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171.
D. M. Jackson C. E. Wallsten E. Jerning P.-S. Hu A. M. Deveney 《Psychopharmacology》1998,139(4):300-310
The aim was to study firstly, the motor effects of a new 5-HT1A antagonist, NDL-249 [(R)-3-(N-cyclopentyl-N-propylamino)-8-fluoro-3,4-dihydro-2H-1-benzopyran-5-carboxamide hydrochloride] and of the reference 5-HT1A antagonist WAY-100 635 [N-(2-(1-(4-(2-methoxyphenyl)piperazinyl))ethyl)-N-(2-pyridinyl) cyclohexanecarboxamide trihydrochloride], in comparison to the 5-HT1A agonist (±)-8-OH-DPAT [(8-hydroxy-2-(di-N-propylamino) tetralin, hereafter 8-OH-DPAT], in rats acclimatised to the automated activity cages; secondly, to study whether
the behavioural effects of NDL-249 and 8-OH-DPAT are sensitive to the 5-HT depleting effects of p-chlorophenylalanine (PCPA); thirdly, to characterise the nature of the antagonist-induced activation seen in the automatic
activity cages with the aid of a behavioural observation analysis; fourthly, to examine the interaction between the 5-HT1Areceptors mediating the behavioural effects and dopamine (DA) receptors. NDL-249 was found to bind in vitro to rat hippocampal
5-HT1A receptors with high affinity and selectivity. In second messenger studies, it was devoid of agonist-like effects. In the
locomotor activity studies, each antagonist significantly increased the incidence of horizontal activity, peripheral activity
and rearing. 8-OH-DPAT, while significantly increasing peripheral and horizontal activities, decreased the incidence of rearing.
PCPA blocked the motor effects of NDL-249 but did not affect those of 8-OH-DPAT. Observational analyses indicated that NDL-249
induced significant increases at one or more doses in sniffing, rearing and locomotion together with a significant reduction
in stillness. WAY-100 635 significantly increased the incidence of rearing, intense grooming and vacuous chewing. The significant
increases in sniffing, grooming and intense grooming and the significant decrease in stillness induced by the DA D1 agonist, SK&F 38393 [(±)-1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol hydrochloride], were not altered by concomitant
pre-treatment with NDL-249. Pre-treatment of rats with either the DA D1 antagonist SCH-23390 (2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol) or the DA D2 antagonist, raclopride, blocked the reduced stillness and increased sniffing and rearing induced by NDL-249. In conclusion,
5-HT1A antagonists including the new selective antagonist, NDL-249, induce mild behavioural activation in rats, which is mediated
probably indirectly via DA systems.
Received: 3 April 1997/Final version: 23 February 1998 相似文献
172.
下体负压作用下心率变异性的线性和非线性动力学分析 总被引:1,自引:1,他引:0
胡志红 《航天医学与医学工程》1998,11(4):235-239
为了评估下体负压作用下心率变异性的变化,本文应用了时域,频域分析和复杂度分析了HRV。受试者为15名健康男性。下体负压作用的强度和时间分别为-2.7kPa,2min;-4.0kPa,3min;-5.3kPa,5min;-6.7kPa,10min。 相似文献
173.
从2105例胃癌癌旁组织中找出微小腺癌31例(〈0.1cm),观察其组织发生的特征,发现胃腺癌的发生有8种形式:①腺颈部干细胞癌变;②表面上皮癌变;③腺上皮癌变;④肠化生上皮癌变;⑤微腺囊癌变;⑥溃疡边缘上皮癌变;⑦扁平腺瘤癌变;⑧贲门交界处柱状上皮癌变。 相似文献
174.
江苏省肾综合征出血热单价灭活疫苗中期免疫效果观察 总被引:5,自引:2,他引:3
观察HFRS单价灭活疫苗中期免疫效果。方法:采用IFAT法及MCPENT法检测荧光抗体及中和抗体。结果:3个试区加强接种人数分别为4052、4407和6354人。加强后,Ⅰ型苗荧光抗体阳性率为72.73%,GMT为14.14;中和抗体阳性率为54.55%,GMT为6.67。D型苗荧光抗体阳性率为75.00%,GMT为11.85;中和抗体阳性率为60%,GMT为9.44。加强后1年,Ⅰ型苗年均保护率为65.52%,Ⅱ型苗则为94.24%。同期,Ⅰ型苗荧光抗体阳性率维持在40%,中和抗体维持在35.00%;Ⅱ型苗荧光抗体阳性率降至10.34%,中和抗体维持在53.85%。结论:两型疫苗均有较好的中期防病效果。 相似文献
175.
“C”型曲线的中耳声学特性改变与鼓室积液的关系 总被引:10,自引:2,他引:8
对40耳声导抗检查为“C”型曲线患耳进行中耳系统共振频率点测试并进行鼓室穿刺抽液,结果表明:共振频率点低于600Hz,患耳鼓室积液阳性率为82.1%,高于600Hz患者鼓室和液阳性率16.7%,提示依据鼓室导抗图和共振频率点测定可初步判断“C”型曲线患耳鼓室积液的可能. 相似文献
176.
本文调查了一个铀水冶厂放射性废物坑的污染情况,发现该坑周围农田及坑附近淠史杭大灌渠水、泥等均受到不同程度污染。这表明,即使处理小型铀水冶厂的放射性废物,在选址、掩埋等各个环节也都应严格做到科学、合理,并且还要做好掩埋后的管理工作。 相似文献
177.
G. Bruce Pike Gary H. Glover Bob S. Hu Dieter R. Enzmann 《Journal of magnetic resonance imaging : JMRI》1993,3(3):531-539
Cross relaxation between macromolecular protons and water protons is known to be important in biologic tissue. In magnetic resonance (MR) imaging sequences, selective saturation of the characteristically short T2 macromolecular proton pool can produce contrast called magnetization transfer contrast, based on the cross-relaxation process. Selective saturation can be achieved with continuous wave irradiation several kilohertz off resonance or short, intense 0° pulses on resonance. The authors analyze 0° binomial pulses for T2 selective saturation, present design guidelines, and demonstrate the use of these pulses in spin-echo imaging sequences in healthy volunteers and patients. Using the phenomenologic Bloch equations modified for two-site exchange, the authors derive the analytic expressions for water proton relaxation under periodic pulsed saturation of the macromolecular protons. This relaxation is shown to be monoexpo-nential, with a rate constant dependent on the saturation pulse repetition rate and the individual and cross-relaxation rates. 相似文献
178.
头孢托仑酯随机双盲对照治疗细菌性感染临床评价 总被引:3,自引:0,他引:3
为评价头孢托仑酯(ME1207)治疗细菌性感染的有效性和安全性,采用随机双盲对照试验和开放试验方法共治疗80例患者,其中ME1207(A药)与头孢克肟(B药)随机双盲各治疗20例(呼吸系统和泌尿系统各10对),ME1207开放试验治疗40例(呼吸系统20例、泌尿系统10例、皮肤软组织感染10例)。每日400mg,疗程7~14d。ME1207痊愈率和有效率在对照试验中为80%和95%,在开放试验中为75%和92.5%,总痊愈率为76.7%,总有效率为93.3%,细菌培养阳性率为100%,细菌清除率在对照试验和开放试验中分别为95%和92.5%。纸片法药敏试验中ME1207敏感株百分率为100%,与头孢哌酮相同,而优于头孢克肟和头孢克洛,明显优于阿莫西林(48.8%)。ME120760例中6例出现不良反应,表现为消化道反应3例,转氨酶升高2例,凝血酶原时间延长1例。与对照药头孢克肟相比在痊愈率、有效率、细菌清除率及不良反应发生方面均无显著性差异(P>0.05)。ME1207在每日400mg剂量下治疗轻、中度细菌感染安全、有效。 相似文献
179.
From the leaves of MELODINUS ACUTIFLORUS a new alkaloid, rhazicine N-oxide ( 2), and two known compounds, deacetylakuammiline ( 3) and 16- EPI-rhazinaline ( 4) were isolated. The structure of 2 was determined by spectral analysis and chemical correlation with rhazicine ( 1). 相似文献
180.
Dose-response curves for the elevation of homovanillic acid (HVA) levels, determined by high performance liquid chromatography using electrochemical detection, in the pre-frontal cortex and caudate of rats after acute treatment with 12 antipsychotic drugs are presented. The order of potency in both brain regions was: haloperidol fluphenazine > loxapine > trifluoperazine > thiothixene > molindone > clopenthixol > chlorpromazine > metoclopramide > thioridazine > clozapine > sulpiride. This ranking is roughly correlated with that based on clinical potencies. The relative elevation of the content of HVA was weaker in the pre-frontal cortex than in the caudate for all drugs tested, except clozapine at a high dose. 相似文献