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151.
p53 is very often mutated in human cancers. The majority of alterations are missense mutations located within the DNA-binding domain of the protein. Many reports have characterized such mutant proteins. Little is known, however, about the properties of proteins that have a missense mutation outside this domain. We investigated here the properties of 8 mutant proteins identified in human tumors as having a missense mutation in the tetramerization domain. The Arg342Gln, Glu349Asp and Gln354Arg proteins behaved like wild-type both in vitro and in cells. Two mutants, Arg342Pro and Leu344Pro, were inactive in all assays. Finally, the 3 mutant proteins Leu330His, Arg337Cys and Arg337Leu, which are inactive in vitro, showed no activity at low expression levels in cells but became active at higher expression levels. Our results reveal new phenotypes for p53 mutants and suggest that sequencing of the p53 gene from patients with tumors should be extended to exons 9 and 10 in clinical investigations.  相似文献   
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The clinico-immunological examination of 57 patients with chronic bacterial prostatitis was carried out. The clinical analysis made it possible to divide the patients into 3 groups characterized by the presence of chronic inflammatory diseases of other organs which had appeared before (group 1) or after (group 2) the manifestation of the symptoms of prostatitis, aw well as by the absence of concomitant inflammatory diseases (group 3). At the same time these patients were found to have changes in their immune status, most pronounced in patients of groups 1 and 2. The clinico-immunological analysis of the patients with chronic bacterial prostatitis revealed the fact that chronic bacterial prostatitis was a chronic inflammatory process linked with changes in the immune system; these changes had the signs of secondary immunodeficiency and required immunocorrective therapy.  相似文献   
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The functional status of the oxidative-antioxidative system was studied in 72 patients after vast cancer operations. Traditional surgical treatment and its combination with intraoperative irradiation were shown to lead to tense antioxidative defense and to suppressed T-cell immunity and to call for antioxidative and immunomodulating therapy. High intraoperative blood loss complicated by hemorrhagic shock injured the oxidative-antioxidative system greatly. The magnitude of this damage correlated with the rate of prehypoxia. Addition of the potent antioxidant Ceruloplasmin to the drug regimen normalized a recovery period, helped to correct posthypoxic multiorgan insufficiency, to recover oxidative-antioxidative balance, and to decrease the incidence of pyoinflammatory complications. Patients with endogenous intoxication showed activated lipid peroxidation, decreased functional activity of antioxidative defense components and of T-cell immunity in homeostasis. The use of Ceruloplasmin and Laprot had pronounced antiinflammatory and detoxifying effects on the patient's body and activated its antioxidative defense.  相似文献   
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Methods of inhibiting the hyperacute antibody-mediated rejection that occurs when pig organs are transplanted into primates have been investigated using the baboon as a potential recipient. Baboons were treated with different regimens that included combinations of (1) splenectomy, (2) pharmacologic immunosuppression (CsA, cyclophosphamide, corticosteroids +/- methotrexate), and (3) intravenous infusion of oligosaccharides. The cytotoxicity of the serum was then assessed on cultures of pig kidney cells (PK15). Unmodified serum caused approximate 65-100% pig cell destruction. Splenectomy and/or pharmacologic immunosuppression, and infusions of dextran, dextrose or mannitol, did not result in any reduction of cytotoxicity. Infusions of melibiose and/or arabinogalactan, both of which have terminal non-reducing alpha-galactose, however, decreased relative PK15 cell damage significantly in a dose-dependent manner. At high concentrations (< or = 50 g/hr), complete inhibition of cytotoxicity was achieved in 4 of 15 baboons. The extracorporeal immunoadsorption of baboon serum utilizing immunoaffinity columns of melibiose also resulted in a significant reduction (of approximately 80%) in cytotoxic effect. In 1 baboon, melibiose and arabinogalactan infusion delayed vascular rejection of a pig cardiac xenograft from 10 min to about 12 hr, at which time the baboon died from the toxic effects of the carbohydrate infusion. These observations (1) add further support to the role that anti-alpha-galactosyl antibodies play in the hyperacute rejection of pig tissues transplanted into primates, and (2) demonstrate that serum cytotoxicity can be reduced by the intravenous infusion of alpha-galactosyl oligosaccharides or by extracorporeal immunoadsorption using these carbohydrates.  相似文献   
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AIM: The expression of CD95(Fas/APO-1) antigen was studied on bone marrow cells of 19 MDS patients, peripheral blood blast cells of 15 acute myeloid leukemia (AML) patients, blast cells and granulocytes of 68 patients with chronic myeloid leukemia (CML)--24 in chronic, 9 in accelerated phase and 35 in blastic crisis (BC)--by indirect surface immunofluorescence assay using flow cytometry (FACScan, Becton Dickinson, USA). RESULTS: CD95(Fas/APO-1) antigen was revealed on bone marrow cells of 8 out of 19 (36.8%) MDS patients; the percentage of antigen-positive cells was 38.1 +/- 19.2%; on 45.5 +/- 22.8% of cells in 6(45%) of 15 AML patients. Fas/APO-1 antigen was totally absent in CML chronic stage; its expression was found in 34% (12 of 35) of our patients with CML BC on peripheral blood blasts and in 56% (5 of 9) on peripheral blast cells of CML patients in acceleration phase. CONCLUSION: The data on overall survival of CD95-positive MDS patients suggest that the presence of Fas antigen is a favorable prognostic sign for patients with MDS. The patients from CD95-negative group represent a risk group both for survival and AML transformation. In CML BC group the survival does not depend upon Fas-antigen expression.  相似文献   
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