Computer simulations and the use of radiolabelled sulphur colloid to measure the efficiency of the mononuclear phagocyte system

Technique are described whereby the clearance of the radiolabelled blood borne colloid can be continuously and reproducibly measured non-invasively from the same animal in vivo or from the isolated perfused intact liver in vitro. Using these techniques, the rate of removal of radiolabelled sulphur colloid by the mononuclear phagocytes in vivo and in vitro was shown to be biexponential. The pattern of clearance of colloid and the factors contributing to this were analysed with the aid of a computer program which mimicked the in vitro liver perfusion.     

心脏螺旋波演化与驱动的计算机实验

我们利用FitzHugh-Nagumo(FHN)类型方程,对二维心肌可激媒质系统螺旋波(Spiral wave,SW)的形成、演化和控制进行了数值模拟,主要有以下研究结果:(1)改变系统的可激性,不会影响SW的激发区宽度,却改变SW的自转周期和旋波核的大小;当可激性达到某一极限值时,SW的自转周期与旋波核的半径趋于无穷大,系统不再出现SW。(2)对SW的均匀近共振小电流驱动,可以引导旋波头(Spiral wave tip,SWT)的漂移运动;当驱动频率接近SW的自转频率时,SWT会沿着圆周漂移,当驱动频率达到共振频率时,SWT会沿着直线漂移。     

Neurophysiological and psychological predictors of genetic risk for schizophrenia

Mathematical genetic analyses were performed on a sample of schizophrenic families (25 probands and 58 first-degree relatives). Heritability coefficients were estimated for EEG power spectrum parameters and their topography, and also for psychological test data on thought and speech process disorder, designed to assess altered selectivity in cognitive activity. Multiple regression equations for genetic counseling regarding the prognosis of mental illness were derived from the neurophysiological and psychological measures.     

线扫描直接数字化X线摄影原理与应用

目的 探讨线扫描直接数字化X线摄影的工作原理与实用价值。方法 以多丝正比室线扫描X线摄影系统为基础，分析线扫描直接数字化X线摄影的适用性。结果 线扫描成像技术克服了散射线造成的干扰，且探测灵敏度和精密度分辨率高。结论 线扫描成像技术适合于除了动态摄影以外的各种数字X线摄影，对我国常规X线摄影逐步实现数字化开辟了美好的前景。     

B族链球菌C5a肽酶蛋白表位的克隆、表达和免疫学分析

目的应用生物信息学方法预测B族链球菌C5a肽酶蛋白表位，结合基因工程手段进行表位重组、表达和免疫原性分析。方法用预测程序ProPred和ANTIGENIC预测B族链球菌C5a肽酶蛋白的表位，应用PCR技术扩增出编码该表位基因片段，克隆PCR产物构建重组质粒，测序验证。在大肠杆菌BL21（DE3）中诱导表达融合蛋白。表达的蛋白经质谱分析和Western blot鉴定。纯化该融合蛋白并免疫C57／BL小鼠，萃取GBS表面蛋白，双向琼脂扩散试验检测抗体水平。结果在SCPB中预测到1个既具有MHC结合肽特性又具有B细胞表位特征的肽段。重组和表达了这一肽段，质谱得出与SCPB蛋白的相似性分数为79，Western-blot证实能与抗SCPB的抗体反应，纯化后融合蛋白纯度〉90％。动物实验证实融合蛋白能产生特异性的抗GBS抗体。结论重组表位具有一定免疫原性。为相关蛋白的毒力机制研究和亚单位疫苗等方面的研究打下了良好的基础。     

Computer Simulations of the “Hairy Rod” Model

Summary: Using extensive Molecular Dynamics simulations we study the behavior of very rigid polyelectrolytes with hydrophobic side chains that are known to form cylindrical micelles in aqueous solution. We investigate the stability of such micelles with respect to hydrophobicity, Coulomb interaction, and micellar size. We show that for the parameter range relevant for poly(p‐phenylene sulfonate)s (PPP) one finds a stable finite micellar size close to the experimental parameter region. We also point out that our model has some similarities to DNA solutions with added condensing agents, hinting to the possibility that the size of DNA aggregates is under certain circumstances thermodynamically limited.

DNA‐like morphologies of the polyelectrolytes.     

形态测量在胃癌病理—生物学分型中的价值

生物学行为是影响胃癌预后的重要因素而核面积是影响因素中最重要一个。本文按生长方式对胃癌作了新的病理生物学分型的尝试,把胃癌分作膨胀型和浸润型,每型又依核面积大小分为大核型和小核型。结果表明,本文的分型较其他分型更能体现肿瘤的生物学特性,值得提倡。     

A computer-interfaced photometer and systematic spacing of duplicates to control within-plate enzyme-immunoassay variation

A Multiskan photometer for reading microtiter plate enzyme immunoassays was linked with a time sharing computer to facilitate control of assay variation and analysis of results. The interface that converted photometer output to RS-232-C format required changes to divide the output into segments short enough for input to the computer. To measure within-plate variation and investigate how the method of allocating sample duplicates to plate wells may affect the estimation of sample variance, uniformity tests were conducted with 47 plates. Coefficients of variation (CV) among wells within-plates ranged from 4.6 to 20.7% and in two-thirds of the plates exceeded 10%. Duplicates allocated to adjacent wells (method 1) gave consistently higher CV for sample means than duplicates allocated to opposite plate quadrants (method 2). In general, the CV by method 2 was about 30% smaller than that by method 1. Analysis of variance confirmed the effectiveness of the quadrant pattern of duplicate allocation as a method of controlling variation that arises from well position effects.     

腭部恶性肿瘤的CT诊断

探讨腭部恶性肿瘤的CT表现及其诊断价值。回顾性分析32例经病理证实的腭部恶性肿瘤的CT表现,其中男27例,女5例。所有病例均行横断增强扫描,其中8例同时行平扫,2例加冠状位扫描。腭部恶性肿瘤的CT表现为:(1)腭部肿块(26例)、腭部软组织增厚(6例)和腭骨质破坏(6例),其中病变位于软腭(22例)、硬腭(4例)、软硬腭交界处(3例);(2)邻近结构受累及(27例);(3)颈部淋巴结转移(17例)。CT是一种优良的检查技术,能显示腭部恶性肿瘤的大体病理改变以及侵犯途径,为临床治疗和预后提供重要信息。     

Biomorphometric analysis of human prostatic carcinoma by using three-dimensional computer models

Advances in the detection of carcinoma of the prostate during the last 15 years have accounted for a sharp increase and then an abrupt decrease in the incidence of the disease. A more recent decline in its mortality rates has been variously interpreted as either the success of early detection and improved treatment or lead-time bias. The recently reported Prostate Cancer Prevention Trial had an overall detection rate that approached the 30%-40% prevalence rates reported in autopsy series in which men died of other causes. However, the prognostic information that can be obtained from prostate cancer found on biopsy is limited. Three-dimensional computer modeling is one technique that allows multiple studies on "immortal" prostates to test methods of biopsy sampling accuracy and to assist in the determination of the disease's severity. Computer modeling can assess detection rates and assesses tumor multifocality and heterogeneity. It can provide a more accurate representation of tumor volume, aiding in therapeutic decision making, and can assess sampling errors of various biopsy methods. It has been shown to be superior to wire-frame technique by immortalizing the original shape and dimensions of the surgically excised prostate gland. Moreover, our 3-dimensional computer modeling system improves upon other systems: It is more than a simple extension of the planimetric technique, and it is able to demarcate clearly the boundaries of Gleason grades just 1 grade apart.