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61.
目的 观察阿托伐他汀对心肌梗死后大鼠基质金属蛋白酶(MMP)-2、微小RNA(miRNA,miR)-21表达的影响.方法 选取140只Wistar大鼠建立急性心肌梗死模型,分为假手术组、对照组、阿托伐他汀低剂量组和高剂量组,进行左室重量指数、心肌胶原容积分数、miRNA-21及MMP-2 mRNA表达测定.结果 阿托伐他汀治疗组左室重量指数、心肌胶原容积分数、梗死周边区miR-21 、MMP-2 mRNA的表达均降低(P<0.05);各组梗死周边区miR-21表达量与MMP-2 mRNA水平呈正相关(r对照组=0.611,P<0.05;r阿托伐他汀低剂量组=0.502,P<0.05;r阿托伐他汀低剂量组=0.541,P<0.05).结论 阿托伐他汀能降低梗死周边区MMP-2和miR-21的表达,发挥减轻心室重构的作用.  相似文献   
62.
目的 探讨高血压性脑出血颅内血肿清除术后并发癫痫发作的影响因素。方法 回顾性分析2011年3月至2018年7月开颅血肿清除术治疗的485例高血压性脑出血的临床资料。采用多因素logistic回归分析检验术后并发癫痫的危险因素。结果 485例中,术后发生癫痫62例(12.9%)。多因素logistic回归分析结果显示,血肿体积≥60 ml、血肿位于小脑、术后再出血、术后电解质紊乱、脑电图异常、术前C反应蛋白(CRP)水平升高、术前肿瘤坏死因子-α(TNF-α)水平升高、术前白细胞介素-6(IL-6)水平升高是术后并发癫痫发作的独立危险因素(P<0.05)。结论 高血压性脑出血开颅血肿清除术后癫痫发作发生率较高,对于血肿较大、血肿位于小脑、术后再出血、术后电解质紊乱、脑电图异常、术前CRP、TNF-α、IL-6水平升高的病人,应采取针对性措施预防术后癫痫发作。  相似文献   
63.

Objective

It was hypothesized that dopamine agonist administration and subthalamic nucleus (STN) lesion in the rat might have a synergistic effect on the neuronal activities of substantia nigra pars reticulata (SNpr) as observed in patients with Parkinson''s disease. The effects of SKF38393 (a D1 receptor agonist) and Quinpirole (a D2 receptor agonist) were compared in parkinsonian rat models with 6- hydroxydopamine (6-OHDA) after STN lesion.

Methods

SKF38393 and Quinpirole were consecutively injected intrastriatally. SNpr was microrecorded to ascertain the activity of the basal ganglia output structure. The effect of SKF38393 or Quinpirole injection on the firing rate and firing patterns of SNpr was investigated in medial forebrain bundle (MFB) lesioned rats and in MFB+STN lesioned rats.

Results

The administration of SKF38393 decreased SNpr neuronal firing rates and the percentage of burst neurons in the MFB lesioned rats, but did not alter them in MFB+STN lesioned rats. The administration ofQuinpirole significantly decreased the spontaneous firing rate in the MFB lesioned rats. However, after an additional STN lesion, it increased the percentage of burst neurons.

Conclusion

This study demonstrated that dopamine agonists and STN lesion decreased the hyperactive firing rate and the percentage of burst neurons of SNpr neurons in 6-OHDA lesioned rats, respectively. Quinpirole with STN lesion increased a percentage of burst neurons. To clear the exact interactive mechanism of D1 and D2 agonist and the corresponding location, it should be followed a study using a nonselective dopamine agonist and D1, D2 selective antagonist.  相似文献   
64.
This paper provides the practical part of a procedure for endoscopic endonasal transsphenoidal resection of pituitary tumors. The authors have presently gained experience with about 400 endoscopic endonasal transsphenoidal operations. The advantages of endoscopic surgery include the wide vision field of an operative site under good illumination. The endoscopic intervention provides a possibility of extracting not only endo-, but also paracellular portions of a tumor under direct visual control, which can be rarely done during a standard microscopic transnasal operation. The paper gives recommendations on the equipment of an operating suite and anesthetic maintenance. It also describes surgical stages and postoperative management of patients.  相似文献   
65.
Changes in social and emotional behaviour have been consistently observed in patients with traumatic brain injury. These changes are associated with emotion recognition deficits which represent one of the major barriers to a successful familiar and social reintegration. In the present study, 32 patients with traumatic brain injury, involving the frontal lobe, and 41 ageand education-matched healthy controls were analyzed. A Go/No-Go task was designed, where each participant had to recognize faces representing three social emotions (arrogance, guilt and jealousy). Results suggested that ability to recognize two social emotions (arrogance and jealousy) was significantly reduced in patients with traumatic brain injury, indicating frontal lesion can reduce emotion recognition ability. In addition, the analysis of the results for hemispheric lesion location (right, left or bilateral) suggested the bilateral lesion sub-group showed a lower accuracy on all social emotions.  相似文献   
66.
Early-onset bipolar disorder is an impairing condition that is strongly associated with genetic inheritance. Neurocognitive deficits are core traits of this disorder which seem to be present in both young and adult forms. Deficits in verbal memory and attention are persistent within euthymic phases in bipolar adults, adolescents, and children. In younger samples, including type I or II and not otherwise specified patients, executive functions are not widely impaired and the existence of visual-spatial deficits remains unclear. The main aim of this study was to compare the neurocognitive performance in young stabilized type I or II bipolar patients and healthy controls. Fifteen medicated adolescents with bipolar disorder and 15 healthy adolescents, matched in age and gender, were compared on visual-spatial skills (reasoning, memory, visual–motor accuracy) and executive functioning (attention and working memory, set-shifting, inhibition) using t-tests and MANCOVA. Correcting for verbal competence, MANCOVA showed that patients performed significantly worse than controls in letters and numbers sequencing (P = 0.003), copy (P < 0.001) and immediate recall (P = 0.007) of the Rey Complex Figure Test, interference of the Stroop Color-Word Test (P = 0.007) and non-perseverative errors on the Wisconsin Card Sorting Test (P = 0.038). Impaired cognitive performance was found in young bipolar patients in working memory, visual-motor skills, and inhibitory control.  相似文献   
67.
Semantic verbal fluency tasks are commonly used in neuropsychological assessment. Investigations of the influence of level of literacy have not yielded consistent results in the literature. This prompted us to investigate the ecological relevance of task specifics, in particular, the choice of semantic criteria used. Two groups of literate and illiterate subjects were compared on two verbal fluency tasks using different semantic criteria. The performance on a food criterion (supermarket fluency task), considered more ecologically relevant for the two literacy groups, and an animal criterion (animal fluency task) were compared. The data were analysed using both quantitative and qualitative measures. The quantitative analysis indicated that the two literacy groups performed equally well on the supermarket fluency task. In contrast, results differed significantly during the animal fluency task. The qualitative analyses indicated differences between groups related to the strategies used, especially with respect to the animal fluency task. The overall results suggest that there is not a substantial difference between literate and illiterate subjects related to the fundamental workings of semantic memory. However, there is indication that the content of semantic memory reflects differences in shared cultural background--in other words, formal education--, as indicated by the significant interaction between level of literacy and semantic criterion.  相似文献   
68.
The growth factor erythropoietin (EPO) and erythropoietin receptors (EPOR) are expressed in the nervous system. Neuronal expression of EPO and EPOR peaks during brain development and is upregulated in the adult brain after injury. Peripherally administered EPO, and at least some of its variants, cross the blood-brain barrier, stimulate neurogenesis, neuronal differentiation, and activate brain neurotrophic, anti-apoptotic, anti-oxidant and anti-inflammatory signaling. These mechanisms underlie their tissue protective effects in nervous system disorders. As the tissue protective functions of EPO can be separated from its stimulatory action on hematopoiesis, novel EPO derivatives and mimetics, such as asialo-EPO and carbamoylated EPO have been developed. While the therapeutic potential of the novel EPO derivatives continues to be characterized in preclinical studies, the experimental findings in support for the use of recombinant human (rh)EPO in human brain disease have already been translated to clinical studies in acute ischemic stroke, chronic schizophrenia, and chronic progressive multiple sclerosis. In this review article, we assess the studies on EPO and, in particular, on its structural or functional variants in experimental models of nervous system disorders, and we provide a short overview of the completed and ongoing clinical studies testing EPO as neuroprotective/neuroregenerative treatment option in neuropsychiatric disease.  相似文献   
69.
70.
The origins of cerebral abnormalities in psychotic patients remain unknown. Dermatoglyphics are suitable markers of prenatal injury due to their fetal ontogenesis and their susceptibility to some of the factors that also affect cerebral development. In a previous study, positive associations between brain volumetric measures and a dermatoglyphic marker, the ab-ridge count, were reported. The present study is an attempt to replicate that finding in an independent sample. Magnetic resonance imaging (MRI) scans and dermatoglyphic measures were available for 29 schizophrenia patients (Research Diagnostic Criteria [RDC] criteria) and 26 unrelated healthy controls. The images were processed using an automated procedure, yielding volumes of total grey matter, white matter, cerebrospinal fluid (CSF), and total brain volume. The ab-ridge count was not positively associated with brain volumes in either patients or controls. The present findings do not support the hypothesis that the changes in brain volume seen in patients with schizophrenia are of prenatal origin.  相似文献   
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