The microsurgical treatment of large and giant aneurysms of the internal carotid artery located parasphenoidally

Internal carotid aneurysms in the ophthalmic area presents a challenge in cerebrovascular neurosurgery. The study was undertaken to provide evidence for the application of intravascular aspiration during direct surgical interventions and to outline their variants used at the N. N. Burdenko Institute of Neurosurgery. The study included 4 (3 females and 1 male) patients with large and giant internal carotid aneurysms of parasphenoidal site who were treated at the Institute. Clipping of the aneurysmal neck was made by employing intravascular blood aspiration from the aneurysm. The technique proved to be effective in proximal monitoring the carotid artery at surgery. It substantially reduced aneurysmal blood flow and wall tension, thus favouring aneurysmal dissection to make clipping.     

The stabilization of cortical evoked potentials during selective visual attention

The event-related potentials (ERP) to lateralized moving visual stimuli (administered to the right and to the left of the subject) were recorded in six derivations in eight healthy subjects during passive viewing and selective attention to one of the stimuli (the relevant one), which demanded precise and rapid motor reaction. It was shown that during the selective voluntary attention correlation between successive ERP was substantially higher than that under conditions of passive (involuntary) attention, i.e. the ERP in the occipital, parietal, and frontal derivations during voluntary attention were more stable. The less was correlation between the ERP at passive viewing, the greater was the difference between the values of correlation coefficients during selective and passive attention. It is suggested that role of selected attention consists in stabilization of activity of the cortical structures, which are involved in solving the behavioral task.     

Internal carotid artery narrowing in children with retropharyngeal lymphadenitis and abscess

BACKGROUND AND PURPOSE: Our purpose was to describe the association between narrowing of the internal carotid artery (ICA) and retropharyngeal abscess in children. METHODS: Neck CT scans from 13 consecutive children with suppurative retropharyngeal lymphadenitis and abscess were evaluated retrospectively for asymmetric ICA diameters at the level of the abscess. Clinical status at the time of illness was established via a chart review. Twenty control CT scans obtained from pediatric patients with normal imaging findings were evaluated prospectively to determine symmetry and size of the ICA. RESULTS: Mean diameter of the normal ICA, contralateral to the retropharyngeal abscess, was 5 mm (range, 3-8 mm), while mean diameter ipsilateral to the abscess was 3 mm (range, 1-5 mm). The diameters of the normal and abnormal ICAs were statistically significantly different. All children were neurologically normal. The right and left ICAs in children with normal CT findings in the neck were symmetrical in diameter. CONCLUSION: Despite dramatic narrowing of the ICA ipsilateral to retropharyngeal lymphadenitis and abscess, no children in this series had neurologic deficits, suggesting that such narrowing is a common, benign, and, most likely, incidental imaging finding.     

0412-1961

利用前文的实验方法,本文研究铁液中Si,Nb活度的相互作用.为了使脱氧产物稳定,本文和前文不同,采用下列组装的定氧电池: Mo     

Iterative global and local methods of image restoration

Most of the reconstruction algorithms smooth out the edges of the reconstructed images but iterative total variation regularization and local adaptive methods preserve the edge information without any prior knowledge about the image geometric details. The restoration performance of the proposed algorithms for image deblurring is compared in terms of the mean squared error. Computer simulation results are provided and discussed.     

鲁棒变结构模型参考自适应控制器的分析与设计(Ⅰ)

对含有未建动态ＳＩＳＯ定常线性系统提出了一种控制增益可切换的变结构模型参考自适应控制方案。其主要结果是：解决了当对象建模部分相对阶为１、高频增益符号未知时,确保跟踪误差满足预先给定的过渡过程性能指标（超调量,过渡时间和稳态误差）的问题。     

七自由度气动人工肌肉机械手臂的设计及研究

设计了一种气动肌肉驱动的七自由度仿人机械手臂。肩部采用球绞形式,实现类人肩关节旋内／旋外、屈／伸及内收／外展三个自由度,旋转运动范围为-39．5～39．5°,屈伸运动范围为－44．5～44．5°,收展运动范围为0～35．0°。肘部和腕部均采用虎克铰形式,实现肘关节的屈／伸、旋内／旋外以及腕关节的内收／外展、屈／伸,其中肘关节旋转运动范围为～39．5～39．5°,屈伸运动范围为－60．5～32．5°;腕关节收展运动范围为～70．5～70．5°,抬伸运动范围为-39．5～39．5°。对机构进行了仿真分析,并搭建了手臂实物系统进行测试。实验结果表明,该手臂重量轻,受控性好,能够很好地实现人类关节的柔顺运动。     

磨矿回路加入重选回收柿竹园钨矿的选矿新工艺研究

柿竹园多金属矿黑、白钨矿的比例约为３：７，根据黑钨矿的矿石性质，在磨矿回路中加和重选早收已角度的单体钨矿物，有利于减轻黑钨矿过粉碎和减少黑钨细泥。小型试验、扩大试验和工业试验，在磨矿回路中获得１１．８２％￣１６．９７％的黑钨回收率，使全流程合格钨精矿的总回收率达８１．８９％￣８６．２３％。     

Mg_2Si/Al复合材料制备技术研究现状

Mg2Si/Al复合材料具有较多的优点,有着广泛的应用前景。探讨了Mg2Si/Al复合材料的制备技术,总结了各种技术的优缺点,得出了适合大规模工业化的制备方法。     

改良柱前荧光胺衍生化-高效液相色谱法测定猪肉中11种磺胺类药物残留

建立改良的磺胺类药物与荧光胺反应的衍生化方法,并应用于猪肉中11种磺胺类药物的高效液相色谱-荧光法测定.选用0.1 mol/L KH2PO4溶液(pH 3.0)0.8 mL、0.3 mg/mL荧光胺溶液0.2 mL与磺胺类药物发生衍生化反应,4℃避光反应40 min,得到磺胺-荧光胺衍生产物.该衍生化方法稳定、可靠,衍...