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Existence of asymptotically almost periodic solutions and stability properties for functional difference equations 被引量:4
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作者 吴中华 《Journal of Chongqing University》 CAS 2012年第2期97-102,共6页
For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain li... For functional difference equations with unbounded delay,we characterized the existence of totally stable and asymptotically almost periodic solution by using stability properties of a bounded solution in a certain limiting equation. 展开更多
关键词 functional difference equations asymptotically almost periodic solutions total stability properties
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Properties for Solutions of Nonlinear Functional Difference Equations 被引量:2
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作者 DUANMU Lian-xi 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第3期258-264,共7页
In this paper, some sufficient and necessary conditions are established for the oscillatory of solutions for nonlinear functional difference equations, which extend and improve some corresponding results obtained and ... In this paper, some sufficient and necessary conditions are established for the oscillatory of solutions for nonlinear functional difference equations, which extend and improve some corresponding results obtained and are discrete analogues of the corresponding results for the continuous version. 展开更多
关键词 functional difference equation OSCILLATION increasing operator fixed point theorem
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Positive Solutions of p-Laplacian Functional Difference Equations 被引量:1
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作者 SONG Chang-xiu 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第4期475-481,共7页
In this paper, the author studies the boundary value problems for a p-Laplacian functional difference equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of the p... In this paper, the author studies the boundary value problems for a p-Laplacian functional difference equation. By using a fixed point theorem in cones, sufficient conditions are established for the existence of the positive solutions. 展开更多
关键词 p-Laplacian operator functional difference equations positive solution CONE
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Existence of Three Positive Periodic Solutions of Neutral Nonlinear Functional Difference Equations 被引量:1
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作者 LIU Xing-yuan 《Chinese Quarterly Journal of Mathematics》 2015年第2期172-183,共12页
This paper is concerned with the nonlinear neutral functional difference equations△x(n) =-a(n)x(n) +h(n)f(n,x(n-T(n)),△x(n-δ(n))),where a,h and f are nonnegative sequences.Sufficient conditions for the existence of... This paper is concerned with the nonlinear neutral functional difference equations△x(n) =-a(n)x(n) +h(n)f(n,x(n-T(n)),△x(n-δ(n))),where a,h and f are nonnegative sequences.Sufficient conditions for the existence of at least three positive T-periodic solutions are established by using a fixed point theorem due to Avery and Peterson. 展开更多
关键词 positive periodic solution functional difference equation fixed-point theorem
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One-Signed Periodic Solutions of First-Order Functional Difference Equations with Parameter
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作者 Yanqiong LU Ruyun MA Bo LU 《Journal of Mathematical Research with Applications》 CSCD 2018年第4期384-392,共9页
In this paper,the authors obtain the existence of one-signed periodic solutions of the first-order functional difference equation ?u(n) = a(n)u(n)-λb(n)f(u(n-τ(n))),n ∈ Z by using global bifurcation ... In this paper,the authors obtain the existence of one-signed periodic solutions of the first-order functional difference equation ?u(n) = a(n)u(n)-λb(n)f(u(n-τ(n))),n ∈ Z by using global bifurcation techniques,where a,b:Z → [0,∞) are T-periodic functions with ∑T n=1 a(n) 〉 0,∑T n=1 b(n) 〉 0;τ:Z → Z is T-periodic function,λ 〉 0 is a parameter;f ∈ C(R,R) and there exist two constants s2 〈 0 〈 s1 such that f(s2) = f(0) = f(s1) = 0,f(s) 〉 0 for s ∈(0,s1) ∪(s1,∞),and f(s) 〈 0 for s ∈(-∞,s2) ∪(s2,0). 展开更多
关键词 one-signed periodic solutions EXISTENCE functional difference equations bifurcationfrom infinity
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Existence of Periodic and Subharmonic Solutions for Second Order Functional Difference Equations
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作者 Hai-ping Shi Xue-jun Zhong 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2010年第2期229-240,共12页
In this paper, by using the critical point theory, the existence of periodic and subharmonic solutions to a class of second order functional difference equations is obtained. The main approach used in our paper is var... In this paper, by using the critical point theory, the existence of periodic and subharmonic solutions to a class of second order functional difference equations is obtained. The main approach used in our paper is variational technique and the Saddle Point Theorem. The problem is to solve the existence of periodic and subharmonic solutions of second order forward and backward difference equations. 展开更多
关键词 Periodic solutions subhaxmonic solutions functional difference equations saddle point theorem
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OPTIMAL EXISTENCE THEORY FOR SINGLE AND MULTIPLE POSITIVE PERIODIC SOLUTIONS TO FUNCTIONAL DIFFERENCE EQUATIONS WITH FEEDBACK CONTROL
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作者 Wang Yiqin Chen Xiaoxing (College of Math, and Computer Science, Fuzhou University, Fuzhou 350002) 《Annals of Differential Equations》 2006年第3期378-383,共6页
Using a fixed point theorem in a cone, we obtain some optimal existence results for single and multiple positive periodic solutions to a functional difference system with feedback control. Moreover, we apply our resul... Using a fixed point theorem in a cone, we obtain some optimal existence results for single and multiple positive periodic solutions to a functional difference system with feedback control. Moreover, we apply our results to a population model. 展开更多
关键词 functional difference system positive periodic solution fixed point theorem
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POSITIVE PERIODIC SOLUTIONS OF NONLINEAR FUNCTIONAL DIFFERENCE EQUATION
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作者 Qin Maochang Mei Fengxiang 《Annals of Differential Equations》 2006年第4期546-550,共5页
Using the Krasnoselskii's fixed point theorem, the existence of positive periodic solutions to a class of nonlinear functional difference equations is studied in this paper. Some sufficient conditions for the existen... Using the Krasnoselskii's fixed point theorem, the existence of positive periodic solutions to a class of nonlinear functional difference equations is studied in this paper. Some sufficient conditions for the existence of positive periodic solutions are presented. 展开更多
关键词 Krasnoselskii fixed point theorem positive periodic solution functional difference equation
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POSITIVE SOLUTIONS OF NONLINEAR FUNCTIONAL DIFFERENCE EQUATIONS
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作者 Ma Manjun Li Dong Li Xu 《Annals of Differential Equations》 2005年第4期580-586,共7页
In this paper we apply a cone theoretic fixed-point theorem proved by Krasnosel'skii to obtain sufficient conditions for the existence of positive solutions to some boundary value problems for a class of functional d... In this paper we apply a cone theoretic fixed-point theorem proved by Krasnosel'skii to obtain sufficient conditions for the existence of positive solutions to some boundary value problems for a class of functional difference equations. We consider the case that the nonlinear term satisfies asvrnntoticallv linear growth. 展开更多
关键词 functional difference equation nonlinear eigenvalue problem positive solutions fixed points
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Connectivity differences between adult male and female patients with attention deficit hyperactivity disorder according to resting-state functional MRI 被引量:7
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作者 Bo-yong Park Hyunjin Park 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第1期119-125,共7页
Attention deficit hyperactivity disorder(ADHD) is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have ex... Attention deficit hyperactivity disorder(ADHD) is a pervasive psychiatric disorder that affects both children and adults. Adult male and female patients with ADHD are differentially affected, but few studies have explored the differences. The purpose of this study was to quantify differences between adult male and female patients with ADHD based on neuroimaging and connectivity analysis. Resting-state functional magnetic resonance imaging scans were obtained and preprocessed in 82 patients. Group-wise differences between male and female patients were quantified using degree centrality for different brain regions. The medial-, middle-, and inferior-frontal gyrus, superior parietal lobule, precuneus, supramarginal gyrus, superior- and middle-temporal gyrus, middle occipital gyrus, and cuneus were identified as regions with significant group-wise differences. The identified regions were correlated with clinical scores reflecting depression and anxiety and significant correlations were found. Adult ADHD patients exhibit different levels of depression and anxiety depending on sex, and our study provides insight into how changes in brain circuitry might differentially impact male and female ADHD patients. 展开更多
关键词 neural regeneration connectivity attention deficit hyperactivity disorder sex difference functional magnetic resonance imaging depression anxiety network analysis degree centrality diagnostic and statistical manual score
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Early application of percutaneous neuromuscular electric stimulation in interfering motor function of limbs and difference in temperature of axilla of patients with ischemic stroke
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作者 Zhenhui Jiang Siyi Yin Na Bi Xiang He Fang Qu 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第2期188-189,共2页
BACKGROUND: Temperature of axilla could be affected due to motor dysfunction of limbs and neural changes of vessel after ischemic stroke. OBJECTIVE: To observe the effect of percutaneous neuromuscular electric stimu... BACKGROUND: Temperature of axilla could be affected due to motor dysfunction of limbs and neural changes of vessel after ischemic stroke. OBJECTIVE: To observe the effect of percutaneous neuromuscular electric stimulation (PNES) on difference in temperature of axilla and analyze the relationship between function of limbs and difference in temperature of axilla. DESIGN: Randomized grouping and controlled observation SETTING: Department of Neurology, General Hospital of Shenyang Military Area Command of Chinese PLA PARTICIPANTS: Sixty patients with ischemic stroke were selected from Neurological Department of General Hospital of Shenyang Military Area Command of Chinese PLA from January to June 2003. All cases were diagnosed with clinical diagnosis criteria of ischemic stroke established by the Fourth Chinese Classification of Cerebrovasular Disease and CT examination and received neuromuscular electric stimulation (NES). Patients were randomly divided into control group and treatment group with 30 in each group. METHODS: Control group: Patients received routinely neurological therapy. Treatment group: Except routine therapy, patients suffered from NES at 48 hours after hospitalization. NMT-91 NES equipment was used to stimulated injured limbs with low frequency once 30 minutes a day in total of 10 times a course, especially extensor muscle of upper limb and flexor muscle of lower limb. Prescription of hemiplegia was internally decided by equipment with the output frequency of 200 Hz. Intensity of electric output could cause muscle contraction. The therapy needed two or three courses. Temperature of bilateral axilla was measured every day to calculate the difference with the formula of (temperature of axilla on the injured side - temperature of axilla on the healthy side). Motor function of limbs was measured with FugI-Meyer Motor Assessment (FMA) during hospitalization and at 2 and 4 hours after hospitalization. Among 90 points, upper and lower limb function was 54, equilibrium function 10, sensory function 10, and motion of joint 16. The higher the scores were, the better the function was. Correlation of data was dealt with linear correlation analysis. MAIN OUTCOME MEASURES : Assessment and correlation between difference in temperature of axilla and motor function of injured limbs during hospitalization and at 2 and 4 weeks after hospitalization. RESULTS: All 60 patients with ischemic stroke were involved in the final analysis. ① Difference in temperature: Difference of 2 and 4 weeks after hospitalization was lower than that in control group and at just hospitalization [treatment group: (0.056±0.000), (0.024±0.003) ℃; control group: (0.250±0.001), (0.131 ±0.001)℃; hospitalization; (0.513±0.001) ℃, P 〈 0.05-0,01]. ② FMA scores: Scores of 2 and 4 weeks after hospitalization were higher than those in control group and at just hospitalization [treatment group; (43.50±15.09), (67.97 ±18.21) points; control group: (33.33 ±13.54), (40.87±19.34) points; hospitalization: (26.43 ±11.87) points, P 〈 0.05-0.01]. ③ Correlation: Difference in temperature of axilla was negative correlation with FMA scores (c=- -0.255 1, P 〈 0.05). CONCLUSION: ① PNES can accelerate recovery of limb function and decrease temperature of axilla of patients with ischemic stroke. ② The lower the difference in temperature is, the better the functional recovery is. 展开更多
关键词 lim Early application of percutaneous neuromuscular electric stimulation in interfering motor function of limbs and difference in temperature of axilla of patients with ischemic stroke
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Super-Hydrophilic/Aerophobic Co(OH)_(2)/NiFe Layered Double Hydroxide Heterostructures with Moderate Work Function Difference for Large-Current-Density Electrochemical Ammonia Synthesis
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作者 Yi Feng Jin-Tao Ren +5 位作者 Yue-Xin Song Wen-Wen Tian Hao-Yu Wang Lei Wang Ming-Lei Sun Zhong-Yong Yuan 《CCS Chemistry》 2025年第5期1344-1358,共15页
Developing NO_(2)−reduction reaction(NO_(2)−RR)and oxygen evolution reaction(OER)bifunctional electrocatalysts at large current densities is crucial for decreasing energy consumption of electrocatalytic NH3 production... Developing NO_(2)−reduction reaction(NO_(2)−RR)and oxygen evolution reaction(OER)bifunctional electrocatalysts at large current densities is crucial for decreasing energy consumption of electrocatalytic NH3 production and booming sustainable nitrogenbased economy.In addition to increasing active sites of catalysts,bubble adhesion deserves more attention during high-current electrolysis,which can deteriorate mass transfer and block active sites in gas-involving environments.Herein,super-hydrophilic/aerophobic cobalt-nickel-iron layered double hydroxide[Co(OH)_(2)/NiFe LDH]core-shell heterostructures were developed as efficient NO_(2)−RR and OER electrocatalysts to optimize surface tension due to self-pumping effect and modify active hydrogen adsorption behavior owing to moderate work function difference between Co(OH)_(2)and NiFe LDH.The fabricated Co(OH)_(2)/NiFe LDH exhibited excellent NO_(2)−RR activity(yield:50 mg h^(−1)cm^(−2);FE:91%at−500 mA cm^(−2))and impressive OER behavior(η1000:340 mV)accompanied by remarkable application potential for renewable energy-driven two-electrode system to produce NH3.This effort revealed important insights into the development of electrodes for reaching cost-effective electrocatalytic ammonia production at large current densities. 展开更多
关键词 heterostructure work function difference bifunctional electrocatalyst high current density mass transfer
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Analog parallel processor for broadband multifunctional integrated system based on silicon photonic platform
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作者 Na Qian Defu Zhou +5 位作者 Haowen Shu Ming Zhang Xingjun Wang Daoxin Dai Xiao Deng Weiwen Zou 《Light(Science & Applications)》 2025年第3期746-756,共11页
Sharing the hardware platform between diverse information systems to establish full cooperation among different functionalities has attracted substantial attention.However,broadband multifunctional integrated systems ... Sharing the hardware platform between diverse information systems to establish full cooperation among different functionalities has attracted substantial attention.However,broadband multifunctional integrated systems with large operating frequency ranges are challenging due to the bandwidth and computing speed restrictions of electronic circuitry.Here,we report an analog parallel processor(APP)based on the silicon photonic platform that directly discretizes and parallelizes the broadband signal in the analog domain.The APP first discretizes the signal with the optical frequency comb and then adopts optical dynamic phase interference to reassign the analog signal into 2N parallel sequences.Via photonic analog parallelism,data rate and data volume in each sequence are simultaneously compressed,which mitigates the requirement on each parallel computing core.Moreover,the fusion of the outputs from each computing core is equivalent to directly processing broadband signals.In the proof-of-concept experiment,two-channel analog parallel processing of broadband radar signals and high-speed communication signals is implemented on the single photonic integrated circuit.The bandwidth of broadband radar signal is 6 GHz and the range resolution of 2.69 cm is achieved.The wireless communication rate of 8 Gbit/s is also validated.Breaking the bandwidth and speed limitations of the single-computing core along with further exploring the multichannel potential of this architecture,we anticipate that the proposed APP will accelerate the development of powerful optoelectronic processors as critical support for applications such as satellite networks and intelligent driving. 展开更多
关键词 analog parallel processor sharing hardware platform multifunctional integrated systems establish full cooperation different functionalities analog parallel processor app based silicon photonic platform electronic circuitryherewe broadband signal
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Genome-wide identification and evolutionary analysis of MLO gene family in Rosaceae plants 被引量:2
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作者 Yongxian Tian Qigang Wang +7 位作者 Hao Zhang Ningning Zhou Huijun Yan Hongying Jian Shubin Li Guisheng Xiang Kaixue Tang Xianqin Qiu 《Horticultural Plant Journal》 SCIE CSCD 2022年第1期110-122,共13页
Mutants lacking wild-type MLO(Mildew resistance Locus O)proteins show broad-spectrum resistance to the powdery mildew fungus,and dysregulated cell death control,with spontaneous cell death in response to developmental... Mutants lacking wild-type MLO(Mildew resistance Locus O)proteins show broad-spectrum resistance to the powdery mildew fungus,and dysregulated cell death control,with spontaneous cell death in response to developmental or abiotic stimuli.In order to understand the evolution and divergence patterns of the MLO gene family in Rosaceae plants,we analysed systematically genome-wide data from Fragaria vesca,Prunus persica,Prunus mume,Malus domestica,Pyrus bretschneideri and Rubus occidentalis based on bioinformatics methods.Using three phylogenetic methods(the neighbour-joining,maximum likelihood,and Bayesian methods),we identified 117 MLO genes from 6 Rosaceae species.The results of all three phylogenetic analysis methods supported that these genes were divided into six clades.Conserved motif analysis found that only motif 2 was present in all MLO proteins and had 3 nearly invariant amino acid residues.The findings indicated that motif 2 might be shared by the MLO gene family.The structural features of these genes showed large variations in sequence length among different species,although the lengths and the numbers of exons exhibited high degrees of similarity.Selective pressure analysis showed extremely significant differences in all 6 clades,with 2,1,and 1 site(s)under significant positive selection detected in clades III,IV,and VI,respectively.These positive selection sites were important driving forces for the promotion of the functional differentiation of the MLO genes.Functional divergence analysis showed that the significantly divergent sites were located within the domains of the MLO genes.Functional distance analysis showed that the clade V had more conservative functions and might have retained more original functions during the evolutionary process.However,clade I may have undergone extensive altered functional constraints as a specialised functional role.Moreover,the most original function of the MLO genes in Rosaceae could be related to the evolution of their resistance to powdery mildew,which then gradually evolved into functions such as the regulation of flower development,the control of root morphology,and seed evolution due to the different evolutionary rates after gene duplication.These results provide a theoretical basis for further studies of the molecular evolutionary patterns of the plant MLO gene family. 展开更多
关键词 Rosaceae plants MLO gene Powdery mildew resistance Gene evolution Selective pressure functional difference
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Generalizations of mixed weighted power mean inequality 被引量:1
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作者 马统一 张海娟 《Journal of Shanghai University(English Edition)》 CAS 2006年第3期192-197,共6页
Tarnavas established mixed weighted power mean inequality in 1999. A separation of weighted power mean inequslity was derived in this paper. As its applications, some separations of other inequalities were given.
关键词 INEQUALITY power mean weighted power mean mixed weighted power mean difference function of mixed weightedpower mean separation
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Noether's theory of Lagrange systems in discrete case
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作者 吕洪升 张宏彬 顾书龙 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期284-290,共7页
In this paper, Noether theory of Lagrange systems in discrete case are studied. First, we briefly overview the wellknown Noether theory of Lagrange system in the continuous case. Then, we introduce some definitions an... In this paper, Noether theory of Lagrange systems in discrete case are studied. First, we briefly overview the wellknown Noether theory of Lagrange system in the continuous case. Then, we introduce some definitions and notations, such as the operators of discrete translation to the right and the left and the operators of discrete differentiation to the right and the left, and give the conditions for the invariance of the difference functional on the uniform lattice and the non-uniform one, respectively. We also deduce the discrete analog of the Noether-type identity. Finally, the discrete analog of Noether's theorem is presented. An example was discussed to illustrate these results. 展开更多
关键词 discrete Lagrange system difference functional Noether-type identity Noether-type the-orem
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Limiting stand density and basal area projection models for even-aged Tecomella undulata plantations in a hot arid region of India
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作者 Vindhya Prasad Tewari 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期13-18,I0001,共7页
This paper presents equations for estimating limiting stand density for Z undulata plantations grown in hot desert areas of Raj asthan State in India. Five different stand level basal area projection models, belonging... This paper presents equations for estimating limiting stand density for Z undulata plantations grown in hot desert areas of Raj asthan State in India. Five different stand level basal area projection models, belonging to the path invariant algebraic difference form of a non-linear growth function, were also tested and compared. These models can be used to predict future basal area as a function of stand variables like dominant height and stem number per hectare and are necessary for reviewing different silvicultural treatment options. Data from 22 sample plots were used for modelling. An all possible growth intervals data structure was used. Both, qualitative and quantitative criteria were used to compare alternative models. The Akaike's information criteria differ- ence statistic was used to analyze the predictive ability of the models. Results show that the model proposed by Hui and Gadow performed best and hence this model is recommended for use in predicting basal area development in 12 undulata plantations in the study area. The data used were not from thinned stands, and hence the models may be less accurate when used for predictions when natural mortality is very significant. 展开更多
关键词 model evaluation path invariant algebraic difference form growth function potential density qualitative and quantitative criteria RAJASTHAN
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Association of Metabolic Syndrome with Inflammation in Chinese Adults with Different Kidney Function
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作者 ZHAO Yong WANG Yong Hong LI Xiao Hui 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第10期849-852,共4页
Chronic kidney disease (CKD) has become a worldwide public health problem, and currently, it affects approximately 10% of adults in the United States[I]. Meanwhile, it also has emerged as an important social challen... Chronic kidney disease (CKD) has become a worldwide public health problem, and currently, it affects approximately 10% of adults in the United States[I]. Meanwhile, it also has emerged as an important social challenge in China[2]. CKD has been reported to be a major risk factor for cardiovascular diseases, premature death, and end-stage renal diseaseTM. Thus, it is necessary to determine the risk factors for CKD. 展开更多
关键词 Association of Metabolic Syndrome with Inflammation in Chinese Adults with Different Kidney Function
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The effect of different doses of vecuronium on respiratoty function and mechanics during laparoscopic cholecystectomy
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作者 徐世元 《外科研究与新技术》 2003年第2期70-71,共2页
Objective To investigate the effects of different doses of vecuronium on ventilatory function and mechanics of breathing during elective laparoscopic cholecystectomy. Methods Sixty - three ASA Ⅰ - Ⅱ patients aged 29... Objective To investigate the effects of different doses of vecuronium on ventilatory function and mechanics of breathing during elective laparoscopic cholecystectomy. Methods Sixty - three ASA Ⅰ - Ⅱ patients aged 29 -57 yr were randomly divided into 3 groups of twenty-one: group Ⅰ received vecuronium 1 ± ED95 , group Ⅱ 2 ± ED95 and group Ⅲ ± ED95. Patients with respiratory disease were excluded. The patients were premedicated with intramuscular scopolamine 0 . 3 mg and oral diazepam 0 . 1 mg· kg-1 . Anesthesia was induced with fentanyl 2 μg ·kg-1 ,propofol 2 mg·kg-1 and succinylcholine 1. 5 mg· kg-1 and maintained with 1.0% -1.5% isoflurance and intermittent iv boluses of propofol 1 mg·kg when needed. Vecuronium 1 ± ED95 ( group Ⅰ ) or 2 ± ED95 (group Ⅱ ) or 3 ± ED95 (group Ⅲ ) was given iv after succinylcholine when TOF showed that T1 】 70 % . The patients were mechanically ventilated. VT was set at 10 ml ·kg-1 and respiratory rate at 12 bpm. End-tidal PCO2 was maintained at 30 - 展开更多
关键词 of The effect of different doses of vecuronium on respiratoty function and mechanics during laparoscopic cholecystectomy
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