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Prevertebral sympathetic ganglia develop markedly enlarged argyrophilic neurites as a function of age, gender and diabetes. Immunolocalization studies demonstrate their preferential labeling with antisera to highly phosphorylated 200 kDa neurofilament (NF-H) epitopes, NPY, peripherin and synapsin I, but not to hypophosphorylated NF-M and NF-H or MAP-2. The immunophenotype of dystrophic neurites in conjunction with the results of histochemical and ultrastructural studies are consistent with the terminal axonal and/or synaptic origin of neuritic dystrophy in the sympathetic ganglia of aged and diabetic human subjects. 相似文献
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AV Maximychev IG Kostyuchenko FKh Chibirova EA Zhilinskaya LN Chekulaeva SF Timashev 《Canadian Metallurgical Quarterly》1997,10(5):487-501
Purple membranes (PM) from Halobacterium were reconstituted with 57Fe ions and investigated by M?ssbauer spectroscopy within the temperature range from 5 to 300 K at the Fe/bacteriorhodopsin (BR) ratio 0.6-300. When the Fe/Br ratio was below 2, Fe3+ bonded to PM mostly as hydroxymonomeric particle [FeOH]2+.5H2O, the apparent charge of the iron ion being two. When the Fe/BR ratio exceeded two, the dimeric form [FeOH](2+)4.8H2O along with a cluster form dominated. The temperature dependences of the mean square displacement show that the mobility of Fe ions changes from the solid-state type to the quasi-diffusional one at temperatures approximately 200 and approximately 230 K for the dimeric or monomeric and cluster iron forms, respectively. The nature of the cation binding sites and their location on the PM surface are discussed. A possible role of the divalent cation binding to PM in the mechanism of BR proton pumping is suggested. 相似文献
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AS Saribekian VA Ponomarev AI Ishmukhametov LN Poliakova 《Canadian Metallurgical Quarterly》1998,98(8):23-26
The paper presents the results of both conservative and surgical treatment of 300 patients with hypertension, complicated by intracranial hematoma. It is shown that the results of therapy depend on the size and location of hematoma, on the severity of both perifocal disorders and dysfunction of truncal structures as well as on the dynamics of arterial pressure and degree of somatic burden. 相似文献
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MF Philips J Dormans D Drummond L Schut LN Sutton 《Canadian Metallurgical Quarterly》1997,26(3):130-143
For over 60 years congenital kyphotic deformities of the spine have been categorized into two distinct groups, depending on the developmental defect. Those arising from a failure of formation of the vertebral bodies were classified as type 1, while those arising from a failure of segmentation were referred to as type 2. Recognition of the progressive and unstable nature of the type 1 defects alerted physicians to the need for early operative stabilization through decompression and stabilization through instrumentation. As the embryogenesis of the spinal column was further investigated, and as diagnostic imaging methods of the spine improved, unstable congenital kyphoses were further subdivided. Progressive congenital kyphotic deformities now may accompany a host of vertebral column developmental defects as well as genetically mediated mesenchymal tissue defect syndromes. This paper presents 5 patients from The Children's Hospital of Philadelphia with progressive and symptomatic congenital kyphotic deformities of the spine. Two of these lesions resulted from defects of formation of the vertebral bodies, while one resulted from segmental spinal dysgenesis, maldevelopment of both the anterior and posterior vertebral elements. One patient's kyphotic deformity was a result of caudal regression syndrome, and the final case presented experienced a high thoracic kyphosis from a syndrome associated diffuse midline mesenchymal tissue abnormalities known as cerebrocostomandibular syndrome. All patients showed evidence of progressive cord compression and required neural element decompression, fusion, and instrumentation. The cases are discussed individually, and the developmental and clinical aspects of each are explored. 相似文献