• 제목/요약/키워드: case-control studies

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ADHD의 한약물 치료에 대한 최신 임상연구 동향 -2007년부터 2012년까지 중국 논문을 중심으로- (The Current State of Clinical Studies for Herbal Medicine of Attention Deficit Hyperactivity Disorder (ADHD) -Focusing on Chinese Journals-)

  • 유춘길;조아람;서주희;정성식;이지수;성우용
    • 동의신경정신과학회지
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    • 제24권1호
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    • pp.1-12
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    • 2013
  • Objectives : The purpose of this study was to take around herbal medicine for Attention Deficit Hyperactivity Disorder in China. Methods : A journal search was performed using China National Knowledge Infrastructure (CNKI) from 2007 to 2012. Key words searched were 'ADHD'. Results : 25 studies were selected. Case control studies showed that herbal medicine treatment reported better results than the western medicine treatment group. 12 case reports reported a significant improvement in herbal medicine treatment for patients with ADHD. Frequently used herbal materials were Rhizome of Polygalae Radix and Rhizome of Acori Gramineri Rhizoma (16 times), Root of Glycyrrhiza uralensis Fisch (14 times), Root of Rehmanniae Radix et Rhizoma Preparata and Sclerotium of Poria cocos Wolf (12 times). Conclusions : There have been many studies regarding herbal medicine for Attention Deficit Hyperactivity Disorder in China, and these studies can be applied to the clinical practices in Korea.

Performance Tradeoff Between Control Period and Delay: Lane Keeping Assist System Case Study

  • Cha, Hyun-Jun;Park, Seong-Woo;Jeong, Woo-Hyuk;Kim, Jong-Chan
    • 한국컴퓨터정보학회논문지
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    • 제20권11호
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    • pp.39-46
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    • 2015
  • In this paper, we propose a performance-aware workload model for efficient implementation of control systems. When implementing a control algorithm as an embedded computer system, the control code executes periodically. For such systems, its control performance depends on not only the accuracy of the control algorithm itself but also temporal parameters such as control period and sensing to actuation delay. In this regard, this paper studies the relation between control period and delay by measuring and analyzing the control performance of LKAS (Lane Keeping Assist System) with varying period and delay combinations. Through this experimental study, this paper shows that the two timing parameters, i.e.,control period and delay, has a tradeoff relation in terms of control performance.

한의학임상에 기초를 둔 천연물신약 연구과정에 대한 소고 - 역사적 근거 발굴부터 천연물신약 임상시험계획승인신청까지 - (A Proposal for Research Process of Botanical Drug based Clinical Traditional Korean Medicine - Historical Evidence-Based Medicine II -)

  • 엄석기;김세현;김경석;박상재;어완규;최원철
    • 대한한의학원전학회지
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    • 제23권4호
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    • pp.63-102
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    • 2010
  • Purpose : To propose various types of clinical research which is feasible for botanical new drug (IND) development processes, and suggest essential steps to development of study protocol for IND. Methods : Literature-based discussions and one research group's experience is given regarding domestic act, regulation, and system. Results : In order to get an approval of IND for botanical drug in Korea there are several types of clinical research to conduct. In quality control steps for standardized medicinal herbs, case reports or case series can be conducted, and for good manufacturing practice(GMP) steps, we can conduct case reports, case series, and retrospective cohort studies. In addition, as long as we gathered good laboratory practice(GLP) data we can conduct up to quasi-experimental studies and clinical trials including investigator initiated trials. In order to conduct these studies development of study protocol is essential. First, we obtain historical evidence including target disease and indication, efficacy, safety, and endpoints by reviewing medical classics. Second, we obtain clinically and statistically important data by conducting non-clinical studies, observation studies, and quasi-experimental studies. Third, we generate research hypotheses and purposes and explore methodologies, endpoints, clinical practice guidelines, cost-effectiveness, and commercial potential. Finally, we develop study protocol with aid of biostatistician or expert in contract research organization. Discussions and conclusions : This study have obvious limitations in that most thoughts, suggestions, and proposes are from one research group's experience. Therefore, we hope to see various types of research in this topic and process from other research group as well.

Association between Cigarette Smoking and RASSF1A Gene Promoter Hypermethylation in Lung Cancer Patients: a Meta-analysis

  • Wu, Xiao-Ming;Chen, Yu;Shao, Yang;Zhou, Xiao-Long;Tang, Wen-Ru
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권19호
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    • pp.8451-8454
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    • 2014
  • Objectives: Epidemiological studies have shown that molecular mechanisms underlying the development of lung cancers differ between smokers and unsmokers. Aberrant promoter methylation in some tumor suppressor genes is frequent in lung tumors from smokers but rare in those from non-smokers. Recently, many studies have investigated the association between cigarette smoking and RASSF1A gene promoter hypermethylation in lung cancer patients, but a unanimous conclusion could not be reached. We therefore performed this meta-analysis to derive a more precise estimation of any association. Study Design: An electronic search of PubMed and Chinese Biomedicine databases was conducted to select studies. A total of 19 case-control studies were chosen, and odds ratios (ORs) with confidence intervals (CIs) were used to assess the strength of associations. Results: The case-control studies covered 2, 287 lung cancer patients: 63.4%(1449) of the patients were smokers, 36.6% (838) were unsmokers. The overall results suggested that smokers with lung cancer had a 1.297-fold (95% CI: 1.066~1.580, p=0.010, p=0.087) higher risk for RASSF1A gene hypermethylation than the non-smokers. In the stratified analysis, an increased risk of RASSF1A gene hypermethylation in smokers than in non-smokers was found in Asian (OR=1.481, 95%CI: 1.179~1.861, p=0.001, p=0.186). Conclusions: This meta-analysis supports the idea that RASSF1A gene hypermethylation is associated with cigarette smoking-induced lung cancer.

Evaluation of Methods to Analyze SNP-based Association Studies in a DNA-Pooling Experiment with Preferential Amplification

  • Ahn, Chul;Lee, Kyu-Sang
    • 한국생물정보학회:학술대회논문집
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    • 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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    • pp.395-398
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    • 2005
  • Genetic association case-control studies using DNA pools are efficient ways of detecting association between a marker allele and disease status. DNA pooling is an efficient screening method for locating susceptibility genes associated with the disease. However, DNA pooling is efficient only when allele frequency estimation is done precisely and accurately. Through the evaluation of empirical type I errors and empirical powers by simulation, we will evaluate the methods that correct for preferential amplification of nucleotides when estimating the allele frequency of single-nucleotide polymorphisms.

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계량형 샘플링 검사에서의 경험적 베이즈 추정 (Empirical Bayes Estimation on Sampling Inspection by Variables)

  • 신민웅;신기일
    • 품질경영학회지
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    • 제23권3호
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    • pp.45-56
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    • 1995
  • The method of lot by lot quality protection for sampling inspection by variables is widely used in quality control. In case of sampling inspection being done repeatedly, one can use the information from the previous sampling inspection to improve current estimates. This article shows that empirical Bayes estimator is superior to the usual sample mean in repeated sampling inspection by variables.

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The -765G>C Polymorphism in the Cyclooxygenase-2 Gene and Digestive System Cancer: a Meta-analysis

  • Zhao, Fen;Cao, Yue;Zhu, Hong;Huang, Min;Yi, Cheng;Huang, Ying
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권19호
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    • pp.8301-8310
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    • 2014
  • Background: Published data regarding associations between the -765G>C polymorphism in cyclooxygenase-2 (COX-2) gene and digestive system cancer risk have been inconclusive. The aim of this study was to comprehensively evaluate the genetic risk of the -765G>C polymorphism in the COX-2 gene for digestive system cancer. Materials and Methods: A search was performed in Pubmed, Medline (Ovid), Embase, CNKI, Weipu, Wanfang and CBM databases, covering all studies until Feb 10, 2014. Statistical analysis was performed using Revman5.2. Results: A total of 10,814 cases and 16,174 controls in 38 case-control studies were included in this meta-analysis. The results indicated that C allele carriers (GC+CC) had a 20% increased risk of digestive system cancer when compared with the homozygote GG (odds ratio (OR)=1.20, 95% confidence interval (CI), 1.00-1.44 for GC+CC vs GG). In the subgroup analysis by ethnicity, significant elevated risks were associated with C allele carriers (GC+CC) in Asians (OR = 1.46, 95% CI=1.07-2.01, and p=0.02) and Africans (OR=2.12, 95% CI=1.57-2.87, and p< 0.00001), but not among Caucasians, Americans and mixed groups. For subgroup analysis by cancer type (GC+CC vs GG), significant associations were found between the -765G>C polymorphism and higher risk for gastric cancer (OR=1.64, 95% CI=1.03-2.61, and p=0.04), but not for colorectal cancer, oral cancer, esophageal cancer, and others. Regarding study design (GC+CC vs GG), no significant associations were found in then population-based case-control (PCC), hospital-based case-control (HCC) and family-based case-control (FCC) studies. Conclusions: This meta-analysis suggested that the -765G>C polymorphism of the COX-2 gene is a potential risk factor for digestive system cancer in Asians and Africans and gastric cancer overall.

비-어파인 비선형 동특성을 갖는 무인 자율 이동 보트의 속도 제어를 위한 적응 퍼지 제어 계통 (An Adaptive Fuzzy Control System for the Speed Control of the Autonomous Surface Vehicle with Nonaffine Nonlinear Dynamics)

  • 박영환;이재경
    • 제어로봇시스템학회논문지
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    • 제18권1호
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    • pp.1-6
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    • 2012
  • In this paper, an adaptive fuzzy control system is proposed for the speed control of the ASV (Autonomous Surface Vehicle) with nonaffine nonlinear system dynamics. We consider the turning speed of the screw propeller to be the control input instead of thrust so that we do not have to know the exact function between turning speed and thrust. But in this case, the ASV becomes a nonaffine nonlinear system because thrust is a nonlinear function of the turning speed. To solve this problem, we propose a Takagi-Sugeno fuzzy-model-based control system and simulation studies are performed. Simulation results show the effectiveness of the proposed control scheme.

클린룸 제조공정에서 수율개선을 위한 입자오염제어 방법 (Method of Particle Contamination Control for Yield Enhancement in the Cleanroom)

  • 노광철;이현철;김대영;오명도
    • 대한기계학회논문집B
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    • 제31권6호
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    • pp.522-530
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    • 2007
  • The practical studies on the method of particle contamination control for yield enhancement in the cleanroom were carried out. The method of the contamination control was proposed, which are composed of data collection, data analysis, improvement action, verification, and implement control. The partition check method and the composition analysis for data collection and data analysis were respectively used in the main board and the cellular phone module production lines. And these methods were evaluated by the variation of yield loss between before and after improvement action. In case that the partition check method was applied, the critical process step was selected and yield loss reduction through improvement actions was observed. While in case that the composition analysis was applied, the critical sources were selected and yield loss reduction through improvement actions was also investigated. From these results, it is concluded that the partition check and the composition analysis are effective solutions for particle contamination control in the cleanroom production lines.

자기베어링으로 지지된 연삭 스핀들의 런아웃 제어 -LMS Feedforward 제어를 이용한 실험적 해석- (Runout Control of Mgenetically Suspended Grinding Spindle - Experimental Analysis of Adaptive LMS Feedforward Control Method -)

  • 노승국;경진호;박종권;최언돈
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 추계학술대회 논문집
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    • pp.997-1001
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    • 2000
  • In this paper, the case studies of reducing rotational errors is theoretically done for a grinding spindle with an active magnetic bearing system. The rotational errors acting on the magnetic bearing spindle are due to mass unbalance of rotor, runout, grinding excitation and unmodeled nonlinear dynamics of electromagnets. For the most case, the electrical runout of sensor target is big even in well finished surface, this runout can cause a rotation error amplified by feedback control system. The adaptiveed forward method based on LMS algorithm is discussed to compensate this kind of runout effects, and investigated its effectiveness by numerical simulation and experimental analysis. The electrical runout form the rear sensor target of grind spindle is about 70$\mu\textrm{m}$ with harmonic frequencies. The rotor orbit size in rear bearing is reduced about to 5$\mu\textrm{m}$ due to 1X and 2X rejection by feedforward control.

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