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101.
某些中枢神经元通过分叉轴突向两个以上核团投射。轴突分叉点的位置通常由计算轴突主干传导时间予以估测。但是,本工作用该法的4个公式计算细胞内或细胞外记录到的数据未能得到一致和可信的数值。结果提示,计算法的原理是不合理的,并至少对在细胞内或细胞外记录条件下估测轴突分叉点是不适用的。 相似文献
102.
Autonomic dysfunction is frequent in patients with multiple sclerosis (MS). The sympathetic skin response (SSR) and the R-R interval variation (RRIV) are simple electrophysiologic tests for the assessment of central and peripheral autonomic disturbances. Both tests were performed in 60 patients with clinically definite MS and 30 controls. The SSR was recorded simultaneously from both upper and both lower limbs. In all volunteers normal responses were recorded from the four limbs, but 39 patients (65%) showed abnormal responses in at least one limb. The reduction in amplitude of the response was correlated with patients' EDSS. In individual limbs, the SSR amplitude correlated with weakness, spasticity and cerebellar dysfunction, but was not sufficiently related to the deep sensory loss. The RRIV was abnormal in 48 MS patients (80%), as compared to the controls, but showed no significant relationship either to the EDSS or to the SSR. The sensitivity of SSR and RRIV is high and comparable with that of visual and somatosensory evoked potentials. 相似文献
103.
T. Nishikawa H. Kuwahara A. Tsuda M. Tanaka I. Koga Y. Uchida 《Human psychopharmacology》1990,5(4):363-368
Ceruletide, a potent analogue of cholecystokinin, was administered by injection to eight schizophrenics treated with neuroleptics. We examined the dose–response effect on microvibration (MV) recorded from the chin of these patients. After 15 min of bed rest, MV was recorded for 5 min as a control recording. Subsequently, saline or ceruletide, at a dose of either 0.4 m?g/kg or at 0.8 m?g/kg, was injected according to a Latin square design with an interval of 4 weeks for washing out the drug effect and MV was recorded for 30 min. MV data obtained were subjected to the fast Fourier transform and an average power spectrum was computed. A three-way analysis of variance for these data was performed upon dose-effect, time-effect after treatment, and band-effect of the average power spectrum. The present results were similar to previous findings which had revealed effects of ceruletide on tardive dyskinesia symptoms, namely, the effects of ceruletide on MV were different according to the subjects (three cases: facilitation followed by inhibition, three cases: inhibition, two cases: no effects). The dose-response curve of ceruletide appears to be linear in some cases and an inverted U-shape in other cases. Present findings showed small doses of systemically administered ceruletide would modify muscle tonus of schizophrenics under chronic treatment of neuroleptics, and provided further reason for the therapeutic drug of tardive dyskinesia. 相似文献
104.
热休克反应对大鼠感染性脑水肿脑组织诱生型一氧化氮合酶mRNA表达的影响 总被引:1,自引:0,他引:1
:探讨热休克反应 (HSR)对百日咳杆菌所致的大鼠感染性脑水肿诱生型一氧化氮合酶 (iNOS)mRNA表达的影响。方法 :从大鼠左侧颈内动脉注入百日咳菌液制备感染性脑水肿 (感脑 )模型 ,采用组织细胞原位杂交技术检测脑组织iNOSmRNA的表达。结果 :生理盐水组、4h感脑组及 4h热休克处理组均未见iNOSmRNA表达 ,8h ,2 4h时感染性脑水肿组均有明显的杂交信号 ,以 2 4h更为明显 ;而 8h ,2 4h热休克处理组仅有少数细胞有阳性信号。结论 :热休克反应对感染性脑水肿的保护作用可能与抑制iNOSmRNA的表达有关 相似文献
105.
Michael Bach Graham E. Holder 《Documenta ophthalmologica. Advances in ophthalmology》1996,92(3):193-202
The pattern electroretinogram was recorded to checkerboard stimuli with a wide range of check sizes and two stimulus field
sizes. Check sizes ranged from 0.25° to 7° (field size, 16°×14°) and 0.25° to 15° (field size, 32°×27°) in 14 and seven subjects,
respectively. Reversal rate was 4.5/s. For minimal intrusion of blink artifacts the interrupted stimulation technique was
employed. The P50 and N95 components of the pattern electroretinogram were evaluated separately. With both stimulus field
sizes amplitude of P50 and N95 was maximal between 0.75° and 1°. With smaller check sizes the amplitude dropped monotonically.
With larger check sizes field size played a role: with the 16°×14° field, P50 gradually dropped to 89% from 1° to 7°, which
was paralleled by N95 only up to 7°, where N95 dropped to 81% (p<0.05). With the 32°×27° field, there was no significant difference in size dependency between P50 and N95 for large checks,
both components staying constant from 1° to 15° We conclude that there is only minor large-check attenuation of the pattern
electroretinogram, especially with a large field. The apparent field-size dependency may explain previous discrepancies in
the literature. 相似文献
106.
Jill Taylor Randall Weinberg Bernard Languet Philippe Desmettre Enzo Paoletti 《Vaccine》1988,6(6):497-503
The natural host of fowlpox virus is limited to avian species. When inoculated into non-avian tissue culture cells, however, fowlpox virus can initiate an abortive infection. A fowlpox virus was engineered to express rabies virus glycoprotein. On inoculation of the recombinant virus into either avian (permissive) or non-avian (non-permissive) cells, the rabies glycoprotein was expressed as a membrane-associated antigen. Inoculation of the fowlpox virus recombinant into six different species of mammal resulted in specific immune responses to both fowlpox antigens and to rabies glycoprotein. In mice, cats and dogs the immune response was sufficient to protect against a live rabies virus challenge. The results demonstrate the utility of a fowlpox virus vector in immunizing non-avian species against rabies in the absence of productive viral replication of the fowlpox vector. 相似文献
107.
Masaru Kato Rie Kobayashi Ikuo Watanabe 《Documenta ophthalmologica. Advances in ophthalmology》1993,84(1):71-81
An unusual form of scotopic electroretinogram with a bright white stimulus, which consisted of a rectangular a-wave of normal amplitude and a b-wave of supernormal amplitude, was recorded in three patients with cone dysfunction. In addition to poor visual acuity, abnormal color vision and reduced amplitude of the photopic electroretinogram, these patients showed a 2-log unit elevation of the dark-adaptation threshold. Funduscopic examination and fluorescein angiography revealed fine granular pigment disturbances at the mascula. The relationship between the response of the dark-adapted electroretinogram versus stimulus intensity was unique to these patients. The b-wave thresholds were elevated by 1 log unit. The b-waves were reduced in amplitude and markedly delayed in implicit time to dim stimuli, but supernormal in amplitude and normal in implicit time to bright stimuli.Abbreviations GMP
guanosine monophosphate 相似文献
108.
MASAAKI KATO MD NAOFUMI KAJIMURA MD MASANORI SEKIMOTO MD TSUYOSHI WATANABE MD KIYOHISA TAKAHASHI MD 《Psychiatry and clinical neurosciences》1998,52(2):262-263
Abstract We tried melatonin treatment in two patients with non-24 h sleep-wake syndrome, who did not respond to treatments by vitamin B12 , bright light therapy, or hypnotics. In one patient, melatonin 5–10 mg improved difficulty in falling asleep and in waking, although it failed to improve the sleep-wake rhythm. In another patient, melatonin 3 mg successfully changed the sleep-wake rhythm from free-running pattern to delayed sleep phase pattern. However, melatonin re-administration after a 4-month drug-free interval failed to improve his free-running sleep-wake rhythm. These results suggest that melatonin acted as a sleep inducer in one patient and as a phase setter in the other, although the effect on the latter patient was transient. 相似文献
109.
Bernhard R. Slaap Irene M. van Vliet Herman G. M. Westenberg Johan A. Den Boer 《Psychopharmacology》1996,127(1-2):353-358
Little is known about biological predictors of treatment response in panic disorder (PD). In the present study heart rate,
blood pressure, plasma cortisol and plasma MHPG were investigated at baseline in a sample of 44 PD patients as possible predictors
for nonresponse to treatment. We used a strict definition of nonresponse to find patients who did not respond at all after
12 weeks of treatment with brofaromine or fluvoxamine. Patients were considered nonresponders when they fulfilled two criteria:
they did not show a 50% reduction of agoraphobic avoidance and they still experienced panic attacks at endpoint. The variables
that differed significantly between the groups were used to predict nonresponse to drug therapy. Using this strict definition
of nonresponse, 15 patients (32.6%) were considered nonresponders. These patients were characterised by a higher plasma MHPG
concentration and a higher heart rate at baseline. These variables were subsequently used to predict nonresponse. 相似文献
110.
100例2型糖尿病患者交感神经皮肤反应研究 总被引:1,自引:0,他引:1
目的探讨交感神经皮肤反应(SSR)检测在评价2型糖尿病(T2DM)自主神经损害中的价值.方法对100例T2DM患者进行SSR检测,30例健康志愿者作为对照.结果2组SSR的起始潜伏期、N波潜伏期、波幅、面积比较差异有显著性意义(P<0.05),P波潜伏期差异无显著性意义(P>0.05).T2DM组72例(72%)患者至少有一肢SSR异常.血糖控制满意组和血糖控制不良组比较,起始和N波潜伏期差异有统计学意义(P<0.05),波幅和面积无显著性意义(P>0.05).T2DM组病程<5年与病程≥5年比较,潜伏期、波幅、面积差异均无统计学意义(P>0.05).结论SSR可作为评价T2DM自主神经损害的客观电生理指标;T2DM患者SSR与血糖控制水平相关,与病程无关. 相似文献