钙离子在海马脑片缺氧损伤中的作用

本工作用海马脑片缺氧模型,观察了无钙、高镁人工脑脊液以及钙通道阻断剂尼莫地平对缺氧后海马脑片ＣＡ１区锥体细胞诱发群锋电位（ＰＳ）的影响。发现用无钙与高镁人工脑脊液灌流脑片,可显著促进脑片缺氧后ＰＳ的恢复,而尼莫地平对缺氧脑片ＰＳ的恢复则无明显促进作用。结果表明：钙离子参与海马脑片缺氧后神经元及其突触传递的损伤过程,而电压敏感性钙通道Ｌ亚型在缺氧损伤中可能不起主要作用。     

缺氧对大鼠海马脑片诱发电位的影响

在脑缺氧损伤的研究中,离体海马切片既可排除血脑屏障,又保持原有神经环路,所得实验结果接近在体实验,是研究脑缺氧的理想模型。近几年来国外已有人报道了缺氧时海马脑片诱发电位的变化;但同时用两个脑片比较不同程度的低氧对脑片诱发电位的影响,却少有报道。本实验采用自行设计的双孔脑片电生理实验系统,用不同浓度的低氧混合气造成不同程度的缺氧环境,以探明不同缺氧程度影响脑片电反应的时间曲线,寻求海马脑片缺氧损伤的特征性反应与不可逆损伤发生的临界值。     

钙离子在海马脑片缺氧损伤的作用

本工作用海马脑片缺氧模型,观察了无钙、高镁人工脑脊液以及钙通道阻断剂尼莫地平对缺氧后海马脑片ＣＡ１区锥体细胞诱发群锋电位（ＰＳ０的影响。发现用无钙与高镁人工脑脊液流脑片,可显著促进脑片缺氧后ＰＳ的恢复,而尼莫地对缺氧脑片ＰＳ的则无明显促进作用。结果表明：钙离子参与海马脑片缺氧后神经元及其突触传递的损伤过程,而电压敏感性通道Ｌ亚型在缺氧损伤中可能不起主要作用。     

介绍一种电药理实验的4孔脑片浴槽

目的：介绍一种同时进行４路流体灌流的多孔脑片浴槽。方法：用大鼠朋脑皮层脑片细胞外电极记录，观察自发性癫痫样放电。结果：通过染料试验证明４路液体互不通连。用无Ｍｇ＾２＋和含３０μｍｏｌ／Ｌ４－氨基吡喧的人工脑脊液灌流１ｈ后，各孔脑片均可出现自发性放电，并可维持稳定达３ｈ以上。结论：此装置可以同时观察４种抗癫痫药物对脑片自发放电的抑制作用。     

白藜芦醇抑制大鼠下丘脑脑片室旁核神经元放电

本文旨在研究白藜芦醇(resveratrol)对下丘脑脑片室旁核神经元放电的影响.应用玻璃微电极细胞外记录单位放电技术,在下丘脑脑片上观察白藜芦醇对静息状态下室旁核神经元放电的影响.结果如下:(1)在29张下丘脑脑片室旁核神经元放电单位给予白藜芦醇(O.05,0.5,5.0 μmol/L)2 min,有28张脑片(96.6%)放电频率显著降低,且呈剂量依赖性;(2)预先用0.2mmol/L的L.glutamate灌流8张下丘脑脑片,8张脑片(100%)放电频率显著增加,表现为癫痫样放电,该放电可被白藜芦醇(5.0 μmol/L)灌流2 min抑制:(3)预先用L型钙通道开放剂Bay K8644(0.1μmol/L)灌流8张下丘脑脑片,8张脑片(100%)放电频率显著增加,该放电可被白藜芦醇(5.0 μmol/L)灌流2 min抑制;(4)用一氧化氮合酶抑制剂Nω-nitro.L-arginine methyl ester(L-NAME)50μmol/L灌流8张下丘脑脑片,7张脑片(87.5%)放电频率显著增加,该放电可被白藜芦醇(5.0 μmol/L)灌流2 min抑制.以上结果提示,白藜芦醇抑制下丘脑室旁核神经元自发放电,可能通过降低心血管中枢的活动性而产生中枢保护作用.这种抑制作用可能与白藜芦醇抑制L型钙通道、减少钙内流有关,与NO释放无关.     

以突触前排放的消失设定海马脑片缺氧损伤时间及应用实例

刺激Schaffer侧支,记录大鼠海马脑片CA_1区的突触前排放(presynaptic volley,PV)和突触后群锋电位(population spikes,PS),观察缺氧后PS和PV的变化及复氧30min后脑片PS的恢复,缺氧持续到PV消失1,2,3或4min,复氧后脑片恢复率分别为100％,11.5％,0％,0％。可见,缺氧后 PV 消失2min为损伤的关键时刻。提前1min终止缺氧,全部脑片的PS可以恢复,延迟1min终止缺氧,则全部脑片的PS不能恢复。这种方法是根据每个脑片的电反应确定其总的缺氧时间,故每个脑片的缺氧时间略有变动。与每次采用相同缺氧时间的传统方法相比,此方法脑片恢复率的稳定性与重复性均较好。用此方法发现美西律10和100μmol/L能增加复氧后PS恢复率,对突触功能的缺氧损伤具有保护作用。     

小鼠海马神经元冰冻切片和脑片培养方法的比较

目的:通过冰冻切片和脑片培养方式比较获得更适合脑片实验研究的方法。方法:分别运用急性切片和脑片培养方法,结合全细胞膜片钳技术比较两种脑片处理方法对小鼠海马神经元细胞形态、细胞膜封接难易程度、细胞电生理特性等的差异,获得更适合细胞研究的脑片获取方法。结果:冰冻切片方法切断部分神经纤维,脑片表层出现肿胀或坏死细胞,2-3层细胞可用于膜片钳记录,但不易封接破膜。脑片培养后可使纤维再生,整个脑片细胞形态清晰可见,容易封接破膜,电生理记录波形及基本特性与冰冻切片一致,但脑片培养方法的细胞突触后电流幅度更大、频率更高。结论:脑片培养可修复受损纤维和细胞膜柔韧性,且不改变膜特性,但脑片培养重建了一定数量的细胞间信号连接,使细胞反应性增强,脑片培养方法更适合脑片神经元研究。     

钩藤对致痫大鼠海马脑片诱发场电位的影响

目的研究钩藤对癫痫模型海马脑片诱发场电位的影响。方法以毛果芸香碱致痫大鼠为实验对象,采用脑片旁滴注给药,用细胞外玻璃微电极记录方法,观察钩藤对癫痫模型离体海马脑片CA1区锥体细胞诱发群锋电位（populationspike,PS）的影响。结果给予钩藤后使致痫大鼠海马脑片PS幅度平均降低27.64％,平均8.71min恢复(n=14,P<0.01)。结论钩藤能降低致痫大鼠海马脑片CA1区顺向诱发PS幅度,提示钩藤对中枢神经系统的突触传递过程有明显的抑制效应,具有抗癫痫作用。     

GABA对大鼠海马脑片缺氧损伤的保护作用

目的：研究GABA对大鼠海马脑片急性缺氧损伤的保护机制。方法：采用成年大鼠离体海马脑片,用胞外记录的电生理技术,观察GABA对急性缺氧后海马脑片诱发电位的影响。结果：（1）GABA可明显延迟PV的消失,但对PS却无影响;（2）给予GABAA受体拮抗剂荷包牡丹碱（bicuculine)以及Cl^-通道阻抗剂NPPB可阻断GABA的保护作用。结论：GAB可提高海马脑片耐缺氧能力,其机制可能与GABA通过GABAA受体提高Cl^-内流有关。     

温度对不同年龄大鼠海马器官型脑片长期培养中细胞活性和tau蛋白表达的影响

探讨在海马器官型脑片的长期培养过程中,温度对不同年龄大鼠的海马脑片细胞活性和tau蛋白表达的影响,并以此为依据建立一种研究tau相关疾病的模型.选用出生后1周、2周、4周和8周的Wistar大鼠制备海马器官型脑片,培养温度分别为34℃和37℃,培养时间为21d,在培养过程中,检测培养基中的乳酸脱氢酶的含量以判断脑片的活性,采用免疫印迹技术检测细胞骨架蛋白tau的含量的变化.结果如下:(1)温度对海马脑片的细胞活性影响:34℃较37℃能在较长的时间内保持细胞活性,而在同一培养温度时,不同年龄鼠的脑片的细胞活性变化趋势一致;(2)温度对海马脑片的tau蛋白表达的影响:成年鼠(4周和8周)的海马脑片tau蛋白在34℃时能维持较长时间的稳定表达,而在37℃时tau的表达量随培养时间的延长而显著下降,且随鼠龄的增加,这种影响越明显.温度对1周和2周龄乳鼠的海马脑片tau蛋白的表达无影响.结论为:34℃培养条件下,4周和8周龄大鼠制备的海马器官型脑片能更长时间维持脑片的活性和tau蛋白的稳定表达,从而可望成为研究与tau蛋白相关疾病(如老年性痴呆)的理想模型.     

蝽科Dalpada属群的系统发育分析(半翅目)

作者对Halyini族中Dalpada属群的9个属级阶元的代表属作了形态学研究,选取头、翅、腹部、雌、雄外生殖器以及受精囊等方面的18项形态特征,运用PAUP程序进行支序分析,得出该属群的属级关系支序图,并对该属群的系统发育进行了讨论。     

An algol program for the computation of empiric regressions

An explanation is given about the meaning of empirical regression and on the domain of application of this biomathematical-statistical procedure. It may be helpful in data handling after the measurements and in a first stage of data processing especially if there is a large amount of datas. An empirical regression can provide the basis for a functional relationship analysis by giving hints for the choice of empirical mathematical functions. This will be useful and necessary in such cases where the measured values have a greater dispersion and one wants to get an analytical expression for the course of measured points. In the appendix a program listing of the ALGOL-program for empirical regression is presented. Detailed remarks are made in the text concerning the program structure, the data input and output resp. the program control parameters to enable the biological or medical user to adapt the program to their special problems without the help by a mathematician, and neither with deeper knowledge of mathematics nor with detailed insight to computer technical aspects of data processing.     

Application of Fast Fourier Transform in Electroencephalography

Today the Fourier Transform is also used in the analysis of biological time series with periodical parts. For N = 2^M EEG sampling values the Fast Fourier Transform algorithm of COOLEY and TUKEY is applicable. For this a FORTRAN IV program EEG-FFT has been developed for computation of power spectrum. At the data processing equipment EC 1040 the CPU-time for 2¹⁰ = 1024 EEG sampling values is smaller than 1.5 s. The FORTRAN IV program can be applied both in offline and online data processing.     

DnaSAM: Software to perform neutrality testing for large datasets with complex null models

Patterns of DNA sequence polymorphisms can be used to understand the processes of demography and adaptation within natural populations. High-throughput generation of DNA sequence data has historically been the bottleneck with respect to data processing and experimental inference. Advances in marker technologies have largely solved this problem. Currently, the limiting step is computational, with most molecular population genetic software allowing a gene-by-gene analysis through a graphical user interface. An easy-to-use analysis program that allows both high-throughput processing of multiple sequence alignments along with the flexibility to simulate data under complex demographic scenarios is currently lacking. We introduce a new program, named DnaSAM, which allows high-throughput estimation of DNA sequence diversity and neutrality statistics from experimental data along with the ability to test those statistics via Monte Carlo coalescent simulations. These simulations are conducted using the ms program, which is able to incorporate several genetic parameters (e.g. recombination) and demographic scenarios (e.g. population bottlenecks). The output is a set of diversity and neutrality statistics with associated probability values under a user-specified null model that are stored in easy to manipulate text file.     

Assembly of overlapping DNA sequences by a program written in BASIC for 64K CP/M and MS-DOS IBM-compatible microcomputers.

The SEQALIGN programs1 described in this report aid in the assembly of up to 100 individual overlapping DNA sequences generated by M-13 subcloning and sequencing methods. The program produces a printout of the aligned sequences presented in register. Use of the program will be facilitated because 1) it is written with the Microsoft BASIC interpreter, 2) sequence data may be entered and edited using WORDSTAR or similar word processing programs, and 3) hardware requirements for execution of the program on CP/M or MS-DOS (IBM-PC compatible) systems are minimal.     

A computer method for analysis of radioactivity data from single and double labeled experiments

A generally applicable program has been devised for the machine processing and plotting of radioactivity data. The program can be used with single or double labeled experiments; it includes numerous options which increase its flexibility and facilitate optimization of data presentation.     

昆虫飞行模拟监控系统设计

本文根据昆虫飞行的特点,模拟昆虫飞行的实验装置,由飞行磨、单片机及微型计算机组成,编辑设计飞行监控软件,该程序分为三个模块：系统监控程序模块;时钟程序模块和信号处理程序模块。利用微机适时采集飞行数据,记录和分析监测结果,模拟昆虫的飞行速度和持续时间。     

Development of a target component extraction method from GC-MS data with an in-house program for metabolite profiling

After gas chromatography-mass spectrometry (GC-MS) analysis, data processing, including retention time correction, spectral deconvolution, peak alignment, and normalization prior to statistical analysis, is an important step in metabolomics. Several commercial or free software packages have been introduced for data processing, but most of them are vendor dependent. To design a simple method for Agilent GC/MS data processing, we developed an in-house program, "CompExtractor", using Microsoft Visual Basic. We tailored the macro modules of an Agilent Chemstation and implanted them in the program. To verify the performance of CompExtractor processing, 30 samples from the three species of the genus Papaver were analyzed with Agilent 5973 MSD GC-MS. The results of CompExtractor processing were compared with those of AMDIS-SpectConnect processing by hierarchical cluster analysis (HCA) and principal component analysis (PCA). The two methods showed good classification according to their species in HCA. The PC1+PC2 scores were 54.32-63.62% for AMDIS-SpectConnect and 56.65-85.92% for CompExtractor in PCA. Although the CompExtractor processing method is an Agilent GC-MS-specific application and the target compounds must be selected first, it can extract the target compounds more precisely in the raw data file with batch mode and simultaneously assemble the matrix text file.     

活体细胞三维图像科学可视化方法的研究

科学可视化是指运用计算机图形学和图像处理技术,将科学计算过程中或者是计算结果的数据转换为图形或图像,在屏幕上显示出来并进行交互式处理的理论技术或方法。介绍了用反卷积荧光显微成像技术获得活体大鼠胰腺B细胞三维图像及对其进行科学可视化的主要过程和两种常用可视化算法,并运用这两种方法对所得到的三维图像进行处理以分析和研究细胞内分泌囊泡的空间分布。结果显示,当仅观察细胞三维图像的二维切片时,三维图像中的某些重要信息会被忽略,而使用科学可视化方法则可以从三维角度直观观察活体细胞内分泌囊泡的空间分布,并且可以观察到分泌囊泡的释放趋势和整体分布,从而为细胞生物学研究提供重要的信息。     

基于Bioperl实现远程自动获取抗逆基因序列

BioPerl对于现今大量的生物数据来说,具有很好的获取和处理能力,并且NCBI提供了可以直接访问它下属的Entrez数据库（包括PubMed）的编程接口,即E-Utilities。为了从NCBI中自动获取大量抗逆基因序列,使得生物抗逆基因二次数据库得以搭建,该文基于BioPerl设计了远程自动获取大量抗逆基因序列的程序。此程序灵巧、精悍,Perl语言强大的文本处理功能使程序能实现不同类型基因序列的远程获取。