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BACKGROUND:SIRPalphal is well known as a negative regulator for cell proliferation through the regulation of the activity of receptor tyrosine kinase with ITAM motif. No investigation to data was undertaken on SIRPalphal involving liver regeneration. MATERIALS AND METHODS: Adult male Sprague-Dawley rats underwent approximately 700% partial hepatectomy (PH) or sham operation (SO). Liver specimens were collected at 2,6,12,24,30,48,72,120,168,and 240 h after PH or SO.  相似文献   
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BACKGROUND: Surgery is the first treatment of a pigmented skin lesion when a melanoma is suspected. This excision is most of the time realized by the dermatologist as well as the second time surgery. Bleeding at the surgical site may have numerous aetiologies. Fibrinolysis is a rare but dramatic event. CASE REPORT: We report a case with delayed bleeding after excision of a melanoma. The patient was re-operated and a major haemorrhage followed so that a transfusion of blood and fresh frozen plasma was necessary. The biological investigations concluded to a subacute primitive fibrinolysis associated with the melanoma. The patient was first considered to have completely recovered when a blood-borne liver metastasis diffusion rapidly occurred. The patient deceased within a few months from a hepatic encephalopathy with hepatic metastases. DISCUSSION: We find only a few published cases of melanoma with fibrinolysis. Its association with other abnormalities, like a partial factor XIII deficiency, made these abnormalities even more difficult to identify. The relation between the subacute fibrinolysis, the melanoma and the liver infiltrative metastasis is difficult to establish.  相似文献   
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Factors such as developmental stage or physiological and infectious stress may change patterns of post-translational protein modification. In order to determine whether such regulated types of modification may influence T cell responsiveness to self proteins we examined the T cell response of SJL (H-2s) mice to alphaB-crystallin, a small heat shock protein that can exist in differentially phosphorylated forms. Epitope mapping revealed the presence of two T cell epitopes that are presented by I-As. One major epitope including residues 41-56 contains an amino acid residue (Ser45) that can be phosphorylated as the result of aging or stress. Accordingly, T cells from SJL mice discriminate between preparations of alphaB-crystallin that differ in their extent of phosphorylation at the level of whole protein as well as at the level of determinant-specific responses. Phosphorylation at Ser45 does not prevent binding of the peptide 41-56 to I-As and computer-assisted modelling of the peptide-MHC complex suggests that the phosphate group of the bound peptide extends outwards from the peptide-binding cleft and may thus be available for direct contact with TCR. Together, our data provide evidence that stress-inducible phosphorylation of alphaB- crystallin creates neo-determinants for T cells and, therefore, may contribute to the breakdown of peripheral tolerance to this self protein.   相似文献   
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CD4+/CD56+ hematodermic neoplasm, formerly known as blastic NK cell lymphoma, is an aggressive and rare preculsor hematologic neoplasm recently recognized by the WHO-EORTC classification consensus for cutaneous lymphomas. The neoplasm tends to affect elderly patients, who usually present with skin lesions but often have a disseminated disease, including bone marrow involvement. Although the lesions are composed of cells with a lymphoblast-like morphology and an NK-cell phenotype, exhibiting a CD4+, CD56+ positive immunophenotype, recent studies support a relationship to plasmacytoid dendritic cells. Because of the rarity of this disease, we describe two patients suffering a CD4+/CD56+ hematodermic neoplasm.  相似文献   
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