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Untreated and previously treated patients with paracoccidioidomycosis were studied for: (i) serum levels of total IgG, IgM and IgA immunoglobulins, by radial immunodiffusion and Paracoccidioides brasiliensis (Pb) antibodies, by indirect immunofluorescence; (ii) correlation between their levels with the clinical forms of the disease; (iii) correlation between the serum titres obtained by tube precipitin with those of anti-Pb IgG, IgM and IgA.In the untreated group, serum IgG levels were significantly increased in patients with the more systemic forms of the disease, especially the acute progressive form. Serum IgA levels were significantly increased in all patients with no statistical difference between clinical forms. Serum IgM levels were normal in all patients. Anti-Pb IgG, IgA and IgM were detected in 97·5%, 32·5% and 45·0% of all cases, respectively. There was a sharp tendency towards higher levels of anti-Pb IgG among those with the acute progressive form (83·4%) in relation to the chronic, more localized forms, mixed form (68·0%) and isolated organic form (55·5%). In the untreated and previously treated group sera, there was positive correlation between the level of anti-Pb IgG and positivity for the tube precipitin test, suggesting that the precipitin-type antibodies are of the IgG class.Broadly, the present data demonstrate a polyclonal activation of the humoral immune system in paracoccidioidomycosis, with a positive relationship between serological results and severity of the disease.  相似文献   
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The presence and localisation of T and B lymphocytes in biopsy specimens of human conjunctiva and lacrimal gland from 34 patients were studied in frozen sections. Eighteen patients had follicular conjunctivitis, 13 patients had Sjögren's syndrome, and 3 were normal. All cases of follicular conjunctivitis showed a similar picture. B cells were in higher number than T cells, but both types of lymphocytes were present in the infiltrates. In the developed follicles T cells occupied the periphery and B cells the central part of the infiltrates. In patients with Sjögren's syndrome the conjunctival biopsies showed a higher number of B lymphocytes. The number of T cells was higher in the lesions from Sjögren's syndrome than in cases of follicular conjunctivitis. The infiltrate in lacrimal gland biopsies showed T cells which were scattered while B cells were more numerous and formed clusters close to vessels. Normal conjunctiva and lacrimal gland showed no adherence of either sheep erythrocytes or human erythrocytes sensitised with antibody and complement.  相似文献   
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The central biochemical pathology of anorexia and the natural aging of the brain is similar. Biochemical models for drug withdrawal and depression may also assist in understanding geriatric anorexia. Norepinephrine, corticotropin releasing factor and beta-endorphin may key neurotransmitters in all of these conditions.  相似文献   
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