hotarui only at the initial period. There was no difference in the effects on phytotoxicity and yield between chlormethoxynil and pyrazolate at either times of application tested. The later the application time was, the less the phytotoxicity of butachlor and piperophos+dimethametryne was. The phytotoxicity of butachlor + naproanilide and perfluidone decrease in the plots treated at the later application time. When the last two chemicals were treated at 2 days before transplanting (DBT) the yield decreased as compared with the hand weeded plot.

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The Evaluation of Factors Which Influence Binding Efficiency of Modified in Vivo Erythrocyte Labeling Technique (변형 체내 표지법에 의한 적혈구 표지시 결합효율에 영향을 미치는 인자 평가)

  • Seo, Han-Kyung;Kim, Min-Woo;Lim, Seok-Tae;Sohn, Myung-Hee
    • The Korean Journal of Nuclear Medicine
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    • v.38 no.4
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    • pp.300-305
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    • 2004
  • Purpose: We underwent this study to evaluate the factors which influence labeling efficiency when modified in vivo erythrocyte labeling technique was used. Materials and methods: Thirty healthy volunteers (M:F=19:11, age:$25{\pm}2$ yrs) were enrolled in this study. Totally, two hundred ten samples were obtained from them. The 1 mg of stannous pyrophosphate was injected intravenously at the beginning of labeling. After suitable tinning time (5 min, 20 min, 35 min) passed by, blood (5 mL, 3 mL or 1 mL) was withdrawn into 10 mL syringe previously containing Tc-99m (740 MBq) and anticoagulant (heparin, ACD or CPDA) through 19-gauged scalp needle. The generator ingrowth time of Tc-99m was within 24 hrs in each case. The blood samples were placed on rotating invertor during incubation (10 min, 25 min, 40 min) but some of them were not. Immediately after the conclusion of incubation, the labeled blood specimens to analyze were centrifuged. and then %Unbound Tc-99m was calculated. Statical analysis was used paired T-test and one way ANOVA with SPSS 10.0. Results: The binding efficiency at 1 mL of blood volume was $73{\pm}32%,\;91{\pm}10%$ at 3 mL and $96{\pm}7%$ at 5 mL (p<0.01). The binding efficiency at 5 min of tinning time was $45{\pm}23%,\;98{\pm}6%$, at 20 min and $97{\pm}8%$ at 35 min (p<0.001). The binding efficiency at 10 min of incubation time was $96{\pm}7%,\;95{\pm}12%$ at 25 min and $98{\pm}3%$ at 40 min (p>0.05). The binding efficiency in case of using rotating invertor was $96{\pm}7%$ and the binding efficiency in case of not using it was $87{\pm}18%$ (p>0.05). There was no significant difference between them. In binding efficiency according to kinds of anticoagulants, ACD was $98{\pm}4%$, CPDA was $97{\pm}6%$ and heparin was $89{\pm}20%$ (p<0.001). Conclusion: When modified in vivo erythrocyte labeling technique is used with Tc-99m, the methods to obtain the highest labeling efficiency are as follow. The withdrawing blood volume should be over 3 mL, tinning time should be kept between 20 min and 35 min, and incubation time should be kept between 10 min and 40 min. ACD or CPDA have to be used as a anticoagulant except heparin and the blood samples should be placed on rotating invertor during incubation.

The study of food habit and degree of depression in nursing home and privite home living elderly (시설노인과 재가노인의 식습관과 정신건강 상태에 관한 실태조사)

  • Han, Myung-Joo;Koo, Sung-Ja;Lee, Young-Soon
    • Journal of the Korean Society of Food Culture
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    • v.13 no.5
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    • pp.475-486
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    • 1998
  • The dietary habit, health condition and the cognition concerning the health food have been surveyed with the help of the 151 old people living in In-Cheon and Seoul. In this study, the old are classified as an institution for the aged and the old in their own home. The preference and mental health condition influenced on dietary habits have been surveyed as wall. Their dietary habits such s three meals a day and a regular meal time have show) that they have generally good eating habits. Psychologically, the old in an institution for the aged think their health condition is not so good in comparison with the old in their own home. The old in their own home have good condition in that they can go up the stairs, exercise often and walk relatively well. Moreover, men's health condition is better than women. The old generally like meats(especially beef) and prefer sesame oil, perilla oil, soy been oil to Western oil. They like sweat flavor the most and hot, salty taste in order. Thier favorite cooking method is a pot stew, soup and season. The difference between dietary habit and mental health based on an academic career, an allowance and a residential condition shows that the old who live alon have relatively terrible eating habit and the more learned, the better. The more pocket money they have, the better dietary habits they have. The old feel glommy in general and the old in an institution are more depressed and it is statistically significant.

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Immunogenicity and Safety of a Combined Hepatitis B and Haemophilus influenzae Type b Conjugate(PRP-OMP) Vaccine(ComvaxTM; Merck & Co.) in Korean Infants (한국 영아에서 B형 간염과 PRP-OMP의 혼합백신(ComvaxTM; MSD사)의 면역원성 및 안전성)

  • Chung, Eun Hee;Ma, Sang Hyuck;Hong, Young Jin;Kim, Kyung Hyo;Kim, Jong-Hyun;Lee, Jin A;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.13 no.2
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    • pp.163-173
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    • 2006
  • Purpose : To reduce the number of injections necessary to vaccinate young infants, various combined vaccines have been developed. The $Comvax^{TM}$ manufactured by Merck & Co. is a combination of Hepatitis B and PRP-OMP conjugate Haemophilus influenzae Type b vaccine. The purpose of this study is to evaluate the immunogenicity and safety of $Comvax^{TM}$ in Korean infants. Methods : The infants who were vaccinated at 0 months of age with Hepatitis B vaccine, were recruited for this study after parental informed consent was obtained. The subjects were vaccinated with $Comvax^{TM}$ at 2 and 4 months of age. At each visit, infants were also immunized with DTaP, inactivated poliovirus vaccine, and pneumococcal vaccine when indicated. The serum anti-PRP and anti-HBs were measured at 2 months after the 1st dose(4 months age), and the 2nd dose(6 months age) by the ELISA and chemiluminescent microparticle immunoassay method, respectively. The local and systemic adverse reactions of vaccination were monitored for 3 consecutive days after each immunization. Results : Among sixty-five healthy infants(35 male infants) enrolled in this study; fifty eight(32 male infants) completed the scheduled immunizations. The geometric mean titers (GMTs) of anti-PRP at 2 months after the 1st dose and the 2nd dose were 1.96 ${\mu}g/mL$ (95% CI; 1.38~2.78) and 10.02 ${\mu}g/mL$ (95% CI; 7.04~14.26), respectively. Anti-PRP ${\geq}1.0$ ${\mu}g/mL$, was obtained in 63.2%(95% CI; 53.75~72.65) after 1 dose, and 96.6%(95% CI; 93.05~100) after 2 doses. The GMTs of anti-HBs were 38.32 mIU/mL(95% CI; 22.42~65.51), and 101.17 mIU/mL(95% CI; 65.94~155.25) at 2 month after the 1st dose and 2nd dose of $Comvax^{TM}$, respectively. Anti-HBs ${\geq}10$ mIU/mL was observed in 73.7%(95% CI; 65.07~82.33) after 1 dose and 94.8%(95% CI; 90.45~99.15) after 2 doses. Most of the adverse reactions after vaccination were mild. Irritability, the most common systemic reaction, was observed in 24.8%, followed by drowsiness(19.2%), poor feeding(19.2%) and fever(7.2%). Among the local reactions tenderness was observed in 25.6%, redness(${\geq}5$ mm) in 19.2% and swelling(${\geq}5$ mm) in 4.8%. Conclusion : The $Comvax^{TM}$ vaccine was highly immunogenic for PRP and safe in Korean infants. Although the hepatitis B vaccine component was administered at 0, 2, 4 months, this study showed good immunogenicity against HBsAg.

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Radiotherapy Results for Recurrent Uterine Cervical Cancer after Surgery (수술 후 국소재발한 자궁경부암에서의 방사선치료 성적)

  • Ryu Mi Ryeong;Kay Chul Seung;Kang Ki Moon;Kim Yeon Shil;Chung Su Mi;Namkoong Sung Eun;Yoon Sei Chul
    • Radiation Oncology Journal
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    • v.17 no.3
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    • pp.217-222
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    • 1999
  • Purpose : To evaluate prognostic factors and survival rates of the patients who received radiation therapy for locally recurrent uterine cervical cancer after curative surgery. Materials and Methods : Between October 1983 and July 1990, fifty three patients who received radiation therapy for locally recurrent cervical cancer after curative surgery at the Department of Therapeutic Radiology, Kangnam St. Mary's Hospital, The Catholic University of Korea were analysed retrospectively. Age at diagnosis ranged from 33 to 69 years (median 53 years). Pathological analysis showed that forty five ($84.9\%$) patients had squamous cell carcinoma, seven ($13.2\%$) patients had adenocarcinoma, and one (1.9%) patient had adenosquamous cell carcinoma. The interval between hysterectomy and tumor recurrence ranged from 2 months to 25 years (mean 34.4 months). The recurrent sites were vaginal stump in 41 patients ($77.4\%$) and pelvic side wall in 12 patients ($22.6\%$). Recurrent tumor size was devided into two groups : less than 3 cm in 43 patients ($81.1\%$) and more than 3 cm in 10 patients ($18.9\%$). External beam irradiation of whole pelvis was done first up to 46.8 Gy to 50.4 Gy in 5 weeks to 6 weeks, followed by either external beam boost to the recurrent site in 18 patients ($34\%$) or intracavitary irradiation in 24 patients ($45.3\%$). Total dose of radiation ranged from 46.8 Gy to 111 Gy (median 70.2 Gy). Follow up period ranged from 2 to 153 months with a median of 35 months. Results : Overall response rate was $66\%$ (35/53). Among them, six patients ($17.1\%$) relapsed between 7 months and 116 months after radiation therapy (mean 47.7 months), Therefore overall recurrence rate was $45.3\%$. Overall five-year actuarial survival rate was $78.9\%$ and distant failure rate was $10\%$ (5/50). The significant prognostic factors affecting survival rate were interval between primary surgery and tumor recurrence (p=0.0055), recurrent tumor size (p=0.0039), and initial response to radiation therapy (p=0.0428). Complications were observed in 10 ($20/%$) patients, which included mild to moderate lower gastrointestinal, genitourinary, or skin manifestations. One patient died of pulmonary embolism just after intracavitary irradiation. Conclustion : Radiation therapy is the effective treatment for the patients with locally recurrent cervical cancer after curative surgery. These results suggest that interval between primary surgery and tumor recurrence, recurrent tumor size, and initial response to radiation therapy were significant prognostic factors for recurrent cervical cancer.

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Mitral Valve Repair for Mitral Regurgitation in Pediatric Patients (승모판폐쇄부전증를 가진 소아 환자에서 승모판성형술의 임상적 고찰)

  • Sim, Hyung-Tae;Yun, Tae-Jin;Park, Jeong-Jun;Jung, Sung-Ho;Uhm, Ju-Yeon;Jhang, Won-Kyoung;Kim, Young-Hwue;Ko, Jae-Kon;Park, In-Sook;Seo, Dong-Man
    • Journal of Chest Surgery
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    • v.40 no.8
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    • pp.536-545
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    • 2007
  • Background: Compared to adult patients, mitral regurgitation in pediatric patients is uncommon and it shows a wide spectrum of morphologic abnormalities. We retrospectively evaluated the midterm results of mitral valve repair in pediatric patients. Material and Method: Between December 1993 and August 2006, mitral valve repair was performed in 35 patients who were aged less than 18 years, The mean age was $5.3{\pm}5.3$ years and the mean body weight was $20,0{\pm}16.3\;kg$. 18 patients had associated cardiac anomalies. The most common pathologic finding was leaflet prolapse (n=17). The most common method of repair was the double orifice technique (n=15). Result: There was no early mortality. Eight patients underwent reoperation (24.2%), and five of them required mitral valve replacement. Among the four ring annuloplasty cases, two have developed mitral stenosis. Four out of the 14 double orifice cases required reoperation. One case of early mortality and one case of late mortality occurred in the reoperation cases. The 5-year survival rate and the freedom from reoperation rate were $93.3{\pm}4.6%$ and $76.1{\pm}8.2%$, respectively. The 5-year freedom from mitral valve replacement rate was $83.6{\pm}6.7%$. There was no significant risk factor for reoperation. Conclusion: The midterm results of mitral valve repair are very acceptable in pediatric patients compared to the adult cases, although the reoperation rate is slightly higher.

Mineralogy and Biogeochemistry of Intertidal Flat Sediment, Muan, Chonnam, Korea (전남 무안 갯벌 퇴적물에 관한 광물학적 및 생지화학적 연구)

  • Park, Byung-No;Lee, Je-Hyun;Oh, Jong-Min;Lee, Seuug-Hee;Han, Ji-Hee;Kim, Yu-Mi;Seo, Hyun-Hee;Roh, Yul
    • Journal of the Mineralogical Society of Korea
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    • v.20 no.1 s.51
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    • pp.47-60
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    • 2007
  • While sedimentological researches on Western coastal tidal flats of Korea have been much pelformed previously, mineralogical and biogeochemical studies are beginning to be studied. The objectives of this study were to investigate mineralogical characteritics of the inter-tidal flat sediments and to explore phase transformation of iron(oxyhydr)oxides and biomineralization by metal-reducing bacteria enriched from the inter-tidal flat sediments from Muan, Jeollanam-do, Korea. Inter-tidal flat sediment samples were collected in Chungkye-myun and Haeje-myun, Muan-gun, Jeollanam-do. Particle size analyses were performed using the pipette method and sedimentation method. The separates including sand, silt and clay fractions were examined by scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), and X-ray diffiaction (XRD). After enriching the metal-.educing bacteria from the into,-tidal flat sediments, the bacteria were used to study phase transformation of the synthesized iron (oxyhydr)oxides and iron biomineralization using lactate or glucose as the electron donors and Fe(III)-containing iron oxides as the electron accepters. Mineralogical studies showed that the sediments of tidal flats in Chung]rye-myun and Haeje-myun consist of quartz, plagioclase, microcline, biotite, kaolinite and illite. Biogeochemical researches showed that the metal-reducing bacteria enriched from the inter-tidal flat sediments reduced reddish brown akaganeite and mineralized nanometer-sized black magnetite. The bacteria also reduced the reddish brown ferrihydrite into black amorphous phases and reduced the yellowish goethite into greenish with formation of nm-sized phases. These results indicate that microbial Fe(III) reduction may play one of important roles in iron and carbon biogeochemistry as well as iron biomineralization in subsurface environments.