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1.
Deficit in active and inhibitory avoidance behaviour has been found in pentylenetetrazole (PTZ)-kindled rats. This supports the view that memory deficit is an integral part of epilepsy. In the present study we examined the effect of the nootropic drugs piracetam and fipexide on memory deficit induced by PTZ-kindling in shuttle-box- and step-down-trained rats. The retention in piracetam- and fipexide-treated animals was significantly improved compared to the kindled controls. The mechanisms of action of the two drugs are considered. The favourable effects of nootropic drugs in cases of amnesia provoked by PTZ-kindling might be of interest in clinical practice.  相似文献   
2.
Postpartum hemorrhage today: ICM/FIGO initiative 2004-2006.   总被引:3,自引:0,他引:3  
Postpartum hemorrhage (PPH) is the main cause of maternal mortality. Yet, even though solutions have been identified, governments and donor countries have been slow to implement programs to contain the problem. While poverty and low educational level remain the underlying cause of PPH, the current literature suggests that active management of the third stage of labor can prevent it. The International Confederation of Midwives (ICM) and the International Federation of Gynecology and Obstetrics (FIGO) are attempting to address the chronic PPH crisis by educating their members on best practices and on troubleshooting where resources are inadequate. Some studies found oxytocin to be preferable to misoprostol in settings where active management is the norm. However, secondary clinical effects may prove more troublesome with oxytocin than with misoprostol, and misoprostol may prove to be more practical and equally effective in low-resource settings. Two new interventions are also proposed, the anti-shock garment and the balloon tamponade.  相似文献   
3.
GraVes眼病炎性活动期与静止期血清sICAM-1水平的研究   总被引:1,自引:1,他引:0  
目的:研究可溶性细胞间粘附因子-1(sICAM-1)在Graves眼病(GO)炎性活动期与静止期的水平差异及其与各项甲状腺功能指标的关系。方法:将GO炎性活动期与静止期患者,Graves病(GD)无眼病患者及正常对照,分为A、B、C、D四组,抽取空腹静脉全血,测血清sICAM-1,各组间进行比较。并分析各组sICAM-1与FT3、FT4、TG、TM的相关关系。结果:①A、B、C组患者血清sICAM-1均明显高于正常对照组(P<0.05)。A组患者sICAM-1水平最高,与B组及C组患者相比有统计学差异(P<0.01);②前三组各组内sICAM-1与FT3、FT4成直线相关关系,与TG、TM成直线相关关系;③GO炎性活动期患者sICAM-1与GO评分成正相关。结论:血清sICAM-1水平可作为反映GO活动性评判的免疫指标,长期监测sICAM-1可预示GD进展为临床活动性眼病的可能性。  相似文献   
4.
活动性结核标志物'H-多肽的实验与临床研究   总被引:2,自引:0,他引:2  
本题研究是经免疫学途径直接检测人体感染结核菌的情况,为现代结核病的实验诊断、临床监测、流行病调查提供了一个全新的检验指标。作者首先发现了一种仅存在于活动性结核病患者体液中的蛋白成份—活动性结核标志物(ActiveTuberculosisMark—ATM)1H—多肽;并为之创立了独特的检测方法,经四年多临床19460例样本调查中确定了ATM的临床价值。将ATM检测与OT皮试、酶联免疫ELISA、DNA探针、PCR基因扩增技术及典型病例组患者行X线计算机断层摄影(CT)、磁共振像(MRI)等多组对比试验中,实验与临床研究资料分析证明:ATM检测的总敏感度为86.06%、特异度96.24%、准确度93.45%、诊断效率为82.82%、批内CV1.2%、批间CV2.0%、P<0.05。经NMR光谱分析结构含有CCH2官能团。  相似文献   
5.
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   
6.
Summary An investigation was carried out on isolated cat's papillary muscle in order to study displacement effects upon the intensity and the time course of the contractile activity. Displacements occurring before or very early during a contractile cycle produce effects which can be entirely explained on the basis of the cardiac active length-tension relation. Displacements occurring later exhibit additional effects in so far as either stretches or releases induce a drop of contractile activation such that the course of the subsequent tension development is markedly below that of the same displacement applied earlier. In order to separate these effects from those based on the active length-tension correlation experiments were performed in which very short release-stretch or stretch-release operations were applied so that the muscle length was virtually the same at the beginning and at the end of the operation. The results obtained under these conditions can be summarized as follows.The extend to which contractile tension drops after a stretch-release or a release-stretch cycle has been applied depends upon (1) the stimulus intervention interval (2) the length change performed (3) the velocity of displacement during the intervention. It is not dependent on the initial muscle length. Increasing the extracellular Ca-concentration considerably reduces the displacement effects. The results are tentatively explained by assuming an internal feedback loop between a variable of the contractile machinary and the preceding mechanism of activation.This investigation was supported by the Deutsche Forschungsgemeinschaft (grant Ka 287, 1+3).  相似文献   
7.
Summary Autoregressive topographic EEG analysis was used to determine topographic EEGs of the total power in quiet and active sleep stages in 33 healthy premature infants of 34 to 40 weeks conceptional age. The developmental characteristics were also examined by simultaneously referring to the autoregressive pattern discrimination of topographic EEGs between different conceptional age groups in both sleep stages. Treating 10.24 seconds of EEG as one segment, the topographic EEG of 10 segments in each of the quiet and active sleep stages as well as their mean were obtained. In both sleep stages the results showed a small peak in total power in the frontal region and a large peak in the occipital region, but total power was greater in the quiet sleep. Total power decreased with increasing conceptional age. Topographic pattern discrimination between different conceptional age groups showed significant differences mainly in the frontal, temporal and occipital regions. It was concluded that regional differences in the development of EEG in premature infants could be clarified by means of topographic EEG analysis and the pattern discrimination method using the autoregressive model.This study was supported by a Scientific Research Grant (No. 02670450) from the Japanese Ministry of Education.  相似文献   
8.
The main purpose of the present study was twofold: (a) to assess the relationship between defensive hostility (high hostility/high defensiveness) and additional heart rate reactivity during active coping and (b) to determine if the construct of anger-out might lend additional, sensitivity to the predictive power of the defensive hostility model. Forty individuals were randomly assigned to complete a mental arithmetic task with or without the threat of shock. Participants also completed the Cook-Medley Hostility Inventory (Ho), the Marlowe-Crowne Social Desirability Scale (MC), and the Spielberger Anger Expression Scale. Defensive hostile subjects (high Ho/high MC) were significantly more reactive than any other subgroup. In addition, the combination of low Ho/high anger-out scores yielded a subgroup significantly less reactive than any other subgroup. These findings clarify the complex relationship of hostility and cardiovascular reactivity.  相似文献   
9.
Mid-log phase Leishmania donovani promastigotes accumulated 2-deoxy-d-glucose (2-DOG) via a carrier mediated transport system, maintaining an apparent Km of 24.4 μM and a Vmax of 3.12 nmol mg?1 protein min?1. d-Glucose but not l-glucose competitively inhibited the 2-DOG transport with an apparent Ki of 18.7 μM. Transport of 2-DOG was inhibited by 2,4-dinitrophenol and NaN3. The parasites maintained a 2-DOG gradient of at least 79 fold across the surface membrane, demonstrating the active nature of the transport system.  相似文献   
10.
用高价人抗HBs在人体内诱导产生抗HBs   总被引:2,自引:0,他引:2  
胡其乐  王泓 《免疫学杂志》1990,6(3):179-182
本文探讨用外源性人抗HBs在人体通过免疫网络诱导产生自身的抗HBs的可能性。志愿者经多次注射人高价抗HBs(Ab_1)后,体内产生了Ab_2,进而产生出特异性与Ab_1相同的Ab_3;当Ab_3水平升高时,Ab_2水平下降。此结果证实了人体内独特型网络的存在及其活跃的调节功能,表明用于被动免疫的人抗HBs在人体也能通过激活独特型网络产生主动免疫保护作用。此外,本文的结果还提示,注射人抗HBs后,人体内产生的Ab_2可模拟HBsAg,使常规的HBsAg检查出现假阳性结果。  相似文献   
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