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221.
Effect of a distal protection device on epicardial blood flow and myocardial perfusion in primary percutaneous coronary intervention 总被引:2,自引:0,他引:2
Objective: The beneficial effect of percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) has been well established, but there is the problem of no-reflow phenomenon which is an adverse prognostic factor in primary PCI. In the present study the effect of a distal protection device (PercuSurge GuardWire; GW) on epicardial blood flow and myocardial perfusion was evaluated. Methods and Results: Patients with AMI were randomly divided into 2 groups, the GW and the control groups. The GW group included 52 patients with AMI who underwent primary PCI with GW protection and the control group included 60 patients who underwent primary PCI without GW protection. Epicardial blood flow in the infarct-related artery (IRA) and myocardial perfusion were evaluated according to the thrombolysis in myocardial infarction (TIMI) flow grade and the myocardial blush grade (MBG). We found TIMI score of 3 was obtained significantly more frequently in the GW group (96%) than in the control group (80%). The MBG score of 3 was obtained also significantly greater in the GW group (65%) than in the control group (33%). Conclusion: Primary PCI with GW protection can significantly improve epicardial blood flow and myocardial perfusion. 相似文献
222.
Relationship between hyperuricemia and metabolic syndrome 总被引:6,自引:0,他引:6
Chen LY Zhu WH Chen ZW Dai HL Ren JJ Chen JH Chen LQ Fang LZ 《Journal of Zhejiang University. Science. B》2007,8(8):593-598
Objective: To investigate the relationship between metabolic syndrome and hyperuricemia. Methods: A total of 2 374 subjects who received health examination in our hospital from Jan. 2004 to Dec. 2006 were enrolled in our study. Hyperuricemia is defined as ≥7 mg/dl (in men) or ≥6.0 mg/dl (in women). Metabolic syndrome was defined using AHA/NHLBI (American Heart Association/National Heart, Lung, and Blood Institute) criteria. Results: (1) The overall prevalence of hyperuricemia was 13.10%. The condition was more common in men than in women (19.07% vs 3.42%). (2) Among men, uric acid concentration is statistically significantly positively correlated with waist circumference, blood pressure, and triglyceride. Uric acid is negatively correlated with serum high-density lipoprotein-cholesterol (HDL-C). Uric acid concentration is most strongly correlated with serum triglyceride (r=0.379) and waist circumference (r=0.297). Among women, statistically significant positive correlations were noted for the serum uric acid concentrations with waist circumference, triglyceride and fasting plasma glucose. Serum triglyceride (r=0.329) and waist circumference (r=0.234) are most strongly correlated with uric acid concentrations. (3) Men with hyperuricemia had a 1.634-fold increased risk of metabolic syndrome as compared with those without hyperuricemia odds ratio (OR)=1.634, P=0.000. Women with hyperuricemia had a 1.626-fold increased risk of metabolic syndrome (OR=1.626, P=0.000) as compared with those without hyperuricemia. Conclusion: Hyperuricemia is prevalent among Chinese population. Additionally, serum uric acid is positively associated with metabolic syndrome. 相似文献
223.
WOMBAT A tool for mixed model analyses in quantitative genetics by restricted maximum likelihood (REML) 总被引:31,自引:0,他引:31
Meyer K 《Journal of Zhejiang University. Science. B》2007,8(11):815-821
WOMBAT is a software package for quantitative genetic analyses of continuous traits, fitting a linear, mixed model; estimates of covariance components and the resulting genetic parameters are obtained by restricted maximum likelihood. A wide range of models, comprising numerous traits, multiple fixed and random effects, selected genetic covariance structures, random regression models and reduced rank estimation are accommodated. WOMBAT employs up-to-date numerical and computational methods. Together with the use of efficient compilers, this generates fast executable programs, suitable for large scale analyses. Use of WOMBAT is illustrated for a bivariate analysis. The package consists of the executable program, available for LINUX and WINDOWS environments, manual and a set of worked example, and can be downloaded free of charge from http://agbu. une.edu.au/~kmeyer/wombat.html 相似文献
224.
225.
Genetic analysis of fruit shape traits at different maturation stages in sponge gourd 总被引:5,自引:0,他引:5
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits (fruit length and fruit perimeter) in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage (1-12 d after flowering) for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage (13-60 datter flowering). The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage. 相似文献
226.
The yeast strain (Y18) was isolated from a soil sample collected from Fildes Peninsula, Antarctica. The strain is a psychrophilic yeast with optimum and maximum growth temperatures of 10 ℃ and 18 ℃, respectively. Teliospores were formed after 7 d on malt agar, when the germination of teliospores was observed. Both inositol and D-glucuronate were assimilated. Positive results of the DBB (diazonium blue B) color reaction, urease test, and starch formation were observed. The major CoQ is Qs. All results indicated that Y18 belongs to the genes of Mrakia. The 18S rDNA sequence analyses showed that Y18 is closely related to Mrakiafrigida. DNA-DNA relatedness study, and some biochemistry characteristics indicated that Y18 represents a new species for which Mrakia psychrophila sp. nov. is proposed. 相似文献
227.
Phonological awareness, phonological memory, and phonological access to lexical storage play important roles in acquiring
literacy. We examined the convergent, discriminant, and predictive validity of these phonological processing abilities (PPA)
in 389 3-, 4-, and 5-year-old children. Confirmatory factor analysis supported the validity of each PPA as separate from general
cognitive ability and separate from each other. Multigroup structural equation modeling (SEM) with mean structure demonstrated
that older preschoolers have better developed latent PPA than younger preschoolers but that the structure of PPA is equivalent.
RAN was found uniquely associated with letter knowledge and text discrimination in younger preschoolers, and PA was found
uniquely associated with word reading skills in older preschoolers. Finally, general cognitive ability was only indirectly
associated with emergent literacy via PPA. These results highlight the importance of PPA in the early literacy development
of English-speaking preschool children. 相似文献
228.
[目的 /意义]公益阅读的可持续发展依赖于有效的资金筹集机制。作为互联网环境下的创新,众筹在公益阅读的筹资中已经体现出积极的作用。探讨公益阅读中众筹融资的影响因素,对于充分发挥这一创新工具的潜力具有重要参考价值。[方法 /过程]以“阅动羊城”公益阅读众筹活动为研究对象,利用网络问卷调查2 860位捐赠者,从道德风险和理性选择的双重视角分析公益阅读中影响众筹融资效果的因素。[结果 /结论 ]数据分析表明,社会资本和对平台的信任等道德风险因素以及捐赠人的特征一起影响着众筹融资的效果,但是,研究未发现参与众筹的成本、精神和物质回报等理性选择因素的影响。在此基础上,从信任和捐赠人识别两个角度提出改善现阶段公益阅读中众筹融资效果的建议。 相似文献
229.
分析了测量布儒斯特角时出现折射波功率大于入射波功率的异常现象原因:在喇叭口面上折射波场的相位偏差小于入射波场的相位偏差,喇叭接收折射波的增益大于接收入射波增益。提出了改进方法。 相似文献
230.