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Granulomatous slack skin is an indolent T-cell lymphoma, considered to be a variant of mycosis fungoides. Clinically it is characterized by areas of redundant skin, wrinkled, inelastic, with variable erythema and infiltration besides a poikilodermic surface. A differential diagnosis unknown to most dermatologists is the giant cell tumor of soft tissue, which is an extremely rare low-grade sarcoma. The authors report a patient who had undergone extensive surgery because of a primary diagnosis of giant cell tumor of soft tissue, but which proved to be granulomatous slack skin after a second interventional procedure with confirmatory histopathology.  相似文献   
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A 34-years-old floor-layer developed optic neuropathy and motor neuron disease after being accidentally exposed to a solvent mixture containing methanol and other substances. Optic neuropathy is a complication of methanol poisoning, but the onset of a motor neuron disorder resembling amyotrophic lateral sclerosis after the exposure to these substances has not been previously described. The temporal onset of the clinical symptoms, biological plausibility, young age of the patient and absence of neurological disorders in the family history raises suspicion of a possible causative relationship.  相似文献   
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Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents. CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive) were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma therapy affected the sensitivity of both histological and CSF-PCR methods. Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996  相似文献   
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Summary The virological findings obtained during an outbreak of Bornholm disease which took place in the summer 1957 in Cermignano, in the province of Teramo, Italy, are described. During this study it was possible to isolate 15 strains of a Goxsackie B2 type virus. 3 strains were isolated simultaneously from rectal and pharyn geal swabs, while 9 strains were isolated from pharyngeal swabs only.  相似文献   
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The localization of alpha-naphthyl acid esterase (ANAE) activity in T lymphocytes with receptors for IgM (TM cells) have been studied at the electron microscope. The electron-opaque product of the cytochemical reaction was detected around, but never inside, single (or groups of) vesicles, which suggested a possible membrane localization of the enzyme activity. These same vesicles were found to contain acid phosphatase by both light- and electron-microscopic examination and were bound by unit membranes; this data indicates that they likely represent primary lysosomes. The presence of such lysosomes in a restricted paranuclear area is a distinctive feature of TM cells.  相似文献   
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We have previously demonstrated the loss of oral tolerance (OT) in lymphotoxinalpha-/- (LTalpha-/-) and TNFalpha / lymphotoxinalpha deficient (TNFalpha / LTalpha-/-) mice which have defective Peyer's patches (PP) and lymph node (LN) development. We have now studied OT in BALB / c mice with differential defects of the gut-associated lymphoid tissue (GALT) caused by inhibition of LTbetaR signaling during fetal development. Treatment of pregnant mice with LTbetaR-IgG (LTbetaRIgG) and TNFR I55-IgG (TNFR55IgG) abrogates the formation of PP (LTbetaRIgG) or of PP and mesenteric LN (MLN) (LTbetaRIgG / TNFRIgG) without genetically deleting the respective cytokine pathways. OT was readily induced in mice without PP but retaining MLN (PP null / LN +). In contrast, OTcould not be induced in mice lacking both MLN and PP (PP null / MLN null) as shown by the inability of these mice to suppress IFN-gamma secretion or DTH reactions. We next assessed OT in 129 x B6 LTalpha-/- mice with and without MLN. Timed treatment of pregnant LTalpha-/- mice with an agonist anti-LTbetaR mAb induces formation of MLN but not of PP in LTalpha-/- mice. LN + LTalpha-/- mice developed OT while LN LTalpha-/- mice were resistant to OT induction. Taken collectively, the data show that in the presence of MLN PP are not required for OT induction and that the presence of MLN is sufficient for OT induction in the LTalpha-/- model.  相似文献   
10.
Emphysema is characterized by enlargement of the distal airspaces in the lungs due to destruction of alveolar walls. Alveolar endothelial and epithelial cell apoptosis induced by cigarette smoke is thought to be a possible mechanism for this cell loss. In contrast, our studies show that cigarette smoke condensate (CSC) induces necrosis in alveolar epithelial cells and human umbilical vein endothelial cells. Furthermore, study of the cell death pathway in a model system using Jurkat cells revealed that in addition to inducing necrosis, CSC inhibited apoptosis induced by staurosporine or Fas ligation, with both effects prevented by the antioxidants glutathione and dithiothreitol. Time course experiments revealed that CSC inhibited an early step in the caspase cascade, whereby caspase-3 was not activated. Moreover, cell-free reconstitution of the apoptosome in cytoplasmic extracts from CSC-treated cells, by addition of cytochrome-c and dATP, did not result in activation of caspases-3 or -9. Thus, smoke treatment may alter the levels of pro- and antiapoptogenic factors downstream of the mitochondria to inhibit active apoptosome formation. Therefore, unlike previous studies, cell death in response to cigarette smoke by necrosis and not apoptosis may be responsible for the loss of alveolar walls and inflammation observed in emphysema.  相似文献   
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