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991.
S. R. Bareggi M. Porta M. Collice G. Calderini M. Ferrara P. L. Morselli 《Acta neurochirurgica》1976,35(1-3):161-170
Summary Homovanillic acid (HVA) and 5-hydroxyindolacetic acid (5-HIAA) in ventricular CSF were determined in 19 patients (12 female 7 male) with brain tumours. No relationship was found between ventricular fluid pressure (VFP) and levels of HVA and 5-HIAA. A relationship was observed between ventricular CSF, HVA concentrations and tumour induced alterations in CSF dynamics. HVA concentrations were very high in patients whose tumours involved the third ventricle, the aqueduct, or the fourth ventricle, producing marked alterations in CSF flow. HVA concentrations significantly lower than in controls were observed in cases where tumours involved the lateral ventricles. Concentrations of acid metabolites in patients with little or no alteration in CSF dynamics corresponded with those in patients with other neurosurgical disorders. 相似文献
992.
G. Schreinicke K. Scheuch 《International archives of occupational and environmental health》1976,36(3):183-195
Zusammenfassung Mit 40 Versuchspersonen wurde Kompensationstracking durchgeführt. Anhand des Leistungsparameters Regelfehler wurden 2 Gruppen gebildet, bei denen untersucht wurde, ob sie sich im Aktivierungsverhalten unterscheiden. Es wurde gefunden, daß die Herzfrequenz- und Atemfrequenzsteigerungen in allen Versuchsabschnitten bei der Gruppe mit guter Trackingleistung signifikant höher waren. Die Streuung der Herzfrequenz war bei der schlechten Gruppe geringer.Die Aktivierungsvariablen Herz- und Atemfrequenz unterscheiden sich am deutlichsten in der jeweils ersten Belastungsminute der Versuchsabschnitte, dabei spiegelt die Herzfrequenz die Aufgabenschwierigkeit besser wider als die Atemfrequenz.Die Untersuchung der Korrelation zwischen dem Leistungsparameter Regelfehler und Herzfrequenzanstieg ergibt bei der Gruppe mit schlechterer Trackingleistung immer negative Werte für r, die in 3 Belastungsabschnitten signifikant sind. Bei der Gruppe mit guter Trackingleistung besteht eine positive Korrelation zwischen Herzfrequenzanstieg und Regelfehler bei geringerer statistischer Sicherheit.Die Ergebnisse werden diskutiert und Schlußfolgerungen für die psychophysiologische Eignungsbeurteilung werden abgeleitet. 相似文献
993.
Lehmann O Jeltsch H Lehnardt O Pain L Lazarus C Cassel JC 《The European journal of neuroscience》2000,12(1):67-79
This study assessed behavioural and neurochemical effects of i.c.v. injections of both the cholinergic toxin 192 IgG-saporin (2 microgram) and the serotonergic toxin 5,7-dihydroxytryptamine (5,7-DHT; 150 microgram) in Long-Evans female rats. Dependent behavioural variables were locomotor activity, forced T-maze alternation, beam walking, Morris water-maze (working and reference memory) and radial-maze performances. After killing by microwave irradiation, the concentrations of acetylcholine, monoamines and 5-hydroxyindoleacetic acid (5-HIAA) were measured in the hippocampus, frontoparietal cortex and striatum. 192 IgG-saporin reduced the concentration of acetylcholine by approximately 40% in the frontoparietal cortex and hippocampus, but had no effect in the striatum. 5,7-DHT lesions reduced the concentration of serotonin by 60% in the frontoparietal cortex and 80% in the hippocampus and striatum. Noradrenaline was unchanged in all structures except the ventral hippocampus where it was slightly increased in rats given 192 IgG-saporin. Cholinergic lesions induced severe motor deficits but had no other effect. Serotonergic lesions produced diurnal and nocturnal hyperactivity but had no other effect. Rats with combined lesions were more active than those with only serotonergic lesions, showed motor dysfunctions similar to those found in rats with cholinergic lesions alone, and exhibited impaired performances in the T-maze alternation test, the water-maze working memory test and the radial-maze. Taken together and although cholinergic lesions were not maximal, these data show that 192 IgG-saporin and 5,7-DHT lesions can be combined to selectively damage cholinergic and serotonergic neurons, and confirm that cholinergic-serotonergic interactions play an important role in some aspects of memory, particularly in spatial working memory. 相似文献
994.
Cadiou H Sienaert I Vanlingen S Parys JB Molle G Duclohier H 《The European journal of neuroscience》2000,12(8):2805-2811
In addition to the activation of cAMP-dependent pathways, odorant binding to its receptor can lead to inositol 1,4,5-trisphosphate (InsP3) production that may induce the opening of plasma membrane channels. We therefore investigated the presence and nature of such channels in carp olfactory cilia. Functional analysis was performed by reconstitution of the olfactory cilia in planar lipid bilayers (tip-dip method). In the presence of InsP3 (10 microM) and Ca2+ (100 nM), a current of 1.6 +/- 0.1 pA (mean +/- SEM, n = 4) was measured, using Ba2+ as charge carrier. The I/V curve displayed a slope conductance of 45 +/- 5 pS and a reversal potential of -29 mV indicating a higher selectivity for divalent cations. This current was characterized by two mean open times (3.0 +/- 0.4 ms and 42.0 +/- 2.6 ms, n = 4) and was strongly inhibited by ruthenium red (30 microM) or heparin (10 microg/mL). Importantly, the channel activity was closely dependent on the Ca2+ concentration, with the highest open probability (Po) at 100 nM Ca2+ (Po = 0.50 +/- 0.02, n = 4). Po is lower at both higher and lower Ca2+ concentrations. A structural identification of the channel was attempted by using a large panel of antibodies, raised against several InsP3 receptor (InsP3R)/Ca2+ release channel isoforms. The type 1 InsP3R was detected in carp cerebellum and whole brain, while a lower molecular mass InsP3R, which may correspond to type 2 or 3, was detected in heart, whole brain and the soma of the olfactory neurons. None of the antibodies, however, cross-reacted with olfactory cilia. Taken together, these results indicate that in carp olfactory cilia an InsP3-dependent channel is present, distinct from the classical InsP3Rs localized on intracellular membranes. 相似文献
995.
Serotonin in mania and in the mechanism of action of mood stabilizers: a review of clinical studies 总被引:2,自引:0,他引:2
Objectives: Serotonin (5-hydroxytryptamine, 5-HT) was implicated in the pathophysiology of manic-depressive illness as early as 1958. Although extensive evidence has accumulated since then to support 5-HT's role in depression, relatively fewer studies examined its role in mania. The purpose of this paper was to review and summarize the current state of knowledge on the role of 5-HT in mania and its treatment.
Methods: We systemically reviewed clinical studies of 1) 5-HT function in mania and 2) 5-HT in the mechanism of action of mood stabilizers, including lithium and anticonvulsants.
Results: Review showed that cerebrospinal fluid, postmortem, platelet, neuroendocrine challenge, and tryptophan depletion studies provided some evidence to support the hypothesis that a 5-HT deficit is involved in mania and that enhancement of 5-HT neurotransmission exerts a mood-stabilizing effect.
Conclusions: There is some evidence from clinical studies for the contribution of 5-HT in mania and in the mechanism of action of mood stabilizers. However, it is very likely that other neurotransmitters also play important roles. Future directions for research include 1) in vivo study of 5-HT receptor subtypes using positron emission tomography, 2) investigation of the interaction between 5-HT and other neurotransmitter systems, and 3) determination of the relationships between diagnostic subtypes of mania and 5-HT function and other neurotransmitter systems. 相似文献
Methods: We systemically reviewed clinical studies of 1) 5-HT function in mania and 2) 5-HT in the mechanism of action of mood stabilizers, including lithium and anticonvulsants.
Results: Review showed that cerebrospinal fluid, postmortem, platelet, neuroendocrine challenge, and tryptophan depletion studies provided some evidence to support the hypothesis that a 5-HT deficit is involved in mania and that enhancement of 5-HT neurotransmission exerts a mood-stabilizing effect.
Conclusions: There is some evidence from clinical studies for the contribution of 5-HT in mania and in the mechanism of action of mood stabilizers. However, it is very likely that other neurotransmitters also play important roles. Future directions for research include 1) in vivo study of 5-HT receptor subtypes using positron emission tomography, 2) investigation of the interaction between 5-HT and other neurotransmitter systems, and 3) determination of the relationships between diagnostic subtypes of mania and 5-HT function and other neurotransmitter systems. 相似文献
996.
川芎嗪及其衍生物对羟自由基的清除作用 总被引:29,自引:0,他引:29
目的:探讨川芎嗪及其衍生物对羟自由基的清除作用。方法:应用Fenton反应检测并计算50%羟自由基被清除时的药物浓度(EC_(50))。结果:结果显示对羟自由基均有明显清除作用,且呈剂量依赖关系。川芎嗪及其衍生物与苯甲酸和甘露醇的清除作用差异有极显著性(P<0.01),而相互间作用无明显差异(P>0.05)。结论:川芎嗪及其衍生物对羟自由基有明显的清除作用。 相似文献
997.
998.
目的探讨非甾体类5α-还原酶抑制剂DQI对大运动量游泳训练大鼠血清雄激素水平、EPO水平及肾脏组织EPO合成能力的影响。方法以渐增游泳训练为大鼠运动应激模型,运用酶免和放免分析法观察了血睾、血清EPO及血清5α-双氢睾酮的含量,以及运用RT PCR法观察了肾脏组织EPOmRNA的表达水平。结果本运动模型可提高靶组织睾酮向5α-双氢睾酮的转化,而DQI可以显著抑制这一过程,并可以提高肾脏组织EPO的合成能力及血清EPO含量。结论非甾体类5α-还原酶抑制剂DQI对维持及恢复运动能力有一定作用。其机制与整合内源性睾酮及增加内源性EPO有关。 相似文献
999.
含丹参的葡萄糖注射液中5-羟甲基糠醛的检查方法研究 总被引:2,自引:0,他引:2
目的 :研究含丹参和葡萄糖的注射液中 5 羟甲基糠醛的检查方法。方法 :采用高效液相色谱法。结果 :选用色谱柱 :HypersilODS(4.6mm(i.d)× 2 50mm ,5 Micro) ;流动相 :甲醇 0 .5 %冰乙酸 (1 5∶85) ;检测波长 :2 84nm ;柱温 :30 °C ;可分离 5 羟甲基糠醛峰与丹参素峰 ,分离度为 :1 .8。结论 :本法简便、灵敏、准确 ,排除了丹参成分的干扰 ,可用于含丹参的葡萄糖注射液中 5 羟甲基糠醛的检查和质量控制 相似文献
1000.
目的 探讨老年急性心肌梗塞后抑郁与血浆5羟色胺(5-HT)浓度的关系。方法 利用HAMD对抑郁进行评定,同时使用HPLC-EC法检测30例心梗后伴有明显抑郁症状患者的血浆5羟色胺浓度,并与30例不伴明显抑郁症状的患者以及30例健康人进行对照。结果 血浆5-HT含量抑郁组为46.37±24.47(ng/ml),非抑郁组为44.08±13.03(ng/ml),健康对照组为37.01±5.92(ng/ml)。结论 老年急性心肌梗塞患者HAMD与血浆5-HT浓度无相关。 相似文献