抗单纯疱疹病毒CHA9-3D8单链抗体三维结构的计算机模建和分析

将１株分别来自单纯疱疹病毒ＭｃＡｂ（重链）和出血热病毒ＭｃＡｂ（轻链）的杂化单链抗体基因序列，在ＳＧＩ图形工作站上，利用同源蛋白结构预测的方法，建立起了其三维结构模型，以寻找轻、重链空间结构的相互关系，观察抗体的结构及表面静电性和疏水性的变化。结果表明，杂化链抗体的轻、重链位置得当，轻链参与组成了“疏水口袋”的形成，并有约五分之二的“袋口”部分由其围成，Ｌｉｎｋｅｒ链位置贴切，游离于轻、重链之外。轻、重链的３个超变区围绕于疏水口袋附近。这一研究为进一步分析轻、重链在抗体功能中的作用，以及改造抗体并提高抗体活性等方面提供了一种途径。     

应用多层螺旋CT对耳硬化症的术前评估价值

目的:评估MDCT在术前耳硬化症诊断中的作用。方法:收集经临床证实为耳硬化症、且CT扫描采用螺旋扫描病例共18例,采集的数据传输到4.1工作站,进行多平面重建。结果:18例共36耳显示异常:单独前庭窗异常18耳,表现为前庭窗扩大或狭小,周围骨质密度降低或镫骨底板板密度增高;前庭窗及蜗窗同时受累共8耳;主要累及耳蜗周围迷路骨质10耳,表现为耳蜗骨迷路边缘不整,呈条片状密度减低或双环征。MPR交互重建充分显示了所有重要解剖结构的位置、形态:其中3耳为颈静脉球高位。结论:MDCT可以正确显示耳硬化症病灶的细微改变,提供详细的术前诊断信息;结合MPR技术可全面观察病变范围,并充分显示颞骨内重要解剖结构的位置和形态。对于手术方案的设计、防止手术并发症和提高疗效等具有重要意义。     

Information Capacity of the Corticospinal Tract Recordings as a Neural Interface

Recording the motor output of the central nervous system from the cervical spinal cord was investigated as a method of generating voluntary command signals, potentially to be used in quadriplegic individuals. Corticospinal volleys evoked by motor cortex stimulation were recorded from the spinal cord surface with multicontact electrodes in anesthetized cats. The multicontact recordings were analyzed for their information-carrying capacity as a neural interface. Neural signals resulting from the stimulation of various points in the motor cortex were considered as symbols of an alphabet that were sent through a discrete information channel. The information capacity of this channel at the thermal noise level of the electrode contacts was calculated. The maximum information rate was 1.57 bits in a trial for a 4-symbol alphabet. The background noise that reduces the information rate to 50% of its maximum theoretical value was defined as the half-bitrate-noise-tolerance (HBR-NoiseTol) and used as a measure of symbol distinguishability. The HBR-NoiseTol for all trials on average was 24 +/- 12%, 18 +/- 10%, and 15 +/- 9% for interfaces with 2-, 3-, and 4-symbol alphabets (n = 11 trials). The average peak-to-peak amplitude of the neural volleys was 13.5 +/- 6.7 microV (n = 11). These results suggest that the corticospinal signals can be recorded with spatial selectivity from the spinal cord surface and thus warrant further investigation of their potential use for a spinal cord-computer interface.     

影像导航计算机辅助手术系统中的空间数据结构模型研究

影像导航计算机辅助手术系统（ICAS）是一种为术者提供术野周围重要解剖结构信息的辅助工具，可提高手术安全性和成功率。合理的空间数据结构模型是确保ICAS实现导航功能的关键因素之一。本研究提出了组合邻接表线索化八叉树模型（MALTO），并就基本操作的可实现性和实时性，分析比较了MALTO与4种常用模型的性能。研究结果表明：MALTO不但可以实现数据查找、搜索和计算等基本操作，且具有时间效率优势。因此，MALTO是适合于ICAS的空间数据结构模型。     

DNA polymerase gene locus of <Emphasis Type="Italic">Cercopithecine herpesvirus 1</Emphasis> is a suitable target for specific and rapid identification of viral infection by PCR technology

The family Herpesviridae comprises at least 100 herpesviruses. Numerous human and animal pathogenic herpesviruses have been identified so far, including Cercopithecine herpesvirus 1 (CeHV-1). This virus is a member of the subfamily Alphaherpesvirinae and is the most hazardous herpesvirus to man. CeHV-1 is also known as B-virus or monkey B virus and as Herpesvirus simiae. In order to gain more genetic information, the viral DNA polymerase (DPOL) gene was identified using polymerase chain reaction (PCR) and DNA nucleotide sequence analysis. The deduced amino acid sequence contains the motifs and signatures that are typical for the B-family of DPOLs. The DPOL gene of CeHV-1 was found to be a suitable target for the specific and rapid identification of the Cercopithecine herpesvirus 1 infection by PCR technology. Comparative analysis of the DNA sequences of the DPOL gene loci of CeHV-1, Human herpesvirus 1 and 2 (HHV-1 and HHV-2), and other herpesviruses was carried out for determination of unique genomic regions of the individual DPOL genes. A primer set of 12 primers was used for screening the DNA of CeHV-1, HHV-1, and HHV-2 by detailed PCR. It was found that six out of twelve primer combinations are able to detect specifically the CeHV-1 genome without cross reactivity with the genome of HHV-1 and/or HHV-2. The specificity of the individual amplified DNA fragments was confirmed by DNA nucleotide sequence analysis. The results of these studies indicate that the six primer combinations of the specific CeHV-1 DPOL primer set is the method of choice for a rapid, precise and specific identification of a CeHV-1 infection by PCR. Due to the fact that this specific CeHV-1 DPOL primer set does not amplify any DNAs of HHV-1 or HHV-2 genome this technology is stressing and can be successfully used unlimited and more credible in all laboratories with PCR technical facility routinely for detection of a CeHV-1 infection in vivo or in vitro.The GenBank Accession No. of the sequence of DNA polymerase gene of Cercopithecine herpesvirus 1 (CeHV-1) reported in this study is AY568415, DPOL protein ID AAT67222; nuclear phosphoprotein ID AAT67223     

200MHz的H面号角环形相控阵系统热疗深部肿瘤的研究

本文提出并研究了一种新型的电磁热疗系统-H面号角环形相控阵系统。推导出了适应性广的理论公式。以肺部CT图为模型,用矩量法计算得到了胸腔横断面内电场分布及吸收功率分布的计算机数值结果。结果表明,在200MHz的电磁波辐射下,适当调节阵列各单元的相位,振幅和位置,肺部肿瘤可得到优化的选择性加热,从而达到最佳的热疗效果。     

A polyexponential deconvolution method. Evaluation of the “gastrointestinal bioavailability” and meanin vivo dissolution time of some ibuprofen dosage forms

A new deconvolution algorithm (DCON) suitable for pharmacokinetic applications is presented. It requires that both the impulse and input responses, typically systemic drug levels, be well described by polyexponential equations. DCON has a wider range of applications than an earlier method (DECONV) from which it is derived. A FORTRAN program is provided, making implementation of the technique a simple matter. DCON is demonstrated to evaluate the GI bioavailability, defined as the rate and the extent of gastrointestinal drug release, of various ibuprofen dosage forms. The GI drug release kinetics exemplifies a pharmacokinetic system which cannot be evaluated using the previous deconvolution algorithm (DECONV) because of an initial zero drug level response. This limitation is not found in DCON. It is also demonstrated how the mean in vivo dissolution time MDT can be evaluated by deconvolution.     

登革热数学模型及其应用研究（Ⅱ）——利用数学模型评价不同措施对登革热的防治效应

利用我们建立的登革热数学模型,通过计算机对5种不同的防治措施和不同时间采取措施控制登革热流行的效应进行了模拟评价。结果显示,室内滞留喷洒对控制登革热的流行最为有效;清除孳生场所有一定效果,但视清除孳生场所的程度而定;而同时采用清除孳生场所和使用蚊帐防护的措施可收到较好的防治效果,而且费用可能较低;超低容量喷洒效果较差。模拟结果表明,同一种措施,即使只提前10天实施,效果也好得多。模拟还表明,在人群中,如果70％以上的人具有特异性免疫力,即可有效地阻止同型登革病毒的输入和流行。上述模拟结果将为现场流行病学工作提供有价值的参考,同时也显示了疾病数学模型的实际应用价值。     

影像学检查在食管癌诊断中的临床应用

目的 :探讨螺旋 CT对食管癌诊断的应用价值。方法 :15例食管癌患者行螺旋 CT增强扫描后多平面重建和 CT仿真内窥镜成像 ,并与其传统 CT轴位图像、X线钡餐造影结果对比。结果 :115例食管癌螺旋 CT增强扫描的轴位图像与传统 CT图像几乎完全相同 ,可以观察病变大小、部位、形态、外周浸润范围和淋巴结转移等情况。 2多平面重建可在不同方位以最佳角度对食管肿瘤进行观察。 15例食管癌 CT仿真内窥镜成像可从头侧或足侧观察食管壁和腔内病变形态 ,获得类似纤维食管胃镜的结果。3X线食管钡餐造影能较好地显示管腔粘膜的改变及癌瘤的长度 ,是普查的重要方法。结论 :螺旋 CT图像较传统 CT图像及 X线钡餐造影为食管癌的术前分期诊断提供了更全面的信息 ,CT仿真内窥镜成像是纤维食管内窥镜的重要补充。     

颌骨肿瘤的X线、二维及三维CT影像对比研究

[目的]对比研究常规X线、二维CT和三维CT对颌骨肿瘤显示的优缺点。[方法]对51例颌骨肿瘤患者行常规X线、二维CT和三维CT检查,比较分析三种检查方法对颌骨肿瘤晃示的特征,并与手术病理结果相对照。[结果]对下颌骨肿瘤三种检查方法均能有交地显示,以三维CT显示得最为直观明了。对上颌骨肿瘤,三维CT通过旋转与切割,能够立体直观地显示肿瘤的部位、大小、形状及毗邻关系,尤其对腭板、眶下壁以及颅底骨质破坏的显示更具成越性;二维CT对肿瘤的囊性或实性改变、肿瘤的软组织成份以及颅内受侵情况的显示最为有利;常规X线对肿瘤区牙根周围的改变显示得最为清楚。[结论]常规X线、二维CT和三维CT对颌骨肿瘤的显示各有优缺点,三者结合能提高肿瘤显示的准确性,对颌骨肿瘤的诊断和治疗具有重要作用。