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Osteomalacia and bone disease arising from aluminum   总被引:2,自引:0,他引:2  
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Two examples of localized primary amyloid tumor of the breast are presented, including one patient with metachronous bilateral lesions. Our findings and review of the literature indicate that this rare lesion occurs predominantly in elderly females and can be mammographically and clinically confused with carcinoma. Fine-needle aspiration biopsy can be a useful procedure to make a preliminary diagnosis. Congo red staining with prior potassium permanganate incubation confirmed the AL type of amyloid in our two cases; this might be the predominant type in the localized form involving the breast. Immunofluorescence studies demonstrated IgA, with kappa and lambda light-chain deposition within the amyloid foci in one case, and intracytoplasmic IgG with both light chains within plasma cells and amyloid deposits of the second case. Ultrastructural examination of one of the cases showed characteristic findings of straight, nonbranching fibrils of 4-9 nm, diagnostic of amyloid. From our findings and a review of the literature, we conclude that amyloid tumors of the breast can occur in three separate settings: secondary amyloidosis, systemic or multiple myeloma associated amyloidosis, and as a localized primary type having a benign course.  相似文献   
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FLP 62064 [N-(4-methoxyphenyl)-1-phenyl-1H-pyrazole-3-amine] is a dual inhibitor of prostaglandin synthetase and 5-lipoxygenase. The compound had anti-inflammatory activity in vivo in a number of models. It inhibited peritoneal inflammation induced by immune-complex when given locally. When applied to the skin, FPL 62064 inhibited UV irradiation-induced erythema and PGE2 formation in the guinea pig and also oedema formation and eicosanoid production in the mouse ear produced by arachidonic acid. Co-injected with arachidonic acid in rabbit skin, FPL 62064 inhibited oedema and eicosanoid formation.  相似文献   
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Expression of tau protein in non-neuronal cells can result in a redistribution of the microtubule cytoskeleton into thick bundles of tau-containing microtubules (Lewis et al.: Nature 342:498-505, 1989; Kanai et al.: J Cell Biol 109:1173-1184, 1989). We reconstituted microtubule bundles using purified tubulin and tau in order to study the assembly of these structures. Taxol-stabilized tubulin polymers were incubated with various concentrations of recombinant human tau and examined by electron microscopy. With increasing concentrations of tau 3 (tau isoform containing three microtubule binding domains) or tau 4 (isoform containing four microtubule binding domains) the microtubules changed orientation from a random distribution to loosely and tightly packed parallel arrays and then to thick cables. In contrast, tau 4L, the tau isoform containing four microtubule binding domains plus a 58-amino acid insert near the N-terminus, showed minimal bundling activity. tau 4-induced bundling could be inhibited by the addition of 0.5 M NaCl or 0.4 mM estramustine phosphate, conditions which are known to inhibit tau binding to microtubules. A tau construct that contained only the microtubule binding domains plus 19 amino acids to the C-terminus was fully capable of bundling microtubules. Phosphorylation of tau 3 with cAMP-dependent protein kinase had no effect on its ability to induce microtubule bundling. These results indicate that tau protein is directly capable of bundling microtubules in vitro, and suggests that different tau isoforms differ in their ability to bundle microtubule filaments.  相似文献   
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A close association has been recognized between activated T cells and eosinophils in asthma, albeit circumstantial. The present study attempted to investigate this relationship in an animal model of lung eosinophilia using the new generation of T cell-selective immunosuppressants, cyclosporin A and FK506, compared with the myelotoxic immunosuppressive agent cyclophosphamide. Antigen challenge of ovalbumin-sensitized guinea-pigs resulted in a lung eosinophilia which was assessed by bronchoalveolar lavage. All three agents caused a marked suppression of lung eosinophilia at 24 h post-challenge when the compounds were administered at the time of sensitization but not when administered for 3 days before lavage. However, the lung eosinophilia at 72 h post-challenge was reduced significantly by FK506 and by cyclophosphamide, but not by cyclosporin A, when the drugs were administered for 3 days, before lavage. These results strongly suggest the involvement of T cells in antigen-induced late phase (72 h) eosinophilia in guinea-pigs but not at 24 h. The effects of cyclophosphamide were always associated with a reduction in circulating white cell counts, whereas cyclosporin A and FK506 showed no myelotoxic properties. These results suggest the potential therapeutic use of selective, non-cytotoxic immunosuppressive agents in asthma.  相似文献   
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We describe 3 patients with ureteral calculi who failed multiple extracorporeal shock wave lithotripsy treatments and whose stones could not be visualized by ureteroscopy despite radiological confirmation. We contend that these ureteral stones migrated submucosally and are refractory to the aforementioned treatment modalities. Each patient had a common presenting complaint of intermittent flank pain 5 years in duration, leading us to believe that long-standing stone impaction is a prerequisite for this entity. Our experience is reviewed.  相似文献   
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Thirty six patients were admitted to hospital as a result of Salmonella virchow infection during an outbreak of food poisoning in Essex in 1984. Out of 12 patients with evidence of bloodstream invasion, one third presented primarily with meningism and attention is drawn to this unusual clinical picture.  相似文献   
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