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1.
Hypertonia, which results from motor pathway defects in the central nervous system (CNS), is observed in numerous neurological conditions, including cerebral palsy, stroke, spinal cord injury, stiff-person syndrome, spastic paraplegia, dystonia and Parkinson disease. Mice with mutation in the hypertonic (hyrt) gene exhibit severe hypertonia as their primary symptom. Here we show that hyrt mutant mice have much lower levels of gamma-aminobutyric acid type A (GABA(A)) receptors in their CNS, particularly the lower motor neurons, than do wild-type mice, indicating that the hypertonicity of the mutants is likely to be caused by deficits in GABA-mediated motor neuron inhibition. We cloned the responsible gene, trafficking protein, kinesin binding 1 (Trak1), and showed that its protein product interacts with GABA(A) receptors. Our data implicate Trak1 as a crucial regulator of GABA(A) receptor homeostasis and underscore the importance of hyrt mice as a model for studying the molecular etiology of hypertonia associated with human neurological diseases.  相似文献   
2.
Polytene chromosome structure in relation to the "folded fibre" concept   总被引:4,自引:0,他引:4  
E J DuPraw  P M Rae 《Nature》1966,212(5062):598-600
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3.
Hydrogen is a promising energy carrier that can potentially facilitate a transition from fossil fuels to sustainable energy sources without producing harmful by-products. Prior to realizing a hydrogen economy, however, viable hydrogen storage materials must be developed. Physical adsorption in porous solids provides an opportunity for hydrogen storage under low-stringency conditions. Physically adsorbed hydrogen molecules are weakly bound to a surface and, hence, are easily released. Among the various surface candidates, porous carbons appear to provide efficient hydrogen storage, with the advantages that porous carbon is relatively low-cost to produce and is easily prepared. In this review, we summarize the preparation methods, pore characteristics, and hydrogen storage capacities of representative nanoporous carbons, including activated carbons, zeolite-templated carbon, and carbide-derived carbon. We focus particularly on a series of nanoporous carbons developed recently: metal–organic framework-derived carbons, which exhibit promising properties for use in hydrogen storage applications.  相似文献   
4.
周作人在<谈龙集·上海气>中说"我终于是一个中庸主义的人."看来周作人对自己的了解是很深的.对于周作人的复杂人格,任何一种简单化的说明都是有害的,因此,以矛盾分析的办法以及与鲁迅进行人格对比的方法,论证鲁迅的人格是殉道的、苦行主义的,而周作人的人格则是中庸的、现世主义的,对于探讨周作人的人格的形成、发展以及内在矛盾,并以此关照中国现代社会条件之下知识分子的精神处境以及人格分裂问题,也许不无意义.  相似文献   
5.
1. Introduction Robust design (RD) techniques based on the concept of building quality into a design are increasingly popular in industry primarily because of their practicality. There have been many attempts to integrate Taguchi’s RD principles with well-established statistical techniques, such as response surface methodology (RSM), in order to model the response directly as a function of control factors (Vining and Myers 1990). RSM is a collection of mathematical and statistical techni…  相似文献   
6.
基于长三角地区1995—2018年数据,从总体水平、产业层次、区域层次等角度分析,探究能源消费、CO2排放量对区域经济增长的影响.研究结果表明:CO2排放量与经济增长、能源消费与经济增长之间均存在着长期互为正向影响的关系,且具有积极性的影响,经济增长与CO2排放量以及经济增长与能源消费二者之间存在单方向的线性关系,经济...  相似文献   
7.
多肽标记的量子点已经被广泛应用于肿瘤细胞成像, 特别是靶向多肽标记的量子点能够特异性地标记细胞从而识别肿瘤. 然而到目前为止, 还没有靶向多肽标记的量子点用于结肠癌肿瘤组织成像. 本文合成了一种双功能的TCP-1-H6多肽, 这种多肽既有TCP-1的靶向性, 又含有一个组氨酸标签(His-tag). 多肽与量子点可以通过His-tag偶联并通过毛细管电泳表征. TCP-1可以特异性地识别结肠癌细胞的受体. 实验结果表明, 靶向多肽标记的量子点能特异性地识别结肠癌细胞及肿瘤组织. 这一工作对肿瘤细胞的识别诊断研究具有重要的参考价值.  相似文献   
8.
采用对偶性技巧、Hoelder不等式、线性抛物型方程正则性理论等一系列非线性分析的方法,研究一类带有交错扩散影响的非线性生物种群迁移与竞争控制系统模型,在R^n(2≤n≤4)的任何有界光滑区域并带有一般边界条件的情况下,得到系统解的整体存在性。  相似文献   
9.
模糊可靠性分析改进的一次二阶矩法   总被引:5,自引:0,他引:5  
给出了模糊变量变换为当量随机变量时,其当量概率密度函数、当量均值和当量标准差的一般表达式,得到了采用几种常用隶属函数模糊变量的当量均值和当量标准差的具体计算式.根据极限状态方程,用传统可靠性理论中改进的一次二阶矩法计算复杂情况下的模糊可靠性,获得了衡量模糊可靠性的可靠性指数.算例验证了方法的有效性和实用性.  相似文献   
10.
We investigate the feasibility of dual-energy method for image contrast enhancement in small animal studies using a low kV X-ray radiographic system.A robust method for X-ray spectrum estimation from transmission measurements,based on expectation-maximization(EM) method,is applied to an X-ray specimen radiographic system for dual energy imaging of a mouse.From transmission measurements of two known attenuators at two different X-ray tube voltages,the X-ray energy spectra are reconstructed using the EM-based...  相似文献   
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