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71.
Our study aimed to investigate the cardiovascular autonomic regulation related to the wearing-off phenomenon in Parkinson's disease (PD). We measured blood pressure (BP) and heart rate (HR) at rest and during orthostatic test in 16 patients with PD with wearing-off and in 15 patients with PD without wearing-off both before (baseline) and repetitively at 1-h intervals for up to 4 h after the morning PD medication dose.
The patients with wearing-off had fluctuation of BP during the observation period, BP increasing when the motor performance worsened and vice versa. The mean supine BP was at its highest at the baseline measurement (patients with wearing-off, 145 ± 18 mmHg; patients without wearing-off, 138 ± 17 mmHg), fell during the first hour (patients with wearing-off, 119 ± 17 mmHg; patients without wearing-off, 126 ± 18 mmHg), and then rose again toward the end of the observation period (patients with wearing-off, 136 ± 15 mmHg; patients without wearing-off, 138 ± 18 mmHg). This BP change was statistically significant only in PD patients with wearing-off ( P  < 0.001).
In conclusion, BP seems to fluctuate with motor impairment in PD patients with wearing-off. This fluctuation may represent autonomic dysfunction caused by the PD process itself, the effect of PD medication, or both.  相似文献   
72.
Iniencephaly is a rare, lethal, axial dysraphic malformation complex diagnosed on the basis of three cardinal features: deficiency of the occipital bone, cervicothoracic spinal retroflexion, and rachischisis. The majority of the patients also have various associated viscerae malformations. An iniencephalic female fetus delivered at 355/7 weeks of gestation revealed severe anomalies of the central nervous system and the spine: the cerebellar vermis was hypoplastic, the medulla oblongata was flattened and broadened, and the cervical canal was widely patent dorsally. The thoracolumbar spinal cord had a duplicated central canal and lacked a dorsal fissure, representing a minor degree of diastematomyelia. The cervicothoracic spine showed severe bony anomalies including aplasia and fusion of vertebral bodies.  相似文献   
73.
用神经组织学方法观察了兔、猫、狗、猴梭曼中毒急救治疗后CNS的病理变化.结果表明,CNS病变程度随着惊厥持续时间的延长而加重,抗惊剂可以保护CNS免受损伤.不同种动物梭曼引起的CNS病变基本相似,均为神经细胞的缺血性改变.主要病变包括大脑皮质、丘脑、海马、小脑和脊髓的神经细胞尼氏体溶解、核浓缩和细胞表面结痂.由于CNS病变与惊厥有密切关系,因此梭曼中毒后必须应用抗惊剂.  相似文献   
74.
Abstract Enteric reflex pathways were studied in isolated segments of guinea-pig distal colon by recording the electrical responses to distension from the muscularis externa with suction electrodes. The end of the electrode wire were in the circular muscle and thus the recordings discussed below are deduced to be primarily from this layer. Moreover, intracellular microelectrodes in circular muscle cells and suction electrodes recorded similar events. Spontaneous activity consisted of myogenic slow waves at about 25 min -1 and transient biphasic potentials at about 6 min-1 and 3-sec duration which were dependent on a stimulus from the enteric nervous system as they were blocked by tetrodotoxin (0.5 μM), d-tubocurarine (30 μM) and hexa-methonium (100 μM). Atropine (0.8 μM) blocked the depolarizing part of the biphasic potentials and unmasked transient spontaneous inhibitory junction potentials (IJPs) (~2-sec duration) which appeared to be responsible for the hyperpolarizing part of the biphasic potential. Three different responses were observed at sites oral to distension of the colon: a transient depolarizing response that was cholinergic (blocked by atropine (0.8 μM); ascending cholinergic excitation) and, after atropine, a transient IJP (ascending inhibition) which was followed by a transient non-cholinergic depolarizaton (ascending non-cholinergic excitation) that was sometimes followed by several cycles of slow wave activity. The oral responses to anal distension were also blocked by the nicotinic antagonists and were similar to the neurogenic spontaneous events, which also appeared to originate from activity in ascending nervous pathways. Four different responses were observed following distension of the oral end of the segment: an IJP followed by a prolonged phase of hyperpolarization that lasted for the duration of the distension (descending inhibition); a burst of depolarizing potentials (for up to 30 sec) that followed the termination of distensions up to 25 sec and was blocked by atropine (0.8 μM) (delayed cholinergic excitation), and a transient non-cholinergic response that immediately followed the termination of distension (non-cholinergic ‘off’ response). Apamin (0.5 μM) reduced the amplitude of the spontaneous IJPs and evoked IJPs. After apamin, distension evoked a small transient hyperpolarization at oral sites, which was similar to spontaneous events, and the prolonged hyperpolarization at anal sites. A second distension given within 20 sec of the first evoked an IJP of reduced amplitude at oral sites in every preparation. In contrast, the amplitudes of the oral Cholinergic excitation and descending inhibition were relatively unaffected by reducing the interval between distensions. Thus distension stimulates excitatory and inhibitory motor neurons supplying the circular muscle both oral and anal to the stimulus. The polarity of the reflex relies in part on the differences in timing and duration of responses as well as the transmission characteristics of the nervous pathways.  相似文献   
75.
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   
76.
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   
77.
伴交感神经症状颈椎病临床评价初步探讨   总被引:5,自引:1,他引:4  
目的报告伴交感神经症状颈椎病的临床评价方法及其初步结果。方法回顾性分析2002~2007年本治疗组伴交感神经症状的颈椎病患者47例,其中男19例,女28例,男女比例为1∶1.5;年龄为34~72岁,平均50.5岁。入选条件:①明确诊断为脊髓型或神经根型\脊髓神经根混合型颈椎病。②均有交感神经症状。③患者均行颈前路减压植骨融合内固定手术,术中均切除后纵韧带。其中8例术前影像学显示有椎节不稳,其余患者未见明显钩椎关节骨质增生及颈椎不稳。交感神经症状包括:眩晕,头痛,恶心呕吐,耳鸣,视物模糊,心慌,记忆力下降,心动过速或心动过缓或早搏等心电图异常,胃肠道症状,面部潮红,出汗等。交感神经症状评价采用20分评分法及患者主观满意度评定。患者主观满意度分为优、良、可、差4个等级。结果所有患者术后均获10~48个月随访,术前交感症状评分6.0分;术后2.8分;患者主观满意度19例为优,16例为良,8例为可,4例为差,有效率为87.5%。结论切除后纵韧带的颈前路减压植骨内固定术对交感神经症状具有一定治疗作用。  相似文献   
78.
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   
79.
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   
80.
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   
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