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The influence of resistance exercise training prescription variables on skeletal muscle mass,strength,and physical function in healthy adults:An umbrella review
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作者 Jonathan C.Mcleod Brad S.Currier +1 位作者 Caroline V.Lowisz Stuart M.Phillips 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期47-60,共14页
Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.Methods:Following ... Purpose:The aim of this umbrella review was to determine the impact of resistance training(RT)and individual RT prescription variables on muscle mass,strength,and physical function in healthy adults.Methods:Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines,we systematically searched and screened eligible systematic reviews reporting the effects of differing RT prescription variables on muscle mass(or its proxies),strength,and/or physical function in healthy adults aged>18 years.Results:We identified 44 systematic reviews that met our inclusion criteria.The methodological quality of these reviews was assessed using A Measurement Tool to Assess Systematic Reviews;standardized effectiveness statements were generated.We found that RT was consistently a potent stimulus for increasing skeletal muscle mass(4/4 reviews provide some or sufficient evidence),strength(4/6 reviews provided some or sufficient evidence),and physical function(1/1 review provided some evidence).RT load(6/8 reviews provided some or sufficient evidence),weekly frequency(2/4 reviews provided some or sufficient evidence),volume(3/7 reviews provided some or sufficient evidence),and exercise order(1/1 review provided some evidence)impacted RT-induced increases in muscular strength.We discovered that 2/3 reviews provided some or sufficient evidence that RT volume and contraction velocity influenced skeletal muscle mass,while 4/7 reviews provided insufficient evidence in favor of RT load impacting skeletal muscle mass.There was insufficient evidence to conclude that time of day,periodization,inter-set rest,set configuration,set end point,contraction velocity/time under tension,or exercise order(only pertaining to hypertrophy)influenced skeletal muscle adaptations.A paucity of data limited insights into the impact of RT prescription variables on physical function.Conclusion:Overall,RT increased muscle mass,strength,and physical function compared to no exercise.RT intensity(load)and weekly frequency impacted RT-induced increases in muscular strength but not muscle hypertrophy.RT volume(number of sets)influenced muscular strength and hypertrophy. 展开更多
关键词 HYPERTROPHY Resistance training Resistance training prescription variables STRENGTH umbrella review
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Impact of citrus fruit and hesperidin intake on multiple health outcomes:An umbrella review
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作者 Yu-Sen Cheng Yong Zhou 《Journal of Nutritional Oncology》 2023年第1期16-24,共9页
Citrus fruits are rich sources of several biologically active flavonoids such as hesperidin,naringin,and polymethoxylated flavones.We evaluated the evidence of associations between citrus fruit or hesperidin intake an... Citrus fruits are rich sources of several biologically active flavonoids such as hesperidin,naringin,and polymethoxylated flavones.We evaluated the evidence of associations between citrus fruit or hesperidin intake and multiple health outcomes.An umbrella review was conducted for studies performed in humans.Overall,246 articles were initially identified by searching in 4 databases.Twenty-two meta-analyses and systematic reviews with 28 health outcomes met the inclusion criteria.Citrus fruit intake had beneficial effects on all-cause mortality(relative risk[RR].0.90;95%confidence interval[95%CI],0.86 to 0.94),cardiovascular diseases(RR,0.78;95%CI,0.66 to 0.92),coronary heart disease(RR,0.91;95%CI,0.86 to 0.96),stroke(RR,0.74;95%CI,0.65 to 0.84),type 2 diabetes mellitus(RR,0.85;95%CI,0.78 to 0.92),and several cancers.Dose-response analyses indicated that each 100-g/d increase in citrus fruit intake could reduce the risks of all-cause mortality by 6%(RR,0.94;95%CI,0.88 to 1.00),stroke by 22%(RR,0.78;95%CI,0.69 to 0.90),and cardia gastric cancer by 40%(RR,0.60;95%CI,0.44 to 0.83).Citrus fruit intake also had beneficial effects on the lipid profile and body weight control(weighted mean difference,−1.28;95%CI,−1.82 to−0.74).Grapefruits could reduce the systolic blood pressure(weighted mean difference,−2.43,95%CI,−4.77 to−0.09).Hesperidin supplementation significantly improved inflammation.Citrus fruit intake was generally safe and beneficial for multiple health outcomes in humans.However,grapefruit and pomelo juice may affect the bioavailability of various medications,so care should be exercised before increasing the intake of these fruits or their juices. 展开更多
关键词 Citrus fruit HESPERIDIN HEALTH umbrella review META-ANALYSIS Systematic review
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Numerical analyses in the design of umbrella arch systems 被引量:3
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作者 J.Oke N.Vlachopoulos M.S.Diederichs 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第6期546-564,共19页
Due to advances in numerical modelling, it is possible to capture complex support-ground interaction in two dimensions and three dimensions for mechanical analysis of complex tunnel support systems,although such analy... Due to advances in numerical modelling, it is possible to capture complex support-ground interaction in two dimensions and three dimensions for mechanical analysis of complex tunnel support systems,although such analysis may still be too complex for routine design calculations. One such system is the forepole element, installed within the umbrella arch temporary support system for tunnels, which warrants such support measures. A review of engineering literature illustrates that a lack of design standards exists regarding the use of forepole elements. Therefore, when designing such support, designers must employ complex numerical models combined with engineering judgement. With reference to past developments by others and new investigations conducted by the authors on the Driskos tunnel in Greece and the Istanbul metro, this paper illustrates how advanced numerical modelling tools can facilitate understanding of the influences of design parameters associated with the use of forepole elements. In addition, this paper highlights the complexity of the ground-support interaction when simulated with two-dimensional(2D) finite element software using a homogenous reinforced region,and three-dimensional(3D) finite difference software using structural elements. This paper further illustrates sequential optimisation of two design parameters(spacing and overlap) using numerical modelling. With regard to capturing system behaviour in the region between forepoles for the purpose of dimensioning spacing, this paper employs three distinctive advanced numerical models: particle codes,continuous finite element models with joint set and Voronoi blocks. Finally, to capture the behaviour/failure ahead of the tunnel face(overlap parameter), 2D axisymmetric models are employed. Finally,conclusions of 2D and 3D numerical assessment on the Driskos tunnel are drawn. The data enriched case study is examined to determine an optimum design, based on the proposed optimisation of design parameters, of forepole elements related to the site-specific considerations. 展开更多
关键词 Forepole umbrella ARCH NUMERICAL MODELLING TUNNEL DESIGN NUMERICAL analysis
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Handgrip strength and health outcomes: Umbrella review of systematic reviews with meta-analyses of observational studies 被引量:6
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作者 Pinar Soysal Christopher Hurst +10 位作者 Jacopo Demurtas Joseph Firth Reuben Howden Lin Yang Mark A.Tully Ai Koyanagi Petre Cristian Ilie Guillermo F.Lopez-Sanchez Lukas Schwingshackl Nicola Veronese Lee Smith 《Journal of Sport and Health Science》 SCIE 2021年第3期290-295,共6页
Purpose:The aim of the present study was to assess both the credibility and strength of evidence arising from systematic reviews with meta-analyses of observational studies on handgrip strength and health outcomes.Met... Purpose:The aim of the present study was to assess both the credibility and strength of evidence arising from systematic reviews with meta-analyses of observational studies on handgrip strength and health outcomes.Methods:An umbrella review of systematic reviews with meta-analyses of observational studies was conducted.We assessed meta-analyses of observational studies based on random-effect summary effect sizes and their p values,95%prediction intervals,heterogeneity,small-study effects,and excess significance.We graded the evidence from convincing(Class I)to weak(Class IV).Results:From 504 articles returned in a search of the literature,8 systematic reviews were included in our review,with a total of 11 outcomes.Overall,nine of the 11 of the outcomes reported nominally significant summary results(p<0.05),with 4 associations surviving the application of the more stringent p value(p<106).No outcome presented convincing evidence.Three associations showed Class II evidence(i.e.,highly suggestive):(1)higher handgrip values at baseline were associated with a minor reduction in mortality risk in the general population(n=34 studies;sample size=1,855,817;relative risk=0.72,95%confidence interval(95%CI):0.670.78),(2)cardiovascular death risk in mixed populations(n=15 studies;relative risk=0.84,95%CI:0.780.91),and(3)incidence of disability(n=7 studies;relative risk=0.76,95%CI:0.660.87).Conclusion:The present results show that handgrip strength is a useful indicator for general health status and specifically for early all-cause and cardiovascular mortality,as well as disability.To further inform intervention strategies,future research is now required to fully understand mechanisms linking handgrip strength scores to these health outcomes. 展开更多
关键词 Handgrip strength Health outcomes META-ANALYSIS umbrella review
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Effect of pipe characteristics in umbrella arch method on controlling tunneling-induced settlements in soft grounds 被引量:6
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作者 Ali Morovatdar Massoud Palassi Reza S.Ashtiani 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第5期984-1000,共17页
Recent developments in tunneling have stimulated design practitioners to more effectively utilize the underground spaces.However,tunneling at shallow depth in soft grounds gives rise to concerns associated with tunnel... Recent developments in tunneling have stimulated design practitioners to more effectively utilize the underground spaces.However,tunneling at shallow depth in soft grounds gives rise to concerns associated with tunnel instability.Umbrella arch method(UAM),as a pre-reinforcement approach of tunnels in complex geological conditions,is widely used to maintain the tunnel stability.Quantitative assessment of the impacts of the entire approach and forepoling pipe features on tunnel stability remains challenging due to the complex nature of the UAM application.This study aimed to assess the effect of pipe design parameters on reinforcing the tunnels excavated in soft grounds.This practical investigation considered the actual field conditions attributed to the tunneling procedure and UAM deployment.Then,the tunneling process was modeled and the tunnel excavation-induced settlements were calculated.The post-processed results confirmed that deploying the UAM substantially reduced the tunnel crown and ground surface settlements by 76%and 42%,respectively.Investigation of various design parameters of pipes underscored the significance of incorporating the optimum value for each individual parameter into design schemes to more effectively control the settlements.Additionally,contrasting the settlement reduction rates(SRRs)for pipe design variables showed that the tunnel stability is more sensitive to the changes in the values of diameter and length,compared to values of the installation angle and center-tocenter distance of the pipes. 展开更多
关键词 Tunnel reinforcement umbrella arch method(UAM) Urban tunneling Forepoling pipes Finite element analysis Numerical simulation
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High-Efficiency Solar Electricity of Umbrella by TRIZ Analysis 被引量:1
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作者 Jung-Hui Chao Cheng-Yu Peng 《Energy and Power Engineering》 2016年第2期51-61,共11页
This investigation presents the strategy of high-efficiency solar electricity of umbrella by TRIZ (Theory of Inventive Problem Solving) analysis. According to the combined statistics of classical and new contradiction... This investigation presents the strategy of high-efficiency solar electricity of umbrella by TRIZ (Theory of Inventive Problem Solving) analysis. According to the combined statistics of classical and new contradiction matrix, the invention principles can be used for designing tracking irradiance of surface plane of umbrella orientations including tilted angle (θ) and azimuth angle (&Oslash;). Three geographical sites are discussed by regions of Berlin, Taipei and Wellington located in north, near and south of tropic of cancer, respectively. The optimal design of azimuth surfaces of umbrella can be obtained by electricity gain at a fixed tilted angle. 展开更多
关键词 TRIZ ELECTRICITY SOLAR ORIENTATION umbrella
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Umbrella with Ultraviolet Radiation Protection
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作者 Kasama Vejakupta Montree Udompataikul 《Journal of Cosmetics, Dermatological Sciences and Applications》 2014年第4期228-233,共6页
Background: Ultraviolet radiation (UVR) causes harm to the eye and skin in human. There are many ways to protect one from UVR. Umbrella is widely used due to its convenience as well as its ability to protect one from ... Background: Ultraviolet radiation (UVR) causes harm to the eye and skin in human. There are many ways to protect one from UVR. Umbrella is widely used due to its convenience as well as its ability to protect one from rain. However, there are limited numbers of studies on UVR protection of different types of umbrellas. Objective of study: To determine UVR protection efficacy of different umbrella designs. Methods: The experimental study was performed on five sunny days. Six manikins were placed in an open area, five of which were equipped with five different types of black canopy umbrellas. One manikin was placed without an umbrella as a control sample. Polysulfone film badges were attached in six different areas in each manikin for measuring the UVR from 10 am - 3 pm Results: All types of umbrellas provides 64.5% - 92.3% UVR photo protection efficacy. An umbrella with UV-filter coating on the inner surface provides maximum UVR photo protection efficacy. However, UVR proto protection efficacies of an umbrella with UV-filter coating on the inner surface and one with UV-filter coating on the outer surface and one without UV-filter coating are not statistically significant (p-value = 0.37). Umbrellas with a diameter of 122 cm and 152 cm provide comparable UVR photo protection efficacy while an umbrella with a diameter of 112 cm provides the least UVR photo protection efficacy. However, UVR photo protection efficacies of umbrellas with different diameter are not statistically significant (p-value = 0.36). The area of the body that received the most UVR photo protection is the forehead which is statistically significant when compared with other areas of the body (p-value < 0.001). The areas of the body that received the least UVR photo protection are the left ear and the back of the neck, which are statistically significant when compared with other areas of the body (p-value < 0.001). Conclusion: All types of umbrellas provide UVR photo protection efficacy. The study shows that umbrellas with different canvas material including both the UV-filter coating and different diameter of umbrellas could effectively protect the user from UVR without significant group difference in this study. 展开更多
关键词 umbrella ULTRAVIOLET Protection FILTER COATING RADIUS
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An umbrella review of Lianhua Qingwen combined with Western medicine for the treatment of coronavirus disease 2019
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作者 Kelu Yang Jiaoyan Zhang +5 位作者 Liang Zhao Luying Cheng Yuanyuan Li Yuchen Kang Xiangyu Zhang Yingying Kang 《Acupuncture and Herbal Medicine》 2022年第3期143-151,共9页
Objective:Lianhua Qingwen combined with Western medicine(LHQW+WM)has been proposed as a viable treatment for coronavirus disease 2019(COVID-19).Interestingly,umbrella reviews of systematic reviews(SRs),which provide t... Objective:Lianhua Qingwen combined with Western medicine(LHQW+WM)has been proposed as a viable treatment for coronavirus disease 2019(COVID-19).Interestingly,umbrella reviews of systematic reviews(SRs),which provide the most comprehensive evidence,are the best evidence in evidence-based medicine.Therefore,an umbrella review of SRs that summarizes and evaluates the efficacy of LHQW+WM for COVID-19 is urgently required.Methods:Overall,6 databases were used to conduct a comprehensive literature search from inception to January 22,2022.The corrected covered area(CCA)was used to analyze the overlapping between SRs.Meta-analysis was conducted when that of the included SRs was inappropriate.A MeaSurement Tool to Assess Systematic Reviews(AMSTAR-2)was also employed to assess the quality of the included SRs.Results:In total,12 SRs were identified,which included 12 unique primary studies.The included SRs ranged in quality from moderate to critically low and had an extremely high CCA(36.4%).Compared to conventional treatment,LHQW+WM showed efficacy concerning fatigue recovery[risk ratio(RR)=1.69,95%confidence interval(CI):1.04-2.73,n=2,I2=0%],cough recovery(RR=1.65,95%CI:1.09-2.51,n=3,I2=39.1%),and overall effective rates(RR=1.17,95%CI:1.07-1.28,n=3,I2=17.5%).Conclusion:LHQW+WM may improve the clinical symptoms of patients with COVID-19;however,the results should be interpreted cautiously because of the rigorous processes in the included SRs. 展开更多
关键词 COVID-19 Lianhua Qingwen META-ANALYSIS umbrella review
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Umbrella Arching and Compensation Grouting in Order to Protect Settlement-Sensitive Buildings over Large Shotcrete Excavations in Gravel
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作者 Habil.Jochen Fillibeck Andy Klinger +1 位作者 Martin Sailer Stephan Geuder 《Journal of Civil Engineering and Architecture》 2022年第2期53-66,共14页
The Tunnel Oberau, with a length of 2.9 km, forms the core of the local bypass of Oberau. Between the two massifs Kirchbichl and Mühlberg, the tunnel is situated in the valley of the Gießenbach in alluvial g... The Tunnel Oberau, with a length of 2.9 km, forms the core of the local bypass of Oberau. Between the two massifs Kirchbichl and Mühlberg, the tunnel is situated in the valley of the Gießenbach in alluvial gravel with only a small overlap underneath settlement-sensitive buildings. In this paper, the measures in the tunnel to minimize the settlements of the buildings during the shotcrete excavations are described. Basis for this planning were extensive 3D-FE-calculations. Furthermore, under two buildings a compensation grouting measure was carried out, in order to compensate the occurring settlements. This paper describes how the required time and the amount of injection material (grout) could be reduced during the compensation grouting in highly permeable gravel. 展开更多
关键词 umbrella arching shotcrete excavation compensation grouting excavation in gravel
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The Types of Tunnels Maintenance in Umbrella Arch Method
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作者 Arash Rostami Parham Kamali Dehkordi +2 位作者 Morteza Askari Ziarati Saman Jahani Kamran Lotfi 《Open Journal of Civil Engineering》 2016年第2期156-162,共7页
During tunneling in loose grounds, the ground deformation caused by drillings around the tunnel, leads to land subsidence and the adjacent tunnel which would affect tunnel structure and surrounding structures. In such... During tunneling in loose grounds, the ground deformation caused by drillings around the tunnel, leads to land subsidence and the adjacent tunnel which would affect tunnel structure and surrounding structures. In such situations it is necessary to improve the properties of the ground prior to drilling operations. In order to acquire tunnel face stability during excavation operations in areas with loose soil fault or areas with lack of adhesion, there are various methods such as split cross drilling, frame holder or auxiliary pre-holding methods such as umbrella arch method;pre-holding methods must provide safety when drilling and must be affordable, economically. In this study, we assessed the previous studies on methods and behaviors of umbrella arch strategy in reinforcing the concrete tunnels, reached the purpose with experimental and numerical methods and offered the latest design achievements, implementation progresses and analysis in relation with this method. 展开更多
关键词 TUNNEL DRILLING umbrella Arch Method Forepole ARMING
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Pollutant exposure and health outcomes:protocol for a comprehensive umbrella review of meta-analyses and evidence mapping
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作者 Jing Qi Lufang Feng +6 位作者 Jiemei Hu Haitong Zhao Jieyun Li Lixin Ke Xue Shang Kehu Yang Cuncun Lu 《Asian Toxicology Tesearch》 2021年第3期12-17,共6页
Background:Many systematic reviews and meta-analyses(MAs)regarding the association between pollutant(e.g.,air pollution,noise pollution,and heavy metal pollution)exposure and health outcomes have been published recent... Background:Many systematic reviews and meta-analyses(MAs)regarding the association between pollutant(e.g.,air pollution,noise pollution,and heavy metal pollution)exposure and health outcomes have been published recently,but there is still a lack of comprehensive research based on these MAs,and the evidence quality of these MAs are unknown.Therefore,we designed an umbrella review to address these gaps in knowledge.Methods:MAs that evaluated the association between pollutant exposure and health outcomes will be systematically searched through the PubMed and Embase databases in May 2021.Pairs of reviewers will conduct the study screening and data extraction independently,and cross-check the results.PRISMA and AMSTAR 2 will be used to evaluate the reporting and methodological quality of MAs included,respectively,and an evidence mapping method will be used to present the results.The corrected cover area(CCA)method will be used to assess the degree of overlap for included primary studies among MAs.The outcomes will be reanalyzed based on the random-effects model using the appropriate effect size,and the corresponding 95%confidence intervals will be reported.Meanwhile,sensitivity analysis and subgroup analysis will be used to explore heterogeneity.The GRADE method will be used to evaluate the evidence quality of outcome indicators.Stata 16.0 and Excel 2019 will be used for data analysis,and P<0.05 will be considered to indicate statistical significance.Results:The results of this umbrella review will be submitted to a peer-reviewed English journal for publication.Conclusion:We designed the first umbrella review to summarize evidence from MAs on the association between common pollutant exposure and health conditions.The results of this study will provide evidence for health policy makers to formulate appropriate health policies and researchers to conduct new studies. 展开更多
关键词 Air pollution Noise Heavy metal umbrella review META-ANALYSES
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Oral Contraceptives and Health Outcomes:an Umbrella Review of Systematic Reviews and Meta-analyses in Women and Offspring
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作者 Yuan Lin Zou Rui Peng +3 位作者 Ke Di Xu Xiao Ru Jiang Qiu Yu Sun Chun Hua Song 《Journal of Nutritional Oncology》 2022年第1期9-37,共29页
Aim We herein provide an umbrella review of systematic reviews(SR)and meta-analyses(MAs)of studies of the association of oral contraceptives(OCs)with the risks of multiple health outcomes in women and their descendant... Aim We herein provide an umbrella review of systematic reviews(SR)and meta-analyses(MAs)of studies of the association of oral contraceptives(OCs)with the risks of multiple health outcomes in women and their descendants.Methods Two investigators retrieved publications from four electronic databases,including PubMed,Embase,Web of Science,and the Cochrane Database of Systematic Reviews up to March 15,2021.For each association,random/fixed-effects summary effect size and 95%CIs were estimated.Heterogeneity and publication bias were also assessed.The method quality and evidence level for each publication were respectively assessed utilizing the AMSTAR and GRADE checklists.Results A total of 68 articles with 82 unique outcomes were included based on the eligibility criteria.Numerous lines of evidence indicated that OCs had effects on nearly all cardiovascular disease-related outcomes,especially for cerebral venous sinus thrombosis(OR=7.59,95%CI:3.82-15.09).Harmful associations were also found for vulvar vestibulitis(OR=2.31,95%CI:1.03-5.16),preterm birth(OR=1.17,95%CI:1.07-1.27),miscarriage(OR=1.13,95%CI:1.02-1.72),ulcerative colitis(OR=1.22,95%CI:1.06-1.41),Crohn's disease(OR=1.24,95%CI:1.09-1.40),alveolar osteitis(RR=1.86,95%CI:1.66-2.08),dry socket(RR=1.8,95%CI:1.33-2.43),and interstitial cystitis(OR=2.1,95%CI:1.26-3.49).However,oral contraceptives did not increase the risk of cancer except breast and cervical cancer.Maternal exposure to OCs was linked to an increased risk for the development of respiratory atopic disorders such as asthma(OR=1.1,95%CI:1.02-1.19)and rhinitis(OR=1.34,95%CI:1.07-1.68).Conclusion In summary,although their use obviously reduces the risk of pregnancy-and parturition-related morbidity and mortality for women,OCs were frequently related to more harm than benefit in terms of other health outcomes.This was true for both women and their descendants in this umbrella review.More large-scale prospective studies analysing different doses,structures,and durations of treatment with estrogen and progestin are needed to confirm these effects. 展开更多
关键词 CONTRACEPTION Health outcomes umbrella review META-ANALYSIS Systematic review
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UMBRELLA 最美不是下雨天,是我独自撑起的那片“晴空”
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《课堂内外(高中版)(A版)》 2016年第9期82-83,共2页
一把伞,就像是一道屏障,把所有的悲伤、孤独、阳光、雨水都隔离开来,那一方小小的阴影下,就是一个独立的世界,任凭时移势迁,我自岿然。
关键词 umbrella 阴影下
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Umbrella
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作者 严时田 《疯狂英语(初中天地)》 2002年第42期8-8,共1页
Yesterday my father went to work by 1,but he left his umbrella(雨伞) in one of the compartments(火车车厢).He told the 2 about it and they began to look for the umbrella."3 compartment did you leave your umbrella ... Yesterday my father went to work by 1,but he left his umbrella(雨伞) in one of the compartments(火车车厢).He told the 2 about it and they began to look for the umbrella."3 compartment did you leave your umbrella in?" the conductor asked.But my fathercouldn't 4. The conductor found an 展开更多
关键词 umbrella
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Umbrella
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作者 严时田 《疯狂英语(初中天地)》 2002年第46期8-8,共1页
Yesterday my father went to work by 1 ,but he left his umbrella(雨伞)in one of thecompartments(火车车厢).He told the 2 aboutit and they began to look for time umbrella.
关键词 umbrella
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CFD simulation on performance of new type umbrella plate scrubber
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作者 李珊红 李彩亭 +3 位作者 曾光明 李思民 王飞 王大勇 《中国有色金属学会会刊:英文版》 EI CSCD 2008年第2期488-492,共5页
A new type of umbrella plate scrubber was developed to address the pollution due to the dust,dioxide sulfur and other harmful gases,which were emitted from coal-burning boilers.The performance of the new device was st... A new type of umbrella plate scrubber was developed to address the pollution due to the dust,dioxide sulfur and other harmful gases,which were emitted from coal-burning boilers.The performance of the new device was studied through computational fluid dynamics(CFD)simulation and experiment methods.Initial work included experimental measurement of inlet-velocity,and gas phase simulation using Reynolds stress model(RSM).After gas phase was converged,particles were injected from the inlet of the new device.Discrete phase model(DPM)was used for particle trajectories determination.The pressure drop and the collection efficiency of the new device were predicted through simulation.The simulation results show that the pressure drop of the new devices is 230?250 Pa and the efficiency is 84%-86%,with the inlet velocity equal to 10.6 m/s and the dust concentration ranging from 2 to 22 g/m 3 .The CFD simulation results of the new device show good agreement with experimental data.The relative error of the pressure drop and the efficiency is approximately 4%and 10%respectively.The results obtained both from the numerical simulation and from the experiment demonstrate that CFD simulation is an effective method for this type of study. 展开更多
关键词 模拟技术 分散相 二氧化物 污染物 环境保护
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A Generalized Information Criterion for Parameters under an Umbrella Order Restriction
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作者 宋海燕 陶剑 史宁中 《Northeastern Mathematical Journal》 CSCD 2005年第2期127-130,共4页
The detection of the configuration of parameters is one of the most important problems im statistical studies. It is well known that the Akaike's information criterion (AIC) is a key tool for this problem (see [1]... The detection of the configuration of parameters is one of the most important problems im statistical studies. It is well known that the Akaike's information criterion (AIC) is a key tool for this problem (see [1]). Usually, the AIC is defined as: AIC(μ^) := l(μ^) -p, where l(μ^) is the log-likelihood with the maximum likelihood estimator (MLE) μ for μ, 展开更多
关键词 广义信息标准 参数构造 标准概率 伞形序列 AIC 最大相估计
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Associations between the use of red yeast rice preparations and adverse health outcomes:An umbrella review of meta-analyses of randomized controlled trials
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作者 Zhen-yu Ma Shu-ping Yang +7 位作者 Ying Li Tian-tian Xu Ya-lin Yang Hui-yong Yang Heng-bing Li Le-jin Zhou Yong Diao Su-yun Li 《Journal of Integrative Medicine》 SCIE CAS CSCD 2024年第2期126-136,共11页
Background:Red yeast rice(RYR),a natural lipid-lowering agent,is widely used in clinical practice.However,the existing meta-analyses concerning the safety of RYR preparations have yielded inconsistent results,and the ... Background:Red yeast rice(RYR),a natural lipid-lowering agent,is widely used in clinical practice.However,the existing meta-analyses concerning the safety of RYR preparations have yielded inconsistent results,and the credibility of the evidence has not been quantified.Objective:This study was designed to evaluate the existing evidence and offer a comprehensive understanding of the associations between the use of RYR preparations and various adverse health outcomes.Search strategy:Seven literature databases were searched from inception to May 5,2023,using medical subject headings and free-text terms(e.g.,“red yeast rice,”“Xuezhikang,”and“Zhibitai”).Inclusion criteria:Meta-analyses that investigated and quantitatively estimated associations between the use of RYR preparations and adverse health outcomes were included in this study.Data extraction and analysis:Two researchers independently extracted data using a standardized data collection table;any disagreements were resolved by consulting a third researcher.Based on the participant,intervention,comparator and outcome(PICO)framework in each eligible meta-analysis,a series of unique associations between the use of RYR preparations and adverse health outcomes were determined.The associations’effect estimates were re-evaluated using random-effect models.Results:Fifteen meta-analyses,comprising 186(164 unique)randomized controlled trials,were identified.Based on A Mea Surement Tool to Assess Systematic Reviews version 2,3(20%)and 12(80%)of these meta-analyses had low and critically low confidence,respectively.A total of 61 unique associations between the use of RYR preparations and adverse health outcomes were extracted from eligible metaanalyses.Based on the random-effect models,10(16.4%)associations indicated a significant protective effect of RYR preparations against adverse health outcomes,while 5(8.2%)indicated an increased risk of adverse health outcomes related to uric acid,alanine transaminase and aspartate transaminase levels.The other 46(75.4%)associations showed no significant difference between the use of RYR preparations and control treatments.Regarding the credibility of the evidence,21(34.4%),34(55.7%)and 6(9.8%)associations showed moderate,low and very low credibility,respectively.Conclusion:The evidence examined in this study suggests that RYR preparations are safe;however,the credibility of the evidence was not high.Further high-quality evidence is required. 展开更多
关键词 Red yeast rice SAFETY Adverse health outcomes umbrella review META-ANALYSIS Systematic review
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Acupuncture and moxibustion for irritable bowel syndrome:An umbrella systematic review
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作者 Yue-ying Ma Zhou Hao +4 位作者 Zi-yi Chen Yan-xi Shen Hui-rong Liu Huan-gan Wu Chun-hui Bao 《Journal of Integrative Medicine》 SCIE CAS CSCD 2024年第1期22-31,共10页
BackgroundIrritable bowel syndrome(IBS)is a functional bowel disease characterized by abdominal pain or discomfort associated with altered bowel habits.Several clinical studies have demonstrated the effectiveness of a... BackgroundIrritable bowel syndrome(IBS)is a functional bowel disease characterized by abdominal pain or discomfort associated with altered bowel habits.Several clinical studies have demonstrated the effectiveness of acupuncture and moxibustion for IBS.Many systematic reviews of acupuncture and moxibustion for IBS have been published in recent years,but their results are not entirely consistent.ObjectiveTo evaluate the methodological,reporting,and evidence quality of systematic reviews of acupuncture and moxibustion for IBS.Search strategySystematic reviews of acupuncture and moxibustion for IBS published before February 20,2023 were searched in eight databases:PubMed,Embase,Cochrane Library,Web of Science,China National Knowledge Infrastructure,Wanfang Data,VIP Database for Chinese Technical Periodicals,and China Biology Medicine.The keywords used for literature search were acupuncture,moxibustion,systematic review,meta-analysis,and irritable bowel syndrome.Inclusion criteriaSystematic reviews and meta-analyses of randomized controlled trials of acupuncture and moxibustion for IBS were included.Data extraction and analysisRelevant information was independently extracted by two investigators.The A MeaSurement Tool to Assess systematic Reviews 2(AMSTAR 2),Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA 2020),and Grading of Recommendations Assessment,Development and Evaluation(GRADE)were used to evaluate the methodological quality,reporting quality and evidence quality,respectively.ResultsA total of 342 studies were retrieved and 15 systematic reviews were included.The results of AMSTAR 2 showed low methodological quality in 2 studies and very low methodological quality in the remaining 13 studies,with main issues being failure to register a protocol,incomplete search strategy,not providing a list of excluded studies,incomplete consideration of the risk of bias in the included studies,and a failure to assess the publication bias.The results of PRISMA 2020 showed seriously deficient reporting quality of 2 studies,somewhat deficient reporting quality of 12 studies,and relatively complete reporting quality of 1 study,with the main problems being lack of a complete search strategy,non-availability of a list of excluded studies with justification for their exclusion,not conducting heterogeneity and sensitivity analyses,not evaluating the credibility of the evidence,and not registering the protocol.The results of GRADE showed that the quality of the evidence is low or very low.ConclusionMost included systematic reviews interpreted findings to suggest that acupuncture and moxibustion have benefits for IBS.However,there is a need to improve the methodological,reporting and evidence quality of the systematic reviews.Larger,multicenter,rigorously designed randomized controlled trials and high-quality systematic reviews are required to obtain more robust evidence. 展开更多
关键词 Irritable bowel syndrome ACUPUNCTURE MOXIBUSTION umbrella systematic review Systematic review
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Association between antibiotic exposure and adverse outcomes of children and pregnant women: evidence from an umbrella review 被引量:1
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作者 Ya Li Lin-Hu Liu +4 位作者 Zhong-Yu Jian Pu-Han Li Xi Jin Hong Li Kun-Jie Wang 《World Journal of Pediatrics》 SCIE CSCD 2023年第12期1139-1148,共10页
Background Antibiotics are widely prescribed among children and pregnant women,but their safety profile is controversial.This study aimed to summarize and appraise current evidence for the potential impact of antibiot... Background Antibiotics are widely prescribed among children and pregnant women,but their safety profile is controversial.This study aimed to summarize and appraise current evidence for the potential impact of antibiotic exposure on pregnancy outcomes and children’s health.Methods PubMed,Embase,Web of Science and the Cochrane Database of Systematic Reviews were searched from inception to June 2022.Meta-analyses of any study design comparing the impact of antibiotic exposure with nonexposure among children,pregnant women and prepregnant women on adverse health outcomes of children and pregnancy were retrieved.The quality of evidence was assessed by a Measurement Tool to Assess Systematic Reviews 2(AMSTAR2)and the Grading of Recommendations,Assessment,Development and Evaluation(GRADE).Data were reanalyzed,and the credibility of the evidence was determined.Results Out of 2956 studies identified,19 articles with 39 associations were included.Totally 19 of the associations(48.72%)were statistically significant with a P value≤0.05,while only six were supported by highly suggestive evidence.Children with postnatal antibiotic exposure had a higher risk of developing asthma odds ratio(OR):1.95,95%confidence interval(CI):1.76–2.17,wheezing(OR:1.81,95%CI 1.65–1.97)and allergic rhinoconjunctivitis(OR:1.66,95%CI 1.51–1.83),with prediction intervals excluding the nulls.Quality assessed by both AMSTAR2 and GRADE of included meta-analyses were very low in general.Conclusions Antibiotic exposure in early life was associated with children’s long-term health,especially in cases of allergic diseases.Prenatal exposure might also influence children’s health in some aspects but requires more high-quality evidence.Potential adverse effects of antibiotics on pregnancy outcomes were not observed in our study.Studies with higher quality and better quantification of antibiotic exposure are needed in the future. 展开更多
关键词 Antibiotic exposure Gut microbiome Prenatal exposure Postnatal exposure umbrella review
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