膜片钳吉欧封接的电极内微压力控制系统

介绍了一种膜片钳实验用的电极内气动微压力控制系统，使用该系统在膜片钳实验中对大鼠胰腺β细胞进行封接实验，给电极内施加0．5kPa正压入液时，电极电阻平均为5．04MΩ；贴附细胞膜表面后电极电阻均值为；5．44MΩ将电极内压力从正压转变为-3．5kPa左右负压，并将微玻璃电极内电位设为-40mV到-90mV之间，结果显示平均封接电阻达到2．98GΩ．将此结果和人工封接结果进行对比，两者没有显著性差异。     

去除移动心电检测中运动干扰的多通道电极皮肤接触阻抗研究

研究一种多通道电极皮肤接触阻抗检测方法,能够同步检测移动心电信号和电极皮肤接触阻抗信号.该方法不需要改变移动心电检测的输入级,能够通过结构简单的电路来保证移动心电信号放大器的输入阻抗达到足够高.为了评估该方法的性能,10位健康志愿者进行了20组实验,结果显示由多通道电极皮肤接触阻抗信号与移动心电信号中的运动干扰相关性更强（中位数=0.599）.相比现有的单通道电极皮肤接触阻抗检测方法,多通道电极皮肤接触阻抗能够以更简单的电路结构实现更优的性能.      

心肌细胞离子通道的研究进展

<正>Neher和Sakmann于1976年创建了"膜片钳"技术,首次记录到单通道电流。因为测量原理仍与电压(电流)钳相似,但是微电极不再插入细胞内,而是高阻封接在局部膜片上,所以把这种电压(电流)钳位测量方法称为膜片钳。[1]心电生理深入的研究离不开膜片钳技术,其基本方法与经典的微电极技术相似,它记录的是各种跨膜离子流,按方法的不同可作全细胞记录或单通道记录。心肌细胞膜电位靠膜内外离子浓度差维持,内向离子流包括(按惯用符号表示):INa为钠流,INa-B为背景钠流,ICa-L为L-型     

膜片钳技术与PSTAT程序拟合初值的估计

指出了在研究离子通道门控动力学时，首先要对单通道记录进行分析，为进一步建立通道门控的模型提供信息，现在已有了一些分析单通道实验数据的软件包，但在应用这些软件包拟合实验数据时，需要确定拟合的初始值，在多数情况下这是一件困难的事情，结合使用PSTAT软件的经验，提出了选取拟合妆始值的一种直观有效的方法。     

混粉电火花加工介质击穿及放电通道位形研究

回顾了流光理论的基本过程,并运用流光理论对混粉电火花加工极间介质击穿的微观过程进行了详细论述.将粉末颗粒视为插入两电极之间的一串联电极,则极间距离以粉末颗粒为界分成两段,两段介质均以流光的形式击穿后,放电通道便由一电极表面经由粉末颗粒到达另一电极表面而形成串联放电.在此基础上,结合实验现象,研究了放电通道的位形,认为放电过程以单通道放电为主,而正极放电点面积的增大改变了正极表面的热量分布,最终确保了加工表面粗糙度的改善.     

提高膜片钳实验成功率的方法研究

为了研究提高膜片钳实验成功率的方法,该文以大鼠肾上腺髓质嗜铬瘤分化细胞(pc12)的全细胞膜片钳电生理检测实验为例,通过分析实验影响因素和控制关键参数,记录高阻封接、细胞破膜成功率及质量,经实验数据分析,最终确定实验的最优参数。实验表明,在该文实验设备及环境下,提高成功率的最优参数为:玻璃微极管尖端直径为3μm;Ag/AgCl电极电镀电流为0.1 mA,电镀时间为2 h;高阻封接负压在1～2 mL间;破膜负压在0.5～1 mL间;破膜电击刺激延续脉冲为3 ms。     

基于光纤传感的玻璃封接预应力测量

为实现对玻璃中预应力的测量,该文提出了一种基于光纤传感的玻璃封接预应力测量方法。将光纤Bragg光栅传感器植入封接玻璃预留孔中,加热使玻璃熔融,再冷却固化从而使光纤传感器、玻璃、金属同时烧结在一起。通过光纤传感信号的实时监测,实现了对封接温度的实时测量。通过光纤传感信号的变化,计算出了封接玻璃中测量路径的轴向压缩应变,结合有限元分析得到玻璃中的全局应力分布。实验结果表明:光纤传感器可实现对封接过程温度和应力的监测,以玻璃中预应力为指标可以实现对封接工艺的优化。     

纳米火棉胶膜自组装细胞色素c的直接电化学研究

用纳米火棉胶膜将细胞色素c固定在玻碳电极表面,制备了细胞色素c-火棉胶膜修饰电极.吸附在火棉胶膜上的细胞色素c可以与电极发生直接电子传递.在pH=7.0的0.1mol/LPBS缓冲溶液中可得到一对准可逆的细胞色素c的血红素辅基Fe(Ⅲ)/Fe(Ⅱ)电对氧化还原峰,实验求得细胞色素c异相电子传递速率常数k0为65.4μm/s.进一步考察了扫速、溶液pH值等因素对细胞色素c电子传递的影响,并用电化学阻抗法研究了修饰电极的电化学行为.     

一种单通道的源数盲估计方法

针对单通道的源数盲估计技术,提出了一种基于经验模态分解和交叉验证技术相结合的源数估计方法,该方法首先通过经验模态分解技术将单通道的观测信号转换为虚拟的多通道观测信号,然后采用基于交叉验证技术来确定混合在单通道中的源信号个数．仿真实验结果表明：该方法能准确地估计出混合在单通道中服从超高斯分布、亚高斯和高斯分布的源信号个数．     

细胞色素C修饰电极的制备和性能研究

通过自组装法,把血红蛋白细胞色素C固定于导电聚合物(聚谷氨酸)层,制作成一种微型生物传感器,检测其对过氧化氢和亚硝酸钠的响应.实验发现谷氨酸具有一定的电化学活性,循环伏安图在-0.35 V和-0.05 V出现一对氧化还原峰,而且细胞色素C修饰电极对亚硝酸钠响应所得循环伏安图表明,随着亚硝酸钠加入量增大,还原峰增大.通过吸附法修饰电极,把血红蛋白细胞色素C固定于电极表面,探究修饰电极在对苯二胺中的钝化情况.实验表明:细胞色素C修饰电极可以避免电极钝化的发生.细胞色素C作为一种蛋白酶,使对苯二胺处于氧化状态,从而防止电极表面膜的形成,避免电极钝化的发生.     

Engineering Deinococcus radiodurans into biosensor to monitor radioactivity and genotoxicity in environment

Based on a genetically modified radioresistant bacteria Deinococcus radiodurans, we constructed a real time whole cell biosensor to monitor radioactivity and genotoxicity in highly radioactive environ-ment. The enhanced green fluorescence protein (eGFP) was fused to the promoter of the crucial DNA damage-inducible recA gene from D. radiodurans, and the consequent DNA fragment (PrecA-egfp) car-ried by plasmid was introduced into D. radiodurans R1 strain to obtain the biosensor strain DRG300. This engineered strain can express eGFP protein and generate fluorescence in induction of the recA gene promoter. Based on the correlation between fluorescence intensity and protein expression level in live D. radiodurans cells, we discovered that the fluorescence induction of strain DRG300 responds in a remarkable dose-dependent manner when treated with DNA damage sources such as gamma radiation and mitomycin C. It is encouraging to find the widely detective range and high sensitivity of this re-constructed strain comparing with other whole cell biosensors in former reports. These results suggest that the strain DRG300 is a potential whole cell biosensor to construct a detective system to monitor the biological hazards of radioactive and toxic pollutants in environment in real time.     

大鼠背根神经元中Ca2+的激光共聚焦显微成像与定量分析

成功实现体外培养背根神经元(Dorsal Root Ganglion,DRG),利用差速贴壁法进行提纯,通过细胞免疫荧光技术鉴定所培养的细胞纯度,发现其纯度高达90%,完全适合运用于细胞分子机理研究.在此基础上,采用激光共聚焦显微成像实验观察DRG内的Ca2+荧光信号,并对Ca2+浓度进行了定量分析.研究结果有助于深入探究和定量分析神经元中Ca2+参与特定的细胞生理功能.     

A subpopulation of rat dorsal root ganglion neurones is catecholaminergic

The neurotransmitters used by the sensory neurones of the dorsal root ganglia (DRG) are unknown. A proportion of these cells contain physiologically active peptides; for example, subpopulations of small-diameter neurones contain substance P or somatostatin. Although these peptides probably have some influence on synaptic transmission in the dorsal horn of the spinal cord, their status as neurotransmitters is uncertain and it is possible that they coexist with conventional neurotransmitters. In addition, the neurones containing identified peptides account for only a fraction of the DRG sensory neurones. There is evidence that the DRG contain catecholamines within fibres thought to be autonomic, but these substances have not been found within the sensory cell bodies themselves. Moreover, the apparently inappropriate, inhibitory physiological effect of catecholamines in the dorsal horn has argued against their being primary sensory neurotransmitter molecules. We have used here antisera against tyrosine hydroxylase (TH; EC 1.14.16.2) and dopamine-beta-hydroxylase (DBH; EC 1.14.17.1), two enzymes specific to catecholaminergic cells, to show that a subpopulation of rat DRG neurones is catecholaminergic and that the neurotransmitter they make is probably dopamine. We believe this to be the first report of catecholaminergic sensory neurones.     

电磁轨道炮信号控制处理系统的研究

对电磁轨道炮实验系统信号控制与采集进行了描述．利用开关型光耦和线性光耦等元件,进行了信号系统和计算机控制系统隔离与传输的研究．采用ＢｏｒｌａｎｄＣ＋＋Ｗ和ＶＢ语言开发了具有Ｗｉｎｄｏｗｓ界面特点的软件系统应用集成平台．     

Engineering <Emphasis Type="Italic">Deinococcus radiodurans</Emphasis> into biosensor to monitor radioactivity and genotoxicity in environment

Based on a genetically modified radioresistant bacteria Deinococcus radiodurans, we constructed a real time whole cell biosensor to monitor radioactivity and genotoxicity in highly radioactive environment. The enhanced green fluorescence protein （eGFP） was fused to the promoter of the crucial DNA damage-inducible recA gene from D. radiodurans, and the consequent DNA fragment （PrecA-egfp） carried by plasmid was introduced into D. radiodurans R1 strain to obtain the biosensor strain DRG300. This engineered strain can express eGFP protein and generate fluorescence in induction of the recA gene promoter. Based on the correlation between fluorescence intensity and protein expression level in live D. radiodurans cells, we discovered that the fluorescence induction of strain DRG300 responds in a remarkable dose-dependent manner when treated with DNA damage sources such as gamma radiation and mitomycin C. It is encouraging to find the widely detective range and high sensitivity of this reconstructed strain comparing with other whole cell biosensors in former reports. These results suggest that the strain DRG300 is a potential whole cell biosensor to construct a detective system to monitor the biological hazards of radioactive and toxic pollutants in environment in real time.     

血竭对大鼠背根神经节细胞钠通道电流的影响

研究血竭对大鼠背根神经节细胞电压门控性钠通道电流的影响。方法：采用全细胞膜片钳记录法，在新鲜分离的大鼠背根神经节细胞上观察血竭对钠通道电流幅值的影响。结果：血竭剂量依赖地抑制单个DRG细胞电压门控性钠通道电流，高剂量的血竭抑制作用不可逆。结论：血竭对背根神经节细胞钠通道电流的这种抑制作用，可能是其产生躯体镇痛作用的药理机制之一。     

计算机辅助合成全息图

研究合成全息图的原理和记录方法。针对2D／3D合成全息图，分别讨论了对体视、动态、颜色和深度信息的编码以及全息观察窗的空间面积分割，计算了相关的记录参数．实验中采用计算机直接控制的液晶空间光调制器实现2D视差图像的自动显示与切换，方法简便易行，且消除了传统方法中底片复位所产生的误差，易实现自动化生产．实际制作了一个带有动感的合成彩虹全息图，验证了设计的正确性和方法的可行性．     

Monoclonal antibodies against carbohydrate differentiation antigens identify subsets of primary sensory neurones

Dorsal root ganglion (DRG) neurones transmit cutaneous sensory information from the periphery to the spinal cord. Within the dorsal horn of the spinal cord, classes of sensory fibres that are activated by different cutaneous stimuli terminate in separate and highly restricted laminae. Although the developmental events resulting in the laminar organization of sensory afferent terminals have not been defined, it is likely that interactions between surface molecules on DRG and dorsal horn neurones are involved in the generation of afferent synaptic connections. The identification of surface antigens that distinguish functional subclasses of DRG neurones would represent a first step in establishing the existence and nature of such molecules. We report here that monoclonal antibodies directed against carbohydrate differentiation antigens identify cytoplasmic and cell surface molecules expressed selectively by functional subsets of DRG neurons.     

膛内多力学量测试技术研究

该文采用了膛内环境硬线测试技术,使用微机系统进行了包括膛压、加速度、碰击力和应变在内的内弹道多力学量数据的一次性测试和数据处理。文章介绍了测试设备和仪器的选用,详细地讨论了测试系统中的4个主要子系统:发射系统,加速度、膛压、碰击力和应变传感装置,数据采集、记录和分析系统和以及回收系统。对测试中所得到的力信号和应变信号进行了信号分离,同时对应变误差进行了修正。     

Central nervous system and peripheral nerve growth factor provide trophic support critical to mature sensory neuronal survival

Primary sensory neurones in cranial and dorsal root ganglia (DRG) of adult animals are generally thought to be maintained through connections with their peripheral (but not central) targets by trophic factor(s) other than nerve growth factor (NGF). Damage to the peripheral process of sensory neurones results in a dramatic response or even death of the neurones, whereas axotomy (cutting) of the central process does not initiate profound reaction in these neurones. The development and maintenance of neurones are highly dependent on a supply of trophic agents produced by targets and retrogradely transported via the peripheral process to the cell body. NGF deprivation in fetal rodents produced either by exogenously administered antibodies or by those of maternal origin, results in death of DRG and of some cranial sensory neurones. However, as chronic NGF deprivation in neonatal or adult rodents produces little or no cell death, it has been assumed that some other trophic factor(s) derived from the peripheral target sustains sensory neurones in postnatal life. By inducing NGF deprivation by autoimmunizing guinea pigs with mouse NGF and/or by cutting the central root (process) of a DRG, we demonstrate here that under certain conditions DRG neurones require NGF and centrally derived trophic support. Our results indicate that sensory neurones are maintained by the trophic support provided by both peripheral and central targets. This support is mediated by NGF and other as yet unidentified trophic factors. The relative importance of the two target fields and NGF compared with other trophic factors changes during development.