Global attraction and stability for Cohen–Grossberg neural networks with delays

We consider a class of Cohen–Grossberg neural networks with delays. We prove the existence and global asymptotic stability of an equilibrium point and estimate the region of existence. Furthermore, we show that the trajectories of the neural networks with positive initial data will stay in the positive region if the amplification function satisfies a divergent condition. We also establish the existence of a globally attracting compact set for more general networks. We estimate this compact set explicitly in terms of the network parameters from physiological and biological models. Our results can be applied to neural networks with a wide range of activation functions which are neither bounded nor globally Lipschitz continuous such as the Lotka–Volterra model. We also give some examples and simulations.     

牙槽裂植骨改善唇腭裂患者鼻底塌陷畸形

分析唇腭裂患者牙槽裂植骨与改善鼻底塌陷畸形的关系。方法：对同一术者所行牙槽裂植骨术的单侧唇腭裂患者48例进行临床研究，结合X线片及面部正侧位照片探讨植骨成功与否与鼻底塌陷畸形改善的关系。结果：植骨成功组的患侧鼻底塌陷畸形的改善较未成功组有明显差异，明显高于未成功组。结论：牙槽裂植骨成功后患侧鼻底塌陷畸形可以得到明显改善。     

BDNF基因修饰神经干细胞移植后大鼠脊髓损伤移植处的基因表达变化

目的：了解脑源性神经营养因子（Brain-derived neurotrophic factor,BDNF）基因修饰神经干细胞移植到大鼠脊髓损伤处后的基因表达变化，为脊髓损伤修复提供基础研究资料。方法：大鼠随机分为4组：正常对照组，手术对照组，神经干细胞（Neural stem cells,NSCs）移植组，BDNF－NSCs移植组，各组分4个时相点（7d、1个月、2个月、3个月），利用细胞移植、X-gal组化、免疫组化、原位杂交等方法，观察了移植处细胞的标记基因（LacZ）表达和BDNF、胶质纤维酸性蛋白（GFAP）、神经丝－200（NF－200）的表达。结果：大鼠脊髓损伤移植处细胞中，有标记基因阳性细胞，BDNF强烈表达，尤其是BDNF－NSCs移植组的移植后1周和1个月时。各组各时相点均有GFAP和NF－200免疫反应阳性细胞和纤维。结论：BDNF基因修饰神经干细胞能在脊髓损伤移植处存活，强烈表达BDNF，BDNF基因修饰神经干细胞可以作为脊髓损伤修复的移植材料。     

肘关节后脱位伴桡骨头和尺骨冠突骨折 (恐怖三联征)5例初步报告

[目的]介绍"肘关节恐怖三联征"的概念(肘关节后脱位同时伴有桡骨头和尺骨冠突骨折),并报告5例患者的临床治疗体会。[方法]自2004年4月～2007年3月,作者共收治肘关节三联征损伤5例。桡骨头骨折按Mason法分类:Ⅱ型4例,Ⅲ型1例;按Schatzker法分类:Ⅰ型1例,Ⅱ型3例,Ⅲ型1例。尺骨冠突骨折按Regan-Morrey法分类:Ⅰ型1例,Ⅱ型4例;按O′Driscoll法分类:5例均为Ⅰ型。4例采取了手术内固定治疗,以3 mm钛空心拉力螺钉或1 mm K针分别固定冠突和桡骨头,并缝合修复肘内外侧副韧带。术后屈肘90°前臂旋转中立位石膏外固定3周,开始屈伸和旋转康复训练。[结果]4例手术治疗的患者经3个月～3年随访,骨折愈合,肘关节稳定,无疼痛。肘关节屈伸幅度平均120°,前臂旋转幅度平均110°。3例随访1年以上,Mayo肘关节功能评分:优2例,良1例。未手术治疗的1例功能评定为差,有肘关节不稳定和疼痛。[结论]肘关节恐怖三联征的骨折片虽然很小,但伴有肘内外侧副韧带撕裂,肘关节严重不稳定。只有在重建了骨关节和软组织结构稳定的基础上,及早(3周内)进行康复锻炼,才能获得较好的功能恢复。     

基于GMDH型神经网络的EEG分类研究

为了提高对不同认知状态下脑电信号(EEG)的分类正确率，提出一种GMDH型神经网络及改进的训练算法。此网络结构在演化中生成，分类规则由简单多项式表示，训练算法可防止出现过拟合。此网络用于区分算术运算和休息状态下的脑电信号，正确率达到84．5％，与标准前向型神经网络(FNN)比较，显示了较好的分类效果。     

以桡动脉为移植体行冠状动脉旁路术的局解手术学研究

本文对104侧上肢桡动脉第一段和63例成人离体心脏之冠状动脉及其主要分支,根据临床应用进行了观测。结果:桡动脉长度为22.10±1.2cm;外径(下同):上端为3.00±0.6mm,下端为2.60±0.6mm。后降支(房室交点下1cm处)为2.41±0.4mm,左右心耳与肺劝脉交角下1cm处的前降支为3.83±0.6mm,右冠状动脉主干为3.79±0.7m。距离:自主动脉前窦上2cm至前降支中点的长度为6.61±0.5cm,经右冠状沟至房室交点的长度为11.80±1.5cm。测量数据提示:以桡动脉为移植体足以吻接任何冠状动脉。本文尚阐述和讨论了该术式的局解手术学基础和操作程序,对冠状动脉旁路术(CABO)中常用的几种移植体之利弊进行了评     

Neurokinin A with K channel blockade potentiates contraction to electrical stimulation in human bronchus

This study investigated the effects of neurokinin A (NKA) on cholinergic neural responses in human bronchus. NKA (0.1 nM) did not alter the contractile response to submaximal electrical field stimulation. However, K⁺ channel blockade with 4-aminopyridine (4-AP) (0.1 mM) potentiated the response to electrical field stimulation (to 182 ± 25% of control, n = 4, P < 0.05) and subsequent addition of NKA in the presence of 4-AP produced further potentiation (to 123 ± 6% of the response to 4-AP n = 4, P < 0.05). Neither 4-AP (0.01 or 0.1 mM) nor NKA in the presence of 4-AP potentiated the actions of exogenous acetylcholine but in these experiments 4-AP itself produced a marked direct contractile response. Thus NKA in the presence of K⁺ channel blockade potentiates cholinergic neural response in human bronchus and this occurs at a prejunctional site.     

冠脉旁路移植术中桡动脉的获取和应用

目的总结冠状动脉旁路移植术中桡动脉的获取方法和早期临床效果。方法22例冠状动脉旁路移植术患者,行量化Allen试验决定是否切取桡动脉。桡动脉伴随静脉一起切取,术中不直接接触桡动脉,严格避免夹镊桡动脉本身;离断后腔内注入肝素罂粟碱液,并将桡动脉置于该液中备用。共获取桡动脉22根,远端吻合至冠状动脉后降支、钝缘支及前降支,近端均吻合至主动脉。术后常规应用钙通道阻滞剂12个月。结果术后患者心绞痛消失,心功能显著改善,无围术期心肌梗死。无术中桡动脉痉挛现象,围术期无出血、栓塞合并症,无手臂缺血发生。结论桡动脉移植物可常规应用于冠状动脉旁路移植术;严格的“免触”技术和术后应用钙通道阻滞剂是保证桡动脉良好功能的关键。     

重组毕赤酵母表达期菌体浓度的软测量模型

建立了用于在线估计高密度重组毕赤酵母培养过程中处于表达阶段的菌体密度软测量模型。分别对比了基于遗传算法（GA）的动力学软测量模型以及基于人工神经网络（ANN）的软测量模型，并对神经网络软测量模型的拓扑结构以及训练参数进行了初步探讨。当采用基于遗传算法（GA）的动力学模型，模型拟舍值的最大误差为7．63％；在采用神经网络软测量技术时，选取合适的模型结构和输入参数，最大误差为3．12％，而且软测量模型可以很好地反映菌体浓度实时变化趋势。该研究结果表明，在酵母细胞的高密度培养过程中采用基于神经网络的软测量模型具有较高的准确度，可以较好地实时反映发酵过程中菌体浓度的变化。     

Information Fusing Recognition of Traditional Chinese Medicine （TCM） Pulse State Based on Stochastic Fuzzy Neural Network

Based on the fuzzy characteristic of the pulse state and syndromes differentiation thinking mode of TCM, an information fusing recognition method of pulse states based on SFNN （Stochastic Fuzzy Neural Network） is presented in this paper. With the learning ability in parameters and structure, SFNN fuses the measurement information of three pulse-state sensors distributed in Cun, Guan, and Chi location of body for the pulse state recognition. The experimental results show that the percentage of correct recognition with new method is higher than that by single-data recognition one, with fewer off-line train numbers.