程控交换机集中维护管理系统的设计与实现

本文从工程设计角度描述了程控交换机集中维护管理系统的硬件构成、软件功能，对于同类系统的设计和实现具有一定的参考价值。     

Novell网站点间实时通信的实现与应用

在局域网环境中，一般使用文件服务器中的文件来传送数据，由于效率低、实时性差，应用范围受到一定限制。本文从提高通信的实时性出发，就采用ＩＰＸ协议实现点对点诉有关技术进行了讨论，并介绍了该项技术的应用实例。     

Feasibility of gymnodimine and 13-desmethyl C spirolide detection by fluorescence polarization using a receptor-based assay in shellfish matrixes

The detection of toxins in shellfish through reliable methods is essential for human health preservation and prevention of economic losses in the aquaculture industry. Although no human intoxication has been unequivocally linked to gymnodimines or spirolides, these phycotoxins are highly toxic by intraperitoneal injection causing false positives in lipophilic toxin detection by the mouse bioassay. Based on the detection of molecular interactions by fluorescence polarization an inhibition assay was developed using fluorescent α-bungarotoxin and nicotinic acetylcholine receptor-enriched membranes of Torpedo marmorata to detect gymnodimine and 13-desmethyl C spirolide. Both toxins, classified into the cyclic imine group, inhibit the interaction of α-bungarotoxin with Torpedo nicotinic acetylcholine receptors in the nM range. In this study we analyze the matrix effect of four shellfish species on the fluorescence polarization assay. Mussels, clams, cockles and scallops were extracted with acetone and sequentially partitioned with n-hexane and chloroform. The interference of these shellfish extracts with the α-bungarotoxin fluorescence or its binding to the nicotinic acetylcholine receptor was lower than 11%. The average recovery rates of gymnodimine and 13-desmethyl C spirolide using these solvents were 90.6 ± 7.8% and 89.6 ± 3.2%, respectively with variations among species. The quantification range of this fluorescence polarization assay for gymnodimine and 13-desmethyl C spirolide in all tested species was 80-2000 μg kg⁻¹ and 85-700 μg kg⁻¹ of shellfish meat, respectively. This assay format can be used to detect gymnodimine and 13-desmethyl C spirolide in shellfish as a screening assay.