使用eCCI仪制备大鼠TBI动物模型及血清S100B和NSE含量变化

目的 为科学研究提供重复性好、损伤（TBI）程度稳定的颅脑损伤（TBI）动物模型制备方法.方法 选用SD大鼠,随机分为正常A组、模型B组、模型C组、模型D组和假手术E组.使用电子颅脑损伤仪（eCCI）,选定不同打击参数分别对模型B组、模型C组、模型D组打击造模,制备不同损伤程度的TBI模型,通过观察血清S100B和NSE含量变化评价模型制备效果.结果 损伤发生后第1天、第2天、第3天血清S100B和NSE含量均呈上升趋势,模型组与假手术组比较均有显著性差异（P＜0.01）;各模型组之间表现为随打击力度的增加,S100B和NSE含量显著性增高（P＜0.01）.结论 利用eCCI仪制备TBI大鼠模型,能够通过打击速度、打击深度参数的设置而精确控制模型的损伤程度,具有易操作、打击强度可控制、重复性好等优点,能够根据研究需要制备各种理想损伤程度的动物模型.     

主成分回归对脑卒中发病与环境因素间关系的解析

脑卒中的诱发已经被证实与环境因素包括气温和湿度之间存在密切关系.对脑卒中的发病环境因素进行分析可以对脑卒中高危人群进行风险评估并及时采取干预措施,而平均气压、最高气压、最低气压、平均温度、最高温度、最低温度、平均相对湿度、最低相对湿度8个自变量之间的共线性使得用多元线性回归方法得到的回归方程的精度降低.运用主成分回归分析,对脑卒中发病人数与环境因素进行了深入解析,结合统计软件SPSS的分析结果,给出了计算主成分的正确表达式,并将主成分与发病人数进行多元线性回归,最终确定了脑卒中发病人数与8个环境因素间的数学模型.     

南方鲶脑和脑神经的观察

对南方鲶脑的外部形态和内部结构及脑神经特点进行了描述.与一般鲤科鱼类的脑比较其不同点在于:端脑发达,体积比视叶大;小脑特别发达,向前盖住中脑、间脑和部分端脑,后部向两侧扩展成耳状叶;间脑有明显的中间叶、球状核,视交叉紧靠间脑前方,脑下垂体在二下叶之间,远离视神经交叉.并具有特别的副侧线神经、侧线神经侧腹支及电觉初级中枢.靠味觉和嗅觉共同摄取食物.     

数字人图像的自动分割方法

为克服现有方法对数字人切片图像分割中人工参与的依赖,提出了一种基于连通域标记和K-均值聚类的数字人脑彩色切片图像分割方法.该方法首先通过连通域标记分割出脑组织的初始区域,再通过腐蚀操作精确提取脑组织,然后在RGB(红绿蓝)空间内借助直方图确定聚类中心,以欧几里得距离为判断标准实现对白质的K-均值聚类分割.采用首例中国女...     

大鼠颅脑冷冻伤后一氧化氮的变化及其对脑水肿的影响

目的：探讨脑冷冻性损伤后一氧化氮(NO)与脑水肿的关系及其对脑水肿的影响。方法：建立大鼠脑冷冻伤脑水肿模型，测定伤后伤侧脑组织水的质量分数和颈静脉血NO量，并应用一氧化氮合酶(NOS)抑制剂进行治疗。结果：伤后伤侧颈静脉血NO浓度增加，但随着脑水肿的加重，NO浓度呈进行性下降。应用NOS抑制剂可以有效减少脑组织水的质量分数。结论：NO与创伤性脑水肿的发生和发展密切相关，NOS抑制剂也许可以用于治疗脑水肿。     

滞育和非滞育棉铃虫脑的组织解剖学研究

滞育和非滞育棉铃虫在不同的发育阶段，脑的形态组织学结构存在着一定的差异，主要表现在：非滞育脑的神经纤维体发达，神经分泌细胞中的核较大，且细胞质中除了有线粒体外，还有大量的粗面内质网及游离的核糖体；而滞育脑的神经纤维体相对固缩、不发达，神经分泌细胞中核较小，细胞质中含有线粒体、光滑内质网和特有的脂滴，不具粗面内质网．这些证据表明滞育棉铃虫的脑活性相对较低．     

神经元建模和脑功能成像的研究

长期以来，在理论上架建神经生理学和心理学之间的桥梁一直是神经科学家和认知科学家的研究方向和发展目标。根据电生理学的数据、神经生理学实验和神经心理学证据，本文建立了一种生物神经元的合理数学模型。该神经元模型构造的神经网络的动力学行为可以联系到一些神经生理现象和心理现象。本文还讨论了神经元建模、脑功能和功能成像三者之间的交叉问题。     

Molecular mechanisms of glutamate-dependent neurodegeneration in ischemia and traumatic brain injury

Stroke and neurotrauma mediate neuronal death through a series of events that involve multiple interdependent molecular pathways. It has been suggested that these pathways are triggered following elevations in extracellular excitatory amino acids, primarily glutamate [1]. This report outlines mechanisms involving glutamate-mediated excitotoxicity with specific focus on (i) the role of Ca²⁺ in neurotoxicity, (ii) The concept of source specificity of neurotoxicity, (iii) the role of the ionotropic N-methyl-D-aspartate (NMDA)-subtype glutamate receptor and its associated submembrane molecules that may give rise to signaling specificity in excitotoxicity and (iv) the role of glutamate-mediated free-radical generation and associated cell death pathways. We also highlight a novel, peptide-based approach for uncoupling NMDA receptors from excitotoxicity in the rat central nervous system subjected to focal ischemia, thereby reducing stroke infarct volume and improving neurological functioning.Received 11 August 2003; received after revision 15 September 2003; accepted 17 September 2003     

Identification of the bioactive peptide PEC-60 in brain

PEC-60 is a 60-residue peptide originally isolated from pig intestine. It inhibits glucose-induced insulin secretion from perfused pancreas in a hormonal manner and also has biological activity in the immune system. PEC-60-like immunoreactive material has been reported in catecholamine neurons of the central and peripheral nervous systems, but the peptide has not been identified from that material. We have now isolated PEC-60 from pig and rat brains with a method that combines column purification procedures with the specificity of a radioimmunoassay and the sensitivity of mass spectrometry to directly identify the peptide. The results show that PEC-60, like many other peptides, is expressed in the gastrointestinal tract and the central nervous system. The specific regional brain distribution and interaction with classical neurotransmitters raise the possibility that PEC-60may play a role in the central nervous system disorders involving dopamine dysregulation. Received 6 December 2002; received after revision 10 December 2002; accepted 11 December 2002 RID="*" ID="*"Corresponding author.     

Chinese semantic processing cerebral areas

This study has identified the active cerebral areas of normal Chinese that are associated with Chinese semantic processing using functional brain imaging. According to the traditional cognitive theory, semantic processing is not particularly associated with or affected by input modality. The functional brain imaging experiments were conducted to identify the common active areas of two modalities when subjects perform Chinese semantic tasks through reading and listening respectively. The result has shown that the common active areas include left inferior frontal gyrus (BA 44/45), left posterior inferior temporal gyrus (BA37); the joint area of inferior parietal Iobules (BA40) and superior temporal gyrus, the ventral occipital areas and cerebella of both hemispheres. It gives important clue to further discerning the roles of different cerebral areas in Chinese semantic processing.