• Title/Summary/Keyword: 95% 신뢰구간

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Dose verification for Gated Volumetric Modulated Arc Therapy according to Respiratory period (호흡연동 용적변조 회전방사선치료에서 호흡주기에 따른 선량전달 정확성 검증)

  • Jeon, Soo Dong;Bae, Sun Myung;Yoon, In Ha;Kang, Tae Young;Baek, Geum Mun
    • The Journal of Korean Society for Radiation Therapy
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    • v.26 no.1
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    • pp.137-147
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    • 2014
  • Purpose : The purpose of this study is to verify the accuracy of dose delivery according to the patient's breathing cycle in Gated Volumetric Modulated Arc Therapy Materials and Methods : TrueBeam STxTM(Varian Medical System, Palo Alto, CA) was used in this experiment. The Computed tomography(CT) images that were acquired with RANDO Phantom(Alderson Research Laboratories Inc. Stamford. CT, USA), using Computerized treatment planning system(Eclipse 10.0, Varian, USA), were used to create VMAT plans using 10MV FFF with 1500 cGy/fx (case 1, 2, 3) and 220 cGy/fx(case 4, 5, 6) of doserate of 1200 MU/min. The regular respiratory period of 1.5, 2.5, 3.5 and 4.5 sec and the patients respiratory period of 2.2 and 3.5 sec were reproduced with the $QUASAR^{TM}$ Respiratory Motion Phantom(Modus Medical Devices Inc), and it was set up to deliver radiation at the phase mode between the ranges of 30 to 70%. The results were measured at respective respiratory conditions by a 2-Dimensional ion chamber array detector(I'mRT Matrixx, IBA Dosimetry, Germany) and a MultiCube Phantom(IBA Dosimetry, Germany), and the Gamma pass rate(3 mm, 3%) were compared by the IMRT analysis program(OmniPro I'mRT system software Version 1.7b, IBA Dosimetry, Germany) Results : The gamma pass rates of Case 1, 2, 3, 4, 5 and 6 were the results of 100.0, 97.6, 98.1, 96.3, 93.0, 94.8% at a regular respiratory period of 1.5 sec and 98.8, 99.5, 97.5, 99.5, 98.3, 99.6% at 2.5 sec, 99.6, 96.6, 97.5, 99.2, 97.8, 99.1% at 3.5 sec and 99.4, 96.3, 97.2, 99.0, 98.0, 99.3% at 4.5 sec, respectively. When a patient's respiration was reproduced, 97.7, 95.4, 96.2, 98.9, 96.2, 98.4% at average respiratory period of 2.2 sec, and 97.3, 97.5, 96.8, 100.0, 99.3, 99.8% at 3.5 sec, respectively. Conclusion : The experiment showed clinically reliable results of a Gamma pass rate of 95% or more when 2.5 sec or more of a regular breathing period and the patient's breathing were reproduced. While it showed the results of 93.0% and 94.8% at a regular breathing period of 1.5 sec of Case 5 and 6, it could be confirmed that the accurate dose delivery could be possible on the most respiratory conditions because based on the results of 100 patients's respiratory period analysis as no one sustained a respiration of 1.5 sec. But, pretreatment dose verification should be precede because we can't exclude the possibility of error occurrence due to extremely short respiratory period, also a training at the simulation and careful monitoring are necessary for a patient to maintain stable breathing. Consequently, more reliable and accurate treatments can be administered.

Roasting Conditions for Optimization of Citri Unshii Pericarpium Antioxidant Activity Using Response Surface Methodology (반응표면분석을 이용한 진피의 항산화 활성 최적화를 위한 로스팅 조건 확립)

  • Hwang, Hyun Jung;Park, Jeong Ah;Choi, Jeong In;Kim, Hee Soo;Cho, Mi Sook
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.2
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    • pp.261-268
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    • 2016
  • This study was conducted to establish roasting conditions for optimization of Citri Unshii Pericarpium antioxidant activity using response surface methodology (RSM). A central composite design was applied to investigate the effects of two independent variables, namely roasting temperature ($40{\sim}100^{\circ}C$; $X_1$) and roasting time ($5{\sim}15min$; $X_2$), on responses such as electron donating ability ($Y_1$), total phenolic content ($Y_2$), total flavonoid content ($Y_3$), and hydroxyl radical scavenging activity ($Y_4$). The maximum electron donating ability was 72.38% at a roasting temperature of $71.12^{\circ}C$ and roasting time of 9.39 min. The maximum total phenolic content was 10.76 mg tannic acid equivalents/g at a roasting temperature of $69.71^{\circ}C$ and roasting time of 8.39 min. The maximum total flavonoid content was 105.99 mg quercetin equivalents/100 g at $72.54^{\circ}C$ and 8.64 min. The maximum hydroxyl radical scavenging activity was 60.33% at $68.97^{\circ}C$ and 9.84 min. Based on the superimposition of three dimensional RSM with respect to electron donating ability, total phenolic content, total flavonoid content, and hydroxyl radical scavenging activity under various conditions, optimum conditions were established as follows: roasting temperature of $70.90^{\circ}C$ and roasting time of 9.03 min.

The Seroprevalence and Related Factors of Helicobacter pylori Infection (Helicobacter pylori 감염의 유병률과 관련요인에 관한 연구)

  • Kim, Yeung-Wook;Lee, Su-Ill;Cho, Byung-Mann;Koh, Kwang-Wook;Kim, Young-Sil;Kang, Su-Yong;Cha, Oae-Ri;Kim, Don-Kyoun
    • Journal of Preventive Medicine and Public Health
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    • v.29 no.3 s.54
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    • pp.669-678
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    • 1996
  • Helicobacter pylori is now recognized as causative agent of chronic gastritis and peptic ulcer, and strongly associated with development of gastric carcinoma. With development of sensitive and specific serologic tests to identify individuals infected with Helicobacter pylori, the epidemiologic study of this diseases has been investigated. But it's transmission route is not established, yet. The purpose of this study is to measure the prevalence of Helicobacter pylori infection in healthy children and young adults and to evaluate related factors for Helicobacter pylori infection in Korea. The seroprevalence of Ig G antibodies to Helicobacter pylori was determined using a Enzyme Linked Immunosorbent Assay and we obtained the information, such as demographic characteristics, monthly household income, numbers of family members in the house, numbers of persons using same room, type of house, and type of drinking water through the questionnaire survey. The observed overall seropositivity rate was 25.7%. The rate is increased progressively from 5.8% in the age group $1\sim3$ years to 44.4% in the age group $20\sim29$years($\chi^2$ for trend, p<0.001). Especially, the rate increased steeply from 6.5% in the age group $4\sim6$ years to 20.8% in the age group $7\sim9$ years, and this suggested that elementary school age was the major acquisition time of Helicobacter pylori infection. In multivariate logistic regression model, age, numbers of family members in the house, and type of house was statistically significant variables for Helicobacter pylori infection. Each odds ratio(93% CI) were as follows; base to age group $1\sim9$ years, age group $10\sim19$ years $3.6(2.0\sim6.4)$, age group $20\sim29$ years $7.3(4.1\sim13.1)$ and base to group of $1\sim3$ family members, group of $4\sim5$ family members $2.1(1.1\sim4.0)$, group of 6 or more family members $2.7(1.3\sim5.4)$ and base to apartment, single and multihouse $1.9(1.1\sim3.5)$. Sex, monthly household income, numbers of persons using same room, and type of drinking water was not statistically significant for Helicobacter pylori infection.

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Comparision of Signal-Averaged Electrocardiography (SAECG) Determined by Flank Lead System (FLS) and Pyramidal Lead System (PLS) in Healthy Young Adults (정상 성인의 직교유도체제와 피라미드유도체제에 의한 신호 가산 평균심전도의 비교)

  • Jang, Byeong-Ik;Kang, Seung-Ho;Kim, Hyeung-Il;Shin, Dong-Gu;Kim, Young-Jo;Shim, Bong-Sup;Lee, Hyun-Woo
    • Journal of Yeungnam Medical Science
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    • v.10 no.1
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    • pp.179-189
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    • 1993
  • It has recently become possible to record electrical activity originating from abnormally conducting myocardium from the body surface with high - gain amplification and averaging technique. These signals, which result from delayed ventricular activation(late potentials), have been recorded in patients with documented ventricular tachyarrythmia. Several electrode lead system for detecting ventricular late potential were introduced. Pyramidal electrode lead system(PLS) is useful. Also interpretation of SAECG in the young could be of value in detecting those at risk for episodic ventricular tachycardia, but suffer from a lack of data in normal young people. Selection of subjects : For this study, normal healthy young adult volunteers (age: mean 24 years) were recruited from the medical students at Yeungnam University Hospital, Internal Medicine. Twenty fourths male and seventeenths female subjects were selected. All subjects had normal resting ECGs as judged from both the standard 12 channel lead and echocardiography, and none had a history of cardiovascular disease. All subjects were considered to be in good general physical condition. Signal-averaged electrocardiography : In order to obtain low noise recordings with a small number of averaging cycles, all subject ware asked to relax completely in the supine position. Silver/silver chloride electrodes were attached after the skin was cleaned with alcohol, to constitute classic flank lead system(FLS) and pyramidal lead system(PLS). Signals were recorded and processed using a commercially available microprocessor-augmented ECG cart(Marquette Electronics, USA) suitable for portable bedside recording. There was no difference between normal values, determined by FLS and PLS at high pass filtering of 25 Hz and 80 Hz, but significant, difference was found in HFLAD and RMS-40 of 40 Hz(p<0.05). These results will provide a basis for interpretations of SAECG, determined by FLS and PLS in healthy young adults with normal QRS duration.

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Alcohol Intake in Relation to Cardiovascular Risk Factors among (Middle Age) South Korean Men (한국의 중년기 남성의 심혈관계 질환 위험요인과 음주섭취와의 관련성)

  • Park, Kyung-Min
    • Research in Community and Public Health Nursing
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    • v.9 no.1
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    • pp.232-241
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    • 1998
  • 음주습관과 심혈관계 질환 위험요인사이의 관련성을 파악하기 위하여, 1996년 한국 경북에 있는 도시지역 한 철강회사에서 40-50대(40-59세) 남자 근로자 3444명으로부터 공복시 혈액을 10m1 채취하여 혈청지질, 혈당, Uric acid를 측정하고 신장, 체중, 혈압(10-20분 휴식후 측정)과 EKG를 측정하였다. 과거병력, 현재 건강상태, 음주량과 기간 및 음주종류를 포함한 생활습관, 흡연량/일, 운동시간/주 등의 설문지를 작성하였다. 알콜 소비량은 양-빈도의 Index에 의해 측정되었다. 한국 중년 남자에 대한 음주량, 음주기간, 알콜종류등에 따른 심혈관계 질환의 위험요인 유무 정도를 알아보기 위해, 비음주자를 기준으로하여 비교대상군은 금주자와 음주량(2군) 등에 의해 3군으로 분류하였으며, 음주기간에 따른 심혈관계 질환의 위험요인 유무정도를 알아보기 위해 비음주자을 기준으로하여 비교 대상군은 금주자와 음주기간(4군)에 따라 5군으로 분류하였다. 알콜종류에 따른 심혈관계 질환의 위험요인 유무정도를 알아보기 위해 비음주자을 기준으로하여 비교 대상군은 금주자와 음주알콜종류(3군)에 따라 4군으로 분류하였다. 심혈관계 질환 위험요인은 기준되는 범주를 2개(Table 1)로 분류하여 2*2표를 이용하여 odds ratio(dummy variable로 처리), ${\beta}$-coefficient와 표준오차를 이용해서 신뢰구간(95% C.I.)을 구하여 유의성 검정을 하였다. 금주자의 정의는 과거 3달 이상 술을 마시지 않는 사람을 말한다. 연구 집단의 평균 연령은 $44.4{\pm}3.9$세 이며, 비음주자는 649명으로 18.9%, 금주자는 70명(2.0%)이며 음주자는 2725명(79.1%)이다. 음주자중 에타놀 섭취를 평균 100.5g/주(median) 미만인 군은 1239명으로 연구집단 3444명중 35.7%이며, 평균 100.5g/주(median) 이상 음주군은 1276명으로 44.5%이었다. 3444명중 1532명(44.5%) 이 맥주와 소주를 섞어서 마시는 사람이었다. 음주 양에서, 연령, 흡연 양, 흡연 기간, 운동, 음주기간, 알콜종류 등을 통제하여 logistic regression한 결과, 비음주자에 비해 중정도 음주자(${\ge}$100.5gm/week ethanol)의 확장기 혈압의 Odds ratio는 1.33배로 유의하게 높았다(P<0.05). 다른 요인들은 통계적으로 유의한 차이를 보이지 않았다. 알콜종류에서도 연령, 흡연 양, 흡연 기간, 운동, 음주양, 음주기간, 등을 통제한, 비음주자에 비해 맥주와 소주를 섞어 마시는 음주자의 확장기 혈압의 Odds ratio는 1.38배로 유의하게 높았다(P<0.01). 다른 요인들은 통계적으로 유의한 차이를 보이지 않았다. 반면에 음주 습관 중 음주기간에서는 연령, 흡연양, 흡연 기간, 운동, 음주양, 알콜종류 등을 통제한 logistic regression 분석 결과 유의한 차이를 보인 것은 없었다. 그러나 음주기간과 심혈관계 질환 위험요인중 수축기와 확장기 혈압과의 관계는 J 모양을 나타내었다 . 수축기 혈압의 금주자군은 비차비가 1.0보다 약간 낮고(Odds ratio=0.88) 음주기간이 2-10년인 군의 Odds ratio=1.14, 음주기간이 11-20 년인군의 Odds ratio =1.18, 21년 이상인 군의 Odds ratio=1.20로 비음주자의 odds ratio=1에 비해 점차적으로 위험이 높아졌다. 확장기 혈압의 금주자군은 비차비가 1.0보다 약간 낮고(Odds ratio=0.91), 음주기간이 1년 이하인 군의 Odds ratio=1.18, 음주기간이 2-10 년인 군의 Odds ratio=1.23, 음주기간이 11-20 년인 군의 Odds ratio=1.27, 21년 이상인 군의 Odds ratio=1.27로 비음주자의 odds ratio=1에 비해 점차적으로 위험이 높아졌다.

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Genetic Polymorphism of Epoxide Hydrolase and GSTM1 in Chronic Obstructive Pulmonary Disease (만성폐쇄성폐질환 발생에 Epoxide hydrolase와 GSTM1유전자 다형성의 의의)

  • Park, Sang Sun;Kim, Eun Joung;Son, Chang Young;Wi, Jeong Ook;Park, Kyung Hwa;Cho, Gye Jung;Ju, Jin Young;Kim, Kyu Sik;Kim, Yu II;Lim, Sung Chul;Kim, Young Chul;Park, Kyung Ok;Na, Kook Joo
    • Tuberculosis and Respiratory Diseases
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    • v.55 no.1
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    • pp.88-97
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    • 2003
  • Background : Although smoking is a major cause of chronic obstructive pulmonary disease (COPD), only 10-20% of cigarette smokers develop symptomatic COPD, which suggests the presence of genetic susceptibility. This genetic susceptibility to COPD might depend on variations in the activities of the enzyme that detoxify hazardous chemical products, such as microsomal epoxide hydrolase (mEPHX) and glutathione-S transferase M1 subunit (GSTM1) genes. Methods : The genotypes of 58 patients with COPD, and 79 age matched control subjects, were determined by a polymerase chain reaction, followed by restriction fragment length polymorphism (PCR-RFLP) for the mEPHX, and multiplex PCR for the GSTM1. Results : GSTM1 was deleted in 53.3% of the subjects. There was no difference in GSTM1 deletion rates between the COPD patients (32/58, 55.2%) and the control subjects (41/79, 51.9%). The combination patterns of two polymorphisms of mEPHX showed slow enzyme activity in 29(21.2%), normal in 73(53.3%) and fast in 32(23.4%). The COPD group (7/57, 12.3%) showed a significantly lower incidence of slow enzyme activity compared to the control subjects (22/77, 28.6%, p<0.05). However, when the COPD and control groups were compared with smokers only, there were no significant differences in the genotypes of GSTM1 and mEPHX. Conclusion : The genotypes of GSTM1 and mEPHX were not significant risk factors of COPD in this cohort of study.

The Proportion of Rifabutin-susceptible Strains among Rifampicin-resistant Isolates and Its Specific rpoB Mutations (한국에서 분리된 리팜핀 내성 균주에서의 리파부틴 감수성 정도 및 관련 rpoB 유전자 돌연변이의 특성에 관한 연구)

  • Lew, Woo Jin;Park, Young Kil;Kim, Hee Jin;Chang, Chulhun;Bai, Gill Han;Kim, Sung Kyu
    • Tuberculosis and Respiratory Diseases
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    • v.59 no.3
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    • pp.257-265
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    • 2005
  • Background : Rifabutin (ansamycin) is a spiro-piperidyl rifamycin, which is highly active against Mycobacterium tuberculosis. It has been found that some clinical isolates of tubercle bacilli that are resistant to rifampicin are susceptible to rifabutin, with some patients with multi-drug resistant pulmonary tuberculosis having shown favorable clinical and bacteriological responses to the rifabutin. This study was conducted to find the proportion of rifabutin-susceptible strains among rifampicin-resistant isolates from Korean MDR-TB patients, and investigate the presence of specific rpoB mutations, which may confer resistance to rifampicin, but not to rifabutin. Methods : 201 rifampicin-resistant and 50 pan-susceptible M. tuberculosis isolates were randomly selected for this study. The isolates were retested at rifampicin and rifabutin concentrations of 0, 20, 40 and $80{\mu}g/ml$, respectively. The isolates that grew at and/or over a rifabutin concentration of $20{\mu}g/ml$ were judged rifabutin-resistant. The rpoB gene was extracted from the isolates, and then amplified for direct sequencing to investigate specific rpoB mutations that conferred rifabutin- susceptibility but rifampicin-resistance. Results : Out of the 201 rifampicin-resistant M. tuberculosis, 41 strains (20.4%) were susceptible to rifabutin using the absolute concentration method on Lowenstein-Jensen media. The rpoB mutation types that showed susceptibility to rifabutin were Leu511Pro, Ser512Arg, Gln513Glu, Asp516Ala, Asp516Gly, Asp516Val, Asp516Tyr, Ser522Leu, His526Asn, His526Leu, His526Cys, Arg529Pro and Leu533Pro. A reverse hybridization technique was able to detect 92.5% of the rifabutin-susceptible isolates, with a specificity of 96.1% among 195 M. tuberculosis isolates with the rpoB mutation. Conclusions : Around 20% of the rifampicin-resistant isolates in Korea showed susceptibility to rifabutin, which was associated with some specific mutations of rpoB. Rifabutin could be used for the treatment of MDR-TB patients, especially when drug susceptibility testing reveals susceptibility to rifabutin.

Clinical Value of a Desktop Spirometer (HI-801) for Spirometry Screening (선별 검사를 위한 탁상용 폐활량기 (HI-801)의 임상적 유용성에 관한 고찰)

  • Choi, Hye Sook;Choi, Cheon Woong;Park, Myung Jae;Kang, Hong Mo;Yoo, Hong Ji
    • Tuberculosis and Respiratory Diseases
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    • v.62 no.4
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    • pp.276-283
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    • 2007
  • Background: A national health care initiative recommends routine spirometry screening of all smokers over age 45 or patients with respiratory symptoms. In response to the recommendation, new, simple, and inexpensive desktop spirometers for the purpose of promoting widespread spirometric screening were marketed. The performance of these spirometers was evaluated in vivo testing with healthy subjects. However, the clinical setting allows spirometric assessment of various pathologic combinations of flow and volume. Objective: The aim of this study was to compare the accuracy of a desktop spirometer to a standard laboratory spirometer, in a clinical setting with pathologic pulmonary function. Method: In a health check-up center, where screening pulmonary funct test was performed using the HI-801 spirometer. Subjects who revealed the ventilation defect in screening spirometry, performed the spirometry again using the standard Vmax spectra 22d spirometer in a tertiary care hospital pulmonary function laboratory. Pulmonary function test with both spirometer was performed according to the guidelines of the American Thoracic Society. Results: 109 patients were enrolled. Pulmonary function measurements (FVC, $FEV_1$, PEFR, FEF25%-75%) from the HI-801 correlated closely (r=0.94, 0.93, 0.81, 0.84, respectively) with those performed with the Vmax spectra 22d and showed the good limits of agreement and differences between the 2 devices; FVC +0.35 L, $FEV_1$ +0.16 L, PEFR +1.85 L/s, FEF25%-75%-0.13 L/s. With the exception of $FEV_1$, FEF25%-75%, these differences were significant(p<0.05) but small. Conclusion: The HI-801 spirometer is comparable to the standard laboratory spirometer, Vmax spectra 22d, with high accurary for $FEV_1$ and FVC and acceptable differences for clinical use.

The diagnostic significance of serum bile acid on total parenteral nutrition induced cholestasis in premature infants (총정맥영양에 의한 미숙아 담즙정체증에서 혈청 담즙산의 진단적 의의)

  • Park, Kyoung Soo;Shin, Myung Seok;Chang, Mea Young
    • Clinical and Experimental Pediatrics
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    • v.49 no.8
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    • pp.851-856
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    • 2006
  • Purpose : The purpose of this study is to find out the diagnostic significance of serum bile acid on total parenteral nutrition induced cholestasis in premature infants. Methods : Infants without cholestasis were classified into postnatal days and each change of serum bile acid was measured and analyzed. Also, the serum direct bilirubin, serum bile acid, ${\gamma}$-glutamic acid transferase, and alkaline phosphatase of premature infants with total parenteral nutrition induced cholestasis were measured for comparison and analysis of their correlation. Results : Changes of serum bile acid analysis after birth showed no significant difference between boys and girls, between premature infants and term infants without cholestasis. Serum bile acid levels are constant after two weeks after birth in neonates without cholestasis. In premature infants with total parenteral nutrition induced cholestasis, the increase of serum direct bilirubin over 2 mg/dL was $34.9{\pm}18.3$ days after birth, and the increase of serum bile acid was $28.1{\pm}18.3$ days. Its increase was about 1 week faster than serum direct bilirubin, however, there was no statistical significance(P=0.114). Comparing analysis of serum bile acid, ${\gamma}$-glutamic acid transferase, and alkaline phosphatase, serum bile acid showed the highest correlation to serum direct bilirubin(r=0.487, P=0.000). Conclusion : Serum bile acid is an important parameter of total parenteral nutrition induced cholestasis in premature infants and will be useful for early diagnosis and treatment.

Analysis of Prenatal and Postnatal Factors Associated with Complications and Prognosis in Premature Infants with Leukemoid Reaction (백혈병양반응을 보인 미숙아의 합병증과 예후에 관한 산전과 산후 인자에 대한 분석)

  • Kwon, Se-Ho;Lee, Byoung-Kook;Lee, Heun-Ji;Na, So-Young;Lee, Jung-Ha;Park, Su-Yeon;Kang, Eun-Kyeung;Kim, Do-Hyeon;Lee, Kwan;Kim, Hee-Sup
    • Neonatal Medicine
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    • v.15 no.2
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    • pp.151-159
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    • 2008
  • Purpose : This study determined the prenatal and postnatal factors associated with complications and prognosis in premature infants with leukemoid reaction. Methods : We retrospectively reviewed the medical records of premature infants with gestational ages <37 weeks and low birth weights (<2,500 g) who were admitted immediately after birth to the neonatal intensive care unit at the Dongguk University Ilsan Hospital between June 2005 and July 2006. A leukemoid reaction was defined as an absolute neutrophil count (ANC) >30,000/$mm^3$. The infants who had leukemoid reaction comprised the study group, while the remainder of infants made up the control group. The relationships between maternal and neonatal variables and ANC were studied. Results : Leukemoid reaction was detected in 3.1% of the study infants (8 of 252). Factors more frequently associated with infants with leukemoid reaction were as follows: maternal chorioamnionitis, high levels of maternal and infant C-reactive protein, gestational age <37 weeks, birth weight <2,500 g, low Apgar score, prolonged ventilator support, and a high incidence of bronchopulmonary dysplasia (BPD). However, there were no significant differences with respect to the antenatal usage of steroids, the incidences of patent ductus arteriosus, necrotizing enterocolitis, intraventricular hemorrhage, retinopathy of prematurity, and mortality between the two groups. Conclusion : Leukemoid reaction in premature infants was associated with chorioamnionitis and high levels of serum C-reactive protein in mothers and infants, and BPD in infants. These findings suggest that leukemoid reaction is secondary to inflammation caused by infection.