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31.
Inflammation markers in relation to cognition in a healthy aging population   总被引:8,自引:0,他引:8  
The relation between serum inflammatory protein levels and cognitive performance was investigated in a healthy population.Individuals were tested during 6 years of follow-up. Serum concentrations of 10 inflammatory proteins were correlated to cognitive speed (Letter-Digit Coding Test, LDCT), attention and information processing (Stroop) and memory (Word Learning). Haptoglobin levels at baseline correlated negatively with cognitive performance on the Stroop and Word Learning Recall test over the 6 years follow-up period. C-reactive protein (CRP) levels at baseline correlated negatively with performance on the Word Learning tests over the 6 years follow-up period. Thus, relatively high concentrations of haptoglobin and C-reactive protein may be indicative for impaired cognitive performance.  相似文献   
32.
5-Flourouracil(5-FU) is one of well known anti-cancer drugs, but its toxicity in normal lymphocytes remains a major problem in chemotherapy. The eastern traditional drug, Bupleuri radix(BR), has been used for the treatment of liver diseases and contains series of triterpene saponins.  相似文献   
33.
The tuberomammillary nucleus (TM) located in the posterior part of the hypothalamus is the main source of neuronal histamine in the central nervous system. Recent work from our laboratories has indicated an involvement of the TM region in neuronal plasticity and reinforcement processes. In the present study, we investigated the effects of TM lesions on the performance of adult and aged Wistar rats in a set of learning tasks, which differed in terms of complexity and reward contingencies (habituation learning, inhibitory avoidance, discrimination learning, Morris water maze). An improvement was found in every test applied, indicating that TM lesions seem to generally enhance learning and memory capacities independent of the special demands of a given task. Age-related learning deficits were strongly diminished. Immunohistochemistry revealed that the excitotoxic lesions used to destroy the TM region led to a marked decrease in the number of histamine-positive neurons in the vicinity of the injection site, indicating an involvement of the brain histaminergic system in the observed behavioral changes. Received: 1 October 1996 / Accepted: 18 August 1997  相似文献   
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The Basso, Beattie and Bresnahan (BBB) locomotor rating scale is the most widely used open field test and has been accepted as a valid way to assess locomotor function after spinal cord contusion injury in the rat. A limitation within the BBB locomotor rating scale is the correct assessment of forelimb (FL)-hindlimb (HL) coordination. This limitation can have major implications for the final assessment of locomotor function. In the present study, we show an objective method to assess coordination based on the regularity index (RI), achieved through the use of the CatWalk method. The RI grades the degree of coordination as the result of the number of normal step sequence patterns multiplied by four and divided by the total amount of paw placements. Using the RI, single walkway crossings can be objectively analyzed on coordination. Integration of the CatWalk based coordination into the BBB scale indicates that objective analysis of coordination results in reliable and more sensitive assessment of locomotor function. This new method has been tested successfully in determination of positive effects of enriched housing on functional recovery after spinal cord injury (SCI).  相似文献   
36.
It has been postulated that the prefrontal cortices of schizophrenic patients have significant alterations in their interneuronal (neuropil) space. The present study re-examines this finding based on measurements of mean cell spacing within the cell minicolumn. The population studied consisted of 13 male schizophrenic patients (DSM-IV criteria) and 13 age-matched controls. Photomicrographs of Brodmann's areas 9, 4 (M1), 3b (S1), and 17 (V1) were analyzed with computerized image analysis to measure parameters of minicolumnar morphometry, i.e., columnarity index (CI), minicolumnar width (CW), dispersion of minicolumnar width (V(CW)), and mean interneuronal distance (MCS). The results indicate alterations in the mean cell spacing of schizophrenic patients according to both the lamina and cortical area examined. The lack of variation in the columnarity index argues in favor of a defect postdating the formation of the cell minicolumn.  相似文献   
37.

Background  

Magnetocardiography enables the precise determination of fetal cardiac time intervals (CTI) as early as the second trimester of pregnancy. It has been shown that fetal CTI change in course of gestation. The aim of this work was to investigate the dependency of fetal CTI on gestational age, gender and postnatal biometric data in a substantial sample of subjects during normal pregnancy.  相似文献   
38.
Previous studies in the literature have resulted in conflicting reports on the potential neurotoxicity of the beta-cleaved Alzheimer's disease C-terminal fragment (beta-CTF) of beta-amyloid precursor protein in vivo. To readdress this question by rigorous quantitative methods, we analyzed transgenic mice expressing human beta-CTF with the I45F mutation (SPA4CT) under control of the prion protein promoter by stereological techniques. The transgene was expressed in hippocampus and cortex in large pyramidal neurons and in dentate gyrus granule cells. Proteolytic processing of beta-CTF released Abeta. However, most of it remained uncleaved. Neurodegeneration was evaluated by investigating the numbers of hippocampal pyramidal and granule neurons, as well as the number of synaptophysin-immunopositive presynaptic boutons in the hippocampus of 15-month-old SPA4CT mice with design-based stereological techniques. The analyses showed that a fourfold higher expression of the transgene compared to murine APP levels had no effect on the numbers of both neurons and synaptophysin-immunopositive presynaptic boutons. These data implicate that expression of beta-CTF per se is not neurotoxic, and that other mechanisms are responsible for the neurotoxic events in Alzheimer's disease brain.  相似文献   
39.
The islands of Calleja in the rat brain stain brilliantly and stand out clearly using the NADPH-diaphorase histochemical staining. The 3-D structure of the Islands of Calleja was mapped in sagittal sections of young adult (3 months) and aged (28 months) animals. Contours were determined using a camera lucida method, and transferred to a computer equipped with an image analyzing system. Alignment of the sections using fixed anatomical anchers revealed that the islands of Calleja were one continuous structure at both ages studied. The structures varied between animals, and there was a pronounced left-right difference in the individual rats.  相似文献   
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