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Rapid Statistical Optimization of Cultural Conditions for Mass Production of Carboxymethylcellulase by a Newly Isolated Marine Bacterium, Bacillus velezensis A-68 from Rice Hulls (통계학적 방법을 사용한 해양미생물 Bacillus velezensis A-68균주의 섬유소 분해효소 생산 조건 최적화)

  • Kim, Bo-Kyung;Kim, Hye-Jin;Lee, Jin-Woo
    • Journal of Life Science
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    • v.23 no.6
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    • pp.757-769
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    • 2013
  • A microorganism producing carboxymethylcellulase (CMCase) was isolated from seawater, identified as Bacillus velezensis by analyses of 16S rDNA and partial sequences of the gyrA, and designated as B. velezensis A-68. The optimal conditions for production of CMCase by B. velezensis A-68 were established using response surface methodology (RSM). The optimal concentrations of rice hulls and yeast extract, and initial pH of the medium for cell growth were 60.2 g/l, 7.38 g/l, and 7.18, respectively, whereas those for production of CMCase were 50.0 g/l, 5.00 g/l, and 7.30. The analysis of variance (ANOVA) implied that the most significant factor for cell growth as well as production of CMCase was yeast extract. The optimal concentrations of $K_2HPO_4$, NaCl, $MgSO_4{\cdot}7H_2O$, and $(NH_4)_2SO_4$ in the medium for cell growth were 7.50, 1.00, 0.10, and 0.80 g/l, respectively, which were the same as those for production of CMCase. The optimal temperatures for cell growth and production of CMCase were 30 and $35^{\circ}C$, respectively. The maximal production of CMCase under optimized conditions was 83.8 U/ml, which was 3.3 times higher than that before optimization. In this study, rice hulls, agro-byproduct, were developed as a substrate for production of CMCase and time for production of CMCase was reduced to 3 days using a newly isolated marine bacterium.

Shear bond strength of dental CAD-CAM hybrid restorative materials repaired with composite resin (치과용 복합레진으로 수리된 CAD-CAM hybrid 수복물의 전단결합강도)

  • Moon, Yun-Hee;Lee, Jonghyuk;Lee, Myung-Gu
    • The Journal of Korean Academy of Prosthodontics
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    • v.54 no.3
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    • pp.193-202
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    • 2016
  • Purpose: This study was performed in order to assess the effect of the surface treatment methods and the use of bonding agent on the shear bond strength (SBS) between the aged CAD-CAM (computer aided design-computer aided manufacturing) hybrid materials and added composite resin. Materials and methods: LAVA Ultimate (LU) and VITA ENAMIC (VE) specimens were age treated by submerging in a $37^{\circ}C$ water bath filled with artificial saliva (Xerova solution) for 30 days. The surface was ground with #220 SiC paper then the specimens were divided into 9 groups according to the combination of the surface treatment (no treatment, grinding, air abrasion with aluminum oxide, HF acid) and bonding agents (no bonding, Adper Single Bond 2, Single Bond Universal). Each group had 10 specimens. Specimens were repaired (added) using composite resin (Filtek Z250), then all the specimens were stored for 7 days in room temperature distilled water. SBS was measured and the fractured surfaces were observed with a scanning electron microscope (SEM). One-way ANOVA and Scheffe test were used for statistical analysis (${\alpha}=.05$). Results: Mostly groups with bonding agent treatment showed higher SBS than groups without bonding agent. Among the groups without bonding agent the groups with aluminum oxide treatment showed higher SBS. However there was no significant difference between groups except two subgroups within LU group, which revealed a significant increase of SBS when Single Bond Universal was used on the ground LU specimen. Conclusion: The use of bonding agent when repairing an aged LAVA Ultimate restoration is recommended.

A Study of School Health Nursing Activity Performed Teachers Holding Additonal school Health (양호겸직교사의 학교보건간호 업무활동에 관한 조사연구)

  • Jung, Chan Gyoo;Chung, Yeon Kang
    • Journal of the Korean Society of School Health
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    • v.2 no.1
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    • pp.108-130
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    • 1989
  • The purpose of this study is to provide the basic data for the development of school health nursing activities by surveying realities of school health nursing activities in schools lacking in a school nurse performed by teachers holding additional school health. The subjects for the study was selected from teachers holding additional school health who participated in the annual training course for teachers holding additional school health in 1988 organized by Province Education Council. 105 teachers holding additonal school health from Kyung-gi Province, 85 from Chung-buk province, 50 from Chun-buk Province, answered the questionaire. The results can be epitomized as follows. 1. General characteristics of Teachers Holding Additional School Health. The majority of the subjects are female (94.3%) and 64.1% of the subjects are in their twenties, 79.5% of them graduated from four-year teacher's college, 54.5% of them are unmarried, 74.5% has less than one-year experience as a teacher holding additional school health. 2. General characteristics of schools 92.4% of schools are national, of public schools, and 91.9% are located in country, elementary schools are 64%, junior high schools are 35.4%. The annual school nursing budget is unknow to 89.2% of them. The school nursing organization is non- existent to 85.6%. 82.4% of the school nursing clinics occupy their place solely, or jointly. 3. Status of School Health Nursing Activities In the questionaire, School Health Nursing Activities arc divided into Health Program planning and Evaluation (4 items), Clinic Management (4 items), Health Education (4 items), Management of School Environment 98 items), Operating of School Health Organization (1 item) and Health Care Service (25 items). The answers to each item measured by the Likert-type scale reveals that in the activities of techcrs holding additional school health the practice rate in Management of School Environment is 55%, 47% in Health Education, 45% in Health Program Planning and Evaluation, 32% in Health Care Service, 27% in Operating of School Health Organization, and 27% in Clinic Management. 4. The Relation between Influencing variables and School Health Nursing Activities. The results are as follows. (1) Health Program Planning and Evaluation: religion, marital status ($P<0.05^{**}$) (2) Clinic Management: age, school health organization ($P<0.05^{**}$) (3) Health Education: age ($P<0.01^*$), religion ($P<0.05^{**}$), business except for school nursing ($P<0.05^{**}$), form of operation ($P<0.05^{**}$), the number of clinic client a month ($P<0.05^{**}$). (4) Management of School Health Environment: age, marital status, business except for school nursing ($P<0.05^{**}$), presence of the annual school health nursing budget ($P<0.01^*$), school health organization ($P<0.05^{**}$). (5) Operating of School Health Organization: There is a statistical significance in Education, Interest in School Nursing ($P<0.05^{**}$). 5. The Regional Relationship of School Health Nursing Activity. There is a statistically significal difference in Health Education ($P<0.05^{**}$) and Health Care Service ($P<0.01^*$) of elementary school located in Kyung-gi, Chung-buk, Chun-buk Province. There is a statistically significant difference Health Program Planning and Evaluation of junior high Schools located in Kyung-gi, Chung-buk, Province ($P<0.05^{**}$). 6. The Correlation in School Health Nursing Activities. The analysis of the correlation in the 6 fields of school Health Nursng Activities shows that there is a statistically significant difference between Clinic Management and health Education, Clinic Management and Operating of School Health Organization, and between management of School Environment and operating of School Health Organization ($P<0.05^{**}$). The conclusions are as follows The 40.5 percent of schools should arrange nurse teachers by regulation 38, relative to the application of the Law of Education. But, in reality, teachers who have nothing to do with nursing, hold school health as an additional job. And it is very difficult to expect the qualititive health management of school faculty and students. In the 85.6 percent of schools, there is no organization for school health. And also, persons in charge of pracitcal affairs perform the school health activity without any knowledge about annual school health nursing budget. In the school health nursing activity of teacheres holding additional school health, operating of school, health organization and clinic management are the most difficult to get the cooperation from the persons relate to school and communities. There are a lot of problems in performing the school health nursing activity without any disposition of school health teachers, therefore, it is necessary to supplement school health teachers who had a professional training in order to make efficient the school health nursing management for children who are about to attend a school.

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Optimization of Tube Voltage according to Patient's Body Type during Limb examination in Digital X-ray Equipment (디지털 엑스선 장비의 사지 검사 시 환자 체형에 따른 관전압 최적화)

  • Kim, Sang-Hyun
    • Journal of the Korean Society of Radiology
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    • v.11 no.5
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    • pp.379-385
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    • 2017
  • This study identifies the optimal tube voltages depending on the changes in the patient's body type for limb tests using a digital radiography (DR) system. For the upper-limp test, the dose area product (DAP) was fixed at $5.06dGy{\ast} cm^2$, and for the lower-limb test, the DAP was fixed at $5.04dGy{\ast} cm^2$. Afterwards, the tube voltage was changed to four different stages and the images were taken three times at each stage. The thickness of the limbs was increased by 10 mm to 30 mm to change in the patient's body type. For a quantitative evaluation, Image J was used to calculate the contrast to noise ratio (CNR) and signal to noise ratio (SNR) among the four groups, according to the tube voltage. For statistical testing, the statistically significant differences were analyzed through the Kruskal-Wallis test at a 95% confidence level. For the qualitative analysis of the images, the pre-determined items were evaluated based on a 5-point Likert scale. In both upper-limb and lower-limb tests, the more the tube voltage increased, the more the CNR and SNR of the images decreased. The test on the changes depending on the patient's body shape showed that the more the thickness increased, the more the CNR and SNR decreased. In the qualitative evaluation on the upper limbs, the more the tube voltage increased, the more score increased to 4.6 at the maximum of 55kV and 3.6 at 40kV, respectively. The mean score for the lower limbs was 4.4, regardless of the tube voltage. The more either the upper or lower limbs got thicker, the more the score generally decreased. The score of the upper limps sharply dropped at 40kV, whereas that of the lower limps sharply dropped at 50kV. For patients with a standard thickness, the optimized images can be obtained when taken at 45kV for the upper limbs, and at 50kV for the lower limbs. However, when the thickness of the patient's limbs increases, it is best to set the tube voltage at 50 kV for the upper limbs and at 55 kV for the lower limbs.

Study on the Chemical Management - 2. Comparison of Classification and Health Index of Chemicals Regulated by the Ministry of Environment and the Ministry of the Employment and Labor (화학물질 관리 연구-2. 환경부와 고용노동부의 관리 화학물질의 구분, 노출기준 및 독성 지표 등의 특성 비교)

  • Kim, Sunju;Yoon, Chungsik;Ham, Seunghon;Park, Jihoon;Kim, Songha;Kim, Yuna;Lee, Jieun;Lee, Sangah;Park, Donguk;Lee, Kwonseob;Ha, Kwonchul
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.25 no.1
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    • pp.58-71
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    • 2015
  • Objectives: The aims of this study were to investigate the classification system of chemical substances in the Occupational Safety and Health Act(OSHA) and Chemical Substances Control Act(CSCA) and to compare several health indices (i.e., Time Weighted Average (TWA), Lethal Dose ($LD_{50}$), and Lethal Concentration ($LC_{50}$) of chemical substances by categories in each law. Methods: The chemicals regulated by each law were classified by the specific categories provided in the respective law; seven categories for OSHA (chemicals with OELs, chemicals prohibited from manufacturing, etc., chemicals requiring approval, chemicals kept below permissible limits, chemicals requiring workplace monitoring, chemicals requiring special management, and chemicals requiring special heath diagnosis) and five categories from the CSCA(poisonous substances, permitted substances, restricted substances, prohibited substances, and substances requiring preparation for accidents). Information on physicochemical properties, health indices including CMR characteristics, $LD_{50}$ and $LD_{50}$ were searched from the homepages of the Korean Occupational and Safety Agency and the National Institute of Environmental Research, etc. Statistical analysis was conducted for comparison between TWA and health index for each category. Results: The number of chemicals based on CAS numbers was different from the numbers of series of chemicals listed in each law because of repeat listings due to different names (e.g., glycol monoethylether vs. 2-ethoxy ethanol) and grouping of different chemicals under the same serial number(i.e., five different benzidine-related chemicals were categorized under one serial number(06-4-13) as prohibited substances under the CSCA). A total of 722 chemicals and 995 chemicals were listed at the OSHA and its sub-regulations and CSCA and its sub-regulations, respectively. Among these, 36.8% based on OSHA chemicals and 26.7% based on CSCA chemicals were regulated simultaneously through both laws. The correlation coefficients between TWA and $LC_{50}$ and between TWA and $LD_{50}$, were 0.641 and 0.506, respectively. The geometric mean values of TWA calculated by each category in both laws have no tendency according to category. The patterns of cumulative graph for TWA, $LD_{50}$, $LC_{50}$ were similar to the chemicals regulated by OHSA and CCSA, but their median values were lower for CCSA regulated chemicals than OSHA regulated chemicals. The GM of carcinogenic chemicals under the OSHA was significantly lower than non-CMR chemicals($2.21mg/m^3$ vs $5.69mg/m^3$, p=0.006), while there was no significant difference in CSCA chemicals($0.85mg/m^3$ vs $1.04mg/m^3$, p=0.448). $LC_{50}$ showed no significant difference between carcinogens, mutagens, reproductive toxic chemicals and non-CMR chemicals in both laws' regulated chemicals, while there was a difference between carcinogens and non-CMR chemicals in $LD_{50}$ of the CSCA. Conclusions: This study found that there was no specific tendency or significant difference in health indicessuch TWA, $LD_{50}$ and $LC_{50}$ in subcategories of chemicals as classified by the Ministry of Labor and Employment and the Ministry of Environment. Considering the background and the purpose of each law, collaboration for harmonization in chemical categorizing and regulation is necessary.

Association between Sleep Duration, Dental Caries, and Periodontitis in Korean Adults: The Korea National Health and Nutrition Examination Survey, 2013~2014 (한국 성인에서 수면시간과 영구치 우식증 및 치주질환과의 관련성: 2013~2014 국민건강영양조사)

  • Lee, Da-Hyun;Lee, Young-Hoon
    • Journal of dental hygiene science
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    • v.17 no.1
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    • pp.38-45
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    • 2017
  • We evaluated the association between sleep duration, dental caries, and periodontitis by using representative nationwide data. We examined 8,356 subjects aged ${\geq}19$ years who participated in the sixth Korea National Health and Nutrition Examination Survey (2013~2014). Sleep duration were grouped into ${\leq}5$, 6, 7, 8, and ${\geq}9$ hours. Presence of dental caries was defined as caries in ${\geq}1$ permanent tooth on dental examination. Periodontal status was assessed by using the community periodontal index (CPI), and a CPI code of ${\geq}3$ was defined as periodontitis. A chi-square test and multiple logistic regression analysis were used to determine statistical significance. Model 1 was adjusted for age and sex, model 2 for household income, educational level, and marital status plus model 1, and model 3 for smoking status, alcohol consumption, blood pressure level, fasting blood glucose level, total cholesterol level, and body mass index plus model 2. The prevalence of dental caries according to sleep duration showed a U-shaped curve of 33.4%, 29.4%, 28.4%, 29.4%, and 31.8% with ${\leq}5$, 6, 7, 8, and ${\geq}9$ hours of sleep, respectively. In the fully adjusted model 3, the risk of developing dental caries was significantly higher with ${\leq}5$ than with 7 hours of sleep (odds ratio, 1.23; 95% confidence interval, 1.06~1.43). The prevalence of periodontitis according to sleep duration showed a U-shaped curve of 34.4%, 28.6%, 28.1%, 31.3%, and 32.5%, respectively. The risk of periodontitis was significantly higher with ${\geq}9$ than with 7 hours of sleep in models 1 and 2, whereas the significant association disappeared in model 3. In a nationally representative sample, sleep duration was significantly associated with dental caries formation and weakly associated with periodontitis. Adequate sleep is required to prevent oral diseases such as dental caries and periodontitis.

Association of Serum Vitamin D with Insulin Resistance and Beta Cell Function in Korean Health Checkup Examinees (건강검진 수검자에서 혈청 Vitamin D 수준과 인슐린저항성 및 β-세포 기능과의 관련성)

  • Kim, Han-soo;Ryu, So Yeon;Park, Jong;Han, Mi-Ah;Choi, Seong-Woo;Shin, Min-Ho
    • Journal of agricultural medicine and community health
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    • v.43 no.1
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    • pp.18-30
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    • 2018
  • Objectives: This study was conducted to examine the association of serum Vitamin D with insulin resistance and ${\beta}-cell$ function in Korean health checkup examinees. Methods: This study subjects were 374 healthy adults (199 males, 175 females) over the age of 20, who visited a general hospital medical center located in Haenam-gun, Jeollanam-do. To find the association of Vitamin D with HOMA-IR and $HOMA-{\beta}$, the used statistical analysis were ANOVA and ANCOVA. Results: Of the study subjects, the level of serum Vitamin D defined by deficient group, insufficient group and sufficient group was 38.5%, 48.1% and 13.4%, respectively. According to the level of serum Vitamin D, the mean values of HOMA-IR were $1.92{\pm}1.08$ in sufficient group, $1.99{\pm}1.04$ in the insufficient group and $2.91{\pm}1.05$ in deficient group and there were statistically significant different(p<0.001). The mean values of $HOMA-{\beta}$ were $84.69{\pm}1.07$ in sufficient group, $78.41{\pm}1.04$ in the insufficient group and $80.48{\pm}1.04$ in deficient group, and there were not significant. As a result of ANCOVA, adjusted mean of HOMA-IR were statistically significant different (p<0.001), but those of $HOMA-{\beta}$ were not statistically significant according to the level of serum Vitamin D. Conclusion: The insufficient level of serum Vitamin D was relatively high in healthy adults who live in rural area, and it was found that HOMA-IR significantly increased when Vitamin D was deficient. To prevent insulin resistance or diabetes, it is necessary to provide sufficient information related to sufficient production of Vitamin D such as Vitamin D supplement, sun exposure, food intake and etc.

An Analysis of BMD Changes With Preoperative and Postoperative Premenopausal Breast Cancer Patient (폐경 전 유방암 환자의 치료 전.후 골밀도 변화 분석)

  • Kim, Su-Jin;Son, Soon-Yong;Choi, Kwan-Woo;Lee, Joo-Ah;Min, Jung-Whan;Kim, Hyun-Soo;Ma, Sang-Chull;Lee, Jong-Seok;Yoo, Beong-Gyu
    • Journal of radiological science and technology
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    • v.37 no.4
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    • pp.279-286
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    • 2014
  • The purpose of this study is to provide basic data of comparing BMD(bone mineral density) value of preoperative breast cancer patient and postoperative breast cancer patient due to bone loss with radiation/chemical therapy. The participants consisted of 254 breast cancer patients with BMD after having surgery and treatment from March 2007 to September 2013. Except for 84 patients with menopause or hysterectomy and we have analysed 171 patients. The BMD value(lumbar spine and femur) of before and after treatment from PACS by dure-energy X-ray absorptiometry was analyzed. First, we found variation of entire BMD and BMD according to treatment type, and analyzed detailed correlation by using marital status, number of children, presence of feeding, age of menarche, breast cancer therapy types as variable. Data was analyzed by using SPSS for Windows Program(version 18.0). BMD was decreased 7.1% in lumbar spine, 3.1% in femur respectively(p<.01). Also there is relatively high decrement($0.067g/cm^2$) in group who had just chemotherapy in femur(p<.05). There is decrement depend on marital status, number of children, presence of feeding, age of menarche, breast cancer therapy types but there was no statistical significance. The results show that BMD was decreased after treatment in premenopausal breast cancer patient, patient who had relatively high decrement need to be included high-risk group. As a result, aggressive prevention policy would be necessary.

The Effect of Angiotensin Converting Enzyme Gene Polymorphism in Children with Henoch-Schonlein Purpura Nephritis (Henoch-Schonlein Purpura 신염에서 안지오텐신 전환효소 유전자 다형성의 영향)

  • Ha, Chang Woo;Kim, Ji Young;Lee, Jeong Nyeo;Lee, Jeong Hwa;Chung, Woo Yeong
    • Clinical and Experimental Pediatrics
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    • v.45 no.7
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    • pp.884-890
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    • 2002
  • Purpose : Henoch-Schonlein purpura(HSP) nephritis has been reported to vary from 25 to 50% among HSP patients and is a common cause of chronic glomerulonephritis in children. In our study, we evaluated the distribution and the association of the Insertion/Deletion(I/D) polymorphism of angiotensin converting enzyme(ACE) gene with clinical manifestations, particularly proteinuria in children with HSP nephritis, compared with that in HSP. Methods : ACE gene polymorphism was determined in children with HSP nephritis(n=33) and HSP(n=28) who were diagnosed in Busan Paik hospital from January 1996 to June 2001. The I/D polymorphism of ACE gene was determined by PCR amplication of genomic DNA. Results : The ACE I/D genotype frequency was DD : 25%, ID : 50%, II : 25% in HSP and DD : 24 %, ID : 46%, II : 30% in HSP nephritis, there was no significant difference in the genotype and allele frequencies between two groups. When statistical analysis was done according to the presence of D allele, the amount of 24-hour urinary protein excretion and the incidence of moderate to heavy proteinuria(>$500mg/m^2/day$) at onset and last follow-up were higher in DD/ID genotype than in those in II genotype, but these differences were not statistically significant. Conclusion : We suggest a lack of association between I/D polymorphism of ACE gene and clinical manifestations in children with HSP nephritis. However, further follow-up studies based on a sufficient number of patients and long term follow up periods are necessary to confirm the role of I/D polymorphism of ACE gene in children with HSP nephritis.

Renal Anomalies in Children with Turner Syndrome (Turner 증후군 환자에서 신기형에 관한 연구)

  • Kim, Ji Young;Hong, Sun Young;Park, Young Mi;Park, Yong Hoon;Chung, Woo Yeong
    • Clinical and Experimental Pediatrics
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    • v.45 no.7
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    • pp.891-895
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    • 2002
  • Purpose : The prevalence of renal anomalies in Turner syndrome(TS) has been reported to vary from 33% to 60%. The purpose of this study was to clarify the true incidence of renal malformations in Korean TS. Methods : We evaluated 33 patients with Turner syndrome diagnosed by karyotype in Inje University Busan Paik hospital and Youngnam University from January 1995. Intravenous pyelography(IVP) was performed on all patients; abdominal ultrasonography and 99mTc-DMSA renal scan were performed on some. Cytogenetic analysis was performed on all patients with peripheral blood lymphocytes. Results : Of the total 33 patients, the karyotype showed 45, X in 18(54.5%) patients, mosaicism in 11(33.3%) patients and structural aberration in 4(12.2%) patients. The overall incidence of renal anomalies was 36.4%. The renal anomalies included four cases of horeshoe kidney, six cases of abnormal renal collecting system one case of single kidney and one case of malrotation. The incidence of renal anomalies in 45, X karotype(44.4%) showed a higher rate than that of mosaicism and structural aberration(26.7%), but there is no statistical significance. Conclusion : The incidence of renal anomalies in Korean TS reveals 36.4%. This rate is similar to other foreign TS studies. We recommend that renal ultrasonography or IVP for investigation of renal anomalies should be done as a screening procedure for the better quality of life in patients with TS.