Variability of biochemical gene markers in residents of the city of Tomsk

Variation of seven biochemical gene markers (Tf, Gc, Hp, ACP1, PGM1, PGD, and EsD) in the population of Tomsk was examined. The genetic structure of this population is compared to that of other urban populations from different regions of Russia.     

海湾战争中C~3I的经验、问题及战后动态

本文首先从海湾战争中C~3I系统的层次结构谈起,进而论述了交战双方C~3I系统的成功经验与存在问题,并且重点研究了战后外军C~3I的发展动态、设备改进、政策调整等各方面情况。     

回转窑轴向下滑的接触力学问题

通过对接触区的应力、应变分析，推导出回转窑轴向下滑的计算公式，用接触力学方法解释了回转窑下滑现象。利用所推导的公式能够对回转窑轴向运动速度进行定量计算。     

小型铝厂电解槽用螺旋压紧式圆盘卡具的设计

本文详细设计了一种新型的螺旋压紧式圆盘卡具的设计及其特点。     

Effects of single oral administrations of haloperidol and d-amphetamine on prepulse inhibition of the acoustic startle reflex in healthy male volunteers

The effects of acute administration of an indirect dopamine-agonist, d-amphetamine, and a non-selective dopamine receptor antagonist, haloperidol, were investigated in normal male volunteers on habituation and prepulse inhibition (PPI) of the acoustic startle reflex in two experiments. In Experiment 1, 40 male non-smoker volunteers were tested for habituation and PPI (defined as percentage reduction of the pulse-alone amplitude; prepulses 9 dB above background) before and after double-blind administration of either 2 mg haloperidol or placebo. No influence of haloperidol was observed on either habituation or PPI of the startle reflex in this experiment. In Experiment 2, 60 male volunteers underwent startle testing before and after double-blind administration of a single oral dose of 5 mg haloperidol, 5 mg d-amphetamine or placebo. Habituation and PPI (prepulses 15 dB above background) for the placebo group did not differ significantly from that observed for the d-amphetamine or for the haloperidol group. However, in a subgroup of smoking subjects, both d-amphetamine and haloperidol reduced PPI as compared to that observed prior to drug administration. The implications of these findings in relation to animal pharmacological studies and observed sensorimotor gating deficits in schizophrenia are discussed.     

Long-range fragmentation of the eukaryotic genome by exogenous and endogenous nucleases proceeds in a specific fashion via preferential DNA cleavage at matrix attachment sites

Small cell lung cancer cells (OC-NYH-VM) were permeabilized and treated with different nucleases. The long-range distribution of DNA cleavage sites in the amplified c-myc gene locus was then analyzed by pulsed field gel electrophoretic separation of the released 50-kilobase to 1-megabase DNA fragments followed by indirect end labeling. Exogenous DNase I and nucleases specific for the single-stranded DNA were found to generate similar nonrandom patterns of large DNA fragments. The cleavage sites were located close to or even colocalized with matrix attachment regions, which were mapped independently using a recently developed procedure for DNA loop excision by DNA topoisomerase II-mediated DNA cleavage. Endogenous acidic nuclease with the properties of DNase II also digested DNA preferentially in proximity to the matrix attachment regions, generating characteristic patterns of excised DNA loops and their oligomers. A similar, although less specific, pattern of DNA fragmentation was observed after incubation of permeabilized cells under conditions favoring the activity of endogenous neutral Ca(2+)- and Mg(2+)-dependent nucleases. These findings are discussed in the context of the current model of the spatial domain organization of eukaryotic genome.     

Gender differences in prospectively versus retrospectively assessed smoking withdrawal symptoms

Investigations of gender differences in the frequency and/or intensity of smoking withdrawal symptomatology have yielded conflicting findings. Several studies using measures collected both before abstinence and at the peak of symptomatology have failed to find gender differences. Yet, when asked to rate symptomatology experienced during past quit attempts, women have repeatedly been shown to endorse significantly more symptomatology than men. A possible explanation is that, although men and women show no differences when rating symptoms prospectively, women remember their past withdrawal symptoms as being more severe than do men, either because women exaggerate the difficulties they experience or because men downplay them. To test this hypothesis, and to determine whether men or women were more accurate in their recollections, we combined data from two studies in which subjects were asked to assess symptoms prospectively following 2 days of abstinence, and also to rate withdrawal during past quit attempts. As predicted, we found the effects of abstinence to be similar when assessed prospectively but different when assessed retrospectively, with women reporting more symptomatology than men. Men whose retrospective and prospective responses were discordant consistently underestimated the likelihood of experiencing symptomatology; women showed no consistent trends. The total number of symptoms reported retrospectively by women was similar to the total number reported prospectively, whereas men significantly underestimated the number of symptoms that they actually experienced. These findings may suggest ways in which treatment strategies can be tailored to the differences between male and female styles in recalling past experiences with abstinence from smoking.     

移动通信卫星系统展望

本文阐述了移动通信卫星系统的发展趋势,包括增强同步轨道卫星的功能,发展同步轨道卫星与非同步轨道卫星的组合系统,采用低轨道卫星系统,并对光学星间链路低轨道卫星系统的概念进行了简单介绍。     

非阻塞分组交换网络的系统模型与性能分析

本文建立了具有输入与输出缓冲器非阻塞分组交换网络的排队模型,得出了平均排队长度、平均等待时间和饱和吞吐量的结果,指出可通过增加交换容量和降低先进先出的排队规则的限制来提高分组交换的吞吐量,最后提出了一种限制交换容量具有重复竞争机制的改进方案,对分组丢失概率进行了定量分析。从而确定了该结构的指标体系。     

C~3I文电传输系统仿真技术研究

针对C~3I文电传输对通信网的特殊要求,文章重点对文电传输到达模式、服务过程、排队规则与系统排队建模等关键技术进行了研究,并对系统仿真程序工作流程提出了具体设计建议。文章可对C~3I通信网技术总体设计与方案论证提供参考。