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Burbaeva GSh Boksha IS Turishcheva MS Savushkina OK Tereshkina EB Vorob'eva EA 《Vestnik Rossi?sko? akademii meditsinskikh nauk / Rossi?skaia akademiia meditsinskikh nauk》2001,(7):34-37
There is strong evidence for the involvement of the neurotransmitter glutamate system in the pathogenesis of Alzheimer's disease and schizophrenia. In these mental diseases, the brain shows changes in the levels of glutamate and in the function and expression of its transporters and receptors. Since the levels of glutamate are largely determined by the rate of its metabolism, the changes of its concentrations may be associated with dysfunctions of appropriate enzymes. Actually, disturbances of glutamate metabolic enzymes, such as glutaminase, glutamate decarboxylase, and glutamine synthetase were detected in the brain of patients with Alzheimer's disease. The alterations in the expression of glutamine synthetase, glutamine synthetase-like protein, and three isoenzymes of glutamate dehydrogenase in the frontal cortex of patients with schizophrenia suggest that there are impaired glutamate metabolism in this mental disease and Alzheimer's disease. 相似文献
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Improved PCR for detection of the highly leukotoxic JP2 clone of Actinobacillus actinomycetemcomitans in subgingival plaque samples
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The JP2 clone of Actinobacillus actinomycetemcomitans is associated with early-onset periodontitis in certain ethnic populations of African origin. Here, we describe and evaluate a set of primers for PCR to assay for the presence of A. actinomycetemcomitans and to discriminate between JP2-like strains and other genotypes in subgingival plaque samples. 相似文献
4.
Cromwell HC Hassani OK Schultz W 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,162(4):520-525
Rewards are often not only valued according to their physical characteristics but also relative to other available rewards. The striatum (caudate nucleus, putamen, ventral striatum including nucleus accumbens) is involved in the organization of movement and the processing of reward information. We studied the activity of single striatal neurons in macaques that were presented with different combinations of two rewards. We found in nearly half of the investigated neurons that the processing for one reward shifted, relative to the other rewards that were available in a given trial block. The relative reward processing concerned all forms of striatal activity related to reward-predicting visual stimuli, arm movements and reception of rewards. The observed changes may provide a neural basis for the known shifts in valuation of rewarding outcomes relative to known references. 相似文献
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小儿慢性乙型肝炎外周血T细胞亚群和临床病理关系的研究 总被引:7,自引:0,他引:7
目的 探讨小儿慢性乙型肝炎细胞免疫功能与临床、病理的关系 ,了解其间的相关性。方法 研究对象为确诊的 94例 12岁以内慢性乙型肝炎住院患儿。常规检测血T细胞亚群等、血丙氨酸转氨酶 (ALT)水平、病毒学指标 ,并进行腹部B超、肝脏病理学检查。结果 有活动性肝脏病理炎症者CD4 CD8 升高 (P <0 0 5 ) ;女性比男性CD4 降低差异有非常显著意义 (P <0 0 1)、CD8 升高差异有显著意义 (P <0 0 5 )、CD4 CD8 降低差异有非常显著意义 (P <0 0 1) ;T淋巴细胞的异常改变与HBVDNA、PTA以及脾脏大小关系不明显。而各项观察的临床、病理指标与CD3 T淋巴细胞、B淋巴细胞均无明显相关性。结论 小儿慢性乙型肝炎患者机体存在细胞免疫功能失衡 ,其相关性表现在肝脏炎症损伤严重程度与T淋巴细胞功能的损伤有明显的相关性 ,女性对HBV的T淋巴细胞反应比男性更有利于清除HBV ,其预后及对抗病毒和免疫调节治疗反应较好。 相似文献
6.
Ahn HW Shin WG Park KJ Suh OK Choi JH 《Research communications in molecular pathology and pharmacology》1999,105(1-2):105-113
Theophylline has been widely used to treat apnea of premature neonates. The purpose of this study was to compare the pharmacokinetic parameters of theophylline and caffeine after intravenous administration of aminophylline to seven Korean low-birthweight neonates with apnea to those in other countries. The serum concentrations of theophylline and caffeine were measured simultaneously by high-performance liquid-chromatography (HPLC). The mean (+/- S.E.M.) birth weight and gestational period were 1190 +/- 253 g and 31.5 +/- 1.99 weeks, respectively. The mean (+/- S.E.M.) theophylline maintenance dosage was 1.28 +/- 0.15 mg/kg (given as equivalent aminophylline solution) every six hours. The mean (+/- S.E.M.) volume of distribution, 0.937 +/- 0.232 l/kg, elimination rate constant, 0.0249 +/- 0.0095/h, elimination half-life, 32.1 +/- 12.1 h, and total body clearance, 21.7 +/- 6.18 ml/h/kg, of theophylline in Korean premature neonates were comparable to the values of neonates in other countries. For caffeine, the mean (+/- S.E.M.) elimination half-life was 95.1 +/- 25.4 h and the elimination rate constant was 0.0079 +/- 0.0024/h. The mean (+/- S.E.M.) serum concentrations of theophylline and caffeine on the sixth day after aminophylline infusion were 10.4 +/- 2.28 microg/ml (range, 6.38-13.4 microg/ml) and 2.94 +/- 0.98 microg/ml (range, 1.80-4.44 microg/ml), respectively. The mean (+/- S.E.M.) caffeine to theophylline concentration ratio on the day after discontinuation of aminophylline infusion was 0.71 +/- 0.23 (range, 0.39-1.03). 相似文献
7.
To assess the long-term risk of facial nerve dysfunction after unilateral acoustic tumor stereotactic radiosurgery, we retrospectively analyzed our initial experience in 98 unilateral acoustic tumor patients who were evaluated at least 2 years after treatment. This observation interval permits an analysis of both the risk of onset and the potential for recovery of facial nerve function. The overall risk of developing any degree of delayed transient or permanent postoperative facial neuropathy was 21.4% (21 of 98 patients). Only one patient undergoing radiosurgery alone had poor residual facial nerve dysfunction worse than House-Brackmann grade III. Normal facial nerve function (House-Brackmann grade 1) was preserved in 95% of patients with small tumors (10 mm or less petrous-pons dimension) and in 90% of patients who had useful hearing and normal facial function preoperatively. Normal facial function was preserved in all patients with intracanalicular acoustic tumors. The risk of delayed facial neuropathy was reduced by performing radiosurgery when tumors were small (1000 mm(3) or less), by enclosing the tumor within the 50% isodose volume, by using multiple small radiation isocenters, and by detailed identification of the tumor volume using stereotactic magnetic resonance imaging. 相似文献
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PURPOSE: To determine if any of 8 categorical clinical variables can be used to select patients and improve the yield of a screening program for severe carotid stenosis (> or = 80%) in elective cardiac surgery patients. METHODS: A prospective cohort analysis of 200 consecutive patients prior to elective cardiac surgery for the following variables: age, gender, smoking carotid bruit, peripheral vascular disease, hyperlipidaemia, previous neurologic symptoms and diabetes mellitus. All patients were subsequently screened with carotid duplex scanning for the presence of severe carotid stenosis. Positive scans were confirmed by angiography. RESULTS: Sixteen patients (8%) were identified with severe carotid stenosis. Univariate analysis identified three variables that increase risk for carotid stenosis: carotid bruit (relative risk (RR)=16.4, 5.4-57.6 95% confidence interval, p<0.001), neurological history (RR=10.3, 3.9-23.2, p<0.001) and peripheral vascular disease (RR=5.3, 1.9-14.9, p<0.001). Stepwise logistic regression analysis identified previous neurologic history and carotid bruit as independent predictors of stenosis. If screening for carotid stenosis was limited to patients with these two variables, then 37 (18.5% of total) patients would have been screened. Fourteen of these 37 (37.8%) had a severe carotid stenosis. Two patients with stenosis (12.5% of those with carotid stenosis, 1% of total patient population) would not have been screened. CONCLUSIONS: Clinical variables can be used to improve the yield of a preoperative screening program for carotid stenosis. 相似文献
10.
Long (for more than 17 years) therapy of 2331 patients (3122 eyes) with vascular conditions of the fundus oculi by a retinotropic drug solcoseryl showed its high efficacy as a monotherapy and in complex with other traditional and symptomatic treatments. Solcoseryl improved the visual function and hemodynamics of retinal vessels, promoted a more stable and longer stabilization of the treatment results, and accelerated the rehabilitation of patients. 相似文献