• Title/Summary/Keyword: Sample Size

Search Result 3,936, Processing Time 0.049 seconds

Study on the Current Situation and Issues for Clinical Research in Korean Medicine worldwide - Future Clinical Research Strategy I - (한의 임상 연구에 대한 국내외 현황 및 논쟁에 관한 고찰 - 미래 임상 연구 전략 I -)

  • Jung, Ki Yong;Go, Ho Yeon;Sun, Seung Ho;Jeong, Jong Jin;Park, Jeong Su;Song, Yun Kyung;Kim, Tae Hoon;Hong, Sung In;Choi, You Kyung;Go, Seong Gyu;Lim, Eun Mee;Lee, Choong Yeol;Park, Jong Hyeong;Jeon, Chan Yong
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.28 no.2
    • /
    • pp.137-145
    • /
    • 2014
  • The purpose of this paper is to explore the strategy of future Korean medicine(KM) clinical research through the study on the current situation and issues for KM clinical research worldwide. In this study, the papers published in English through Pubmed were investigated mainly. And we analyzed the methodological issues from the clinical research reports in the KM fields. As a result of examining the current situation of the RCTs(Randomized Controlled Trials) studies in KM, the sample size for most studies was small and the overall methodological quality appeared to be low. And there was a discussion about whether or not to apply RCTs method to the KM clinical research. The majority of studies have argued the use of RCTs method for KM clinical research. In addition, we could find some problems through the analysis of KM clinical studies. First, the majority of RCTs in KM were of low quality. Second, RCTs method was applied to the KM clinical studies according to the Western medicine methods only. Third, the actual KM diagnosis was not used in the KM studies and inadequate outcomes measurement methods were utilized without considering the characteristics of KM practice. The methodological issues in the KM clinical research were caused by the conflict between the characteristics of KM practice and clinical research method based on the western medicine.

The Exposure Status and Biomarkers of Polycyclic Aromatic Hydrocarbons in Shipyard Workers

  • Koh, Sang-Baek;Park, Jun-Ho;Yun, Ju-Song;Lee, Kang-Myoung;Cha, Bong-Suk;Chang, Sei-Jin;Kim, Cheong-Sik;Kim, Heon;Chang, Soung-Hoon
    • Molecular & Cellular Toxicology
    • /
    • v.2 no.2
    • /
    • pp.134-140
    • /
    • 2006
  • Because shipyard workers are involved with various manufacturing process in shipyard industry, and they are exposed to many kinds of hazardous materials. Especially, painting workers were exposed polycyclic aromatic hydrocarbons (PAH). This study was conducted to assess the exposure status of PAH based on job-exposure matrix. We investigated the effect of genetic polymorphism of xenobiotic metabolism enzymes involved in PAH metabolism on levels of urinary metabolite. A total of 93 shipbuilding workers were recruited in this study. Questionnaire variables were age, sex, use of personal protective equipment, smoking, drinking, and work duration. The urinary metabolite was collected in the afternoon and corrected by urinary creatinine concentration. The genotypes of CYP1A1, CYP2E1, GSTM1, GSTT1 and UGT1A6 were investigated by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods with DNA extracted from venous blood. Urinary 1-OHP levels were significantly higher in direct exposured group (spray and touch-up) than indirect exposed group. Urinary 1-OHP, concentration of the high exposure with wild type of UGT1A6 was significantlyhigher than that of the high exposure with other UGT1A6 genotype. In multiple regression analysis of urinary 1-OHP, the regression coefficient of job grade was statistically significant (p<0.05) and UGT1A6 was not significant but a trend (p<0.1). The grade of exposure affected urinary PAH concentration was statistically significant. But genetic polymorphism of xenobiotics metabolism enzymes was not statistically significant. Further investigation of genetic polymorphism with large sample size is needed.

Verification of Microstructure Qualities of ACR-Approved Mammography Phantoms by Refraction-Enhanced Synchrotron Radiation Imaging

  • Imamura, Keiko;Ehara, Norishige;Inada, Yoichi;Miyamoto, Keiko;Kanemaki, Yoshihide;Umetani, Keiji;Uesugi, Kentaro;Ochiai, Yoshinori;Fukuda, Mamoru;Nakajima, Yasuo
    • Proceedings of the Korean Society of Medical Physics Conference
    • /
    • 2002.09a
    • /
    • pp.415-417
    • /
    • 2002
  • Images of microcalcification specks showed large variation in conventional radiographs of phantoms which are approved for mammography image quality standard by the American College of Radiology (ACR). This kind of variation is not appropriate for image quality standards because the number of specks are visually counted in images and that number is important in image quality evaluation. Our study using synchrotron radiation (SR) imaging revealed the overlapping of micro-sized air bubble(s) to some specks, and also the structural deformation or crackings. Eight phantoms approved by ACR from two different makers and an air-bubble phantom were examined. SR imaging was performed at a synchrotron radiation facility, SPring-8, in Japan. The image-detector was a fluorescent-screen optical-lens coupling system using a CCD camera with a spatial resolution of 6 $\square$m. Objects when imaged with longer sample-to-detector distance show edge enhancement due to a difference in refraction indices, that is refraction enhancement. Refraction-enhanced SR images revealed that some of specks carried foreign objects, which were proven to be air. In phantoms provided by one maker, attaching/overlapping airs were observed for 62 out of 150 specks (41%) , with a higher incidence for the smallest specks. A speck becomes hardly visible in a conventional radiograph when air(s) overlaps the majority part of a speck, though depending on the size of the air-inclusion and on its configuration. Those airs might have been adsorbed on a speck surface before being embedded and then introduced into the matrix together with specks. Our study using SR imaging has clearly shown the nature of defects in some mammography phantoms which seriously degrade the quality as an image standard.

  • PDF

A Comparative Study on Medical Utilization between Urban and Rural Korea (도시 농촌간 의료이용 수준의 비교분석)

  • Joo, Kyung-Shik;Kim, Han-Joong;Lee, Sun-Hee;Min, Hye-Young
    • Journal of Preventive Medicine and Public Health
    • /
    • v.29 no.2 s.53
    • /
    • pp.311-329
    • /
    • 1996
  • This study was designed to compare the level of medical utilization between the urban and rural areas of Korea and to explain the differences between the two regions. Data from the National Health Interview Survey performed by the Korean Institute of Health & Social Affairs in 1992 were used for this study utilizing a sample size of 21,841 people. The level of medical utilization such as the number of physician visits and the number of hospital admissions was compared between the regions with ANOVA. Various determinants for medical use were also compared by univariate analysis. Statistical models which included enabling factors, predisposing factors, need factors and region were constructed for bivariate analysis in order to further elucidate the level of medical utilization. The results were as follows: 1. There was greater medical use, both in terms of physician visits and inpatient care in the rural areas in spite of insufficient health resources. The particular reasons for higher medical utilization in rural areas were attributed to a higher number of initial physician visits as well as a longer the length of stay per hospital admission. Therefore, indicators representing the degree of met need (utilization/need) showed no significant difference between rural and urban areas in spite of the fact that the medical need is larger in rural areas. 2. Use of public health facilities received a significant portion of physician visits in the rural area. The government's effort to enhance primary health care through health centers, health subcenters and the nurse practitioner's post in rural areas has contributed to the increase of access to medical care in the rural areas. 3. There were some differences in the socio-demographic characteristics between two regions ; There were more elderly people over the age of 65: unstable marital status, less education and lower incomes also characterized the rural areas. Therefore, among rural people, there were more predisposing factors for medical use. Additionaly, need factors such as poor self-reported health status and high morbidity level were also high in the rural area. 4. In contrast it was learned that, the supply of health resources was mostly concentrated in the urban areas except for public health facilities. Therefore, geographical access to medical care was lower in the rural area both in terms travel time and travel cost. 5. The coefficient of the region variable was insignificant in the regression model which controlled the supply factor only. However, utilization was significantly higher in urban areas if the model included predisposing factors and need factors in addition to the supply factor. The results were interpreted as rural people have greater medical needs.

  • PDF

Investigation on CO Adsorption and Catalytic Oxidation of Commercial Impregnated Activated Carbons (상용 첨착활성탄의 일산화탄소 흡착성능 및 촉매산화반응 연구)

  • Ko, Sangwon;Kim, Dae Han;Kim, Young Dok;Park, Duckshin;Jeong, Wootae;Lee, Duck Hee;Lee, Jae-Young;Kwon, Soon-Bark
    • Applied Chemistry for Engineering
    • /
    • v.24 no.5
    • /
    • pp.513-517
    • /
    • 2013
  • We investigated the properties of impregnated activated carbons, a commercial adsorbent for the individual protection equipment, and examined CO adsorption and oxidation to $CO_2$. The surface area, pore volume and pore size were measured for four commercial samples using Brunauer-Emmett-Teller/Barrett-Joyner-Halenda (BET/BJH), and atomic compositions of the sample surface were analyzed based on SEM/EDS and XPS. Impregnated activated carbons containing Mn and Cu for fire showed the catalytic CO oxidation to $CO_2$ with a high catalytic activity (up to 99% $CO_2$ yield), followed by the CO adsorption at an initial reaction time. On the other hand, C: for chemical biologial and radiological (CBR) samples, not including Mn, showed a lower CO conversion to $CO_2$ (up to 60% yield) compared to that of fire samples. It was also found that a heat-treated activated carbon has a higher removal capacity both for CO and $CO_2$ at room temperature than that of untreated carbon, which was probably due to the impurity removal in pores resulted in a detection-delay about 30 min.

Ki67 Frequency in Breast Cancers without Axillary Lymph Node Involvement and its Relation with Disease-free Survival

  • Shandiz, Fatemeh Homaei;Shabahang, Hossein;Afzaljavan, Fahimeh;Sharifi, Nourieh;Tavasoli, Alireza;Afzalaghaee, Monavar;Roshanzamir, Emane;Pasdar, Alireza
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.3
    • /
    • pp.1347-1350
    • /
    • 2016
  • Background: Breast cancer prognosis is influenced by several histopathology and clinical factors including expression of Ki67 which may have a predictive role in lymph node negative breast cancer patients. The aim of this study was to assess Ki67 expression in breast cancers without axillary lymph node involvement and to evaluate its prognostic value with regard to disease-free survival. Materials and Methods: Subjects were selected from non-metastatic invasive breast cancer patients who were referred to the oncology department of Ghaem hospital during 1 April 2001 to 1 April 2008. Ki67 levels were measured using immunohistochemistry (IHC) and compared with clinicopathological features. The relation of Ki67 expression with disease-free survival was also analysed. Results: A total of 106 women with a mean age of 49 were examined. Some 94.3% were classified as having invasive ductal carcinomas and the mean tumour diameter at the time of diagnosis was 2.8 cm. Some 50.9% of cases were ER positive and 47.2% were PR positive. P53 expression was positive in 48.1% of the cases. According to the IHC results, only 8.5% of the patients were Her2/neu positive. Ki67 was positive in 66 (62.3%) with a significant relation to lower age (p=0.0229) and P53 positivity (p=0.005). After an average of 40-months follow up, 13 (12.3%) demonstrated recurrence, most commonly systemic. Of 13 cases with relapse, 10 patients (77%) were Ki67 positive. Conclusions: In our population Ki67 appeared to be an independent prognostic factor for three-year survival. However, we stress that a survival study with a bigger sample size would help to support this conclusion.

Association of XRCC3 Thr241Met Polymorphisms and Gliomas Risk: Evidence from a Meta-analysis

  • Liang, Hong-Jie;Yan, Yu-Lan;Liu, Zhi-Ming;Chen, Xu;Peng, Qi-Liu;Wang, Jian;Mo, Cui-Ju;Sui, Jing-Zhe;Wu, Jun-Rong;Zhai, Li-Min;Yang, Shi;Li, Tai-Jie;Li, Ruo-Lin;Li, Shan;Qin, Xue
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.7
    • /
    • pp.4243-4247
    • /
    • 2013
  • The relationship between the X-ray repair cross-complementing group 3 (XRCC3) Thr241Met polymorphism and gliomas remains inclusive or controversial. For better understanding of the effect of XRCC3 Thr241Met polymorphism on glioma risk, a meta-analysis was performed. All eligible studies were identified through a search of PubMed, Elsevier Science Direct, Excerpta Medica Database (Embase) and Chinese Biomedical Literature Database (CBM) before May 2013. The association between the XRCC3 Thr241Met polymorphism and gliomas risk was conducted by odds ratios (ORs) and 95% confidence intervals (95% CIs). A total of nine case-control studies including 3,533 cases and 4,696 controls were eventually collected. Overall, we found that XRCC3 Thr241Met polymorphism was significantly associated with the risk of gliomas (T vs. C: OR=1.10, 95%CI=1.01-1.20, P=0.034; TT vs. CC: OR=1.30, 95%CI=1.03-1.65, P=0.027; TT vs. TC/CC: OR=1.29, 95%CI=1.01-1.64, P=0.039). In the subgroup analysis based on ethnicity, the significant association was found in Asian under four models (T vs. C: OR=1.17, 95%CI=1.07-1.28, P=0.00; TT vs. CC: OR=1.79, 95%CI=1.36-2.36, P=0.00; TT vs. TC/CC: OR=1.75, 95%CI=1.32-2.32, P=0.00; TT/TC vs. CC: OR=1.11,95% CI=1.02-1.20). This meta-analysis suggested that the XRCC3 Thr241Met polymorphism is a risk factor for gliomas, especially for Asians. Considering the limited sample size and ethnicities included in the meta-analysis, further large scale and well-designed studies are needed to confirm our results.

B-cell Lymphoma 2 rs17757541 C>G Polymorphism was Associated with an Increased Risk of Gastric Cardiac Adenocarcinoma in a Chinese Population

  • Li, Qiong;Yin, Jun;Wang, Xu;Wang, Li-Ming;Shi, Yi-Jun;Zheng, Liang;Tang, Wei-Feng;Ding, Guo-Wen;Liu, Chao;Liu, Rui-Ping;Gu, Hai-Yong;Sun, Jia-Ming;Chen, Suo-Cheng
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.7
    • /
    • pp.4301-4306
    • /
    • 2013
  • Aim: Apoptosis has been considered as a fundamental component in cancer pathogenesis, and related genetic factors might play an important role in gastric cardiac adenocarcinoma (GCA) genesis. Methods: We conducted a hospital based case.control study to evaluate the genetic effects of functional single nucleotide polymorphisms (SNPs): BCL2 rs17757541 C>G, BCL2 rs12454712 T>C, FAS rs2234767 G>A, FASL/FASLG rs763110 C>T, ERBB2 rs1136201 A>G and VEGFR2/KDR rs11941492 C>T on the development of GCA. A total of 243 GCA cases and 476 controls were recruited for the study and genotypes were determined using a custom-by-design 48-Plex SNPscan$^{TM}$ Kit. Results: The BCL2 rs17757541 C>G polymorphism was associated with increased risk of GCA. However, there was no significant associations with the other five SNPs. Stratified analyses indicated a significantly increased risk of GCA associated with the BCL2 rs17757541 C>G polymorphism among males, older patients and those with a history of smoking or drinking. Conclusion: These findings indicated that the functional polymorphism BCL2 rs17757541 C>G might contribute to GCA susceptibility. However, our results were limited by small sample size. Future larger studies are required to confirm our current findings.

A Study on the Export Potential of Bangladesh's Ready-Made Garments (중력모형을 이용한 방글라데시 의류 유망 수출시장 추정)

  • Hossain, Sumon;Oh, Keunyeob
    • Management & Information Systems Review
    • /
    • v.37 no.2
    • /
    • pp.87-108
    • /
    • 2018
  • This article explores the international trade flow of Bangladesh's ready-made garments (RMG). We first suggest the brief history and an international structure of trade among countries by using the trade volume. Then we implemented a gravity model regression with the sample of 38 major partner countries in order to investigate the potential export market for the RMG industry. The fixed effect and random effect model for the panel data during the period of 1990 to 2011 are estimated. Our result shows that Bangladesh's RMG exports are affected positively by the size of economy, inflation, exchange rate, foreign direct investment(FDI) and trade openness. On the other hand, the distance between trading partners are related negatively with the trade volume. We used the estimated coefficients from the panel regression in order to predict RMG export potential of Bangladesh. This might show which country is the promising export market for Bangladesh RMG industry. We found that Bangladesh has the highest potential of RMG export with Japan and USA, which seem to have considerable room for export growth if trade barriers and constraints are removed. We added some policy implications for encouraging the RMG export of Bangladesh by using the results from the analysis.

Annealing Effects on Al0.2CoFe1.8O4 Ferrite Film and Powder (Sol Gel 방법으로 제조한 Al0.2CoFe1.8O4 분말과 박막의 열처리 효과)

  • Chae, Kwang-Pyo;Lee, Jae-Gwang;Kweon, Hyuck-Su;Kim, Jung-Hoon;Lee, Young-Bae
    • Journal of the Korean Magnetics Society
    • /
    • v.15 no.3
    • /
    • pp.186-190
    • /
    • 2005
  • The $Al_{0.2}CoFe_{1.8}O_4$ ferrite films and powders were prepared by the sol-gel method. The crystallographic and magnetic properties of the samples were examined with annealing temperature by X-ray diffraction, $M\ddot{o}ssbauer$ spetroscopy and vibrating sample magnetometry. The powder samples showed the presence of spinel structure at annealing temperatures above 673 K, while the film samples indicated the spinel structure above 873 K, also the particle size increased with rising annealing temperatures. The $M\ddot{o}ssbauer$ spectra of $Al_{0.2}CoFe_{1.8}O_4$ powder annealed above 873 K could be fitted as the superposition of two Zeeman sextets due to ferrimagnetic phase. And the spectra of annealed at 673 K exhibited the superposition of ferrimanetic and paramagnetic phase and those of annealed at 473 K showed only a paramagnetic phase. The magnetic behaviour of powders appeared that the coercivity increased until annealed at 673 K but decreased above this temperature. The coercivity of the film samples decreased from 1.084 kOe at 873 K to 0.540 kOe at 1073 K with increasing annealing temperatures.