期刊文献+
共找到46,753篇文章
< 1 2 250 >
每页显示 20 50 100
Screening dual variable-valence metal oxides doped calcium-based material for calcium looping thermochemical energy storage and CO_(2)capture with DFT calculation 被引量:1
1
作者 Youhao Zhang Yi Fang +4 位作者 Zhiwei Chu Zirui He Jianli Zhao Kuihua Han Yingjie Li 《Journal of Energy Chemistry》 2025年第8期170-182,共13页
The reaction characteristics of calcium-based materials during calcium looping(CaL)process are pivotal in the efficiency of CaL thermochemical energy storage(TCES)and CO_(2)capture systems.Currently,metal oxide doping... The reaction characteristics of calcium-based materials during calcium looping(CaL)process are pivotal in the efficiency of CaL thermochemical energy storage(TCES)and CO_(2)capture systems.Currently,metal oxide doping is the primary method to enhance the reaction characteristics of calcium-based materials over multiple cycles.In particular,co-doping with variable-valence metal oxides(VVMOs)can effectively increase the oxygen vacancy content in calcium-based materials,significantly improving their cyclic reaction characteristics.However,there are so numerous VVMOs co-doping schemes that the experimental screening process is complex,consuming considerable time and economic costs.Density functional theory(DFT)calculations have been widely used to reveal the impact of metal oxide doping on the cyclic reaction characteristics of calcium-based materials,with calculation results showing good agreement with experimental conclusions.Nevertheless,there is still a lack of research on utilizing DFT to screen calcium-based materials,and a systematic research methodology has not yet been established.In this study,a systematic DFT-based screening methodology for calcium-based materials was proposed.A series of key parameters for DFT calculations including CO_(2)adsorption energy,oxygen vacancy formation energy,and sintering resistance were proposed.Furthermore,a preliminary mathematical model to predict the CaL TCES and CO_(2)capture performance of calcium-based materials was introduced.The aforementioned DFT method was employed to screen for VVMOs co-doped calcium-based materials.The results revealed that Mn and Ce co-doped calcium-based materials exhibited superior DFT-predicted reaction characteristics.These DFT predictions were validated through experimental assessments of cyclic thermochemical energy storage,CO_(2)capture,and relevant characterization.The outcomes demonstrate a high degree of consistency among DFT-based predictions,experimental results,and characterization.Hence,the DFT-based screening methodology for calcium-based materials proposed herein is a viable solution,poised to offer theoretical insights for the efficient design of calcium-based materials. 展开更多
关键词 Density functional theorу Calcium looping Material screening Variable-valence metal oxide CO_(2)capture Thermochemical energy storage
在线阅读 下载PDF
Reporting quality of randomized controlled trials on acupuncture and manipulation for greater occipital neuralgia evaluated using the CONSORT statement and STRICTA checklist
2
作者 Liu Liguo Qiu Mingwang +3 位作者 Huang Yanling Fan Zhiyong Wu Shan Guo Rusong 《中国组织工程研究》 北大核心 2025年第30期6566-6573,共8页
OBJECTIVE:In recent years,the number of clinical research reports on acupuncture and manipulation for the treatment of greater occipital neuralgia has gradually increased,but the quality is uneven.There is currently n... OBJECTIVE:In recent years,the number of clinical research reports on acupuncture and manipulation for the treatment of greater occipital neuralgia has gradually increased,but the quality is uneven.There is currently no literature evaluating the quality of published reports,which is not conducive to the promotion of clinical use of these therapies.Therefore,this article assessed the reporting quality of randomized controlled trials on acupuncture and manipulation for greater occipital neuralgia.METHODS:Cochrane Library,PubMed,Web of Science,Embase,China National Knowledge Infrastructure(CNKI),VIP,WanFang Data,and Chinese BioMedical Literature Database(CBM)from inception to May 20,2024 were searched.The reporting quality of included randomized controlled trials was independently evaluated by two investigators using the CONSORT statement,STRICTA checklist,and Cochrane bias of risk assessment tool.A third investigator resolved any disagreement.RESULTS:A total of 62 articles were included.Based on the CONSORT statement,59.46%(22/37)of all entries had a reporting rate of less than 50%,mainly including“Identification as a randomized trial in the title(1/62,1.61%),”“How sample size was determined(7/62,11.29%),”“Implementation(1/62,1.61%),”“Blinding(1/62,1.61%),”and“Reports of Funding(4/62,6.45%).”According to the STRICTA checklist,29.41%(5/17)of all entries had a reporting rate of less than 50%,mainly including“Details of other interventions(7/58,12.07%),”“Setting and context of treatment(0/58,0%),”and“Description of participating acupuncturists(0/58,0%).”CONCLUSION:The reporting quality of randomized controlled trials on acupuncture and manipulation therapy for greater occipital neuralgia remains low.Future researchers need to make greater efforts to strictly adhere to the CONSORT statement and STRICTA checklist during trial design,implementation,and reporting.This will facilitate the standardization of research in this field and enhance the reliability and reproducibility of the research results. 展开更多
关键词 reporting quality ACUPUNCTURE MANIPULATION CONSORT statement STRICTA checklist ROB clinical randomized controlled trials greater occipital neuralgia
暂未订购
Short bouts of accumulated exercise:Review and consensus statement on definition,efficacy,feasibility,practical applications,and future directions 被引量:1
3
作者 Mingyue Yin Yongming Li +43 位作者 Abdul Rashid Aziz Aidan Buffey David J.Bishop Dapeng Bao George P.Nassis Hashim Islam Hongying Wang Jackson J.Fyfe Jianfang Xu Jianxiu Liu Jiexiu Zhao Jingwei Cao Jonathan P.Little Junqiang Qiu Keith M.Diaz Lijuan Wang Liye Zou Max J.Western Meynard L.Toledo Min Hu Minghui Quan Neville Owen Niels B.J.Vollaard Olivier Girard Qingde Shi Richard S.Metcalfe Rodrigo Ramirez-Campillo Ru Wang Waris Wongpipit Weimo Zhu Wenfei Zhu Weigang Xu Xiaochun Wang Xiaoping Chen Xiong Wang Xu Wen Yang Liu Ying Gao Yue Fu Zhaowei Kong Zhenbo Cao Zhengzhen Wang Peijie Chen Lijuan Mao 《Journal of Sport and Health Science》 2026年第2期1-30,共30页
Background:Insufficient physical activity and prolonged sedentary behavior have emerged as major global public health challenges.Short bouts(≤10 min)of accumulated exercise(SBAE)throughout the day may be a promising ... Background:Insufficient physical activity and prolonged sedentary behavior have emerged as major global public health challenges.Short bouts(≤10 min)of accumulated exercise(SBAE)throughout the day may be a promising strategy to mitigate the adverse effects of prolonged sitting and promote physical activity,ultimately promoting overall health.However,previous ambiguity in defining this concept has resulted in a fragmented and inconsistent evidence base,impeding practical applications,the development of guidelines,and policymaking.The purpose of this study is to establish an operational definition of SBAE by synthesizing systematic reviews and research trials alongside an expert consensus.Additionally,it seeks to evaluate acute and long-term efficacy and feasibility,providing evidence-based recommendations for practice and future research directions.Methods:A literature search was performed across PubMed and Web of Science,followed by systematic screening and summarization of eligible studies based on predefined inclusion criteria.Inclusion criteria encompassed various modes/types of SBAE(bouts lasting≤10 min,performed multiple times daily with≥30 min intervals);both aerobic and resistance exercise were considered.Relevant systematic reviews and research trials were included.Methodological quality,risk of bias,and evidence certainty were assessed.Expert consensus was obtained through a survey to evaluate recommendations and agreement levels on findings.Results:After analyzing 27 systematic reviews,135 research studies,and an expert consensus involving 48 researchers from 11 countries,SBAE is defined as any exercise mode of activity,regardless of intensity,that is accumulated in either continuous or intermittent bouts lasting≤10 min per session(including multiple intermittent sets)that are performed multiple times(≥2 sessions/day)per day,with intervals of≥30 min between bouts or otherwise sufficient time for recovery.When used to interrupt prolonged periods of sedentary time,SBAE mitigates the acute adverse effects of sedentary behavior on more than 10 clinical biomarkers of endocrine,cardiovascular,and brain health/function among adults of diverse ages and conditions.Moreover,SBAE was superior for improving acute glycemic control compared to a single continuous exercise session.As a long-term intervention(average of 11 weeks),SBAE can improve over 20 health outcomes,including peak oxygen uptake,resting blood pressure,and metabolic health.Additionally,SBAE might be more effective than continuous exercise for improving longer-term glycemic control and body composition.Long-term completion rates for SBAE interventions are generally high(95%),with low dropout rates(12%)and high adherence rates even without supervision(85%),and its safety has been preliminarily validated.Conclusion:An operational definition of SBAE is provided along with its classification and acute and long-term efficacy.Practical exercise prescription recommendations and evidence-based strategies for various populations and contexts are provided.Future research should focus on generating high-quality evidence for SBAE in 5 key areas:quantification and monitoring,population-specific responses,optimization of exercise prescriptions,intervention efficacy,and practical implementation.Additionally,addressing policy,environmental,and promotional barriers is crucial for transitioning from expert consensus to public consensus,and for facilitating the application of this strategy in real-world environments. 展开更多
关键词 Short bouts of accumulated exercise Exercise snacks Consensus statement Sedentary breaks
在线阅读 下载PDF
Impact of feedback loop parameter settings on the stability margin in a double radio-frequency system
4
作者 Yu-Bing Shen Qiang Gu +1 位作者 Hong-Tao Hou Zhi-Gang Zhang 《Nuclear Science and Techniques》 2025年第6期66-79,共14页
Most synchrotron light storage rings are equipped with a higher harmonic cavity(HHC)and are currently predominantly used to increase beam life.With the enhancement of the beam current intensity,it is necessary to cons... Most synchrotron light storage rings are equipped with a higher harmonic cavity(HHC)and are currently predominantly used to increase beam life.With the enhancement of the beam current intensity,it is necessary to consider instability problems that may be caused by heavy beam loading effects.In this study,we incorporated a HHC into the small-signal Pedersen mathematical model and used system signal analysis to investigate the mode-zero Robinson instability driven by the passive superconducting harmonic cavity and active superconducting harmonic cavity fundamental modes.To further study and alleviate this instability,we introduced direct radio-frequency feedback,an automatic voltage control loop,and a phase-lock loop into the model,discussed the impact of the feedback loop parameter settings on the stability margin,and provided suggestions for parameter settings. 展开更多
关键词 double RF system RF system loop instability Pedersen model
在线阅读 下载PDF
Nanoconfinement-engineered iron-based redox catalysts:Precise shell thickness gradients enhanced durability of chemical looping hydrogen production
5
作者 Yang Li Da Song +9 位作者 Yuchao Zhou Juan Fu Zheng Liang Shengwang Mo Yan Lin Shengxi Zhao Hongyu Huang Fang He Cuiqin Li Zhen Huang 《Journal of Energy Chemistry》 2025年第7期1046-1055,共10页
Hydrogen energy,as the ultimate clean energy,effectively avoids the greenhouse effect.Chemical looping hydrogen production(CLHP),a versatile energy conversion and production technology,has garnered extensive attention... Hydrogen energy,as the ultimate clean energy,effectively avoids the greenhouse effect.Chemical looping hydrogen production(CLHP),a versatile energy conversion and production technology,has garnered extensive attention.CLHP demands redox catalysts with high oxygen capacity,regulatable reactivity,and structural integrity even under harsh operational conditions.Currently,sintering,agglomeration,and inactivation of redox catalysts during cyclic lattice oxygen release and restoration are challenging,hindering the wide industrialization of the chemical looping(CL)process.Moreover,the precise control of activity and reaction rate of the redox catalysts to flexibly accommodate the demands of various reaction substrates remains unclear.This paper introduces the design of a nano-scaled redox catalyst featuring a unique core-shell structure.By precisely controlling the shell thickness,a series of hierarchical Fe_(2)O_(3)@SiO_(2)redox catalysts were successfully synthesized.Building on this achievement,an in-depth investigation was conducted into the impact of the thickness and spatial structure of the inert support on the stability and mass transfer rate of the redox catalyst,aiming to achieve a perfect balance between these two factors during the CLHP process.A thin shell(70 nm)exhibits excellent cyclic stability,maintaining consistent performance in 30 consecutive redox cycles,while a thicker shell(200 nm)undergoes rapid deactivation due to the formation of a substantial amount of iron silicate.In-situ transmission electron microscopy(TEM)reveals that the SiO_(2)shell effectively restricts the agglomeration of Fe_(2)O_(3).The unique core-shell structure and controllable shell thickness offer novel insights into the flexible design of efficient and durable hierarchical redox catalysts with spatial structure. 展开更多
关键词 Hydrogen energy Chemical looping hydrogen production Core-shell structure Hierarchical redox catalyst Stability and mass transferrate
在线阅读 下载PDF
A study of feedback loop mechanisms regulating calcium,IP_(3) and dopamine in neurons
6
作者 Anand Pawar Kamal Raj Pardasani 《Communications in Theoretical Physics》 2025年第6期1-20,共20页
The present work primarily aims to explore the neuronal calcium(Ca^(2+)),IP_(3),and dopamine(DA)signaling systems through a feedback loop model.To date,there has been no exploration of this feedback model in fractiona... The present work primarily aims to explore the neuronal calcium(Ca^(2+)),IP_(3),and dopamine(DA)signaling systems through a feedback loop model.To date,there has been no exploration of this feedback model in fractional-order dynamical systems.This feedback loop model incorporates several crucial mechanisms like the buffering process,IP_(3)-receptor,ryanodine receptor,plasma membrane Ca^(2+)ATPase and sarcoplasmic/endoplasmic reticulum calcium ATPase(SERCA)pump,leak,sodium-calcium exchanger,voltage-gated Ca^(2+)channel,Orai channels,DA-dependent IP_(3)synthesis,and others.By incorporating these mechanisms,the model aims to provide a more comprehensive and realistic understanding of the system under investigation.The present model incorporates fractional-order dynamics along both spatial and temporal dimensions to examine the impacts of superdiffusion and memory showing Brownian motion of Ca^(2+),IP_(3),and DA signaling molecules.The bidirectional feedback between calcium and IP_(3)signaling systems,unidirectional feedback between calcium and dopamine signaling systems,and unidirectional feedback between IP_(3)and dopamine signaling systems have been incorporated into the present model.These feedback loops establish interactions among calcium,IP_(3),and dopamine signaling systems within neuronal cells.The numerical findings were obtained by using the Crank-Nicholson method with the Grunwald technique for fractional space derivatives and the L1method for fractional time derivatives in conjunction with the Gauss-Seidel Iterations.This research specifically investigates the implications of cell memory as well as superdiffusion on Ca^(2+),IP_(3),and DA dynamics in neuronal cells,which are interactive nonlinear systems.The superdiffusion process results in a reduction in Ca^(2+),IP_(3),and DA concentrations,while cellular memory leads to an increase in ion and molecule concentrations in neuronal cells during the initial time.The disruption of any given process can lead to imbalances in calcium,IP_(3),and DA systems,hence contributing to neurotoxicity and cellular demise. 展开更多
关键词 feedback loop among Ca^(2+) IP_(3)and dopamine systems reaction-diffusion equations fractional-order dynamics SUPERDIFFUSION cell memory
原文传递
Endobutton带袢钛板与螺钉固定治疗下胫腓联合韧带损伤的疗效比较
7
作者 王琼超 陈宏峰 +3 位作者 姚佳乐 李真 李晓奇 陈贝贝 《中国疗养医学》 2026年第2期104-108,共5页
目的对比Endobutton带袢钛板与下胫腓螺钉治疗踝关节骨折合并下胫腓联合韧带损伤的临床疗效。方法选取漯河医学高等专科学校第二附属医院足踝外科2022年1月至2024年6月收治的踝关节骨折合并下胫腓联合韧带损伤的手术患者48例为本次研究... 目的对比Endobutton带袢钛板与下胫腓螺钉治疗踝关节骨折合并下胫腓联合韧带损伤的临床疗效。方法选取漯河医学高等专科学校第二附属医院足踝外科2022年1月至2024年6月收治的踝关节骨折合并下胫腓联合韧带损伤的手术患者48例为本次研究对象,根据手术固定方式不同分为Endobutton带袢钛板(弹性组)24例和下胫腓螺钉(硬性组)24例。比较两组患者手术情况、负重时间、并发症发生率:感染、皮肤坏死、骨折延迟愈合、固定失败等,术前及术后1个月、3个月、6个月、12个月胫腓联合间隙(TBCS)、胫腓骨重叠(TOL)情况,术后1个月、2个月、3个月、6个月、12个月根据美国足踝外科协会(AOFAS)踝-后足评分量表评价临床疗效。结果与硬性组相比,弹性组手术时间更长、出血量增加、部分负重时间和完全负重时间缩短,两组数据比较差异有统计学意义(P<0.05)。术后两组TBCS小于术前(P<0.05),TOL大于术前(P<0.05),两组比较差异无统计学意义(P>0.05)。弹性组术后1个月、2个月及3个月AOFAS评分相比硬性组差异有统计学意义(P<0.05),弹性组术后6个月及12个月AOFAS评分与硬性组相比差异无统计学意义(P>0.05),弹性组并发症总发生率4.17%(1/24)低于硬性组8.33%(2/24),差异无统计学意义(P>0.05)。结论踝关节骨折合并下胫腓联合韧带损伤的患者采用下胫腓螺钉坚强固定与Endobutton带袢钛板弹性固定均能获得较好的术后临床效果,但Endobutton带袢钛板弹性固定更符合生物力学特性,减少住院次数,缩短患病周期、改善早期AOFAS功能评分,康复锻炼更早。 展开更多
关键词 Endobutton带袢钢板 螺钉固定 下胫腓联合韧带 踝关节骨折 疗效
暂未订购
依赖于c-Myc的R-loops结构对胶质瘤细胞增殖、侵袭和迁移的调控作用
8
作者 林家汉 陈彩燕 +2 位作者 陈申波 叶富跃 杨堃 《中华神经外科疾病研究杂志》 2026年第2期16-22,共7页
目的探讨转录因子c-Myc的R-loops结构及其对胶质瘤细胞恶性生物学行为的调控作用。方法采用DNA-RNA免疫沉淀PCR(DNA-RNA immunoprecipitation PCR,DRIP-PCR)法检测胶质瘤细胞(U251和U87-MG)中c-Myc的R-loops结构。分别将空载质粒、c-My... 目的探讨转录因子c-Myc的R-loops结构及其对胶质瘤细胞恶性生物学行为的调控作用。方法采用DNA-RNA免疫沉淀PCR(DNA-RNA immunoprecipitation PCR,DRIP-PCR)法检测胶质瘤细胞(U251和U87-MG)中c-Myc的R-loops结构。分别将空载质粒、c-Myc过表达质粒、RNASEH1过表达质粒转染至U251和U87-MG细胞,设立对照组(CTRL组)、核糖核酸内切酶H1(RNASEH1)过表达组(RNASEH1-OE组)、c-Myc过表达组(c-Myc-OE组)及共转染c-Myc与RNASEH1共转染组(c-Myc-OE+RNASEH1-OE组)。采用细胞计数试剂盒-8(CCK-8)、5-乙炔基-2'-脱氧尿苷(EdU)实验检测细胞增殖能力;通过细胞划痕实验和Transwell实验评估细胞迁移和侵袭水平;利用蛋白印迹法(Western blot)检测RNASEH1和c-Myc的蛋白表达水平。结果转录因子c-Myc在胶质瘤细胞中存在R-loops结构(P<0.05)。过表达RNASEH1可清除c-Myc依赖的R-loops结构,从而抑制胶质瘤细胞的增殖、侵袭和迁移(P<0.05)。c-Myc的过表达可提高核糖核酸内切酶H1(RNASEH1)的表达,从而挽救其R-loops结构,促进胶质瘤细胞侵袭和迁移能力的影响(P<0.05)。结论转录因子c-Myc可能通过其R-loops结构促进胶质瘤细胞的增殖、侵袭和迁移等恶性生物学行为。 展开更多
关键词 C-MYC 核糖核酸内切酶H1 R环 胶质瘤 增殖 侵袭 迁移
暂未订购
Performance analysis of a novel chip tracking loop used for regenerative pseudo-noise ranging clock recovery
9
作者 张朝杰 金小军 +1 位作者 郁发新 金仲和 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期185-189,共5页
To improve the performance of composite pseudo-noise (PN) code clock recovery in a regenerative PN ranging system at a low symbol signal-to-noise ratio (SNR), a novel chip tracking loop (CTL) used for regenerati... To improve the performance of composite pseudo-noise (PN) code clock recovery in a regenerative PN ranging system at a low symbol signal-to-noise ratio (SNR), a novel chip tracking loop (CTL) used for regenerative PN ranging clock recovery is adopted. The CTL is a modified data transition tracking loop (DTTL). The difference between them is that the Q channel output of the CTL is directly multiplied by a clock component, while that of the DTTL is multiplied by the Ⅰ channel transition detector output. Under the condition of a quasi-squareware PN ranging code, the tracking ( mean square timing jitter) performance of the CTL is analyzed. The tracking performances of the CTL and the DTTL, are compared over a wide range of symbol SNRs. The result shows that the CTL and the DTTL have the same performance at a large symbol SNR, while at a low symbol SNR, the former offers a noticeable enhancement. 展开更多
关键词 clock recovery tracking loops pseudo-noise codes ranging data transition tracking loop chip tracking loop
在线阅读 下载PDF
EFFECTIVE DOUBLE LOOP CONTROL FOR A SQUARE WAVE BRUSHLESS DC MOTOR
10
作者 周波 李先祥 朱震莲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期34+30-33,共5页
A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yie... A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yields a combination of desired characteristics including simplified control structure, small ripple torque, high speed accuracy, wide operating speed range, and fast dynamic response. Experimental results confirm excellent characteristics of the motor. 展开更多
关键词 synchronous motors speed control systems INVERTERS brushless DC motor double loop control square wave motors
在线阅读 下载PDF
浅谈DO…Loop不同循环结构语句间的区别
11
作者 耿梅英 《太原城市职业技术学院学报》 2010年第9期159-160,共2页
Visual Basic程序设计教程(简称VB)是目前应用最广泛的、易学易用的、面向对象的开发工具之一,是大中专院校计算机基础课程普遍采用的教材。Do…Loop循环结构语句是VB课程中最通用的、最有用的一种循环结构,是用来描述有规律地重复执行... Visual Basic程序设计教程(简称VB)是目前应用最广泛的、易学易用的、面向对象的开发工具之一,是大中专院校计算机基础课程普遍采用的教材。Do…Loop循环结构语句是VB课程中最通用的、最有用的一种循环结构,是用来描述有规律地重复执行某一程序段,其作用是简化程序的设计,提高编程效率。笔者在教学过程中发现很多初学者搞不清DO…Loop不同循环结构语句间的区别,这在一定程度上影响了学生的编程兴趣。 展开更多
关键词 VISUAL BASIC程序设计 doloop循环结构语句 程序流程图
在线阅读 下载PDF
Bcl-2 loop domain在Bcl-2蛋白结构中的作用初探
12
作者 刘娜 孙志扬 +2 位作者 李杨 宋海燕 孙庆文 《复旦学报(医学版)》 CAS CSCD 北大核心 2006年第5期671-674,共4页
目的探讨B细胞淋巴瘤/白血病基因2(Bcl-2)Loop domain结构域在Bcl-2蛋白结构中的作用。方法应用PCR及Western blot方法检测Bcl-2 Loop domain结构域突变前后Bcl-2蛋白的表达情况。结果Bcl-2 Loop domain结构域突变后Bcl-2蛋白只在沉淀... 目的探讨B细胞淋巴瘤/白血病基因2(Bcl-2)Loop domain结构域在Bcl-2蛋白结构中的作用。方法应用PCR及Western blot方法检测Bcl-2 Loop domain结构域突变前后Bcl-2蛋白的表达情况。结果Bcl-2 Loop domain结构域突变后Bcl-2蛋白只在沉淀中检测到,在上清中未检测到。结论Bcl-2 Loop domain结构域被突变后,Bcl-2蛋白空间结构发生改变,推测Bcl-2 Loop domain结构域在Bcl-2蛋白结构中起到重要作用。 展开更多
关键词 B细胞淋巴瘤/白血病基因2 环状结构域 基因突变
暂未订购
Visual FoxPro中DO WHILE循环语句的灵活使用
13
作者 尹树玲 《重庆工学院学报》 2007年第23期140-143,共4页
针对初学者在循环结构程序设计中存在的问题,分析了DO WHILE循环语句与FOR语句及SCAN语句的区别,举例说明了DO WHILE循环语句的灵活使用方法.
关键词 循环结构 循环条件 循环体
在线阅读 下载PDF
A systematic review of clinical practice guidelines and best practice statements for the diagnosis and management of varicocele in children and adolescents 被引量:9
14
作者 Matheus Roque Sandro C Esteves 《Asian Journal of Andrology》 SCIE CAS CSCD 2016年第2期262-268,J0006,共8页
A systematic review was conducted to identify and qualitatively analyze the methods as well as recommendations of Clinical Practice Guidelines (CPG) and Best Practice Statements (BPS) concerning varicocele in the ... A systematic review was conducted to identify and qualitatively analyze the methods as well as recommendations of Clinical Practice Guidelines (CPG) and Best Practice Statements (BPS) concerning varicocele in the pediatric and adolescent population. An electronic search was performed with the MEDLINE, EMBASE, Science Direct, and Scielo databases, as well as guidelines' Web sites until September 2015. Four guidelines were included in the qualitative synthesis. In general, the recommendations provided by the CPG/BPS were consistent despite the existence of some gaps across the studies. The guidelines issued by the American Urological Association (AUA) and American Society for Reproductive Medicine (ASRM) did not provide evidence-based levels for the recommendations given. Most of the recommendations given by the European Association of Urology (EAU) and European Society of Pediatric Urology (ESPU) were derived from nonrandomized clinical trials, retrospective studies, and expert opinion. Among all CPG/BPS, only one was specifically designed for the pediatric population. The studied guidelines did not undertake independent cost-effectiveness and risk-benefit analysis. The main objectives of these guidelines were to translate the best evidence into practice and provide a framework of standardized care while maintaining clinical autonomy and physician judgment. However, the limitations identified in the CPG/BPS for the diagnosis and management of varicocele in children and adolescents indicate ample opportunities for research and future incorporation of higher quality standards in patient care. 展开更多
关键词 AdoLESCENT best practice statements CHILD clinical practice guidelines varicocele systematic review
原文传递
Application of internal fixation of steel-wire limited loop in early Achilles tendon rupture 被引量:10
15
作者 Zhe Chen Jia-Sen Wei +3 位作者 Zhao-Yang Hou Jiong Hu Yan-Guang Cao Qi-Xin Chen 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第11期902-907,共6页
Objective:To explore the clinical effect and safety of internal fixation of steel-wire limited loop in early Achilles tendon rupture.Methods:Seventy-six patients respectively with early transected and avulsed types of... Objective:To explore the clinical effect and safety of internal fixation of steel-wire limited loop in early Achilles tendon rupture.Methods:Seventy-six patients respectively with early transected and avulsed types of Achilles tendon rupture were selected and treated with internal fixation of steel-wire limited loop.The patients began to take exercise for their lower limbs through continous passive motion as early as possible after surgical repair,and the loops were removed after 3-5 months.Six months later,the condition of complications including Achilles tendon re-rupture,wound fistula,wound infection and skin necrosis,cutaneous sensation in sural nerve dominance region,time back to preinjury work or learning as well as time to physical activities were observed.One year later,the therapeutic effect was evaluated,and the maximum circumferences of bilateral legs and raptured plane circumferences of Achilles tendon were measured.Results:The wound of all patients healed well,no complications like Achilles tendon re-rupture,wound fistula,wound infection and skin necrosis occured,and the cutaneous sensation in sural nerve dominance region was normal.The mean time back to preinjury work or learning as well as to pysical activities of all patients were respectively 10 and 22 weeks.Seventy out of 76 patients(92.1%) achieved an excellent effect,and 6(7.9%) good effect.The excellent and good rate came up to 100%.The maximum circumference in the affected leg decreased to 2 mm averagely compared with the offside,while the ruptured plane circumferences of Achilles tendon in the affected side increased to 2.2 mm compared with the offside.Conclusions:Kor early Achilles tendon rupture,internal fixation of steel-wire limited loop can recover the ankle function better,return to the preinjury state in the shortest lime,and has few complications. 展开更多
关键词 ACHILLES TENdoN rupture Steel-wire LIMITED loop Internal fixation ANKLE function
暂未订购
Endobutton带袢钢板弹性固定治疗下胫腓联合损伤的临床研究 被引量:1
16
作者 王世辉 陈颖 +2 位作者 张宁 刘增兵 王金广 《临床外科杂志》 2025年第2期162-165,共4页
目的 探讨使用Endobutton带袢钢板进行弹性固定在下胫腓联合损伤治疗中的临床效果。方法 2019年6月~2021年6月行手术治疗的下胫腓联合损伤合并踝关节骨折病人326例,采用随机数字表将病人随机分为试验组(163例)和对照组(163例)。对照组... 目的 探讨使用Endobutton带袢钢板进行弹性固定在下胫腓联合损伤治疗中的临床效果。方法 2019年6月~2021年6月行手术治疗的下胫腓联合损伤合并踝关节骨折病人326例,采用随机数字表将病人随机分为试验组(163例)和对照组(163例)。对照组行传统钢板螺钉固定,试验组行Endobutton带袢钢板弹性固定。比较两组病人住院和手术相关指标。分别在术后2个月、6个月对两组病人进行美国足踝外科协会踝关节功能评分(AOFAS),并在术后6个月评估比较两组病人下胫腓联合再次分离率。结果 试验组与对照组病人手术时间、出血量、切口长度、下床活动时间及住院时间比较差异均无统计学意义(P>0.05)。试验组术后并发症发生率为2.45%,低于对照组的7.98%,两组比较差异有统计学意义(P<0.05)。对照组病人术后2个月、6个月AOFAS分别为(74.5±9.2)分、(81.3±4.3)分,优良率为76.0%;试验组病人术后2个月、6个月AOFAS分别为(82.3±5.3)分、(91.2±3.8)分,优良率为93.2%,试验组上述指标均高于对照组,两组比较差异有统计学意义(P<0.05)。术后6个月复查对照组下胫腓联合再次分离率为12.8%,试验组为2.4%,试验组再次分离风险低于对照组,两组比较差异有统计学意义(P<0.05)。结论 Endobutton带袢钢板弹性固定可用于踝关节骨折合并下胫腓联合损伤,效果优于传统钢板螺钉内固定。 展开更多
关键词 下胫腓联合损伤 Endobutton带袢钢板 弹性固定
暂未订购
Management of afferent loop obstruction: Reoperation or endoscopic and percutaneous interventions? 被引量:8
17
作者 Konstantinos Blouhos Konstantinos Andreas Boulas +1 位作者 Konstantinos Tsalis Anestis Hatzigeorgiadis 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2015年第9期190-195,共6页
Afferent loop obstruction is a purely mechanical complication that infrequently occurs following construction of a gastrojejunostomy. The operations most commonly associated with this complication are gastrectomy with... Afferent loop obstruction is a purely mechanical complication that infrequently occurs following construction of a gastrojejunostomy. The operations most commonly associated with this complication are gastrectomy with Billroth Ⅱ or Roux-en-Y reconstruction, and pancreaticoduodenectomy with conventional loop or Roux-en-Y reconstruction. Etiology of afferent loop obstruction includes:(1) entrapment, compression and kinking by postoperative adhesions;(2) internal herniation, volvulus and intussusception;(3) stenosis due to ulceration at the gastrojejunostomy site and radiation enteritis of the afferent loop;(4) cancer recurrence; and(5) enteroliths, bezoars and foreign bodies. Acute afferent loop obstruction is associated with complete obstruction of the afferent loop and represents a surgical emergency, whereas chronic afferent loop obstruction is associated with partial obstruction. Abdominal multiple detector computed tomography is the diagnostic study of choice. CT appearance of the obstructed afferent loop consists of a C-shaped, fluidfilled tubular mass located in the midline between the abdominal aorta and the superior mesenteric artery with valvulae conniventes projecting into the lumen. The cornerstone of treatment is surgery. Surgery includes:(1) adhesiolysis and reconstruction for benign causes; and(2) by-pass or excision and reconstruction for malignant causes. However, endoscopic enteral stenting, transhepatic percutaneous enteral stenting and direct percutaneous tube enterostomy have the principal role in management of malignant and radiation-induced obstruction. Nevertheless, considerable limitations exist as a former Roux-en-Y reconstruction limits endoscopic access to the afferent loop and percutaneous approaches for enteral stenting and tube enterostomy have only been reported in the literature as isolated cases. 展开更多
关键词 AFFERENT loop OBSTRUCTION REOPERATION ENdoSCOPY En
暂未订购
Endoscopic treatment of efferent loop syndrome with insertion of double pigtail stent 被引量:4
18
作者 Woo Yong Lee Jeong Seop Moon 《World Journal of Gastroenterology》 SCIE CAS 2013年第41期7209-7212,共4页
Efferent loop syndrome is a very rare postgastrectomy syndrome that can occur following Billroth-Ⅱor Rouxen-Y reconstruction.The most common loop syndrome after gastric surgery is afferent loop syndrome;however,effer... Efferent loop syndrome is a very rare postgastrectomy syndrome that can occur following Billroth-Ⅱor Rouxen-Y reconstruction.The most common loop syndrome after gastric surgery is afferent loop syndrome;however,efferent loop syndrome has been reported in rare cases.Here,we report a case of efferent loop obstruction that occurred after postoperative adhesiolysis of a small-bowel obstruction.The patient had undergone a partial gastrectomy with BillrothⅡanastomosis and gastric ulcer perforation 30 years prior.The efferent loop obstruction was successfully resolved by the insertion of a double pigtail stent.To the best of our knowledge,this is the first case in the literature describing the treatment of efferent loop obstruction. 展开更多
关键词 Efferent loop SYNDROME doUBLE PIGTAIL STENT Postgastrectomy SYNDROME
暂未订购
Different oxidation routes for lattice oxygen recovery of double-perovskite type oxides LaSrFeCoO6 as oxygen carriers for chemical looping steam methane reforming 被引量:3
19
作者 Kun Zhao Yang Shen +5 位作者 Zhen Huang Fang He Guoqiang Wei Anqing Zheng Haibin Li Zengli Zhao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第3期501-509,共9页
Double-perovskite type oxide LaSrFeCoO(LSFCO) was used as oxygen carrier for chemical looping steam methane reforming(CL-SMR) due to its unique structure and reactivity. Two different oxidation routes,steam-oxidat... Double-perovskite type oxide LaSrFeCoO(LSFCO) was used as oxygen carrier for chemical looping steam methane reforming(CL-SMR) due to its unique structure and reactivity. Two different oxidation routes,steam-oxidation and steam-air-stepwise-oxidation, were applied to investigate the recovery behaviors of the lattice oxygen in the oxygen carrier. The characterizations of the oxide were determined by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS), hydrogen temperature-programmed reduction(H-TPR) and scanning electron microscopy(SEM). The fresh sample LSFCO exhibits a monocrystalline perovskite structure with cubic symmetry and high crystallinity, except for a little impurity phase due to the antisite defect of Fe/Co disorder. The deconvolution distribution of XPS patterns indicated that Co,and Fe are predominantly in an oxidized state(Feand Fe) and(Coand Co), while O 1s exists at three species of lattice oxygen, chemisorbed oxygen and physical adsorbed oxygen. The double perovskite structure and chemical composition recover to the original state after the steam and air oxidation, while the Co ion cannot incorporate into the double perovskite structure and thus form the CoO just via individual steam oxidation. In comparison to the two different oxidation routes, the sample obtained by steam-oxidation exhibits even higher CHconversion, CO and Hselectivity and stronger hydrogen generation capacity. 展开更多
关键词 doUBLE-PEROVSKITE Chemical looping Lattice oxygen Oxidizing agent Redox
在线阅读 下载PDF
Dopamine D4 Receptor Gene Associated with the Frontal-Striatal-Cerebellar Loop in Children with ADHD: A Resting-State fMRI Study 被引量:12
20
作者 ANDan Qian Xin Wang +8 位作者 Huiru Liu Jiejie Tao Jiejie Zhou Qiong Ye Jiance Li Chuang Yang Jingliang Cheng Ke Zhao Meihao Wang 《Neuroscience Bulletin》 SCIE CAS CSCD 2018年第3期497-506,共10页
Attention deficit hyperactivity disorder(ADHD)is a common childhood neuropsychiatric disorder that has been linked to the dopaminergic system. This study aimed to investigate the effects of regulation of the dopamin... Attention deficit hyperactivity disorder(ADHD)is a common childhood neuropsychiatric disorder that has been linked to the dopaminergic system. This study aimed to investigate the effects of regulation of the dopamine D4 receptor(DRD4) on functional brain activity during the resting state in ADHD children using the methods of regional homogeneity(Re Ho) and functional connectivity(FC). Resting-state functional magnetic resonance imaging data were analyzed in 49 children with ADHD. All participants were classified as either carriers of the DRD44-repeat/4-repeat(4 R/4 R) allele(n = 30) or the DRD42-repeat(2 R) allele(n = 19). The results showed that participants with the DRD4 2 R allele had decreased Re Ho bilaterally in the posterior lobes of the cerebellum, while Re Ho was increased in the left angular gyrus. Compared with participants carrying the DRD4 4 R/4 R allele, those with the DRD4 2 R allele showed decreased FC to the left angular gyrus in the left striatum, right inferior frontal gyrus, and bilateral lobes of the cerebellum. The increased FC regions included the left superior frontal gyrus, medial frontal gyrus, and rectus gyrus. These data suggest that the DRD4 polymorphisms are associated with localized brain activity and specific functional connections, including abnormality in the frontal-striatal-cerebellar loop. Our study not only enhances the understanding of the correlation between the cerebellar lobes and ADHD, but also provides an imaging basis for explaining the neural mechanisms underlying ADHD in children. 展开更多
关键词 Attention deficit hyperactivity disorder dopamine D4 receptor Frontal-striatal-cerebellar loop Resting-state functional magnetic resonance imaging Regional homogeneity Functional connectivity
原文传递
上一页 1 2 250 下一页 到第
使用帮助 返回顶部