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311.
伴随着我国的市场经济的快速发展,我国水利工程建设水平也得到了相应的发展和进步。然而,在水利工程概算的问题上,仍然存在很多不尽如人意的弊端。针对近年来我国水利工程概算超支的现象进行调查走访和逻辑分析,发现相应的问题产生源头,针对具体问题作出具体分析,提出相应的解决措施,力争对我国水利水电工程概算提供有力的理论借鉴,促进我国国民经济的稳步发展。  相似文献   
312.
Rehabilitation is the most effective way to reduce motor impairments in post-stroke patients.This process demands several hours with a specialized therapist.Given resources and personnel shortages,the literature reports a high interest in robotic assisted rehabilitation solutions.Recently,cable-driven robotic architectures are attracting significant research interest for post-stroke rehabilitation.However,the existing cable-driven robots are mostly unilateral devices allowing the rehabilitation only of the most affected limb.This leaves unaddressed the rehabilitation of bimanual activities,which are predominant within the common Activities of Daily Living(ADL).Thus,this paper presents a specific novel design to achieve bimanual rehabilitation tasks that has been named as BiCAR robot.Specifically,this paper provides a full insight on the BiCAR sys-tem as well as on its dedicated developed software BiEval.In particular,BiEval software has been developed as based on a serious game strategy and a virtual reality environment to track the patient exercising duration,motion ranges,speeds,and forces over time for achieving a quantitative assessment of the rehabilitation progress.Finally,the paper presents the BiCAR/BiEval capabilities by referring to a pilot Randomized Controlled Trial(RCT).The clinical trials have been used to validate the BiCAR/BiEval in terms of engineering feasibility and user acceptance to achieve an innovative cost-oriented integrated hardware/software device for the bimanual assistive rehabilitation of post-stroke patients.  相似文献   
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314.
本工作观察了猕猴在自由或限制条件下学习视觉或听觉分辨的规律。在WGTA内动物对颜色分辨学习有很大的个体差异,主要表现为学习初期正确反应率在机率水平波动的持续时间的不同。猴在WGTA内完成亮暗、物体及图形分辨学习,以及在限制椅上完成颜色分辨学习也有类似情况。从同一只猴在WGTA内进行不同的视觉分辨任务的学习所得的结果表明,物体分辨和亮暗分辨学习比之颜色分辨学习要容易些,图形分辨学习则相对地比较困难。猴在限制椅上学习颜色分辨比在WGTA内需要更多的测试数。动物在限制椅上学习纯音音调分辨似乎更为困难。这些结果对神经精神药理学、心理生理学以及神经生理学研究中选择合适的动物实验模型有一定的参考价值。  相似文献   
315.
Protein arginine methyltransferases(PRMTs) catalyze the methylation of a variety of protein substrates, many of which have been linked to the development, progression and aggressiveness of different types of cancer. Moreover, aberrant expression of PRMTs has been observed in several cancer types. While the link between PRMTs and cancer is a relatively new area of interest, the functional implications documented thus far warrant further investigations into its therapeutic potential. However, the expression of these enzymes and the regulation of their activity in cancer are still significantly understudied. Currently there are nine main members of the PRMT family. Further, the existence of alternatively spliced isoforms for several of these family members provides an additional layer of complexity. Specifically, PRMT1, PRMT2, CARM1 and PRMT7 have been shown to have alternative isoforms and others may be currently unrealized. Our knowledge with respect to the relative expression and the specific functions of these isoforms is largely lacking and needs attention. Here we present a review of the current knowledge of theknown alternative PRMT isoforms and provide a rationale for how they may impact on cancer and represent potentially useful targets for the development of novel therapeutic strategies.  相似文献   
316.
Chlorophyll fluorescence transient from initial to maximum fluorescence("P" step) throughout two intermediate steps("J" and "I")(JIP‐test) is considered a reliable early quantitative indicator of stress in plants. The JIP‐test is particularly useful for crop plants when applied in variable field environments. The aim of the present study was to conduct a quantitative trait loci(QTL) analysis for nine JIP‐test parameters in maize during flowering in four field environments differing in weather conditions. QTL analysis and identification of putative candidate genes might help to explain the genetic relationship between photosynthesis and different field scenarios in maize plants. The JIP‐test parameters were analyzed in the intermated B73 Mo17(IBM) maize population of 205 recombinant inbred lines. A set of 2,178 molecular markers across the whole maize genome was used for QTL analysis revealing 10 significant QTLs for seven JIP‐test parameters, of which five were co‐localized when combinedover the four environments indicating polygenic inheritance and pleiotropy. Our results demonstrate that QTL analysis of chlorophyll fluorescence parameters was capable of detecting one pleiotropic locus on chromosome 7, coinciding with the gene gst23 that may be associated with efficient photosynthesis under different field scenarios.  相似文献   
317.
正Dear Editor,Increasing number of hepatitis E virus(HEV)infection has been described in industrialized countries,with infection occurring as a sporadic disease,usually associated with travel to endemic regions or small outbreaks due to ingestion of contaminated food or water.More recently some cases were found to be associated with zoonotic  相似文献   
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