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Inflammatory Bowel Disease and Dementia:Evidence Triangulation from a Meta-Analysis of Observational Studies and Mendelian Randomization Study
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作者 Di Liu Meiling Cao +9 位作者 Shanshan Wu Bingli Li Yiwen Jiang Tengfei Lin Fuxiao Li Weijie Cao Jinqiu Yuan Feng Sha Zhirong Yang Jinling Tang 《Biomedical and Environmental Sciences》 2025年第1期56-66,共11页
Objective Observational studies have found associations between inflammatory bowel disease(IBD)and the risk of dementia,including Alzheimer’s dementia(AD)and vascular dementia(VD);however,these findings are inconsist... Objective Observational studies have found associations between inflammatory bowel disease(IBD)and the risk of dementia,including Alzheimer’s dementia(AD)and vascular dementia(VD);however,these findings are inconsistent.It remains unclear whether these associations are causal.Methods We conducted a meta-analysis by systematically searching for observational studies on the association between IBD and dementia.Mendelian randomization(MR)analysis based on summary genome-wide association studies(GWASs)was performed.Genetic correlation and Bayesian colocalization analyses were used to provide robust genetic evidence.Results Ten observational studies involving 80,565,688 participants were included in this metaanalysis.IBD was significantly associated with dementia(risk ratio[RR]=1.36,95%CI=1.04-1.78;I2=84.8%)and VD(RR=2.60,95%CI=1.18-5.70;only one study),but not with AD(RR=2.00,95%CI=0.96-4.13;I^(2)=99.8%).MR analyses did not supported significant causal associations of IBD with dementia(dementia:odds ratio[OR]=1.01,95%CI=0.98-1.03;AD:OR=0.98,95%CI=0.95-1.01;VD:OR=1.02,95%CI=0.97-1.07).In addition,genetic correlation and co-localization analyses did not reveal any genetic associations between IBD and dementia.Conclusion Our study did not provide genetic evidence for a causal association between IBD and dementia risk.The increased risk of dementia observed in observational studies may be attributed to unobserved confounding factors or detection bias. 展开更多
关键词 DEMENTIA Inflammatory bowel disease META-ANALYSIS observational studies Mendelian randomization Genetic evidence Evidence triangulation
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Hepatitis B or C viral infection and risk of pancreatic cancer: A meta-analysis of observational studies 被引量:8
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作者 Jian-Hua Xu Jin-Jian Fu +3 位作者 Xiao-Li Wang Jia-Yong Zhu Xiao-Hua Ye Si-Dong Chen 《World Journal of Gastroenterology》 SCIE CAS 2013年第26期4234-4241,共8页
AIM: To investigate if there is an association between hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and the risk of pancreatic cancer. METHODS: All relevant studies published before 11 October, 2012 we... AIM: To investigate if there is an association between hepatitis B virus (HBV) or hepatitis C virus (HCV) infection and the risk of pancreatic cancer. METHODS: All relevant studies published before 11 October, 2012 were identified by a systematic search of MEDLINE, EMBASE, BIOSIS Previews and the Cochrane Library databases and with cross-referencing. The observational studies that reported RR or OR estimates with 95%CIs for the association between HBV or HCV and pancreatic cancer were included. A random-effects model was used to summarize meta-analytic estimates. The Newcastle-Ottawa quality assessment scale was applied to assess the quality of the methodology in the included studies. RESULTS: A total of 8 eligible studies were selected for meta-analysis. Overall, chronic hepatitis B and inactive hepatitis B surface antigen (HBsAg) carrier state (HBsAg positive) had a significantly increased risk of pancreatic cancer with OR of 1.20 (95%CI: 1.01-1.39), especially in the Chinese population (OR = 1.30, 95%CI: 1.05-1.56). Past exposure to HBV (possible occult HBV infection) had an increased OR of pancreatic cancer risk (OR = 1.24, 95%CI: 1.05-1.42), especially among those patients without natural immunity [anti hepatitis B core (HBc) positive/hepatitis B surface antibody (anti HBs) negative], with OR of 1.67 (95%CI: 1.13-2.22). However, past exposure to HBV with natural immunity (anti-HBc positive/anti-HBs positive) had no association with pancreatic cancer development, with OR 0.98 (95%CI: 0.80-1.16), nor did the HBV active replication (hepatitis B e antigen positive status), with OR 0.98 (95%CI: 0.27-1.68). The risk of pancreatic cancer among anti-HBs positive patients was significantly lower than among anti-HBs negative patients (OR = 0.54, 95%CI: 0.46-0.62). Past exposure to HCV also resulted in an increased risk of pancreatic cancer (OR = 1.26, 95%CI: 1.03-1.50). Significant between-study heterogeneity was observed. Evidence of publication bias for HBV/HCV infection-pancreatic cancer association was not found. CONCLUSION: Chronic HBV and HCV infection increases pancreatic cancer risk. Our findings underscore the need for more studies to confirm this potential relationship. 展开更多
关键词 HEPATITIS B HEPATITIS C PANCREATIC cancer observational studies META-ANALYSIS
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Partial Least Squares Method for Treatment Effect in Observational Studies with Censored Outcomes 被引量:2
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作者 CAO Yongxiu YU Jichang 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2018年第6期487-492,共6页
To estimate the true treatment effect on a censored outcome in observational studies, potential confounding effect and complex heterogeneity in the treatment assignment have to be properly adjusted. In this article, w... To estimate the true treatment effect on a censored outcome in observational studies, potential confounding effect and complex heterogeneity in the treatment assignment have to be properly adjusted. In this article, we demonstrate that the partial least squares method could be a valuable tool in this regard. It is showed that the partial least squares method not only can adequately account for the heterogeneity in treatment assignment, but also be robust to treatment assignment model misspecifications. Numerical results show that the partial least squares estimator is more efficient and robust. A real data set is analyzed to illustrate the proposed method. 展开更多
关键词 HETEROGENEITY observational study partial leastsquares propensity score
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Red meat intake and the risk of endometrial cancer:Metaanalysis of observational studies 被引量:2
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作者 Woong Ju Na Na Keum +4 位作者 Dong Hoon Lee Yun Hwan Kim Seung Cheol Kim Eric L Ding Eunyoung Cho 《World Journal of Meta-Analysis》 2015年第2期125-132,共8页
AIM:To evaluate whether red meat intake is related to the risk of endometrial cancer(EC) using meta-analysis.METHODS:We searched Pub Med,EMBASE,and the Cochrane Library up to June 2013,using common keywords related to... AIM:To evaluate whether red meat intake is related to the risk of endometrial cancer(EC) using meta-analysis.METHODS:We searched Pub Med,EMBASE,and the Cochrane Library up to June 2013,using common keywords related to red meat and EC.Case-control studies and cohort studies comparing the risk of endometrial cancer among categories by the amount of intake were included.Eleven case-control studies and five cohort studies met our criteria.We performed a conventional and a dose-response meta-analysis of case-control studies using the Der Simonian-Laird method for random-effects.For cohort studies we performed a conventional meta-analysis.Publication bias was evaluated using Egger's test.RESULTS:In the meta-analysis of 11 case-control studies including 5419 cases and 12654 controls,higher red meat consumption was associated with an increased risk of EC [summary relative risk(SRR) = 1.43,95%CI:1.15-1.79;I2 = 73.3% comparing extreme intake categories).In a dose-response analysis,for red meat intake of 100 g/d,SRR was 1.84(95%CI:1.64-2.05).In contrast,in the meta-analysis of five prospective studies including a total of 2549 cases among 247746 participants,no significant association between red meat intake and EC risk(SRR = 0.97,95%CI:0.85-1.11;I2 = 4.9% comparing extreme intake categories) was observed.CONCLUSION:Our meta-analysis found a significantlinear association between red meat intake and EC risk based on case-control studies but this was not confirmed in prospective studies. 展开更多
关键词 Red meat Endometrial cancer Doseresponse META-ANALYSIS observational studies
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Gut microbiota changes associated with frailty in older adults:A systematic review of observational studies 被引量:1
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作者 Na-Na Wen Li-Wei Sun +1 位作者 Qian Geng Guo-Hua Zheng 《World Journal of Clinical Cases》 SCIE 2024年第35期6815-6825,共11页
BACKGROUND Frailty is a complex aging-related syndrome characterized by a cumulative loss of physiological reserve and increased vulnerability to adverse clinical outcomes,including falls,disability,incapacity and dea... BACKGROUND Frailty is a complex aging-related syndrome characterized by a cumulative loss of physiological reserve and increased vulnerability to adverse clinical outcomes,including falls,disability,incapacity and death.While an increasing number of studies suggest that the gut microbiota may play a key role in the pathophy-siology of frailty,direct evaluation of the association between gut microbiome alterations and frailty in older adults remains limited.AIM Seven electronic databases(China National Knowledge Infrastructure,VIP,SinoMed,Wanfang,PubMed,Web of Science and EMBASE)were searched for articles published before October 31,2023 to identify observational studies that compared the microbiomes of older adults with and without frailty.The diversity and composition of the gut microbiota were the main outcomes used to analyze the associations of changes in the gut microbiota with frailty in older adults.The quality of the included studies was assessed via the Newcastle-Ottawa Scale and the Agency for Healthcare Research and Quality.RESULTS Eleven observational studies with 912 older adults were included in this review.Consistent results revealed a significant difference in the gut microbiota composition between frail and non-frail older adults,with a significant decrease inαdiversity and a significant increase inβdiversity in frail older adults.The pooled results revealed that at the phylum level,four microbiota(Actinobacteria,Proteo-bacteria,Verrucomicrobia and Synergistetes)were significantly enriched,and two microbiota(Firmicutes and Fusobacteria)were significantly depleted in frail older adults.At the family level,the results consistently revealed that the abundances of 6 families,most of which belong to the Actinobacteria or Proteo-bacteria phylum,were greater in frail than in non-frail older adults.At the genus or species level,consistent results from more than two studies revealed that the abundances of the genera Prevotella,Faecalibacterium,and Roseburia were significantly lower in frail older adults;individual studies revealed that the abundances of some genera or species(e.g.,Megamonas,Blautia,and Megasphaera)were significantly lower,whereas those of other genera or species(e.g.,Bifidobacterium,Oscillospira,Ruminococcus and Pyramidobacter)were significantly greater in frail older adults.CONCLUSION This systematic review suggests that changes in the gut microbiota are associated with frailty in older adults,which is commonly reflected by a reduction in beneficial species and an increase in pathogenic species.However,further studies are needed to confirm these findings. 展开更多
关键词 FRAILTY Gut microbiota observational study Older adults Systematic review
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Determination of Causal Effect in Observational Studies: Analysis of Correlated Data with Binary End-Points 被引量:1
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作者 Maupi Eric Letsoalo Maseka Lesaoana 《Journal of Mathematics and System Science》 2012年第2期119-125,共7页
Identifying the causal impact of' some intervention challenging when one is faced with correlated binary end-points in observational studies is a challenging task, and it is even more The statistical literature on an... Identifying the causal impact of' some intervention challenging when one is faced with correlated binary end-points in observational studies is a challenging task, and it is even more The statistical literature on analyzing such data is well documented. Dependence between observations from the same study subject in correlated data renders invalid the usual chi-square tests of independence and inflates the variance ofparameter estimates. Disaggregated approaches such as hierarchical linear models which are able to adjust for individual level covariate:s are favoured in the analysis of such data, thereby gaining power over aggregated and individual-level analyses. In this article the authors, therefore, address the issue of analyzing correlated data with dichotomous end-points by using hierarchical logistic regression, a generalization of the standard logistic regression model for independent outcomes. 展开更多
关键词 Correlated data observational studies counterfactual problem hierarchical models group randomization treatment effect.
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Factors that Motivate Participation in Observational Genetic Cancer Research Studies
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作者 Deborah Goodman Catherine O. Johnson +2 位作者 Deborah Bowen Lari Wenzel Karen Edwards 《Open Journal of Epidemiology》 2019年第2期156-172,共17页
Demographics, access to new treatment, altruistic motivations and continuity of care have been shown to influence motivation to participate in clinical trials. Less is known however, about factors that motivate resear... Demographics, access to new treatment, altruistic motivations and continuity of care have been shown to influence motivation to participate in clinical trials. Less is known however, about factors that motivate research participants to agree to take part in observational studies and provide a biologic specimen. This study evaluates and quantitates factors that motivate participation in observational studies and provide a biospecimen among cancer patients, their family members, and controls. An online survey was completed by 450 participants from a cancer genetics registry, including cancer patients, their relatives, and controls. Overall, the benefit to society and the research institution reputation were the most important motivators for participation. Cancer cases were significantly more likely to endorse personal meaningfulness as a factor for participation compared to those without cancer and women were 50% more likely than men to believe that a family benefit is an important determinant of research participation. Researcher and institutional trustworthiness as well as security of stored data were most important when deciding whether to provide a biological sample, with differences seen by gender and history of cancer. This study demonstrated which factors are most important to participants when considering participation in an observational study and donating a biospecimen. Motivational factors significantly differed by gender as well as history and stage of cancer. The application of these study results may improve participation rates in cohort studies. 展开更多
关键词 PARTICIPATION Research MOTIVATION observational studies
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A Systematic Review of Observational Studies, Demonstrating Smoking among School Going Adolescents
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作者 Shafquat Rozi Gillian Lancaster +3 位作者 Sadia Mahmud Zahid Ahmad Butt Talat Roome Nida Zahid 《Open Journal of Epidemiology》 2019年第2期173-189,共17页
Objective: To characterize the methods of design and analysis currently adopted in survey research of school-based observational studies for smoking, and to identify the common pitfalls made by researchers. Methods: T... Objective: To characterize the methods of design and analysis currently adopted in survey research of school-based observational studies for smoking, and to identify the common pitfalls made by researchers. Methods: The systematic review was conducted in 2009 and consisted of observational studies in school settings published between January 2005 and January 2009. Smoking status was the main outcome of interest. Following Cochrane style, five steps were followed: setting selection criteria for studies and conducting a literature search;review of abstracts;review of complete articles;data extraction and quality assessment of included studies;and, finally, synthesis of studies. Results: Of the 292 abstracts retrieved, 45 (15.4%) articles were selected for the final review. Inconsistencies were found in the definition of smoking behaviour which impeded generalisability. Individual-level factors had importance, but environmental level factors were also important in studying the aetiology of smoking. Results showed that studies inappropriately reported sample size estimation and important confounding factors. Hierarchical linear modelling, random effects modelling and structural equation modelling were employed in comparatively few studies. Conclusions: There were concerns regarding data analysis of complex surveys. Fifty five percent of reviewed studies ignored environmental effects which may have produced unreliable inferences. Multi-level analysis assisted in understanding school-level effects. 展开更多
关键词 ADOLESCENT SMOKING observational studies SCHOOL-BASED Survey
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Treatment of active ulcerative colitis with Yinmei Kuijie decoction combined with 5-aminosalicylic acid:A non-randomized multicenter prospective observational protocol based on real-world conditions
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作者 Xinyu Zhang Yuan Li +5 位作者 Ping Li Yunze Liu Junmei Zhang Jingwei Wu Qi Wang Xia Ding 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第4期423-427,共5页
Objective:To determine the efficacy and safety of the Yinmei Kuijie decoction combined with 5-ami-nosalicylic acid(5-ASA)in treating mildly to moderately active ulcerative colitis(UC)under real-world conditions.Method... Objective:To determine the efficacy and safety of the Yinmei Kuijie decoction combined with 5-ami-nosalicylic acid(5-ASA)in treating mildly to moderately active ulcerative colitis(UC)under real-world conditions.Methods:This multicenter,prospective,non-randomized,observational study will be conducted in real-world settings.A total of 204 eligible patients will be consecutively enrolled in the study.Patients in the combination treatment group will receive Yinmei Kuijie decoction in combination with 5-ASA,whereas those in the control group will be treated with 5-ASA alone.The primary endpoint will be a clinical response at week 12,defined as a≥3 point and≥30%reduction from baseline in the Mayo total score with≥1 reduction in rectal bleeding or rectal bleeding score=0 or 1.Secondary efficacy endpoints at week 12 will include health-related quality of life,mucosal healing,and inflammation indicators.Conclusion:The results of this study may provide evidence of the efficacy and safety of Yinmei Kuijie decoction combined with 5-ASA in treating patients with mildly to moderately active UC under real-world principles.The results will provide a basis for further confirmatory studies on the efficacy of Yinmei Kuijie decoction. 展开更多
关键词 Chinese medicine 5-aminosalicylic acid Ulcerative colitis Real-world study Study protocol observational study
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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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Proactive personality and health literacy among patients with permanent colostomy:an observational study
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作者 Wen Li Hui Zheng +3 位作者 Hai-Bo Wang Ye Jiang Zhong-Zhen Yang Soh Kim Lam 《Frontiers of Nursing》 2025年第1期91-98,共8页
Objective:To investigate the distribution of health literacy(HL)levels and the association of HL with proactive personality in patients with permanent colostomy.Methods:A cross-sectional study was conducted to measure... Objective:To investigate the distribution of health literacy(HL)levels and the association of HL with proactive personality in patients with permanent colostomy.Methods:A cross-sectional study was conducted to measure proactive personality and HL using validated scales.A total of 172 patients with permanent colostomy were selected from January 2021 to May 2022 in Yantai City,China.Descriptive statistics,t-test,ANOVA,Pearson correlation analysis,and multiple linear regression analysis techniques were used.Results:The results obtained from the study showed that the HL status of the participants was moderate.The correlation between participants’total HL scores and proactive personality scores was 0.417(P-value<0.001).In addition,HL showed statistically significant differences according to education level,place of residence,profession,and average monthly household income.Conclusions:This study showed that patients with higher proactive personality scores had higher HL.The key stakeholders require several positive strategies to improve the HL of patients with permanent colostomy by cultivating their proactive personalities,and these important policies will help to improve patient health and quality of life. 展开更多
关键词 health literacy observational study permanent colostomy proactive personality surgical nursing
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Clinical observation and experimntal studies of aplastic anemia with human umbilical cord blood transfusion
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《中国输血杂志》 CAS CSCD 2001年第S1期416-,共1页
关键词 Clinical observation and experimntal studies of aplastic anemia with human umbilical cord blood transfusion
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Experimental Studies of Icing Resistanceand Observation of Icing Sleet in Heavy Icing Areaat Huangmaogeng Icing Observation Station
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作者 LiuYu XiongHaixing ChangZhineng 《Electricity》 1999年第4期35-37,共3页
关键词 Experimental studies of Icing Resistanceand observation of Icing Sleet in Heavy Icing Areaat Huangmaogeng Icing observation Station
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Observational Facts Regarding the Joint Activities of the Southwest Vortex and Plateau Vortex after Its Departure from the Tibetan Plateau 被引量:28
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作者 Shuhua YU Wenliang GAO +1 位作者 Dixiang XIAO Jun PENG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第1期34-46,共13页
Using atmospheric observational data from 1998 to 2013,station rainfall data,TRMM(Tropical Rainfall Measuring Mission) data,as well as annual statistics for the plateau vortex and shear line,the joint activity featu... Using atmospheric observational data from 1998 to 2013,station rainfall data,TRMM(Tropical Rainfall Measuring Mission) data,as well as annual statistics for the plateau vortex and shear line,the joint activity features of sustained departure plateau vortexes(SDPVs) and southwest vortexes(SWVs) are analyzed.Some new and useful observational facts and understanding are obtained about the joint activities of the two types of vortex.The results show that:(1) The joint active period of the two vortexes is from May to August,and mostly in June and July.(2) The SDPVs of the partnership mainly originate near Zaduo,while the SWVs come from Jiulong.(3) Most of the two vortexes move in almost the same direction,moving eastward together with the low trough.The SDPVs mainly act in the area to the north of the Yangtze River,while the SWVs are situated across the Yangtze River valley.(4) The joint activity of the two vortexes often produces sustained regional heavy rainfall to the south of the Yellow River,influencing wide areas of China,and even as far as the Korean Peninsula,Japan and Vietnam.(5) Most of the two vortexes are baroclinic or cold vortexes,and they both become strengthened in terms of their joint activity.(6) When the two vortexes move over the sea,their central pressure descends and their rainfall increases,especially for SWVs.(7) The two vortexes might spin over the same area simultaneously when there are tropical cyclones in the eastern and southern seas of China,or move southward together if a tropical cyclone appears near Hainan Island. 展开更多
关键词 plateau vortex southwest vortex observational study
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Methodological quality(risk of bias)assessment tools for primary and secondary medical studies:What are they and which is better? 被引量:60
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作者 Lin-Lu Ma Yun-Yun Wang +3 位作者 Zhi-Hua Yang Di Huang Hong Weng Xian-Tao Zeng 《Military Medical Research》 SCIE CAS CSCD 2020年第3期359-370,共12页
Methodological quality(risk of bias)assessment is an important step before study initiation usage.Therefore,accurately judging study type is the first priority,and the choosing proper tool is also important.In this re... Methodological quality(risk of bias)assessment is an important step before study initiation usage.Therefore,accurately judging study type is the first priority,and the choosing proper tool is also important.In this review,we introduced methodological quality assessment tools for randomized controlled trial(including individual and cluster),animal study,non-randomized interventional studies(including follow-up study,controlled before-and-after study,before-after/pre-post study,uncontrolled longitudinal study,interrupted time series study),cohort study,case-control study,cross-sectional study(including analytical and descriptive),observational case series and case reports,comparative effectiveness research,diagnostic study,health economic evaluation,prediction study(including predictor finding study,prediction model impact study,prognostic prediction model study),qualitative study,outcome measurement instruments(including patient-reported outcome measure development,content validity,structural validity,internal consistency,cross-cultural validity/measurement invariance,reliability,measurement error,criterion validity,hypotheses testing for construct validity,and responsiveness),systematic review and meta-analysis,and clinical practice guideline.The readers of our review can distinguish the types of medical studies and choose appropriate tools.In one word,comprehensively mastering relevant knowledge and implementing more practices are basic requirements for correctly assessing the methodological quality. 展开更多
关键词 Methodological quality Risk of bias Quality assessment Critical appraisal Methodology checklist Appraisal tool observational study Qualitative study Interventional study Outcome measurement instrument
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Endothelial progenitor cells, potential biomarkers for diagnosis and prognosis of ischemic stroke: protocol for an observational case-control study 被引量:12
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作者 Kamini Rakkar Othman Othman +2 位作者 Nikola Sprigg Philip Bath Ulvi Bayraktutan 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第7期1300-1307,共8页
Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cel... Ischemic stroke is a devastating,life altering event which can severely reduce patient quality of life.Despite years of research there have been minimal therapeutic advances.Endothelial progenitor cells(EPCs),stem cells involved in both vasculogenesis and angiogenesis,may be a potential therapeutic target.After a stroke,EPCs migrate to the site of ischemic injury to repair cerebrovascular damage,and their numbers and functional capacity may determine patients'outcome.This study aims to determine whether the number of circulating EPCs and their functional aspects may be used as biomarkers to identify the type(cortical or lacunar)and/or severity of ischemic stroke.The study will also investigate if there are any differences in these characteristics between healthy volunteers over and under 65 years of age.100 stroke patients(50 lacunar and 50 cortical strokes)will be recruited in this prospective,observational case-controlled study.Blood samples will be taken from stroke patients at baseline(within 48 hours of stroke)and days 7,30 and90.EPCs will be counted with flow cytometry.The plasma levels of pro-and anti-angiogenic factors and inflammatory cytokines will also be determined.Outgrowth endothelial cells will be cultured to be used in tube formation,migration and proliferation functional assays.Primary outcome is disability or dependence on day 90 after stroke,assessed by the modified Rankin Scale.Secondary outcomes are changes in circulating EPC numbers and/or functional capacity between patient and healthy volunteers,between patient subgroups and between elderly and young healthy volunteers.Recruitment started in February 2017,167 participants have been recruited.Recruitment will end in November 2019.West Midlands-Coventry&Warwickshire Research Ethics Committee approved this study(REC number:16/WM/0304)on September8,2016.Protocol version:2.0.The Bayraktutan Dunhill Medical Trust EPC Study was registered in ClinicalTrials.gov(NCT02980354)on November 15,2016.This study will determine whether the number of EPCs can be used as a prognostic or diagnostic marker for ischemic strokes and is a step towards discovering if transplantation of EPCs may aid patient recovery. 展开更多
关键词 ageing biomarkers cortical stroke endothelial progenitor cells ischemic stroke lacunar stroke observational study stem cells
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Observational Study on the Onset of the South China Sea Southwest Monsoon 被引量:5
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作者 阎俊岳 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1997年第2期154-164,共11页
Based on the long-term marine ship observation data, records of meteorological stations and High-Reflective Cloud(HRC) data by satellite remote sensing , this paper has studied the circulation patterns and variability... Based on the long-term marine ship observation data, records of meteorological stations and High-Reflective Cloud(HRC) data by satellite remote sensing , this paper has studied the circulation patterns and variability in elements during onset and the established periods of the South China Sea(SCS) southwest(SW) monsoon. The averaged date of the onset SW monsoon in the SCS occurs in the middle of May climatologically. The corresponding date for the northern part is little earlier (May 12) and those for the southern parts are little later (May 20). The interannual range of the onset dates is about one month. Following the onset of the SW monsoon, the cloud amount and the precipitation increase while the convection activities enhance over the SCS. But there is a strong spatial heterogeneity within the domain. After onset of the SW monsoon the strong convective area moves northwards, while the SCS rain band moves to the center and north. Sea surface temperature(SST) increases rapidly before the onset and the leading time is about one month. The increment of SST supplies heat and vapor for the onset. From April to May the surface heat fluxes display obvious changes, e.g., latent heat exchange and evaporation enhancement. It is one of the reasons why the SW monsoon bursts firstly in the SCS. 展开更多
关键词 South China Sea Southwest monsoon ONSET observational study
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An Observational Study of the 30-50 Day Atmospheric Oscillations Part I: Structure and Propagation 被引量:20
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作者 李崇银 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第3期294-304,共11页
Features of structure and propagation of the 30 to SO day atmospheric oscillations are investigated using the ECMWF analysis of 1980-1983. Evidence is provided to confirm the characteristics of the oscillation in the ... Features of structure and propagation of the 30 to SO day atmospheric oscillations are investigated using the ECMWF analysis of 1980-1983. Evidence is provided to confirm the characteristics of the oscillation in the equatorial region. Those in the mid-high latitudes, however, are revealed to be very different from the tropics and pose a strong barotropic structure. Horizontal coherence shows teleconnection patterns which can be identified as EAP and PNA. The wind field of the specified time scale of the oscillation appears as long-lived vortices and vortex pairs. Mid-latitude perturbations propagate clearly westwards, especially during the winter season. In the high latitudes, they propagate westwards in the winter but eastwards in the summer. Meridional propagations are rather different from region to region. 展开更多
关键词 An observational Study of the 30-50 Day Atmospheric Oscillations Part I HIGH
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Outcomes of different minimally invasive surgical treatments for vertebral compression fractures:An observational study 被引量:3
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作者 Kuei-Lin Yeh Szu-Hsien Wu +2 位作者 Chen-Kun Liaw Sheng-Mou Hou Shing-Sheng Wu 《World Journal of Clinical Cases》 SCIE 2021年第31期9509-9519,共11页
BACKGROUND Osteoporosis with vertebral compression fractures is increasingly common in the elderly population.Cement augmentation is one of the effective surgical treatments for these patients.Currently,there are seve... BACKGROUND Osteoporosis with vertebral compression fractures is increasingly common in the elderly population.Cement augmentation is one of the effective surgical treatments for these patients.Currently,there are several different types of cement augmentation treatments.No studies have compared the safety and efficacy of different cement augmentation types for the treatment of such fractures;thus,we retrospectively compared vertebroplasty,balloon kyphoplasty,and kyphoplasty with SpineJack or an intravertebral expandable pillar.AIM To compare the postoperative safety and efficacy of each surgical intervention in treating vertebral compression fractures.METHODS We retrospectively analyzed 354 patients with acute vertebral compression fractures,defined as signal changes in the T1 weighted magnetic resonance imaging,and randomly divided the patients into five groups.Their visual analog scale scores for pain,kyphotic angle,average body height,rate of cement leakage,and occurrence of adjacent vertebral compression fractures were followed for 1 year.One-way analysis of variance,the post hoc Bonferroni test,and Fisher exact probability test were used for statistical analyses.RESULTS All pain scores significantly improved 12 mo postoperatively;however,there was no significant difference between the groups(P=0.325).Kyphoplasty with SpineJack significantly reduced the kyphotic angle(P=0.028)and restored the height of the vertebral body(P=0.02).The rate of adjacent compression fractures was the highest in the vertebroplasty group,with a statistically significant difference according to the Fisher exact probability test(P=0.02).The treatment with the lowest cement leakage rate cannot be identified because of the small sample size;however,kyphoplasty with SpineJack,an IVEP,and vesselplasty resulted in lower rates of cement leakage than balloon kyphoplasty and vertebroplasty.CONCLUSION Kyphoplasty with SpineJack has good outcomes in kyphotic angle reduction and body height restoration.Vertebroplasty has the highest cement leakage rate and adjacent compression fracture occurrence. 展开更多
关键词 Vertebral compression fracture VERTEBROPLASTY KYPHOPLASTY OSTEOPOROSIS observational study
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A Comparative Observational Study of the Use Transvaginal Ultrasound and Hysteroscopy for the Detection of Uterine Cavity Pathologies in Women with Abnormal Uterine Bleeding 被引量:1
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作者 Mervat Ali Mohamed Elsersy 《Open Journal of Obstetrics and Gynecology》 2017年第5期511-519,共9页
Background: 70% of all gynecological consultations are for abnormal uterine bleeding. Any approach to optimal management begins with an appropriate diagnosis. 40% of premenopausal women with abnormal uterine bleeding ... Background: 70% of all gynecological consultations are for abnormal uterine bleeding. Any approach to optimal management begins with an appropriate diagnosis. 40% of premenopausal women with abnormal uterine bleeding were found to have some intrauterine pathology. This study aims to compare the diagnostic value of transvaginal ultrasonography in comparison to hysteroscopy in detecting uterine abnormalities in patients with abnormal uterine bleeding. Methods: Retrospective observational cross sectional study of 250 women presented with abnormal uterine bleeding. The patients who fulfilled the selection criteria and have been sequentially investigated by transvaginal ultrasound (TVS) and hysteroscopy were included. Results: 90% of patients were from 35 - 49 yrs. 81.2% of patients have body mass index above 25 kg/m2. Transvaginal ultrasound (TVS) compared well with high sensitivity as regards normal endometrium. (TVS) missed 4 patients of endometrial polyps and one patient of sub mucous fibroid. Three patients of adenomyosis were only diagnosed by (TVS);they were reported as being normal by hysteroscopy. Conclusion: (TVS) is considered as an excellent approach to the initial evaluation of uterine pathologies in patients with abnormal uterine bleeding. 展开更多
关键词 TRANSVAGINAL Ultrasound HYSTEROSCOPY Abnormal UTERINE Bleeding Cross Section observational Study ENDOMETRIAL POLYP
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