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961.
Victoria P. Shuster 《Cognitive neuropsychology》2018,35(7):385-401
We report on an English-speaking, aphasic individual (RB) with a spelling deficit more severely affecting orthographically irregular words for which phonologically plausible errors (PPEs) were produced. PPEs were observed for all word forms, with the exception of inflectional suffixes, despite the irregular sound-print mappings of many inflectional suffixes (e.g., walked → /w?kt/). RB's pattern replicates that reported in Badecker, Rapp, and Caramazza (Badecker, W., Rapp, B., &; Caramazza, A. (1996). Lexical Morphology and the Two Orthographic Routes. Cognitive Neuropsychology, 13, 161–176). We extended their investigation by examining RB's spelling of derived words and found a selective deficit for derived words compared to inflected words in writing. This selective deficit did not appear to reflect differences in morphological transparency or suffix frequencies that exist between inflection and derivation. This is the first evidence that distinct neural mechanisms support inflection and derivation in spelling. 相似文献
962.
963.
Electrophoretic determination of the myosin/actin ratio in the diagnosis of critical illness myopathy 总被引:2,自引:0,他引:2
Objective To develop a rapid method to quantify myosin in muscle biopsy specimens from patients with critical illness myopathy (CIM).Design Percutaneous muscle biopsy specimens at different stages of CIM were examined by light microscopy and transmission electron microscopy (TEM) and by horizontal pore gradient SDS electrophoresis (SDS-PAGE). The myosin/actin ratio was calculated densitometrically. Neurophysiological examinations were performed at various times during the course of CIM.Setting All patients were treated in intensive care units at Karolinska Hospital.Patients and participants We studied 11 patients with CIM, 5 patients with axonal neuropathies, and 42 control individuals.Measurements and results The histopathological changes included in all cases muscle fiber atrophy, degeneration, regeneration, nuclear changes, and reduction in myofibrillar ATPase activity in both type I and II fibers. In severely affected muscles fiber type differentiation was lost. On TEM preferential loss of thick filaments was the dominant finding. In some patients changes were present only in parts of the specimen. The neurophysiological examinations indicated myopathy in five patients and combined myopathy and neuropathy in five and suggested neuropathy in one. The SDS-pore PAGE used showed a technical variation of 4–5%. Quantitative results were obtained within 1 day and night. The mean value of the myosin/actin ratio in controls was 1.37±0.21 and in CIM patients 0.37±0.17, without overlapping with the control values.Conclusions Considering the diagnostic difficulty using morphological and neurophysiological methods, especially in early stages of CIM, we suggest including SDS-pore PAGE to determine the myosin/actin ratio for rapid diagnosis of CIM.This work was supported by grants from the Swedish Medical Research Council (nos. 07121, 03875) and the Karolinska Institute. 相似文献
964.
Summary Supernatant media from cultured human mononuclear blood leukocytes (MCCM) induced morphological changes in normal human synovial fibroblasts in culture, including the formation of cells with a dendritic or stellate morphology and, less frequently, cells with a striking fenestrated appearance. These changes were fully reversed within 1 h of removing the MCCM. They were inhibited by indomethacin, the glucocorticoids hydrocortisone, prednisolone and dexamethasone, and by colcemid, but not by actinomycin D and only weakly by cycloheximide. The morphological responses to MCCM could be reproduced by MCCM fractions containing interleukin 1-like activity and by purified forms of human interleukin 1 (IL-1), including monocyte-derived IL-1 and recombinant IL-1. These responses were also inhibited by indomethacin, indicating a link with prostanoid production. However, the morphological responses were not related to the stimulation of plasminogen activator activity due to MCCM, MCCM fractions, or IL-1. 相似文献
965.
966.
GMA保存血小板的实验研究 总被引:3,自引:1,他引:2
目的:探讨葡萄糖甘露醇腺嘌呤(GMA)作为添加剂对血小板的保存效果。方法:将GMA替代血浆制备的浓缩血小板(GMA-PC)和以ACD血浆为介质的浓缩血小板(ACD-PC)置22℃水平摇箱内保存,于各时间段取样测定有关指标。结果:两组PC的血小板低渗休克反应和以ADP诱导的血小板聚集率随保存时间的延长平行降低,差异无显著性(P> 0.05),在保存120h 期间,GMA-PC的乳酸脱氢酶释放量低于ACD- PC,前者的形态积分则显著高于后者,提示用GMA 保存的血小板其形态和细胞膜的完整性优于用ACD血浆保存的血小板。结论:初步证实用GMA替代血浆制备和保存浓缩血小板具有可行性 相似文献
967.
周围神经卡压损伤引起神经形态学变化的实验研究 总被引:7,自引:0,他引:7
目的:探讨周围神经卡压损伤后组织学改变与卡压时间的关系。方法:60只SD大鼠随机等分为4组(n=15),其中45只制备成神经卡压模型,A组:神经卡压1周后去除硅胶管;B组:神经卡压2周后去除硅胶管;C组:神经卡压3周后去除硅胶管。D组:只分离神经不进行卡压。各组分别于去除卡压后不同时间取材进行组织形态学观察。结果:各组神经卡压区域均发生不同程度的轴突肿胀和阶段性脱髓鞘改变,卡压时间越长病理变化越重。卡压松解后1-5周,A组卡压区域和远端的脱髓鞘改变与B、C组相比明显减轻。结论:周围神经卡压损伤程度与卡压时间成正比,及早去除卡压有利于损伤神经再生与修复。 相似文献
968.
目的 评价创伤性尿道狭窄术后吻合口形态超声诊断的可靠性。方法 对68例创伤性尿道狭窄术后排尿困难者尿道吻合口形态进行超声观察,并与再次手术结果对照。结果 尿道吻合口形态表现共4种,即狭窄疤痕形成(43例)、假道(12例)、尿道活瓣(4例)和狭窄合并关闭不全(9例)。超声形态表现类型和定位诊断均经手术证实。超声对手术吻合口狭窄疤痕长度和深度估测的相关系数γ分别为0.97,0.86,P<0.01。结论 尿道超声成像是评价尿道狭窄术后吻合口形态可靠的诊断方法,有助于指导术后排尿困难病例的临床正确处理。 相似文献
969.
体外培养的新生大鼠成骨细胞形态及功能的时相性变化 总被引:1,自引:0,他引:1
目的:探索大鼠成骨细胞(OB)在体外不同时间的形态及功能变化。方法:在为期28天的细胞培养中动态观察了新生大鼠头盖骨OB的活细胞形态变化,并与其皮肤成纤维细胞(FB)的形态变化作了比较,测定了OB中I型原胶原羧基端前肽(PICP),骨钙素(BGP)和碱性磷酸酶(ALP)的表达量变化。结果:OB与FB在早期散在分布时形态相似,汇合以后两者逐渐出现差异,OB在28天才可用Von Kossa法染到明显钙盐沉着;PICP,BGP分别于初始植入后第7,19天有表达高峰,ALP在12-16天和≥28天有两个表达高峰。结论:体外培养的大鼠OB形态及功能呈动态变化并具有高度趋同性。 相似文献
970.
Using retrograde HRP labeling from the optic nerve (ON) or optic tectum (OT), we have visualized large ganglion cells (LGCs) in wholemounted retinas of the teleost Pholidapus dybowskii and studied their morphology and spatial properties. In all, three LGC types were distinguished. In a previous paper, detailed data were provided on one type, biplexiform cells [Pushchin, I. I., & Kondrashev, S. L. (2003). Biplexiform ganglion cells in the retina of the perciform fish Pholidapus dybowskii revealed by HRP labeling from the optic nerve and optic tectum. Vision Research, 43, 1117-1133]. Here, we present data on the other two confirmed types, alpha(a) and alpha(ab) cells. The types differed in the level of dendrite stratification, dendrite arborization pattern, dendritic field size, and other features, and formed in the retina significantly non-random, spatially independent mosaics. Both types were labeled from the OT, indicating their participation in OT-mediated visual reactions. The comparison of spatial properties of alpha(a) and alpha(ab) mosaics labeled from the ON and OT suggests that the OT is the major or one of the major projection areas of both types. We also describe the morphology of cells resembling alpha(c) cells of other fishes, which were only labeled from the ON. The LGC types presently revealed were similar in their morphology to LGCs found in other teleosts supporting the hypothesis of LGC homology across the teleost lineage. 相似文献