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11.
The cerebrospinal fluid (CSF) transferrin/Tau proteins were studied by two-dimensional polyacrylamide gel electrophoresis (2D) followed by immunoblotting and by agarose isoelectrofocusing (IEF), and subsequent double immunofixation, peroxidase staining and Avidin-Biotin Complex (ABC) amplification. The pattern of the Tau protein was similar but not equal to that of the transferrin (Tf). When a genetic variant of Tf was present in the serum, the same variant was also observed in the corresponding CSF Tf and in the Tau fraction. After neuraminidase treatment, both serum and CSF Tf moved to the Tau position on IEF and 2D. On 2D, no desialized precursors of the Tau proteins were detected, whereas the Tf precursors were always detected. No synthesis of the Tau globulin in the brain can, therefore, be inferred. In CSF not treated with neuraminidase, Tf is the only sialoglycoprotein clearly desialized, showing that the Tau fraction cannot be generated by neuraminidase action at CSF level. In fact, the treatment of serum and CSF proteins with neuraminidase produced a clear shift in the isoelectric mobility of all sialoglycoproteins. We clearly demonstrate that the Tau globulin is the result of neuraminidase activity not located in the CSF compartment. We suggest that Tf could be desialized by the action of neuraminidase at the brain level and then be "washed" into the CSF. Brain utilization of Tf, meeting the brain iron requirement, seems likely.  相似文献   
12.
用苯酚、苯酐和水合肼合成了4-(4-羟苯基)-2,3-二氮杂萘酮-1,并与双酚-A和二苯甲酮聚合,得到含双酚-A和杂环结构的聚醚酮聚合物。用FT-IR、^13C-NMR、DSC、TGA和DMA等方法对聚合物进行了表征。结果表明,这种可溶性的非晶态聚合物有较高的Tg和很高的耐热温度,Tg随聚合物的组成不同而变化(158-224℃),5%热失重温度为444-541℃。  相似文献   
13.
A long-standing assumption in molecular biology posits that the conservation of protein and nucleic acid sequences emphasizes the functional significance of biomolecules. These conserved sequences fold into distinct secondary and tertiary structures, enable highly specific molecular interactions, and regulate complex yet organized molecular processes within living cells. However, recent evidence suggests that biomolecules can also function through primary sequence regions that lack conservation across species or gene families. These regions typically do not form rigid structures, and their inherent flexibility is critical for their functional roles. This review examines the emerging roles and molecular mechanisms of “nondomain biomolecules,” whose functions are not easily predicted due to the absence of conserved functional domains. We propose the hypothesis that both domain- and nondomain-type molecules work together to enable flexible and efficient molecular processes within the highly crowded intracellular environment.  相似文献   
14.
Adenohypophyses of human newborns contain characteristic psammoma bodies. Their numbers are maximal within 2 weeks of the neonatal period and diminish thereafter. They are very rare in infant pituitaries, seeming to disappear by shrinkage in that there is a significant direct correlation between their number and size. The bodies were found to contain a high concentration of endogenous peroxidase, thus suggesting that the enzyme may be responsible for their disappearance. A statistical majority of psammoma bodies were located within follicular lumens. By immunohistochemistry, the follicular epithelium surrounding psammoma bodies showed immunoreactivity for various pituitary hormones. Light microscopy demonstrated that adenohypophysial cells surrounding psammoma bodies contain randomly, scattered granules or globules exhibiting peroxidase activity. Extrusion of such granules into follicular lumens may play a role in the genesis of the concretions. The conspicuous lamellar nature of the calcified psammoma bodies suggests that waves of calcium deposition occur during their morphogenesis. Despite histologic similarities, the histochemical characteristics of this type of psammoma body differ from those in other organs as well as from the calcification encountered in prolactin (PRL)-producing pituitary adenomas.  相似文献   
15.
Summary An autopsy case of a Japanese male with familial -galactosidase and neuraminidase deficiency is reported. The clinical picture was characterized by adult onset, a gargoyle-like face, cerebellar ataxia, myoclonus, convulsions, retinal degeneration and cortical blindness.Histopathologically, most neurons seemed to have become degenerated in the whole cerebral cortex. Moreover, the calcarine cortex appeared spongy with depopulation of nerve cells. Stuffed neurons or neuronal storage changes were found throughout the brain, especially in the motor nuclei of the spinal cord and brain stem.The inclusions in the stuffed neurons revealed various profiles on the electron microscope. They were composed of membranous lamellar and/or multilamellar structures, often accompanying vacuoles and reminiscent of lipofuscin-like profiles.  相似文献   
16.
Corpora amylacea (C.A.) also named polyglucosan bodies (P.B.) are one of the hallmarks of normal brain aging. Although their functions are not yet clear, C.A. increase in number in patients suffering from neurodegenerative diseases. C.A. contain 88% of hexoses and 4% of proteins. Most of the proteins in C.A. are aging or stress proteins such as heat shock proteins, ubiquitinated proteins and advanced glycation end products which are also proinflammatory products. Stimulated by the potential role played by some S100 proteins in the inflammatory process which may be triggered in C.A., we investigated, by immunohistochemistry, the presence of different S100 proteins (S100A1, S100A2, S100A3, S100A4, S100A5, S100A6, S100A8, S100A9, S100A12 and S100B) in C.A. from normal human brain. Among the ten S100 proteins analyzed, nine (S100A) were detected in C.A. Three S100 proteins (S100A8, S100A9, S100A12) which are highly expressed in activated macrophages and used as inflammatory markers were detected in C.A. S100A8 was, in addition, found in thick neuronal processes from the pons. One (S100B) could not be found in C.A. although it was highly expressed in astrocytes. In C.A., the staining intensity was estimated by computer-assisted microscopy and gave the following order: S100A1 congruent withS100A8 congruent with S100A9>S100A5> or =S100A4>S100A12>S100A6> S100A2=S100A3. The potential inflammatory role played by S100 proteins in C.A. is discussed.  相似文献   
17.
目的:探讨后极部眼内异物取出方法。方法:借助眼用粘弹剂(玻璃酸钠)的粘弹性和内聚性,首先将异物包绕、游离、悬浮,然后视异物大小、形状酌情选用自制异物回吸针头或异物钳取出异物。结果:本组17例(17眼)后极部眼内异物,均一次顺利取出,无一发生手术误伤及手术并发症。术后视力提高14眼,不变2眼,下降1眼。结论:借助粘弹剂游离悬浮法取出后极部眼内异物,可显著降低手术难度、手术损伤及手术并发症。尤其是悬浮回吸异物,效果更优。  相似文献   
18.
孙刚  王竫华 《眼科新进展》2004,24(2):150-152
青光眼性损伤的形态学特征及病理机制 ,在视网膜节细胞水平及视神经水平已得到广泛研究 ;最近研究表明 ,青光眼对外侧膝状体、视皮质等中枢视路也存在相应损伤 ,并且提示青光眼的中枢损伤可能参与视功能状态的进一步恶化。我们对近年来青光眼中枢损伤的病理形态学及病理机制研究作一综述。  相似文献   
19.
目的探讨螺旋CT虚拟内诊镜(CTVE)在小儿气管、支气管异物诊断上的应用价值。 方法回顾性分析东南大学医学院附属徐州医院1998年1月至2004年12月收治的121例术前经CTVE诊断为气管支气管异物,并行支气管镜探查术患儿的诊疗情况,并分析CTVE诊断在临床应用上的意义及诊断的阳性符合率。 结果121例经CTVE诊断并行支气管镜探查证实并取除异物者115例,诊断符合率9504%。 结论CTVE检查是目前无创非侵入性诊断小儿气管支气管异物的较理想方法。  相似文献   
20.
Psammocarcinoma is a rare form of serous carcinoma of the ovary, associated with extensive psammoma body formation and invasion of surrounding structures. We report the case of a 63-year-old woman who presented with a highly calcified abdominopelvic mass and a raised CA-125 marker and who, following a full staging laparotomy, was diagnosed with stage IIIB ovarian psammocarcinoma. Serous ovarian psammocarcinoma is characterized by massive psammoma body formation, and despite the limited number of cases reported, it appears that the clinical prognosis is much more favorable than for the usual serous carcinomas and is similar to that of serous borderline lesions of the ovary. A summary of all the reported cases is provided to highlight the clinical and prognostic features of this rare tumor.  相似文献   
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