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101.
生物传感器是发展生物技术必不可少的一种先进的检测与监控元件,具有广阔的发展前景,是传感器的一个重要研究方面.本文综述了生物传感器的结构特点、基本原理以及研究现状,探讨了生物传感器的发展趋势.  相似文献   
102.
Ambulatory biosensor assessment includes a diverse set of rapidly developing and increasingly technologically sophisticated strategies to acquire minimally disruptive measures of physiological and motor variables of persons in their natural environments. Numerous studies have measured cardiovascular variables, physical activity, and biochemicals such as cortisol in psychopathology and treatment research. The physiological concomitants of many behavior and medical disorders and the benefits of a multimethod assessment strategy provide strong rationales for clinical applications of ambulatory biosensor measurement. A number of psychometric dimensions of evaluation are important in clinical applications of biosensor measurement, including accuracy and validity, reliability and consistency, clinical utility, incremental validity and utility, sensitivity to change, generalizability, cost benefits, and the conditional nature of dimensions of biomeasure evaluation. The authors review ambulatory biosensor methods and make recommendations for use of the technology. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
103.
Rates of smoking among populations with psychiatric disorders are more than twice as high as among the general population, yet there are few controlled studies of the mechanisms of this relationship. This trial examined the effect of nicotine by way of cigarette smoking on both self-report and autonomic parameters of anxiety among individuals with PTSD who were also heavy smokers. Half of the participants were randomized to an anxiety-eliciting condition, whereas the other half were assigned to a condition of neutral emotional content. Within each of these conditions, participants were randomized into a nicotine condition (high-yield nicotine cigarette) or a placebo condition (denicotinized cigarette). The final layer of randomization involved assigning participants to either an attention-demanding task or a no task condition. We examined the interactive effects of nicotine and attentional demand on parameters of anxious responding. Nicotine exerted an anxiolytic effect relative to placebo on self-report measures; however, nicotine did not interact with attentional demand in producing this effect. In contrast to the findings on the self-report measures of distress, nicotine enhanced autonomic reactivity to trauma cues, thereby suggesting a decoupling of self-reported anxiety and autonomic arousal associated with responding to trauma-relevant cues. The implications for understanding smoking and psychiatric comorbidity are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
104.
Scanning tunneling microscopy (STM) can be used to image individual biological molecules, such as proteins, in vacuum or air. This requires sample dehydration and thus may not reflect the native state of the molecule. Extensive efforts have been made to image single proteins in solution using STM; however, the images have revealed only round or oval shapes with no sub-molecular details. Here, we present the sub-molecular features of streptavidin proteins under physiological conditions using a homebuilt low-leakage-current and highstability liquid phase STM. The N-lobe, C-lobe, and C-terminal tail of the epidermal growth factor receptor kinase domains were also resolved in solution. Our results demonstrate that the structure, morphology, and dynamics of a protein molecule can be examined under physiological conditions by the STM.
  相似文献   
105.
The dynamic self‐organization of lipids in biological systems is a highly regulated process that enables the compartmentalization of living systems at micro‐ and nanoscopic scales. Consequently, quantitative methods for assaying the kinetics of supramolecular remodeling such as vesicle formation from planar lipid bilayers or multilayers are needed to understand cellular self‐organization. Here, a new nanotechnology‐based method for quantitative measurements of lipid–protein interactions is presented and its suitability for quantifying the membrane binding, inflation, and budding activity of the membrane‐remodeling protein Sar1 is demonstrated. Lipid multilayer gratings are printed onto surfaces using nanointaglio and exposed to Sar1, resulting in the inflation of lipid multilayers into unilamellar structures, which can be observed in a label‐free manner by monitoring the diffracted light. Local variations in lipid multilayer volume on the surface is used to vary substrate availability in a microarray format. A quantitative model is developed that allows quantification of binding affinity (K D) and kinetics (kon and koff). Importantly, this assay is uniquely capable of quantifying membrane remodeling. Upon Sar1‐induced inflation of single bilayers from surface supported multilayers, the semicylindrical grating lines are observed to remodel into semispherical buds when a critical radius of curvature is reached.  相似文献   
106.
大豆异黄酮的研究进展   总被引:14,自引:0,他引:14  
介绍了大豆异黄酮的成分及结构,并对大豆异黄酮多种生理功能及其研究进展做了重点阐述。  相似文献   
107.
研究和比较了7个黄瓜品种在自然低温下的生理效应及其产量,结果表明:绿宁3号、寒月和津绿3号的根系活力较高;津优30号、永昌9618、绿宁3号和津绿3号的耐低温性较强;津优30号和津绿3号的畸形瓜少,产量高。在根系活力、耐低温性和产量方面,津优30号和津绿3号最好,津优2号和北极星低。  相似文献   
108.
109.
以基于Windows CE的平板电脑为硬件开发平台,采用VS2005集成开发环境开发了基于Windows CE操作系统的USB驱动和基于Windows CE系统的生理参数监护图形界面软件,并利用平板电脑常见的USB接口作为数据传输接口与生理参数采集模块进行数据通信,以对人体的主要生理参数进行实时监控。经试验显示,该监护系统基本达到了预期的要求。  相似文献   
110.
为解决无市电情况下人体生理参数的长期监测问题,采用近年新推出的光反射器NJL5501R和心电监护模拟前端芯片AD8232,利用动态电源管理、动态时钟频率控制等低功耗技术,设计了一种以STM32L152微处理器为核心的人体生理参数测量系统.实验结果表明:该系统能够完成人体血氧、心电、温度等参数的测量,具有低功耗、小体积的特点,可实现生理参数的长时间监测.  相似文献   
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