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971.
OBJECTIVE: Multiple system atrophy (MSA), progressive supranuclear palsy (PSP), and corticobasal-ganglionic degeneration (CBGD) are all clinically characterized by an akinetic-rigid syndrome together with a variety of additional signs. We hypothesised that these atypical parkinsonian syndromes (APS) will show distinctive patterns in their motor output upon transcranial magnetic stimulation (TMS) due to their different underlying anatomico-functional deficits. METHODS: We performed single and paired-pulse TMS and assessed inhibitory and excitatory response parameters from the first dorsal interosseus muscles in 13 patients with MSA, 18 with PSP, 13 with CBGD, 15 patients with Parkinson's disease and 17 healthy subjects. RESULTS: PSP and MSA patients had significantly enlarged response amplitudes at rest, reduced intracortical inhibition (ICI) and prolonged ipsi- and contralateral silent periods, whereas CBGD patients showed significantly increased motor thresholds, smaller response amplitudes at rest, shortened contralateral silent period, reduced transcallosal inhibition and a reduced ICI. In 22% of APS patients ipsilateral motor responses occurred in upper limb muscles irrespective of the underlying disease. CONCLUSIONS: Our results indicate that motor cortex disinhibition is predominant in patients with PSP and MSA. In CBGD more severe neuronal cell loss in the motor cortex itself may lead to hypoexcitability of corticospinal and transcallosal pathways.  相似文献   
972.
973.
974.
BACKGROUND CONTEXT: Intraradicular lumbar disc herniation is rare, having been reported to date in only three postoperative patients. The diagnosis is typically made intraoperatively. PURPOSE: To report a fourth case of intraradicular disc herniation, to emphasize its radiological characteristics and operative findings. STUDY DESIGN: Case report. PATIENT SAMPLE: A 41-year-old female. METHODS: Retrospective case review. RESULTS: The patient underwent a second operation and intraradicular disc fragment was removed. She was completely well at her 9-month check up. CONCLUSIONS: The diagnosis, mechanism, and surgical treatment of intraradicular lumbar disc herniation are reviewed. The round shape of the sequestrated fragment, as seen on magnetic resonance imaging, may help to establish the correct diagnosis.  相似文献   
975.
PURPOSE: To report the first successful endovascular repair of a non-aneurysmal aortic rupture due to periaortic tumour regression. CASE REPORT: A 58-year-old man developed spontaneous infrarenal aortic rupture following chemotherapy which led to regression of a periaortic mesothelioma that had been diagnosed during explorative laparotomy 11 months earlier. Stent-graft placement was performed with intentional conversion of a bifurcated (Zenith, COOK) into an aorto-uni-iliac system. No complications were encountered during a 40 months follow-up. CONCLUSION: Endovascular repair should be considered as a treatment option in non-aneurysmal aortic rupture.  相似文献   
976.
977.
BACKGROUND: Oxytocin is known to reduce anxiety and stress in social interactions as well as to modulate approach behavior. Recent studies suggest that the amygdala might be the primary neuronal basis for these effects. METHODS: In a functional magnetic resonance imaging study using a double-blind, placebo-controlled within-subject design, we measured neural responses to fearful, angry, and happy facial expressions after intranasal application of 24 IU oxytocin compared with placebo. RESULTS: Oxytocin reduced right-sided amygdala responses to all three face categories even when the emotional content of the presented face was not evaluated explicitly. Exploratory whole brain analysis revealed modulatory effects in prefrontal and temporal areas as well as in the brainstem. CONCLUSIONS: Results suggest a modulatory role of oxytocin on amygdala responses to facial expressions irrespective of their valence. Reduction of amygdala activity to positive and negative stimuli might reflect reduced uncertainty about the predictive value of a social stimulus and thereby facilitates social approach behavior.  相似文献   
978.
A 41-year-old male patient presented with veiled vision which had appeared only a few hours previously. Funduscopy revealed a retinal edema due to venous stasis retinopathy. A previous history was unknown except for an uncorrected arterial hypertension. A retinal vein thrombosis and macula edema developed in the affected eye. An antiphospholipid antibody syndrome was diagnosed which was treated with anticoagulants.  相似文献   
979.
Abstract Alzheimer's disease (AD) is defined pathologically by the presence of β-amyloid plaques, neurofibrillary tangles and extensive neuronal loss. Evidence indicates that increased DNA damage may contribute to neuronal loss in AD. Recently, it has been shown that in AD neurons have a reduced capacity for some types of DNA repair. Polymorphisms in DNA repair genes may be associated with differences in repair efficiency of DNA damage. Variants of several DNA repair genes, including the base excision repair gene XRCC1, have been described previously. We hypothesised that Arg194Trp polymorphism of XRCC1 gene may contribute to genetic susceptibility for AD. In order to test this hypothesis, we investigated Arg194Trp polymorphism at the XRCC1 gene in the DNA samples of 98 patients with AD and 95 healthy subjects. The frequency of the Trp allele was more pronounced among cases (11.2%) compared with controls (5.8%). On combining the homozygous and heterozygous variants of each codon, the variants seemed to be at twofold risk of AD, although the risk estimates were not statistically significant (OR=1.95, 95% CI 0.88–4.34, p=0.09). In addition, the 194Trp allele revealed a borderline significance (OR=2.05, 95% CI 0.96–4.37, p=0.056). According to our results, it may be speculated that the polymorphic variants of XRCC1 codon 194 have a role in the development of AD.  相似文献   
980.
骨肉瘤细胞特异性结合短肽的筛选   总被引:2,自引:1,他引:1  
目的:获得与骨肉瘤细胞株os-732特异结合的短肽,作为骨肉瘤靶向治疗的先导化合物。方法:以骨肉瘤细胞os-732为靶细胞,成骨细胞为吸附细胞对噬菌体12肽库进行差减筛选,用细胞ELISA、免疫组化鉴定阳性噬菌体克隆并测序。结果:经三轮筛选,从随机挑选的20个噬菌体克隆中得到9个特异性与骨肉瘤细胞os-732结合,而不与正常成骨细胞结合的阳性克隆。但其氨基酸序列无同源性。结论:得到多个序列不同的特异性结合骨肉瘤的噬菌体克隆,提示骨肉瘤细胞表面结构复杂,具多个骨肉瘤抗原表位。本实验获得的短肽具有一定的亲合力和肿瘤特异性,为针对不同位点的靶向药物设计提供了实验依据。  相似文献   
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