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J波时限与夹角在急性心肌梗死中的临床观察
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作者 范文茂 徐新 +5 位作者 张社兵 唐良秋 陈宝峰 陈锦峰 胡秀莲 班秀芬 《心电图杂志(电子版)》 2018年第2期143-145,共3页
目的探讨在急性心肌梗死中J波以及J波时限与夹角与心律失常关系。方法对我院住院治疗的356例急性ST段抬高心肌梗死患者进行分析,观察缺血性J波,J波时限及夹角与室性心律失常、患者住院期间死亡率等指标。结果伴有J波的急性心梗患者室性... 目的探讨在急性心肌梗死中J波以及J波时限与夹角与心律失常关系。方法对我院住院治疗的356例急性ST段抬高心肌梗死患者进行分析,观察缺血性J波,J波时限及夹角与室性心律失常、患者住院期间死亡率等指标。结果伴有J波的急性心梗患者室性心律失常发生率明显高于不伴有缺血性J波患者;J波时限及或J波夹角阳性患者发生室性心律失常发生率明显高于J波时限及或J波夹角阴性患者;急性心肌梗死合并J波患者近期死亡率明显高于不伴J波急性心梗患者。结论急性心肌梗死患者合并缺血性J波,尤其J波时限长及夹角增大的患者室性心律失常发生率高且死亡率高。 展开更多
关键词 急性心肌梗死 J波 时限 夹角 室性心律失常
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Sex But Not Altitude, Modulates Phenotypic Covariations Between Growth and Physiological Traits in Adult Asiatic Toads
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作者 Ping LI Song TAN +3 位作者 Zhongyi YAO Gaohui LIU Jinzhong FU jingfeng chen 《Asian Herpetological Research》 SCIE CSCD 2022年第1期34-42,共9页
The pace-of-life syndrome(POLS) hypothesis predicts that most variation in life history, physiology,and behavior among individuals, popula tions, and species falls along a continuum from slow to fast pace of life. Whi... The pace-of-life syndrome(POLS) hypothesis predicts that most variation in life history, physiology,and behavior among individuals, popula tions, and species falls along a continuum from slow to fast pace of life. While there is evidence for climatic gradientmediated POLS patterns among species, this approach has rarely been explicitly used to study POLS patterns among-and within-populations. In addition, the roles of sex in POLS evolution among-or within-populations are largely unknown. In this study, we investigated the effects of altitudinal gradient and sex on the covariations between growth rate and several physiological traits closely associated with POLS(blood glucose, baselineand stress-induced glucocorticoids(GCs), hemolysis and hemagglutination) in the Asiatic toad Bufo gargarizans.Contrary to our expectation, altitudinal gradient had no influence on the covariations between growth rate and physiological traits, neither at the among-nor withinpopulation level, indicating that these trait integrations have similar fitness payoffs across hierarchical levels.In contrast, we found evidence for sex-specific POLS composition: there was a negative covariance structure between growth rate and baseline GCs-but only in females, and a positive covariance structure between growth rate and baseline GCs-but only in females, and a positive covariance structure between growth rate and hemagglutination-but only in males. This observation indicates that these trait associations differ dramatically in advancing fitness for each sex, and supports the idea that sex-specific POLS composition could evolve in species in which the reproductive roles largely differ between the sexes. 展开更多
关键词 Bufo gargarizans constraint GLUCOCORTICOIDS immunity metabolism phenotypic integration physiological pace-of-life syndrome
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Effects of Dietary Protein Variations at Different Life-stages on Vocal Dominance of the African Clawed Frogs
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作者 Yan CAO Jiangyan SHEN +5 位作者 Xiaocui WANG Song TAN Ping LI Jianghong RAN Yezhong TANG jingfeng chen 《Asian Herpetological Research》 SCIE CSCD 2020年第3期249-256,共8页
How nutritional conditions during early development affect an organism’s phenotype at adulthood is still poorly understood despite a plethora of research on developmental plasticity.The"environmental matching&qu... How nutritional conditions during early development affect an organism’s phenotype at adulthood is still poorly understood despite a plethora of research on developmental plasticity.The"environmental matching"hypothesis predicts that individuals will have high fitness providing that their adult environment"matches"what they experienced during development.In contrast,the"silver spoon"hypothesis predicts that individuals who obtain better developmental resources will be generally superior.Here we tested these two hypotheses and examined the underlying hormonal mechanisms by manipulating the early dietary protein content of African clawed frogs(Xenopus laevis)for a year with a 2×2 factorial experimental design.We found that only a lowprotein food during development enhanced the vocal competition ability of male X.laevis,and that vocal dominance was associated with higher cortisol levels but not related with testosterone content.These results were not congruent with the"environmental matching"hypothesis or with the"silver spoon"hypothesis,suggesting the behavioral plasticity during development is more complex than our expectation in amphibians. 展开更多
关键词 AGGRESSION developmental effects environmentalmatching silver spoon social status vocal competition Xenopus laevis
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Big Data Analytics in Healthcare: Data-Driven Methods for Typical Treatment Pattern Mining 被引量:3
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作者 Chonghui Guo jingfeng chen 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2019年第6期694-714,共21页
A huge volume of digitized clinical data is generated and accumulated rapidly since the widespread adoption of Electronic Medical Records (EMRs).These big data in healthcare hold the promise of propelling healthcare e... A huge volume of digitized clinical data is generated and accumulated rapidly since the widespread adoption of Electronic Medical Records (EMRs).These big data in healthcare hold the promise of propelling healthcare evolving from a proficiency-based art to a data-driven science,from a reactive mode to a proactive mode,from one-size-fits-all medicine to personalized medicine.This paper first discusses the research background-big data analytics in healthcare,the research framework of big data analytics in healthcare,analysis of medical process,and the literature summary of treatment pattern mining.Then the challenges for data-driven typical treatment pattern mining are highlighted,including similarity measure between treatment records,typical treatment pattern extraction,evaluation and recommendation,when considering the rich temporal and heterogeneous medical information in EMRs.Furthermore,three categories of typical treatment patterns are mined from doctor order content,duration,and sequence view respectively,which can provide a data-driven guideline to achieve the "5R" goal for rational drug use and clinical pathways. 展开更多
关键词 BIG data ANALYTICS healthcare electronic MEDICAL RECORDS TYPICAL TREATMENT pattern
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Mining Typical Treatment Duration Patterns for Rational Drug Use from Electronic Medical Records 被引量:2
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作者 jingfeng chen Chonghui Guo +1 位作者 Leilei Sun Menglin Lu 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2019年第5期602-620,共19页
Rational drug use requires that patients receive medications for an adequate period of time.The adequate duration time of medications not only improve the therapeutic effect of medicines,but also reduce the side effec... Rational drug use requires that patients receive medications for an adequate period of time.The adequate duration time of medications not only improve the therapeutic effect of medicines,but also reduce the side effects and adverse reactions of medicines.This paper proposes a data-driven method to mine typical treatment duration patterns for rational drug use from electronic medical records (EMRs).Firstly,a quintuple is defined to describe drug use duration statistics (DUDS) for each drug and treatment record is further represented with DUDS vector (DUDSV).Next a similarity measure method is adopted to compute the similarity between treatment records.Meanwhile,a clustering algorithm is used to cluster all patient treatment records to extract typical treatment duration patterns including typical drug sets,effective drug use day sets,and the DUDSs of each typical drug.Then the extracted typical treatment duration patterns are evaluated and annotated based on patients' demographic information,disease severity scores,treatment outcome and diagnostic information.Finally,a real-world EMR dataset is performed to indicate that the approach we proposed can effectively mine typical treatment duration patterns from EMRs and recommend the appropriate treatment regimens for patients based on their admission information. 展开更多
关键词 EMR data MINING RATIONAL drug use TYPICAL treatment DURATION pattern SIMILARITY measure clustering
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Direction Finding with Cyclostationarity Analysis Against Frequency Interference
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作者 Han Liu jingfeng chen +3 位作者 Ziheng Ding Gang Ni Chong He Ronghong Jin 《Journal of Communications and Information Networks》 EI CSCD 2022年第1期88-95,共8页
In this paper, a novel anti-interference direction finding(DF)method for amplitude comparison method based on cyclostationarity is proposed. With the periodic properties of the communication signals, the desired signa... In this paper, a novel anti-interference direction finding(DF)method for amplitude comparison method based on cyclostationarity is proposed. With the periodic properties of the communication signals, the desired signal’s amplitude value can be effectively obtained even though there is an interference signal whose frequency spectrum overlaps with the desired signal in the environment,and the corresponding incident angle can be estimated accurately with the amplitude comparison method. The influence of interference signal on the amplitude comparison method is discussed and the proposed method’s theoretical feasibility is also analyzed. Compared with the conventional method,simulations are provided to demonstrate the anti-interference capability of the proposed method. The amplitude comparison DF system working at 2.44 GHz and 5.8 GHz is also constructed to verify its feasibility. 展开更多
关键词 CYCLOSTATIONARITY cyclic autocorrelation function(CAF) amplitude comparison method direction finding(DF)
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Time-Modulated Arrays:A Four-Dimensional Antenna Array Controlled by Switches
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作者 Chong He Lele Wang +1 位作者 jingfeng chen Ronghong Jin 《Journal of Communications and Information Networks》 2018年第1期1-14,共14页
With the rapid development of modern electronic technologies,antenna arrays typically operate in very complex electromagnetic environments.However,owing to the various errors such as systematic errors and random error... With the rapid development of modern electronic technologies,antenna arrays typically operate in very complex electromagnetic environments.However,owing to the various errors such as systematic errors and random errors,conventional antenna arrays have relatively high sidelobes.Time modulated arrays(TMAs),also known as four-dimensional(4-D)antenna arrays,introduce time as an additional dimension for generating ultra-low sidelobes at fundamental component and realizing real-time beam scanning by harmonic components.Recently,the harmonic components can also be developed for various new applications including wireless communications and radar systems.In this review,we introduce comprehensively the fundamental methodologies and recent applications of TMAs.This aims to stimulate continuing efforts for the understanding of TMAs and explore their applications in various aspects.The methods mentioned in this review include three aspects:sideband radiation suppression,power efficiency of TMAs,and applications of harmonic components.These methods either improve the existing TMAs or promote the practical applications of TMAs.First,to suppress the sideband radiation,a method using non-uniform periodical modulation is introduced.The proposed method has an advantage of low computation and can be easily used for synthesizing a real-time radiation pattern according to the environmental need.Next,a TMA structure using reconfigurable power dividers/combiner is introduced to improve the power efficiency of feeding network.Finally,three applications of harmonic component including direction finding,calibration method,and space division multiple access are separately introduced to illustrate the development potential of TMAs. 展开更多
关键词 TMAs sideband radiation suppression reconfigurable power dividers/combiner direction finding calibration method space division multiple access
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