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941.
Blockade of presynaptic α-receptors and of amine uptake in the rat brain by the antidepressant mianserine 总被引:12,自引:0,他引:12
Summary Mianserine (Org GB 94, Tolvon®) is 1, 2, 3, 4, 10, 14b-hexahydro-2-methyl-dibenzo [c, f] pyrazino [1, 3-a] azepine hydrochloride, a new antidepressant drug. Its effect on noradrenaline release and its capacity to inhibit amine uptake were investigated. Mianserine increased the release of 3H-noradrenaline from field-stimulated cortical slices previously labelled with the tritiated transmitter. The assumption that this effect is due primarily to the blockade of the presynaptic noradrenergic -receptors is supported by the fact that mianserine failed to augment 3H-noradrenaline release further after blockade of the presynaptic -receptors by phentolamine. In the reciprocal experiment, phentolamine failed to augment 3H-noradrenaline release after exposure of the slices to mianserine. The hypothesis is further reinforced by the fact that mianserine antagonized the reduction of 3H-noradrenaline release by clonidine in the same manner as the -blocking drugs phentolamine and phenoxybenzamine. Mianserine inhibited noradrenaline uptake in vitro and in vivo (in the rat heart and midbrain-diencephalon synaptosomes from pretreated rats.) Only a marginal inhibition of serotonin uptake was observed.It therefore appears that mianserine increases the concentration of noradrenaline in the synaptic cleft by blocking the presynaptic -receptors and inhibiting uptake. Whether or not this increase has functional consequences at postsynaptic noradrenergic receptor sites is unknown. It is possible, however, that postsynaptic receptor blockade counteracts the increase in available noradrenaline.A part of these results was presented at the 16th Spring Meeting of the German Pharmacological Society, Mainz, March 4–7, 1975 相似文献
942.
Lamotrigine is a broad-spectrum antiepileptic drug which is thought to act in part via a use-dependent blockade of voltage-sensitive sodium channels to stabilise the neuronal membrane. This results in the inhibition of the excessive release of excitatory amino acids, such as glutamate, during epileptic activity. An open, multicentre, prospective trial of lamotrigine was carried out in adult patients with drug-resistant epilepsy on monotherapy with carbamazepine or valproate. The primary aim of the study was to assess add-on lamotrigine withdrawing to monotherapy. 28-week clinical trial was divided into 4 phases: (1) Dose escalation period (4 weeks), (2) Add-on period (8 weeks), (3) Standard AED withdrawal period (8 weeks), (4) Lamotrigine monotherapy (8 weeks). Thirty-three patients were previously treated with valproate, 44 with carbamazepine. Of 77 patients recruited into the study, 64 patients (83%) completed add-on therapy, 49 patients (64%) completed lamotrigine monotherapy. 44% of all patients during the add-on phase and 48% during lamotrigine monotherapy had a reduction in seizure frequency of at least 50% compared with pre-study period. 13% of all patients achieved seizure freedom during add-on therapy and 18% during monotherapy. Improvement of Visual Analogue Scale (VAS) scores was observed in 65% and 57% patients respectively. A significant proportion of patients could be successfully converted to lamotrigine monotherapy. Lamotrigine was also generally well tolerated. 23 patients (30%) had at least one adverse event (AE), but only 1/4 of all AEs might be reasonably regarded as an effect of the medication. 7 patients (9%) discontinued prematurely from the study due to adverse event. More AEs were observed in add-on therapy than in lamotrigine monotherapy. The safety profile was consistent with that seen during other clinical trials with lamotrigine. CONCLUSIONS: 1. Lamotrigine is effective AED in add-on and monotherapy (responders rate--44% and 48% respectively). 2. In most cases conversion from add-on therapy to monotherapy can be done successfully. 3. Lamotrigine is a safe and well-tolerated drug. 相似文献
943.
Researchers from Japan, China and Singapore have initiated a collaborative project, with the aim of comparing adolescent quality of life (QOL) internationally. This study presents the primary results of the investigation conducted in Beijing, China, and Kobe, Japan. The 70-item Quality of Life Questionnaire for Adolescents (QOLQA) was developed and evaluated in Japan and China. In total, 1114 Japanese and 613 Chinese junior high school students, aged 12-15 years, completed the questionnaire. Chinese students scored significantly higher than the Japanese students in overall QOL scores and in most domains. For both groups, subjects had highest score in the independence domain and lowest in psychological domain. In terms of overall QOL score, Chinese male students ranked first, followed by Chinese girls, Japanese boys, and Japanese girls. In the Japanese group, a continuing decrease of QOL scores with age was observed without exception, but no such tendency was present in their Chinese counterparts. No parallel relationship was observed between the higher level of economic development and better quality of life. The results also suggest that mental health promotion should be a priority in improving overall quality of life of adolescents both in Japan and China. 相似文献
944.
头孢克洛咀嚼片的人体相对生物利用度 总被引:1,自引:0,他引:1
目的 :研究 2 0名男性健康受试者单剂量口服 75 0mg头孢克洛咀嚼片和胶囊后 ,头孢克洛咀嚼片相对生物利用度。方法 :采用RP HPLC测定人血浆中头孢克洛浓度 ,并用 3P97程序拟合。结果 :单剂量口服 75 0mg头孢克洛咀嚼片和胶囊后的AUC0→ 3 5h分别为 (2 1 90± 3 3 5 ) ,(2 2 4 8± 3 66) μg·h·mL-1;cmax分别是 (18 10± 3 77) ,(18 3 6± 4 0 3 ) μg·mL-1;tmax分别是 (0 70± 0 2 0 ) ,(0 80± 0 2 0 )h ;T1/ 2 分别为 (0 4 9± 0 0 6) ,(0 5 6± 0 17)h ,头孢克洛咀嚼片和胶囊的所有药动学参数经统计学处理均无显著性差异 (P >0 0 5 )。结论 :头孢克洛咀嚼片和胶囊具有生物等效性 相似文献
945.
傍刺天柱穴为主治疗颈性眩晕疗效观察 总被引:16,自引:1,他引:16
目的 :观察多针刺法与单刺法的效应差异。方法 :将 62例确诊为颈性眩晕的病人随机分为2组 :治疗组以傍刺天柱穴为主 ;对照组取穴与治疗组同 ,均按常规单刺 ,对治疗后 2组病人的主要症状进行评估 ,同时分别经颅脑多普勒检查 ,观察双侧椎动脉、椎 基底动脉的平均血流速。结果 :治疗后 2组均有显著疗效 (P <0 0 5) ;治疗后 2组椎动脉、椎 基底动脉平均血流速有明显改善 (P <0 0 1 ,P <0 0 5) ,2组间比较显示总有效率及颅脑多普勒指标差异均有显著性意义 (P <0 0 5)。结论 :傍针刺较单刺法在治疗颈性眩晕时更有效 相似文献
946.
目的:评价环抱式接骨板与骨卡环治疗四肢长骨干粉碎性骨折的临床疗效。方法:采用西脉环抱式接骨板与骨卡环治疗四肢长骨干粉碎性骨折50例。结果:50例上下肢骨干粉碎性骨折经1~2年随访,均在术后4个月内愈合,功能恢复良好,无接骨板与骨卡环断裂及再骨折。结论:西脉环抱式接骨板与骨卡环具有形状记忆功能及持续的自动加压功能,固定可靠,骨卡环有良好的辅助固定作用,持续的抱合力使骨折愈合周期缩短。不钻孔.不用螺钉,人为损伤小,操作简便,缩短了手术时间,可用于一些特殊类型的骨折。但该固定器不适用于扁平骨及干骺段等不规则部位骨折。 相似文献
947.
948.
为了研制一种材料、形态、弹性、刚性均符合肱骨髁上骨折外固定需要的改良夹板。从 1999年 7月~ 2 0 0 2年 8月采用改良肱骨髁上骨折夹板治疗 2~ 12岁小儿肱骨髁上骨折 80例 ,其中伴神经损伤 8例 ,血管挫伤 2例 ,随访 6~ 2 6个月 ,平均 15个月。结果未出现因夹板固定导致Volkmann缺血性肌挛缩和神经损伤 ,固定后肿胀加剧明显减轻 ,神经损伤 3个月内均恢复。骨折治愈 73例 ,好转 4例 ,未愈 3例 ,出现肘内翻 6例 ,携带角减少 2 0°以上者 3例 ,肘外翻 1例 ,肘内翻发生率为 7.5 %。认为该夹板前托不仅与肢体生理弧度、外形相适应 ,使肱动脉不易受压 ,又能与后托合用时控制前臂旋转 ,利于骨折稳定 ,对尺偏型骨折配合下段弯曲成向外 15°的内外侧夹板 ,可减少肘内翻。钢丝内衬的使用 ,使调节夹板角度成为可能 ,扩大了夹板固定的适用范围。说明改良肱骨髁上骨折夹板是治疗肱骨髁上骨折理想的外固定材料。 相似文献
949.
不同类型苷类在大孔吸附树脂上的吸附纯化特性研究 总被引:10,自引:1,他引:10
目的 :研究黄芩苷等 3种具有不同类型母核的苷类中药成分在大孔吸附树脂上的吸附纯化特性。方法 :以黄芩、栀子和白芍为样本考察它们在D101等 6种不同树脂上的吸附纯化特性。结果 :6种非极性树脂对 3种苷类总体静态吸附能力为黄芩苷 >芍药苷 >栀子苷 ,其洗脱溶剂分别为 75% ,25% ,45%的乙醇 ,洗脱率分别为60% ,93% ,93%。结论 :具有相似母核结构的苷类分子在同一树脂上吸附能力不一定相似 ,但吸附力的大小与分子结构有关 ,对苯乙烯型树脂而言 ,被吸附的分子母核双键数目越多 ,分子与树脂吸附作用力越大。 相似文献
950.
目的探讨颅内压与颅内动静脉压的相关性.方法行侧脑室置管接多功能测压表,颅内动静脉置管接有创血压监护仪.再用结扎一侧颈内动脉、人工窒息等方法致实验狗脑水肿高颅压.先后经颅内动脉、外周静脉注射不同剂量的甘露醇,记录不同时段的颅内压、颅内动静脉压.结果脑水肿形成后颅内压、颅内静脉压逐渐上升,使用甘露醇脱水后两者又逐渐下降,二者呈正相关.颅内动脉注射小剂量甘露醇15分钟即可达到明显的降颅压效果,与外周静脉给药相比有显著性差异(P<0.05).结论颅内压与颅内静脉压呈正相关,与颅内动脉压无相关性.颅内动脉注射小剂量甘露醇即可达到良好的脱水效果,起效更快. 相似文献