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J. Richard Hanley Lyndsey Nickels 《Cortex; a journal devoted to the study of the nervous system and behavior》2009,45(6):784-790
In this paper, we investigate the claim that although the same lexical units are involved in speech production and comprehension, there are separate input and output phoneme layers (Foygel and Dell, 2000). Data from a case series of aphasic patients are used to test this claim by examining the relationship between performance on a test of picture naming and performance on tests of phonological input. Estimates of each patient's semantic-lexical and phonological impairments in speech production were derived from Foygel and Dell's computational model of picture naming. It was found that the strength of the semantic-lexical impairments in speech production was significantly correlated with performance on auditory comprehension tests. This finding is consistent with the claim that the same lexical units are involved in speech comprehension and production. Conversely, the correlations between the strength of the phonological lesions in speech production and performance on tests of phonological input were non-significant, consistent with Foygel and Dell's claim that there are distinct input and output phoneme layers. 相似文献
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目的:观察喉罩全麻下行颈动脉狭窄的造影诊断及介入治疗术的临床效果。方法:择期DSA下颈动脉狭窄患者23例,年龄42-78岁,无明显肺部疾患及喉罩禁忌症患者,异丙酚(Pmpofol)泵入静脉全麻下插入喉罩完成手术,观察其不同时段的BP(MAP)、SpO2、HR、ECG(ST-Ⅱ)。结果:各时段的BP(MAP)、Sp02、HR、ECG(ST-Ⅱ)比较无显著性差异。结论:喉罩全麻在行颈动脉狭窄的造影诊断及介入治疗术的临床效果是肯定的。喉罩全麻颈动脉狭窄造影介入治疗 相似文献
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In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V. 相似文献
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Mana Ichimura Koichi Hiratsuka Naomi Ogura Tadahiko Utsunomiya Hiroyuki Sakamaki Toshirou Kondoh Yoshimitsu Abiko Shigeo Otake Masafumi Yamamoto 《Journal of oral pathology & medicine》2006,35(3):167-174
BACKGROUND: To understand the immunopathological features of oral lichen planus (OLP), we analyzed the expression of chemokines in the epithelial cell layers. Methods: Epithelia from OLP or healthy gingiva were collected by laser microdissection. The chemokine and chemokine receptor expressions in the epithelia were analyzed by DNA microarray. RESULTS: High levels of MIP-3alpha/LARC/CCL20 and its receptor CCR6 were expressed in the lesional epithelia. Furthermore, DC-CK1/CCL18, ELC/CCL19, SDF-1/CXCL12 and CXCR4 expressions were also increased. Immunohistologial analysis showed that high numbers of Langerhans cells (LCs) were present in the epithelia of OLP. Lesional epithelia also expressed high levels of the ligands specific for CXCR3 (e.g. MIG/CXCL9, IP-10/CXCL10 and I-TAC/CXCL11) and CCR5 (e.g. RANTES/CCL5). CONCLUSIONS: Infiltration of LCs is orchestrated by CCR6. Further, LCs residing in the lesional epithelia may be a mature phenotype. Moreover, infiltration of T cells in OLP could be mediated by signaling pathways through CXCR3 and CCR5. 相似文献
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Thomas Lanspa Dennis J Esterbrooks Mark A Williams 《Catheterization and cardiovascular interventions》2005,64(2):223-226
Stenting of the carotid artery is usually performed either to prevent an acute neurologic event or to treat episodes of recurrent transient ischemic attacks. Occasionally, it may be performed for other indications. We describe the case of a patient with prior coronary artery bypass grafting using a left internal mammary arterial graft, in addition to left carotid artery to left subclavian artery bypass for symptomatic left subclavian stenosis, who subsequently underwent left common carotid artery stenting to relieve anginal symptoms. 相似文献
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Jong-Moon Lee Kun-Woo Park Woo-Keun Seo Moon Ho Park Changsu Han Inho Jo Sangmee Ahn Jo 《Movement disorders》2007,22(16):2446-2449
There have been a few studies and inconsistent results regarding the coincidence of Parkinson's disease (PD) and atherosclerotic diseases, such as cerebrovascular disease. Carotid intima-media thickness (IMT) is a known marker for subclinical atherosclerosis. The aim of this study was to investigate the carotid IMT between PD patients and controls. We studied 43 patients with PD and 86 matched controls. The carotid IMT in PD patients was significantly smaller than in controls (0.796 +/- 0.179 mm vs. 0.913 +/- 0.237 mm, P < 0.05). In multivariate analysis, the carotid IMT was inversely associated with the duration of levodopa medication and the severity of PD. These results suggest that PD patients have a lower risk of atherosclerosis. 相似文献
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Summary A patient with severe, recurrent posterior epistaxis was shown at angiography to have an aneurysm of the petrous portion of the internal carotid artery (ICA). Since childhood, she had had pain related to eustachian tube blockage by the aneurysm. An endovascular balloon embolization of the aneurysm was successful with preservation of the parent artery. The treatment resulted in resolution of the symtpoms. The report confirms the usefulness of an angiographic protocol in evaluating vascular problems. 相似文献