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101.
BACKGROUND: The traditional neurotransmitter catecholamine and the neuropeptide tyrosine in sympathetic airway nerves have been proposed to be involved in the pathogenesis of airway diseases. OBJECTIVE: The aim of the present study was to investigate the effect of allergic airway inflammation on the expression of catecholamine enzyme tyrosine hydroxylase (TH), neuropeptide tyrosine (NPY) and tachykinins in mouse sympathetic airway ganglia. METHODS: Using neuronal tracing in combination with immunohistochemistry, the present study was designed to characterize TH, NPY and tachykinin profiles of superior cervical (SCG) and stellate ganglia after allergen challenge. RESULTS: The vast majority of fast blue-labelled SCG neurons (allergen: 97.5+/-1.22% (mean+/-SEM) vs. controls: 94.5+/-1.48%, P=0.18) and stellate neurons (allergen: 95.3+/-1.01% vs. controls: 93.6+/-1.33%, P=0.34) were immunoreactive for TH. Of the TH immunoreactive and fast blue-labelled SCG neurons, 52.0+/-1.01% allergen vs. 51.2+/-3.58% controls (P=0.83) and stellate neurons, 57.3%+/-0.97 allergen vs. 56.4+/-1.65% controls (P=0.64) were positive for TH only but not NPY, whereas 45.3+/-1.05% allergen vs. 43.3+/-1.18% controls (P=0.47) of fast blue-labelled SCG neurons and 37.9+/-0.86% allergen vs. 37.1+/-1.24% controls (P=0.62) of fast blue-labelled stellate neurons were immunoreactive for both TH and NPY immunoreactivities. There was a trend of an increase, but not significant one, in the percentage of TH-/NPY-immunoreactive and fast blue-labelled neurons in allergen-treated animals in comparison with the controls. Tachykinins, however, were not expressed by sympathetic neurons and were also not induced in sympathetic neurons after allergen challenge. CONCLUSION: The present study indicates that allergic airway inflammation does not alter the expression of noradrenalin and NPY in sympathetic ganglia and also shows that sympathetic neurons do not respond to allergic airway inflammation with tachykinins induction. However, a participation of catecholamine and NPY in the pathogenesis of allergic airway inflammation cannot be excluded in the present study as a higher neurotransmitter output per neuron following allergen challenge could be possible.  相似文献   
102.
壳聚糖作为中枢神经系统支架材料的可行性研究   总被引:2,自引:0,他引:2  
目的探索壳聚糖作为中枢神经系统组织工程支架材料的可行性。方法选择孕14~16dWistar大鼠剖宫取胎鼠脑进行分离、培养,经巢蛋白、胶原纤维酸性蛋白、特异性烯醇化酶和半乳糖脑苷酯免疫细胞化学染色鉴定获得神经干细胞,种植于壳聚糖膜和明胶膜表面培养,然后行巢蛋白免疫细胞化学染色,观察神经干细胞在壳聚糖膜和明胶膜表面的贴附、生长和分化状态,以及壳聚糖、明胶的降解速度。结果从胎鼠大脑分离获得的神经干细胞,巢蛋白染色呈阳性反应,可分化形成神经元和胶质细胞,分化细胞分别呈胶原纤维酸性蛋白、特异性烯醇化酶和半乳糖脑苷酯染色阳性反应。神经干细胞接种后12h即贴附于壳聚糖膜表面,24h壳聚糖膜和明胶膜均贴附牢固;48h明胶膜表面神经球周围首先出现带突起的分化细胞,壳聚糖膜迟至生长第3天才出现。神经干细胞接种生长后第3天,壳聚糖膜部分降解,明胶膜完全降解;第4天膜表面长满分化细胞;第5、6天壳聚糖膜大部分降解,分化细胞部分死亡。结论壳聚糖与神经干细胞生物相容,具有促细胞贴附和分化作用,由于机械性能差,不宜作为中枢神经组织工程的结构性生物支架材料,但可以单独或者联合促贴附物明胶作为促神经干细胞贴附和分化的支架表面修饰剂。  相似文献   
103.
Reported are two cases of video-PSG captured head-rolling occurring, in the context of REM Sleep Behavior Disorder (RBD) episodes, in two patients affected with idiopathic RBD and without past personal or familiar history of Rhythmic Movement Disorder during sleep. It has been speculated that the activation of neuronal pathways which underlie REM-related loss of motor control in RBD, may involve the Central Pattern Generator neuronal networks leading to the induction of Rhythmic Movements during RBD episodes, thereby allowing the re-emergence, in pathological conditions in later life, of a motor behavior typically seen in the early stage of life.  相似文献   
104.
s teaching was also significantly higher in the study group than in the control group(97.37% vs.64.71%,P<0.05).Conclusion Micro-teaching can effectively improve the quality of clinical teaching.  相似文献   
105.
目的探讨神经导航下锁孔开颅显微手术切除脑深部海绵状血管瘤的技巧及疗效。方法对15例脑深部海绵状血管病人在神经导航下行锁孔开颅,运用显微神经外科技术切除病灶。结果本组脑深部海绵状血管瘤均取得了显微镜下全切除。术中出血少,均未输血。病人术后恢复良好,无手术死亡。结论采用神经导航技术可精确定位脑深部病变,锁孔手术又是处理颅内病变的微创神经外科技术。正确应用这两项技术,结合熟练的显微神经外科技巧,可明显提高脑深部海绵状血管瘤的临床治疗效果。  相似文献   
106.
目的通过测定开颅术后周围静脉血、皮下引流液及脑脊液中药物浓度,来评价开颅手术对脑脊液药物浓度的影响.方法开颅手术前半小时静脉滴注硫酸庆大霉素8万单位,6小时后分别测定周围静脉血、皮下引流液及脑脊液中庆大霉素浓度,分别对无需切开硬脑膜及需要切开硬脑膜的病例各20例进行对照观察.结果硬脑膜完整组:周围静脉血为0.47±0.15,皮下引流液为1.41±0.46,脑脊液0.27±0.18,以皮下引流液中浓度最高,周围静脉血其次,脑脊液最低,三者比较均有显著差异(P<0.01);硬脑膜开放组:周围静脉血为0.56±0.19,皮下引流液为1.28±0.75,脑脊液为0.52±0.15,亦是皮下引流液中浓度最高,但周围静脉血与脑脊液无显著差异(P>0.05).两组之间周围静脉血以及皮下引流液无显著差异(P>0.05),而脑脊液有显著差异(P<0.01).结论开颅术后的皮下引流液中含有较高的药物浓度,与脑脊液间存在着明显的浓度差,药物能通过脑脊液与皮下渗出液的交换而进入颅内,使脑脊液中的药物浓度上升.  相似文献   
107.
Despite the fact that both H-2K and D molecules are up-regulated in the central nervous system (CNS) following Theiler's murine encephalomyelitis virus (TMEV) infection, resistance in this virus model of multiple sclerosis maps exclusively to D. To address this paradox, we examined the ability of the K and D molecules to present viral antigens to cytotoxic T lymphocytes (CTL). Whereas no virus-specific CTL were detected in the CNS of susceptible B10.Q and B10.S mice 7 days post-infection, D-restricted CTL were identified readily in the CNS of resistant B10 animals. There was no evidence of K-restricted CTL in the CNS of B10 mice at day 7 post-infection. The presence of both K- and D-restricted virus-specific CTL in the spleen of immunized B10 mice demonstrates that the exclusive use of D molecules by CTL in the CNS of mice 7 days post-infection is not due to the inability of the K molecules to present viral peptides to lymphocytes. We conclude that the prominent role of the D locus in determining resistance or susceptibility to TMEV-induced demyelination is determined by factors governing the regulation of the immune response, and not by the presence or absence of CTL precursors capable of recognizing viral peptides presented by the K and D antigen-presenting molecules, or by differences in the ability of the K and D molecules to present viral peptides.  相似文献   
108.
The aim of the current study was the introduction and standardization of two experimental conditions for dynamic pupillometry. Pupillometry is a method that can provide valuable data concerning the functioning of the autonomous nervous system. The system for recording the pupil reaction was developed in the Laboratory of Clinical Neurophysiology of the 1st Department of Neurology of Aristotle University of Thessaloniki, in co‐operation with the Laboratory of Fluid Mechanics of the Aristotle University of Thessaloniki. This system is fully automated. It includes an infra‐red video camera, which has the capacity to record in complete darkness, and an SLE (clinical photic stimulator) lamp. A software application automatically performed all the procedures. During the first experiment, one flash was administered. During the second experiment, a series of 25 flashes (1 Hz frequency) was administered. Fifty physically and mentally healthy subjects aged 23–48 years took part in the study. Means, standard deviations and ranges for all variables characterizing normal subjects during both experimental conditions are reported. Test/re‐test results and comparisons of the two eyes are also reported. The combined use of these two experimental conditions in dynamic pupillometry may be a very useful tool in medical research. There are already reports on the usefulness of pupillometry in the research of various diseases, including depression and Alzheimer’s disease. It is expected that it will also be a valuable research tool in the study of diabetes, alcoholism, myasthenia gravis, cancer, multiple sclerosis, etc.  相似文献   
109.
Spinal cord/brainstem preparations from 5- to 8-day-old rats, maintained in vitro, were used to determine the cells of origin and regions of termination of fibers in the superficial ventrolateral funiculus (VLF) at a site from which rhythmic locomotor-like activity can be induced. Rhythmic locomotor-like activity was recorded from lumbar ventral roots after short trains of stimuli (50 Hz for 0.5-2 seconds) delivered to the VLF. Field potential mapping revealed that single VLF stimuli elicited responses in the ipsilateral ventrolateral medulla. Tract-tracing experiments by using biocytin, pressure-injected into the VLF, showed that only a small number of brainstem neurons were labeled and these were scattered bilaterally in the ventrolateral and lateral medulla. Dense concentrations of nerve terminals were found in the lateral reticular nucleus ipsilateral to the stimulation site. Labeled spinal cord neurons included a primary population of large cells distributed bilaterally in lamina VII from T13 to L4, with peak numbers in L2 ipsilaterally and in L3 contralaterally. Intracellular recordings revealed that some L2 and L3 neurons with rhythmic responses to VLF stimulation could be activated antidromically from the VLF, with latencies of less than 1.0 msec. These observations led us to speculate that the superficial VLF carries a locomotor-related tract originating bilaterally in lumbar lamina VII and terminating in the ipsilateral medulla, including the lateral reticular nucleus. This pathway may be part of the spinoreticular or spinoreticulotectal pathway that has been described in many species, the function of which has only loosely been ascribed.  相似文献   
110.
Epidural infiltration by leukemic cells in Acute Non Lymphoblastic Leukemia (ANLL), and extradural granulocytic sarcomas as a cause of spinal cord compression are extremely rare phenomena. Very few cases have been recorded in the literature. In this brief case report we describe a young patient with acute myeloblastic leukemia (M4, FAB) who presented with sudden spinal cord compression during relapse after bone marrow transplantation. The literature on this subject is also reviewed.  相似文献   
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