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Periodontal disease is associated with increased coronary heart disease risk:A meta-analysis based on 38 case-control studies 被引量:1
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作者 Wei-Dong Leng Xian-Tao Zeng +2 位作者 Yong-Ji Chen Zhong-Qun Zhan Yong Yang 《World Journal of Meta-Analysis》 2013年第1期47-56,共10页
AIM: To investigate whether periodontal disease(PD) is associated with increasing coronary heart disease(CHD) risk by performing a meta-analysis.METHODS: Two authors independently searched Pub Med and China National K... AIM: To investigate whether periodontal disease(PD) is associated with increasing coronary heart disease(CHD) risk by performing a meta-analysis.METHODS: Two authors independently searched Pub Med and China National Knowledge Infrastructure up to January 10 th, 2013 for relevant case-control studies that investigated the association between PD and CHD. After quality assessment using Newcastle-Ottawa Scale and data extraction by two independent authors, the overall and subgroup meta-analyses were performed and publication bias were examined using the Comprehensive Meta-Analysis V2 software. Potential publication bias was assessed using visual inspection of the funnel plots, Egger linear regression test, and trims and fill method.RESULTS: Finally 38 relevant case-control studies were identified, involving 4950 CHD patients and 5490 controls. Eleven studies were rated low quality and 27 were high quality. Based on random-effects, a significant association was identified between PD and CHD(OR 3.79, 95%CI: 2.23-6.43, P < 0.001, I2 = 98.59%), and sensitivity analysis showed that this result was robust. Subgroup analyses according to adjusted/unadjusted ORs, source of control, methodological quality, end point, assessment of PD/CHD, and ethnicity also indicated a significant association. Publication bias was detected, and the estimated OR including the "missing" studies did not substantially differ from our estimate with adjustment for missing studies(OR 4.15, 95%CI: 2.62-6.54, P < 0.001).CONCLUSION: Based on the meta-analysis, PD is probably associated with CHD risk independently and significantly. 展开更多
关键词 Periodontal disease Coronary heart disease Case-control study Risk factor META-ANALYSIS
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Study design in evidence-based surgery:What is the role of case-control studies?
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作者 Amy M Cao Michael R Cox Guy D Eslick 《World Journal of Methodology》 2016年第1期101-104,共4页
Randomized controlled trials(RCTs) are the gold standard in terms of study design, however, in the surgical setting conducting RCTs can often be unethical or logistically impossible. Case-control studies should become... Randomized controlled trials(RCTs) are the gold standard in terms of study design, however, in the surgical setting conducting RCTs can often be unethical or logistically impossible. Case-control studies should become the major study design used in surgical research when RCTs are unable to be conducted and definitely replacing case series which offer little insight into surgical outcomes and disease processes. 展开更多
关键词 Research studies CASE-control studies RANDOMIZED CLINICAL trials BIAS SAMPLE size
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Studies on high-yielding cultivation of rice in Guangdong by diagnosis and control of chlorophyll content and LAI
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作者 LIN Xiuzhen HUANG Qiumei TU Zengping Rice Research Institute,Guangdong Academy of Agricultural Sciences(GAAS),Guangzhou 510640,China 《Chinese Rice Research Newsletter》 1991年第2期4-6,共3页
During the 1970’s and 1980’s studies on the rela-tion between LAI and yield had been carried out inGAAS.The main results were as follows:(1)Usingthe accumulated LAI value at three stages,i.e.panicle initiation(PI),h... During the 1970’s and 1980’s studies on the rela-tion between LAI and yield had been carried out inGAAS.The main results were as follows:(1)Usingthe accumulated LAI value at three stages,i.e.panicle initiation(PI),heading(H)and 20 d afterheading(H),to analyze the relation between LAIand yield was more accurrate than only using theLAI value at H stage(see table);(2)Reaching cer- 展开更多
关键词 studies on high-yielding cultivation of rice in Guangdong by diagnosis and control of chlorophyll content and LAI high
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Selected elements of rock burst state assessment in case studies from the Silesian hard coal mines 被引量:4
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作者 KABIESZ Józef MAKóWKA Janusz 《Mining Science and Technology》 EI CAS 2009年第5期660-667,共8页
Exploitation of coal seams in the Upper Silesian Coal Basin is conducted in complex and difficult conditions. These difficulties are connected with the occurrence of many natural mining hazards and limitations resulti... Exploitation of coal seams in the Upper Silesian Coal Basin is conducted in complex and difficult conditions. These difficulties are connected with the occurrence of many natural mining hazards and limitations resulting from the existing in this area surface infrastructure. One of the most important problems of Polish mining is the rock burst hazard and reliable evaluation of its condition. During long-years’ mining practice in Poland a comprehensive system of evaluation and control of this hazard was developed. In the paper the main aspects of rock burst hazard state evaluation will be presented, comprising: 1) rock mass inclination for rock bursts, i.e., rock strength properties investigation, comprehensive parametric evaluation of rock mass inclination for rock bursts, prognosis of seismic events induced by mining operations, methods of computer-aided modelling of stress and rock mass deformation parameters distribution, strategic rock mass classification under rock burst degrees; 2) immediate seismic and rock burst hazard state evaluation, i.e., low diameter test drilling method, seismologic and seismoacoustic method, comprehensive method of rock burst hazard state evaluation, non-standard methods of evaluation; 3) legal aspects of rock burst hazard state evaluation. Selected elements of the hazard state evaluation system are illustrated with specific practical examples of their application. 展开更多
关键词 coal mine rock bursts control case studies
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Agent-Based Simulation for Interconnection-Scale Renewable Integration and Demand Response Studies
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作者 David P.Chassin Sahand Behboodi +1 位作者 Curran Crawford Ned Djilali 《Engineering》 SCIE EI 2015年第4期422-435,共14页
This paper collects and synthesizes the technical requirements, implementation, and validation methods for quasi-steady agent-based simulations of interconnectionscale models with particular attention to the integrati... This paper collects and synthesizes the technical requirements, implementation, and validation methods for quasi-steady agent-based simulations of interconnectionscale models with particular attention to the integration of renewable generation and controllable loads. Approaches for modeling aggregated controllable loads are presented and placed in the same control and economic modeling framework as generation resources for interconnection planning studies. Model performance is examined with system parameters that are typical for an interconnection approximately the size of the Western Electricity Coordinating Council(WECC) and a control area about 1/100 the size of the system. These results are used to demonstrate and validate the methods presented. 展开更多
关键词 interconnection studies demand response load control renewable integration agent-based simulation electricity markets
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A Preliminary Outline of the Statistical Inference Process in Genetic Association Studies 被引量:1
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作者 Tapati Basak Nipa Roy 《Open Journal of Statistics》 2022年第2期200-209,共10页
The genome-wide association study (GWAS) is a powerful experimental design that is applied to detect disease susceptible genetic variants. The main goal of these studies is to provide a better understanding of the bio... The genome-wide association study (GWAS) is a powerful experimental design that is applied to detect disease susceptible genetic variants. The main goal of these studies is to provide a better understanding of the biology of disease, which further facilitates prevention or better treatment. A statistical inferential process is finally carried out in this study, where an association is usually observed between the single-nucleotide polymorphism (SNPs) and the traits in a case-control setting. To detect the disease responsible loci correctly, the investigation of the statistical association should be carefully conducted along with the other necessary steps. This research provides an introductory guideline for conducting such statistical association tests for these studies using SNP genotype data. 展开更多
关键词 GWAS Statistical Inference ASSOCIATION SNP Case-control Study
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Effect of Jianpi Shengxue Tablet on Iron Metabolism and Nutritional Status in Patients with Renal Anemia:A Prospective,Randomized,Open,Parallel Controlled and Multicenter Clinical Study
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作者 Juan YANG Meng-yuan LIANG +15 位作者 Yu LI Hao ZHANG Wei LI Jing LV Li-ping DONG Jing-song JIN Cheng YANG Qing-hong ZHANG Li LONG Rong ZOU Yi GAO Dan SONG Chun-qin PAN Ying YAO Xiao-lin ZHAN Xiao-hui WANG 《Current Medical Science》 SCIE CAS 2024年第3期603-610,共8页
Objective This study aimed to analyze the clinical efficacy of the Jianpi Shengxue tablet for treating renal anemia.Methods A total of 200 patients with renal anemia from December 2020 to December 2022 were enrolled a... Objective This study aimed to analyze the clinical efficacy of the Jianpi Shengxue tablet for treating renal anemia.Methods A total of 200 patients with renal anemia from December 2020 to December 2022 were enrolled and randomly divided into two groups.Patients in the control group were treated with polysaccharide-iron complex,and those in the experimental group were administered Jianpi Shengxue tablet.After 8 weeks of continuous treatment,the therapeutic outcomes regarding anemia were compared between the two groups.Results After treatment,the red blood cell(RBC)count,hematocrit(HCT),reticulocyte percentage(RET),ferritin(SF),serum iron(SI),transferrin saturation(TSAT),and serum albumin(ALB)all increased(P<0.01),and the clinical symptom score and total iron binding capacity decreased(P<0.01)in the experimental group.Moreover,the improvements in RBC,HCT,RET,SF,SI,TAST,ALB,and clinical symptoms(fatigue,anorexia,dull skin complexion,numbness of hands and feet)in the experimental group were significantly greater than those in the control group(P<0.05).The total effective rate for treating renal anemia was significantly higher in the experimental group than in the control group(P<0.01).Conclusion The Jianpi Shengxue tablet demonstrates efficacy in treating renal anemia,leading to significant improvements in the laboratory examination results and clinical symptoms of patients with renal anemia. 展开更多
关键词 Jianpi Shengxue tablet renal anemia RANDOMIZED OPEN parallel control multicenter clinical study
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Effects of Lycium barbarum polysaccharide on cytokines in adolescents with subthreshold depression:a randomized controlled study
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作者 Xiaoyue Li Tao Liu +6 位作者 Xuan Mo Runhua Wang Xueyan Kong Robin Shao Roger S.Mclntyre Kwok-Fai So Kangguang Lin 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期2036-2040,共5页
Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses.Moreover,anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms.Lyci... Strong evidence has accumulated to show a correlation between depression symptoms and inflammatory responses.Moreover,anti-inflammatory treatment has shown partial effectiveness in alleviating depression symptoms.Lycium barbarum polysaccharide(LBP),derived from Goji berries,exhibits notable antioxidative and anti-inflammatory properties.In our recent double-blinded randomized placebo-controlled trial,we found that LBP significantly reduced depressive symptoms in adolescents with subthreshold depression.It is presumed that the antidepressant effect of LBP may be associated with its influence on inflammatory cytokines.In the double-blinded randomized controlled trial,we enrolled 29 adolescents with subthreshold depression and randomly divided them into an LBP group and a placebo group.In the LBP group,adolescents were given 300 mg/d LBP.A 6-week follow up was completed by 24 adolescents,comprising 14 adolescents from the LBP group(15.36±2.06 years,3 men and 11 women)and 10 adolescents from the placebo group(14.9±1.6 years,2 men and 8 women).Our results showed that after 6 weeks of treatment,the interleukin-17A level in the LBP group was lower than that in the placebo group.Network analysis showed that LBP reduced the correlations and connectivity between inflammatory factors,which were associated with the improvement in depressive symptoms.These findings suggest that 6-week administration of LBP suppresses the immune response by reducing interleukin-17A level,thereby exerting an antidepressant effect. 展开更多
关键词 adolescents CYTOKINES EFFICACY Goji berry inflammatory responses INTERLEUKIN-17A Lycium barbarum polysaccharide randomized controlled study subthreshold depression
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Experimental Design of Observational Studies in Real-World Study
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作者 Qu Yi Wang Yuzhuo +3 位作者 Yuan Xiaoliang Wang Chuang Huang Zhe Chen Yuwen 《Asian Journal of Social Pharmacy》 2022年第3期222-228,共7页
Objective To introduce the design of observational trials under real-world study(RWS),and to provide guidance for clinical development of new research trials and reference for real-world researchers.Methods Relevant l... Objective To introduce the design of observational trials under real-world study(RWS),and to provide guidance for clinical development of new research trials and reference for real-world researchers.Methods Relevant literature of RWS and observational experiments at home and abroad were reviewed and analyzed,and then the design of observational studies was summarized under RWS.Results and Conclusion The data and information provided in observational studies not only help to further verify the clinical study results obtained by randomized controlled trial(RCT)in clinical practice,but also objectively reflect the real situation in the process of clinical research and application. 展开更多
关键词 real-world study(RWS) randomized controlled trial(RCT) observational study*Corresponding
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Botulinum toxin type A for treating chronic low back pain:A double blinded randomized control study
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作者 Mantu Jain Shahnawaz Khan +2 位作者 Paulson Varghese Sujit Kumar Tripathy Manaswini Mangaraj 《World Journal of Methodology》 2024年第3期119-125,共7页
BACKGROUND Low back pain(LBP)is a prevalent issue that orthopedic surgeons frequently address in the outpatient setting.LBP can arise from various causes,with stiffness in the paraspinal muscles being a notable contri... BACKGROUND Low back pain(LBP)is a prevalent issue that orthopedic surgeons frequently address in the outpatient setting.LBP can arise from various causes,with stiffness in the paraspinal muscles being a notable contributor.The administration of Botulinum toxin type A(BoNT-A)has been found to alleviate back pain by relaxing these stiff muscles.While BoNT-A is approved for use in numerous conditions,a limited number of randomized clinical trials(RCTs)validate its efficacy specifically for treating LBP.AIM To study the safety and the efficacy of BoNT-A in minimizing pain and improving functional outcomes in patients of chronic LBP(CLBP).METHODS In this RCT,adults aged 18-60 years with mechanical LBP persisting for at least six months were enrolled.Participants were allocated to either the Drug group,receiving 200 Ipsen Units(2 mL)of BoNT-A,or the Control group,which received a 2 mL placebo.Over a 2-month follow-up period,both groups were assessed using the Visual Analog Scale(VAS)for pain intensity and the Oswestry Disability Index(ODI)for disability at the start and conclusion of the study.A decrease in pain by 50%was deemed clinically significant.RESULTS The study followed 40 patients for two months,with 20 in each group.A clinically significant reduction in pain was observed in 36 participants.There was a statistically significant decrease in both VAS and ODI scores in the groups at the end of two months.Nonetheless,when comparing the mean score changes,only the reduction in ODI scores(15 in the placebo group vs 16.5 in the drug group,clinically insignificant)was statistically significant(P=0.012),whereas the change in mean VAS scores was not significant(P=0.45).CONCLUSION The study concludes that BoNT-A does not offer a short-term advantage over placebo in reducing pain or improving LBP scores in CLBP patients. 展开更多
关键词 Botulinum toxin type A Chronic low back pain Randomized control study Double-blinded Pain management Therapeutic efficacy
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黄体生成素/促卵泡生成素比值对快进展型中枢性性早熟的预测价值研究
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作者 袁淑娴 林一凡 +3 位作者 赵艺璇 魏怡 鲁帅 卫海燕 《中国全科医学》 CAS 北大核心 2025年第3期352-357,共6页
背景 中枢性性早熟(CPP)是儿童内分泌常见疾病,近年来呈逐年增加趋势,依据青春期发育进程可分为快进展型中枢性性早熟(RP-CPP)和缓慢进展型中枢性性早熟(SP-CPP)。RP-CPP具有极大危害,其与SPCPP在早期临床鉴别中存在困难,主要依靠随访... 背景 中枢性性早熟(CPP)是儿童内分泌常见疾病,近年来呈逐年增加趋势,依据青春期发育进程可分为快进展型中枢性性早熟(RP-CPP)和缓慢进展型中枢性性早熟(SP-CPP)。RP-CPP具有极大危害,其与SPCPP在早期临床鉴别中存在困难,主要依靠随访中青春期发育进程及骨龄进展情况进行判断,目前缺乏有效的实验室检查指标来预测RP-CPP。目的 探讨促黄体生成素(LH)/促卵泡生成素(FSH)比值对RP-CPP的预测价值。方法回顾性选取2020年1月—2022年5月郑州大学附属儿童医院收治的4~10岁CPP女童(n=380),依据青春期发育进程等指标分为RP-CPP组(n=130)及SP-CPP组(n=250),对两组间的临床特征进行对比分析,进行RP-CPP影响因素的单因素和多因素Logistic回归分析,并绘制LH/FSH比值对RP-CPP预测价值的受试者工作特征(ROC)曲线。结果 RP-CPP组女童的身高、体质量、BMI、胰岛素样生长因子1(IGF-1)、骨龄与实际年龄差值、双侧卵巢体积、LH基础值、雌二醇水平、LH基础值/FSH基础值、LH峰值/FSH峰值均高于SP-CPP组(P<0.05)。多因素Logistic回归分析,结果显示,LH基础值(OR=0.882,95%CI=0.686~0.986,P=0.035)及LH峰值/FSH峰值(OR=0.492,95%CI=0.336~0.723,P<0.001)是CPP患者进展为RP-CPP的影响因素。LH基础值/FSH基础值、LH峰值/FSH峰值均与身高、IGF-1、LH基础值、雌二醇水平、LH峰值、卵巢容积及骨龄呈正相关(P<0.05)。ROC曲线显示LH基础值/FSH基础值、LH峰值/FSH峰值较其他指标对RP-CPP的预测价值更高,LH基础值/FSH基础值为0.63时,约登指数最大为0.258[灵敏度为43.1%,特异度为82.7%,ROC曲线下面积(AUC)=0.644],LH峰值/FSH峰值为1.39时,约登指数最大为0.276(灵敏度为74.6%,特异度53.0%,AUC=0.655),二者联合的预测模型优于单一指标预测模型(AUC=0.668)。对未进行临床干预患儿随访6个月后的基础促性腺激素水平进行分析,随访6个月后RP-CPP组的身高增长、ΔLH、ΔFSH、骨龄增长及卵巢容积增长均多于SP-CPP组(P<0.05)。结论 LH基础值/FSH基础值及LH峰值/FSH峰值是RP-CPP的早期预测指标,当LH/FSH基础值≥0.63或LH峰值/FSH峰值≥1.39时,需考虑RP-CPP的可能性,并且二者联合的预测价值优于单一指标,可作为临床应用促性腺激素释放激素类似物治疗的辅助参考指标。 展开更多
关键词 中枢性性早熟 促卵泡激素 黄体生成素 青春期发育 女童 病例对照研究
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急性后循环缺血性脑卒中患者睡眠状态变化与预后影响因素的研究
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作者 张萍淑 薛晶 +4 位作者 邢爱君 王连辉 马倩 符永山 元小冬 《中国全科医学》 CAS 北大核心 2025年第5期548-553,共6页
背景脑卒中患者通常伴有睡眠状态紊乱失衡,这在临床治疗中极易被忽视,且目前针对睡眠状态是否对该类疾病预后产生影响的研究较少。目的探究急性后循环缺血性脑卒中患者睡眠状态变化与预后影响的因素。方法选取2019年12月—2023年12月在... 背景脑卒中患者通常伴有睡眠状态紊乱失衡,这在临床治疗中极易被忽视,且目前针对睡眠状态是否对该类疾病预后产生影响的研究较少。目的探究急性后循环缺血性脑卒中患者睡眠状态变化与预后影响的因素。方法选取2019年12月—2023年12月在华北理工大学附属开滦总医院诊治的急性后循环缺血性脑卒中患者60例为病例组,根据患者出院时改良Rankin(mRS)评分,将病例组分为预后良好亚组45例,预后不良亚组15例。选取同时期无脑血管狭窄且无急性缺血性脑卒中患者52例作为对照组。收集患者一般及临床资料,比较病例组与对照组患者昼夜睡眠-觉醒节律、日间睡眠-觉醒节律、夜间睡眠-觉醒节律指标以及预后良好亚组与预后不良亚组梗死脑区分布的差异性。采用多因素Logistic回归分析探讨急性后循环缺血性脑卒中患者预后不良的影响因素。结果病例组睡眠呼吸暂停低通气指数(AHI)高于对照组(P<0.05)。病例组睡眠周期颠倒、日间睡眠增多、夜间入睡困难所占比例高于对照组(P<0.05)。病例组日间总睡眠时间、入睡后清醒时间、浅睡眠期、深睡眠期、非快速眼动(NREM)睡眠期、快速眼动(REM)睡眠期、REM睡眠期占比、深睡眠期占比高于对照组,NREM睡眠期占比、浅睡眠期占比低于对照组(P<0.05)。病例组夜间总睡眠时间、浅睡眠期、NREM睡眠期高于对照组(P<0.05)。预后不良亚组桥脑梗死占比高于预后良好亚组(P<0.05)。多因素Logistic回归分析结果显示,日间深睡眠期(OR=1.203,95%CI=1.032~1.401)、桥脑梗死(OR=16.497,95%CI=1.142~238.391)是急性后循环缺血性脑卒中预后不良的影响因素(P<0.05)。结论急性后循环缺血性脑卒中患者AHI增高,睡眠状态特征为睡眠周期颠倒、日间睡眠增多、夜间入睡困难,且日间深睡眠期、桥脑梗死是患者预后不良的影响因素。 展开更多
关键词 卒中 脑梗死 后循环 睡眠状态 预后 病例对照研究 影响因素分析
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家庭认知环境对儿童早期语言发育的影响:一项上海市的回顾性病例对照研究
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作者 郭志超 崔丹 +4 位作者 包嘉珺 施渭青 韦康 杨兴堂 俞文雅 《中国全科医学》 CAS 北大核心 2025年第1期53-58,共6页
背景儿童早期语言发育迟缓发生率高、早期识别率低,对儿童其他维度的早期发展有显著负面影响。家庭认知环境是影响儿童早期语言发育的关键因素。目的本研究旨在探索家庭认知环境对儿童早期语言发育的影响,从家庭认知环境的社区干预角度... 背景儿童早期语言发育迟缓发生率高、早期识别率低,对儿童其他维度的早期发展有显著负面影响。家庭认知环境是影响儿童早期语言发育的关键因素。目的本研究旨在探索家庭认知环境对儿童早期语言发育的影响,从家庭认知环境的社区干预角度,为儿童早期的语言发育促进提供理论证据。方法采用回顾性病例对照研究,对2018—2020年在上海市某社区卫生服务中心儿童保健门诊体检的4307名儿童在1、2、3周岁时采用上海市小儿发育筛查量表Ⅱ(DenveRⅡ)进行发育筛查,将筛查出的语言发育迟缓的172名儿童作为观察组,以年龄作为配对因素,按照1∶3的比例纳入516名语言发育正常的儿童作为对照组。收集两组儿童出生基本特征、父母人口学特征、母亲孕期和分娩特征以及家庭认知环境特征信息。采用Logistic回归分析探讨儿童早期语言发育迟缓的影响因素。结果早期语言发育迟缓的儿童共172名,发生率为3.99%,其中,1岁儿童57名(33.14%),2岁儿童92名(53.49%),3岁儿童23名(13.37%)。病例组儿童男性、早产、母亲文化程度为高中以下比例高于对照组(P<0.05)。病例组儿童的总体家庭认知环境及情感温暖、社会适应、语言环境和忽视环境弱于对照组(P<0.05)。儿童早产、母亲文化程度低(高中以下)、家庭认知环境不良是儿童早期语言发育迟缓的危险因素(P<0.05)。结论在2岁前进行语言发育干预是有效降低儿童语言发育迟缓率的关键。社区儿童保健医生指导优化家庭养育环境、协助建立良好亲子沟通和交流互动,是促进儿童早期语言发育的有效策略,尤其要关注出生胎龄小和母亲文化程度低的家庭,为其提供更有针对性的亲子活动和亲子沟通方面的干预和指导。 展开更多
关键词 语言发展障碍 家庭环境 认知环境 儿童 儿童语言 儿童早期发展 病例对照研究
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Associations of lifestyle and diet with the risk of nasopharyngeal carcinoma in Singapore:a case–control study 被引量:13
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作者 Sook Kwin Yong Tam Cam Ha +3 位作者 Ming Chert Richard Yeo Valerie Gaborieau James D.McKay Joseph Wee 《Chinese Journal of Cancer》 SCIE CAS CSCD 2017年第2期63-70,共8页
Background: Nasopharyngeal carcinoma(NPC) is a commonly diagnosed cancer in Southeast Asia. Many studies have examined the risk factors for NPC, yet the roles of some risk factors remain inconclusive. The purpose of t... Background: Nasopharyngeal carcinoma(NPC) is a commonly diagnosed cancer in Southeast Asia. Many studies have examined the risk factors for NPC, yet the roles of some risk factors remain inconclusive. The purpose of this study was to examine associations between modifiable lifestyle factors and the risk of NPC in the Singaporean population.Methods: We conducted a case–control study in Singapore with 300 patients and 310 controls who were recruited between 2008 and 2012. Each control was selected and individually matched to each patient based on sex, ethnicity, and age(±5 years). A total of 290 pairs of cases and controls were matched successfully. We examined lifestyle factors such as tobacco smoking, alcohol drinking, various salted and preserved food consumption, and weaning practices.Results: After adjusting for covariates, multivariate analysis showed that those participants who were current smokers and had ever smoked tobacco had a higher risk of NPC than participants who had never smoked, with odds ratios(ORs) of 4.50(95% confidence interval [CI] 2.58–7.86; P < 0.001) and 2.52(95% CI 1.54–4.12; P < 0.001), respectively. Those who consumed salted vegetables at least once a week also showed a significantly increased risk of NPC than those who never or rarely consumed salted vegetables, with an OR of 4.18(95% CI 1.69–10.38; P = 0.002).Conclusion: Smoking(currently and ever-smoked) and consuming salted vegetables once a week or more were lifestyle risk factors for NPC, and changes of these factors for the better may reduce the risk of NPC. 展开更多
关键词 Nasopharyngeal carcinoma DIET SMOKING Alcohol drinking Case–control study Preserved food
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Functional and psychosocial effects of pulmonary Daoyin on patients with COPD in China:study protocol of a multicenter randomized controlled trial 被引量:15
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作者 Xue-qing Yu Jian-sheng Li +5 位作者 Su-yun Li Yang Xie Ming-hang Wang Hai-long Zhang Hai-feng Wang Zhi-wan Wang 《Journal of Integrative Medicine》 SCIE CAS CSCD 2013年第2期140-146,共7页
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major public health problem worldwide. Pulmonary rehabilitation (PR) is an established intervention for the management of patients with COPD. Exercise... BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major public health problem worldwide. Pulmonary rehabilitation (PR) is an established intervention for the management of patients with COPD. Exercise training is an important part of PR, and its effectiveness in patients with COPD is well established. However, alternative methods of PR training such as Daoyin have not been appropriately studied. Hence, alternative forms of exercise training that require less exercise equipment and no specific training place should be evaluated. This paper describes the study protocol of a clinical trial that aims to determine if pulmonary Daoyin training will improve the exercise capacity and psychosocial function of patients with COPD in China. METHODS AND DESIGN: A multicenter, randomized, controlled trial will be conducted. A total of 464 patients meeting the inclusion criteria will be enrolled into this study with 232 patients in each of the trial group and the control group. Based on patient education, patients in the trial group will receive pulmonary Daoyin and continue with their usual therapy for three months. In the control group, patients will continue with their usual therapy. The primary outcome measures are exercise capacity assessed by the six-minute walking distance test and lung function. Secondary outcomes include dyspnea and quality of life. Measurements will be taken at baseline (month 0) and after the study period (month 3). DISCUSSION: It is hypothesized that pulmonary Daoyin will have beneficial effects in improving exercise capacity and psychosocial function of patients with stable COPD, and will provide an alternative form of exercise training that is accessible for the large number of people with COPD. TRIAL REGISTRATION: This trial has been registered in ClinicalTrials.gov. The identifier is NCT01482000. 展开更多
关键词 chronic obstructive pulmonary disease DAOYIN randomized controlled trial study protocol
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Human umbilical cord mesenchymal stem cells to treat spinal cord injury in the early chronic phase: study protocol for a prospective, multicenter, randomized, placebo-controlled, single-blinded clinical trial 被引量:9
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作者 Yang Yang Mao Pang +5 位作者 Yu-Yong Chen Liang-Ming Zhang Hao Liu Jun Tan Bin Liu Li-Min Rong 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第8期1532-1538,共7页
Human umbilical cord mesenchymal stem cells(hUC-MSCs)support revascularization,inhibition of inflammation,regulation of apoptosis,and promotion of the release of beneficial factors.Thus,they are regarded as a promisin... Human umbilical cord mesenchymal stem cells(hUC-MSCs)support revascularization,inhibition of inflammation,regulation of apoptosis,and promotion of the release of beneficial factors.Thus,they are regarded as a promising candidate for the treatment of intractable spinal cord injury(SCI).Clinical studies on patients with early chronic SCI(from 2 months to 1 year post-injury),which is clinically common,are rare;therefore,we will conduct a prospective,multicenter,randomized,placebo-controlled,single-blinded clinical trial at the Third Affiliated Hospital of Sun Yat-sen University,West China Hospital of Sichuan University,and Shanghai East Hospital,Tongji University School of Medicine,China.The trial plans to recruit 66 early chronic SCI patients.Eligible patients will undergo randomization at a 2:1 ratio to two arms:the observation group and the control group.Subjects in the observation group will receive four intrathecal transplantations of stem cells,with a dosage of 1×106/kg,at one calendar month intervals.Subjects in the control group will receive intrathecal administrations of 10 mL sterile normal saline in place of the stem cell transplantations.Clinical safety will be assessed by the analysis of adverse events and laboratory tests.The American Spinal Injury Association(ASIA)total score will be the primary efficacy endpoint,and the secondary efficacy outcomes will be the following:ASIA impairment scale,International Association of Neural Restoration-Spinal Cord Injury Functional Rating Scale,muscle tension,electromyogram,cortical motor and cortical sensory evoked potentials,residual urine volume,magnetic resonance imaging–diffusion tensor imaging,T cell subtypes in serum,neurotrophic factors and inflammatory factors in both serum and cerebrospinal fluid.All evaluations will be performed at 1,3,6,and 12 months following the final intrathecal administration.During the entire study procedure,all adverse events will be reported as soon as they are noted.This trial is designed to evaluate the clinical safety and efficacy of subarachnoid transplantation of hUC-MSCs to treat early chronic SCI.Moreover,it will establish whether cytotherapy can ameliorate local hostile microenvironments,promote tracking fiber regeneration,and strengthen spinal conduction ability,thus improving overall motor,sensory,and micturition/defecation function in patients with early chronic SCI.This study was approved by the Stem Cell Research Ethics Committee of the Third Affiliated Hospital of Sun Yat-sen University,China(approval No.[2018]-02)on March 30,2018,and was registered with ClinicalTrials.gov(registration No.NCT03521323)on April 12,2018.The revised trial protocol(protocol version 4.0)was approved by the Stem Cell Research Ethics Committee of the Third Affiliated Hospital of Sun Yat-sen University,China(approval No.[2019]-10)on February 25,2019,and released on ClinicalTrials.gov on April 29,2019. 展开更多
关键词 clinical study early chronic phase efficacy human umbilical cord mesenchymal stem cell multicenter trial prospective study randomized controlled trial safety spinal cord injury study protocol
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Experimental Study on Characteristics of NiMnGa Magnetically Controlled Shape Memory Alloy 被引量:8
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作者 Fengxiang WANG Wenjun LI Qingxin ZHANG Chenxi LI Xinjie WU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第1期55-58,共4页
The static and dynamic magnetic controlling characteristics of NiMnGa magnetically controlled shape memory alloy (MSMA) were experimentally studied. The results show that the characteristics of induced strain with r... The static and dynamic magnetic controlling characteristics of NiMnGa magnetically controlled shape memory alloy (MSMA) were experimentally studied. The results show that the characteristics of induced strain with respect to the magnetic field are nonlinear with saturation nature, and dependent on the temperature as well as the load applied to the MSMA. The magnetic shape memory effect can be observed only in complete martensite phase at room temperature. The magnetic permeability of MSMA is not constant and reduces with the increment of magnetic field. The relative saturation magnetic permeability of MSMA is about 1.5. 展开更多
关键词 NIMNGA Magnetically controlled shape memory alloy CHARACTERISTICS Experimental study
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Iterative Learning Control Algorithm with a Fixed Step 被引量:4
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作者 WANG Yan NIU Jianjun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期669-675,共7页
Iterative Learning Control (ILC) captures interests of many scholars because of its capability of high precision control implement without identifying plant mathematical models, and it is widely applied in control e... Iterative Learning Control (ILC) captures interests of many scholars because of its capability of high precision control implement without identifying plant mathematical models, and it is widely applied in control engineering. Presently, most ILC algorithms still follow the original ideas of ARIMOTO, in which the iterative-learning-rate is composed by the control error with its derivative and integral values. This kind of algorithms will result in inevitable problems such as huge computation, big storage capacity for algorithm data, and also weak robust. In order to resolve these problems, an improved iterative learning control algorithm with fixed step is proposed here which breaks the primary thought of ARIMOTO. In this algorithm, the control step is set only according to the value of the control error, which could enormously reduce the computation and storage size demanded, also improve the robust of the algorithm by not using the differential coefficient of the iterative learning error. In this paper, the convergence conditions of this proposed fixed step iterative learning algorithm is theoretically analyzed and testified. Then the algorithm is tested through simulation researches on a time-variant object with randomly set disturbance through calculation of step threshold value, algorithm robustness testing,and evaluation of the relation between convergence speed and step size. Finally the algorithm is validated on a valve-serving-cylinder system of a joint robot with time-variant parameters. Experiment results demonstrate the stability of the algorithm and also the relationship between step value and convergence rate. Both simulation and experiment testify the feasibility and validity of the new algorithm proposed here. And it is worth to noticing that this algorithm is simple but with strong robust after improvements, which provides new ideas to the research of iterative learning control algorithms. 展开更多
关键词 iterative learning control fixed step time variant system simulating study robot control
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Control performance comparison between tuned liquid damper and tuned liquid column damper using real-time hybrid simulation 被引量:4
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作者 Zhu Fei Wang Jinting +1 位作者 Jin Feng Lu Liqiao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第3期695-701,共7页
Tuned liquid damper (TLD) and tuned liquid column damper (TLCD) are two types of passive control devices that are widely used in structural control. In this study, a real-time hybrid simulation (RTHS) technique is emp... Tuned liquid damper (TLD) and tuned liquid column damper (TLCD) are two types of passive control devices that are widely used in structural control. In this study, a real-time hybrid simulation (RTHS) technique is employed to investigate the diff erence in control performance between TLD and TLCD. A series of RTHSs is presented with the premise of the same liquid length, mass ratio, and structural parameters. Herein, TLD and TLCD are physically experimented, and controlled structures are numerically simulated. Then, parametric studies are performed to further evaluate the diff erent performance between TLD and TLCD. Experimental results demonstrate that TLD is more eff ective than TLCD under diff erent amplitude excitations. 展开更多
关键词 tuned LIQUID DAMPER tuned LIQUID COLUMN DAMPER real-time hybrid simulation control effi ciency STRUCTURAL control PARAMETRIC study
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Development of Temperature-Humidity Independent Control Air-Conditioning Unit for Residential Buildings 被引量:3
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作者 HAN Xing1,ZHANG Xu1,LIU Jin-tao2,GAO Si-yun2,KANG Yue2(1.Institute of HVAC & Gas,College of Mechanical Engineering,Tongji University,Shanghai 200092,China 2.Hisense R&D Center,Qingdao,266000,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期83-87,共5页
Cooling panels are increasingly used in domestic residential buildings.To provide medium temperature cold water for the cooling panel,and dehumidify the indoor air simultaneously,a new kind of temperature-humidity ind... Cooling panels are increasingly used in domestic residential buildings.To provide medium temperature cold water for the cooling panel,and dehumidify the indoor air simultaneously,a new kind of temperature-humidity independent control air-conditioning unit was developed for single residential house by utilizing multi-variable technology.First,the supply air temperature was studied to determine the proper supply air flow rate for the humidity control.Then,the energy consumption of different temperature-humidity independent control systems was studied.The analysis indicates that unity evaporating temperature can be used to handle the moisture load and sensible heat load in two evaporators.So the unit scheme was put forward.Two evaporators were used to produce medium temperature water and dry air separately,and electric expansion valves were used to control the refrigerant distribution between the two evaporators.Then,experimental work was carried out to investigate the influence of compressor frequency,refrigerant distribution on the dehumidification capacity,energy efficiency and refrigeration capacity.In the end,the paper concludes that both compressor frequency and refrigerant distribution can control the dehumidification capacity,but the former influences the EER more than the latter,while the latter influences the refrigeration capacity more than the former.We can find a proper running point at certain sensible and latent cooling load by adjusting both compressor frequency and electric expansion valve.The energy consumption of this kind of unit was estimated and compared with present room air conditioners,which shows that it can save about 41% cooling energy consumption. 展开更多
关键词 temperature-humidity INDEPENDENT control RESIDENTIAL BUILDINGS COLD DEHUMIDIFICATION experimental study
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