• Title/Summary/Keyword: pooled correlation

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Comparison of Gadobenate Dimeglumine and Gadopentetate Dimeglumine for Breast MRI Screening: a Meta-analysis

  • Yang, Xiao-Ping;Han, Yue-Dong;Ye, Jian-Jun;Chen, Gang;Luo, Ying;Ma, Hong-Xia;Yu, Xue-Wen;Niu, Juan-Qin;Ren, Fang-Yuan;Guo, You-Ming
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.12
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    • pp.5089-5095
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    • 2014
  • Background: As a common and essential contrast medium at present, gadobenate dimeglumine has shown better performance than some other agents when applied to Breast Magnetic Resonance Imaging Screening (Breast MRI Screening). Nevertheless, reports on the diagnostic performance of these two mediums (gadobenate dimeglumine and gadopentetate dimeglumine) are not completely consistent. Objective: To assess the diagnostic value of gadobenate dimeglumine and gadopentetate dimeglumine for Breast MRI Screening in patients suffering from breast cancer and to provide more convinced evidence to guide clinical practice in terms of appropriate contrast agents. Data Sources and Review Methods: Original articles in English and Chinese published before January 2013 were selected from available databases (The Cochrane Library, PUBMED, EMBASE, Chinese Biomedical Literature Database, Chinese Scientific Journals Full-text Database, Chinese Journal Full-text). The criteria for inclusion and exclusion were based on the standard for diagnosis tests. Meta-Disc software (Version 1.4) was used for data analysis. Then, the area under curve (AUC) of SROC and the spearman rank correlation of sensitivity against (1-specificity) were calculated. Results: Total of 17 researches involving 1934 patients were included. The pooled sensitivity of gadobenate dimeglumine and gadopentetate dimeglumine were 0.99 (0.97, 1.00) and 0.93 (0.88, 1.00) respectively. The pooled specificity for these two contrast agents were 0.924 (0.902, 0.943) and 0.838 (0.817, 0.858) respectively, and the AUC of SROC curve were 0.9781 and 0.9215 respectively. Conclusions: Gadobenate dimeglumine can be regarded as a more effective and feasible contrast medium for Breast MRI Screening. At least 5% differences in diagnostic performance are usually considered as clinically relevant.

Prognostic Value of C-Reactive Protein in Esophageal Cancer: a Meta-analysis

  • Zheng, Tian-Liang;Cao, Ke;Liang, Cui;Zhang, Kai;Guo, Hai-Zhou;Li, De-Ping;Zhao, Song
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.19
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    • pp.8075-8081
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    • 2014
  • Background: The classical inflammatory biomarker, C-reactive protein (CRP), has been identified to be related to progression of esophageal cancer. Some research showed that elevated pretreatment serum CRP indicated a poor prognosis, but results have been inconsistent. Materials and Methods: We searched the Medline, Embase and the Cochrane Central Search Library for suitable studies and a meta-analysis of eleven (1,886 patients) was conducted to examine the relationship between elevated serum CRP level and overall survival (OS) in esophageal cancer cases. Moreover, correlation analyses were conducted to assess links between pretreatment serum CRP level and tumor node metastasis (TNM) stage as well as T, N, M grade, respectively. Results: The pooled analysis showed that elevated pretreatment serum CRP level was significantly associated with poorer overall survival (HR 2.09, 95%CI 1.52-2.87, p<0.01). Subgroup analyses were conducted by "country", "cut-off value", "treatment" and "number of patients", and no single factor could alter the result. Elevated pretreatment serum CRP was significantly correlated with more advanced TNM stage and T, N, M grade respectively. Conclusions: Elevated pretreatment serum CRP levels are associated with poorer prognosis in esophageal cancer patients, and could serve as a useful biomarker for outcome prediction.

Comparison of Sampling and Analytical Methods for Determining Airborne Hexavalent Chromium -Limit of Detection, Accuracy and Precision of Analytical Procedures (공기중 6가 크롬 측정 방법 비교 -검출한계, 정확도 및 정밀도-)

  • 신용철;이병규;이지태
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.1
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    • pp.39-49
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    • 2002
  • In this study, limits of detection (LOD), accuracy and precision of four sampling/ analytical methods were evaluated and compared for the determination of airborne hexavalent chromium, Cr (VI). The methods include : (1) a combination of the National Institute for Occupational Safety and Health (NIOSH) Method 7600/U. S. Environmental Protection Agency (EPA) Method 218.6 (NIOSH/EPA Method) proposed by Shin and Paik, 2) two impinger methods using 2% NaOH/3% Na$_2$CO$_3$. (3) same as (2) but with 0.02 N NaHCO$_3$absorbing solution, and (4) the Occupational Safety and Health (OSHA) Method ID-215. An ion chromatograph/visible absorbance detector was used for the analysis of Cr (VI) in sample solution. Limit of detection (LOD) , analytical accuracy, and precision were also tested using Cr (VI) spike samples. Recoveries (as index of accuracy) and coefficient of variation (CV) (as a index of precision) were determined. Two-way ANOVA and Turkey's test were performed to test the significance in differences among recoveries and CVs of the methods. In all the methods, the peaks of Cr (VI) were separated sharply on chromatograms and exhibited a strong linearity with Cr (VI) concentrations in solution. The correlation coefficients of calibration curves typically ranged from 0.9997 to 0.9999, and the analytical LODs from 0.025 to 0.1$\mu\textrm{g}$/sample. All the method had good sensitivities and linearities between Cr (VI) levels and peak areas. The accuracies (% mean recoveries) of the methods ranged from 80.1 to 104.2%, while the precisions (pooled coefficient of variation) ranged from 3.16 to 4.43%. The impinger methods showed higher recoveries ( > 95%) than those of the PVC filter methods (the OSHA Method and the NIOSH/EPA Method). It was assumed that Cr (VI) on PVC filter was exposed to air and reduced to trivalent chromium, Cr (III), whereas it was stabilized in alkali solution contained in impinger. Thus, a special treatment of Cr (VI) samples collected on PVC filters may be required.

Association of Oral Contraceptives Use and Lung Cancer Risk among Women: an Updated Meta-analysis Based on Cohort and Case-control Studies

  • Wu, Wei;Yin, Zhi-Hua;Guan, Peng;Ren, Yang-Wu;Zhou, Bao-Sen
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.3
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    • pp.1205-1210
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    • 2014
  • Background: Previous studies on the association of oral contraceptives (OC) use and lung cancer generated inconsistent findings. The aim of this study was to confirm any definite correlation between OC use and lung cancer risk. Methods: Publications were reviewed and obtained through PubMed and EMBASE databases literature search up to November, 2013. Reference lists from retrieved articles were also reviewed. The language of publication was restricted to English. A meta-analysis was performed to evaluate the association by calculating pooled odds ratios (ORs) and 95% confidence intervals (CIs). Results: A total of 14 studies consisting of 9 case-control studies and 5 cohort studies were finally included in this meta-analysis. There was no significant association observed between OC use and lung cancer risk in the overall analysis (OR=0.91; 95% CI=0.81-1.03). There was a significant protective effect in Europe (OR=0.74; 95% CI=0.60-0.91) and a borderline significant protective effect with an adenocarcinoma histology (OR=0.90; 95% CI=0.80-1.01) in subgroup analyses. No association was observed for methodological quality of study, study design, smoking status and case number of study. Conclusion: This meta-analysis suggests that OC use is not likely to be associated with the risk of lung cancer at all. While a significant protective effect of OC use on lung cancer was observed in Europe, interpretation should be cautious because of the potential biases of low-quality studies. At the same time, more attention should be paid to the possible association of OC use with adenocarcinoma of lung. Our findings require further research, with well-conducted and large-scale epidemiological studies to confirm effects of OC use on lung cancer.

Prognosis and Clinicopathology of CXCR4 in Colorectal Cancer Patients: a Meta-analysis

  • Li, Lu-Ning;Jiang, Kai-Tong;Tan, Peng;Wang, Ai-Hua;Kong, Qing-Yin;Wang, Cui-Yue;Lu, Hua-Rong;Wang, Jing
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.4077-4080
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    • 2015
  • The chemokine receptor 4 (CXCR4) has been widely used in diagnosis and prognosis of colorectal cancer (CRC). However, there is no current consensus on the impact of CXCR4 on CRC patients. The purpose of this study was to evaluate the prognostic and clinicopathological importance of CXCR4 in CRC patients. Databases, such as PubMed, Cochrane library, CBM and EMBASE updated to 2014 were searched to include eligible articles. We analysed correlations between CXCR4 expression and clinicopathological features and overall survival (OS). A total of 1, 055 CRC patients from twelve studies were included in the study. The pooled odds ratios (ORs) which indicated CXCR4 expression was likely to be associated with TNM stage (OR=0.43, CI=0.34-0.55, P<0.00001), lymph node status (OR=2.23, CI=1.23-4.05, P=0.008) and vascular invasion (OR=2.21, CI=1.11-4.39, P=0.02). Poor overall survival of CRC cancer was found to be significantly related to CXCR4 overexpression (hazard ratio (HR) 1.36 CI=1.17-1.59, P<0.0001), whereas combined ORs revealed that CXCR4 expression had no correlation with gender or differentiation. Based on the published studies, CXCR4 overexpression in patients w ith CRC indicates poor survival outcome and clinicopathological factors.

사업 포트폴리오의 기술시너지 효과 : 50대 재벌의 패널자료분석

  • 김태유;박경민
    • Journal of Technology Innovation
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    • v.5 no.1
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    • pp.15-43
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    • 1997
  • This paper investigates empirically the relationship between various business portfolio properties (particularly technological properties) and chaebol's performance using data on the 50largest chaebols in Korea. In addition to the traditional indexes to measure diversification such as entropy index, we calculated inter-industry technological similarity using R'||'&'||'D expenditure data by industry and 1990 Input-output Table in korea, and obtained chaebol-level technological relatedness and internal transaction proportion from chaebols' business profile, inter-inustry technological similarity and 1990 input-output table. We applied factor analysis on 13 business portfolio property indexes and showed that they could be grouped into 3 dimensions. diversification scope, inter-business relatedness and degree of vertical integration. In this paper, using 50 largest chaebols' financial data (1989-1994), we analyzed empirically the effect of business portfolio properties on ROS(Return On Sales) which is conventional index for firm performance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness in not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business portfolio properties, we obtained three findings. First, only VI(Vertical integration) has a significant positive correlation with ROS. Second, when using TFP growth as an dependent variable, both TR(Technological Relatedness) and VI are significant and positively related to the dependent variable. Third, the interaction term between TR and VI is significant and negatively affects TFP growth, meaning that TR and VI are substitutes. These results suggest strategic directions on restructuring business portfolio. As VI is increased, chaebols will get more profit. A higher level of either TR or VI will increase TFP growth rate, but increase in both TR and VI will have a negative effect on TFP growth. To summarize, certain business portfolio properties such as VI and TR can be considered "resources" themselves since they can affect profit rate and productivity growth. VI and TR have a synergy effect of change in profit rate and productivity growth. VI increases ROS and productivity growth, while TR increases productivity growth representing a technological synergy effect.t.

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A Rapid, Simple Determination of Sulfur-containing Compounds and Methylmalonic Acid on Plasma using GC-MS-SIM for the Diagnosis of Homocysteinemia (혈장 중 황함유 화합물과 메틸말론산의 신속 간편한 분석법 개발; GC-MS-SIM을 이용한 호모시스테인혈증의 진단)

  • Yoon, Hye-Ran;Thapa, Maheshwor
    • Journal of The Korean Society of Inherited Metabolic disease
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    • v.15 no.3
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    • pp.138-146
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    • 2015
  • Purpose: If early diagnosis is not made, patients with metabolic disorders as homocystinemia rapidly progress to physical defect or mental retardation resulted in storage of the toxic material into the brain. Therefore, it is necessary to develop an analytical method for a rapid screening and/or correct confirmation diagnosis. Methods: The standard solution of sulfur amino acids spiked plasma was subjected to protein precipitation with methanol, and then consecutively derivatized with trimethylsilyl (TMS) and trifluoroacyl (TFA) and determined by GC-MS. The formation of TMS derivative of the hydroxyl and TFA derivative of amino functional group was performed by BSTFA and MBTFA, respectively. Selective ion monitoring (SIM) mode was used for quantification with selected specific ions. Results: A calibration curve on standard spiked pooled plasma showed a linear relationship with correlation coefficient of 0.9936-0.9992 for all compounds over the range of 0.1-300 ng. The precision and accuracy were within S.D. of 1-15% and RSD of 1-15% for intra-day assay at 2 ng/mL, 15 ng/mL and 30 ng/mL. LOD and LOQ was 0.4 ng/mL and 4 ng/mL respectively. Conclusion: A rapid analytical method was developed to quantify sulfur amino acids and methyl malonic acid, after two-step derivatization procedure with good sensitivity and specificity on human plasma. Advantages of a new method are simplicity and rapidity. The method could be useful for routine analysis, diagnosis of homocysteinemia.

근육 피로도 분석시 사용되는 매개변수들간의 민감도 비교 연구

  • 정명철;김정룡
    • Proceedings of the ESK Conference
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    • 1997.10a
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    • pp.406-413
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    • 1997
  • 근전도(EMG:Electromyogram)를 사용하여 국부 근육 피로(Localized Muscle Fatigue)를 정량화으로 분석 하기 위해 널리 이용되고 있는 AR(Autoregressive)모델의 1차 계수, RMS(Root Mean Square), ZCR(Zero Crossing Rate), MPF(Mean Power Frequency), MF(Median Frequency)를 선택하여, 근육이 발휘하는 힘과 시간의 흐름에 따라 근육 피로의 정도를 민감하게 나타내는 매개변수를 규명하였다. 피실험자 10명의 좌우 척추세움근(Erector Spinae Muscle)을 대상으로 등장수축(Sustained Isometric Contraction)조건에서 허리의 신전(Extension)운동을 실시하였다. 이때 발휘해야 하는 힘의 수준은 15%, 30%, 45%, 60%, 75% MVC 로 정하였고 각 수준마다 20초 동안 근전도를 측정하 였다. 데이터 분석은 총20초 구간의 근전도를 0.5초 간격으로 나누어 매개변수들을 각각 구하고 분석을 실시하였다. 시간의 흐름에 대한 피로도 분석 결과, AR 모델의 1차 계수와 MPF가 유의한 차이를 보였으며, 낮은 수준의 %MVC에서는 AR 계수가, 높은 수준에서는 MPF가 민감한 반응 결과를 나타냈다. 그리고 근육이 발휘하는 힘의 정도를 분석하기 위해 주로 사용되고 있는 RMS 보다는 더 AR 계수가 모든 수준에서 뚜렷하게 차이를 보인 것이 확인되었다. 따라서 AR 모델의 1차 계수가 근육의 피로 정도와 힘의 수준을 다른 매개변수에 비해 더욱 민감하게 구별함이 입증되었다. 이러한 결과는 다른 분야에서도 근육 피로를 정량적으로 측정하는데 사용될 수 있을 것으로 생각되며, 개인적 변이도를 고려한 확률 기법을 사용한다면 보다 정확한 근전도 분석이 이루어질 것으로 기대된다.있음을 알 수 있었다. 사료된다.의 결과는 자전거 에르고노미터의 결과가 트레드밀의 결과에 87.60%정도 나타났다.음을 관찰하였다. 특히 vitamin C와 E의 병용투여는 상승적으로 적용하여 간세포손상을 더욱 억제시킴을 알 수 있었다.mance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness is not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business portfolio properties, we obtained three findings. First, only VI (Vertical integration) has a significant positive correlation with ROS. Second, when using TFP growth as an dependent variable, both TR(Technological Relatedness) and f[ are signif

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승객석 Restraiant System의 구속 효과와 인체상해 연구 -어린이(6세)탑승자 중심으로-

  • 이창민
    • Proceedings of the ESK Conference
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    • 1997.10a
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    • pp.398-405
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    • 1997
  • 과거 8년간의(1985-1992) 통계에 의하면 정면과 측면 충돌시 구속 시스텡의 하나인 Airbag장착 차량의 사망자 및 중상자 수가 현저히 감소하고 있는 것으로 나타나고있다. 그 러나 최근 소비자로 부터의 Airbag에 관한 불만을 보고 받고 있다. 즉 구속효과를 발휘함에 있어 부수적으로 인체 부상을 유발하고 있다는 것이다. 사망내지는 심각한 부상은 방지하고 있으나 경미한 부상은 오히려 증가하고 또한 신체가 적은 여성 운전자나 6세 이하의 어린이 에게는 심각한 부상의 우려가 있다는 것이다. 본 연구에서는 구속시스템의 총아인 Airbag 시스템의 심각한 부수적인 부상 보고를 입증하기 위하여 우리나라 어린이 6세 신체를 기준 으로하여 구속시스템을 착용하지 않았을 경우(실제로 많은 경우), seat belt만 착용시, Airbag만 작용시, 그리고 seat belt와 Airbag을 동시에 사용할 때를 컴퓨터 Simulation Package 이용 신체 dynamic을 모의실험 하였다. 실험결과, 기존에 알려진바와 같이 구속시스템을 사용하지 않았을 경우에 부상은 매우 컸다. 신체 사이즈가 작은 어린이 혹은 여성 운전자의 경우 Seat belt만을 사용한 경우는 Airbag만을 사용한 경우보다는 부상정도가 약간 경미하였으나 두 경우 모두 인체가 구속시스템의 구속 범위를 이탈하여 구속 시스템으로써의 역할을 충분히 하지 못하고 있었다. 특히 Seat belt와 Airbag을 동시에 사용하였을시에도 Airbag이 충분히 개선된 이후라도 신체 사이즈가 작은 경우에는 흉부부위에 의한 충격 흡수가 먼저 이루어지지 못하고, 머리에 먼저 Airbag이 접촉이 되어 충격 흡수 역할보다는 반동효과가 더 커서 머리 및 몸체가 뒤로 Rebound 하는 효과로 머리, 혹은 목의 신체 부상한계를 넘고 있어 큰 부상 내지는 사망에 이르고 있음을 알 수 있었다. 사료된다.의 결과는 자전거 에르고노미터의 결과가 트레드밀의 결과에 87.60%정도 나타났다.음을 관찰하였다. 특히 vitamin C와 E의 병용투여는 상승적으로 적용하여 간세포손상을 더욱 억제시킴을 알 수 있었다.mance and on TFP(Total Factor Productivity) growth which is a pure measure of firm performance. To utilize the advantage of panel data, FEM(Fixed Effect Model) and REM(Random Effect Model) were used. The empirical result shows that the entropy index as a measurement of inter-business relatedness is not significant but technological relatedness index is significant. OLS estimates on pooled data were considerably different from FEM or REM estimates on panel data. By introducing interaction effect among the three variables for business portfolio properties, we obtained three findings. First, only VI (Vertical integration) has a significant positive correlation with ROS. Second, when using TFP growth as an dependent variable, both TR(Technological Relatedness) and f[ are significant and positively rel

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A Study on Multi-dimensional Poverty of Female Youth in Korea (우리나라 여성청년의 다차원적 빈곤에 관한 연구)

  • Yoo, Jiyoung
    • Journal of Digital Convergence
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    • v.17 no.10
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    • pp.85-91
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    • 2019
  • Present study notes that youth poverty is not only an income deficit, but also a deficit in various dimensions of life such as housing, work and health deficit. Multidimensional poverty is measured by four dimensions: income, work, housing and health. The sample is a 2630 one-person household female youth pooled from the Korea Welfare Panel 10-Year Data. The analysis tool used SPSS statistical program, and the analysis framework was the deficiency rate by dimension, the correlation analysis between deficiency dimension, and the overlapping rate of N dimension poverty. As a result, women's youth in Korea had higher deficit rate in terms of work and housing than other dimensions, and the proportion of women youth who were both poor in work and housing at the same time was also relatively higher than in other cases. Based on these results, this study proposes the construction of customized job services, job matching with small and medium-sized enterprises and allocation of one young woman's household among the targets of long-term chartered housing. Female youth's sharing-economy association should be considered as alternatives.