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991.
BA Hyma ; SB Moore ; JP Grande ; JJ Talmo ; RK Reisner ; J Rakela ; RA Krom 《Transfusion》1988,28(3):276-279
Immune hemolytic anemia in patients after organ transplantation has been reported generally to be graft-cell-derived due to elaboration by the donor's "passenger" lymphocytes of the antibodies directed against the recipient's red cell antigens. In contrast, this report presents a case that illustrates postoperative red cell alloantibody production by the recipient of an orthotopic liver transplant. Anti-Jka, -c, and -S, detected in the recipient's serum 9 days after transplantation, resulted in significant hemolysis. These alloantibodies had not been present in the recipient's serum before transplantation or in the sera of the liver or blood donors. In addition, anti-Jka and -c were eluted from posttransfusion red cells. The patient was transfused during surgery with crossmatch-compatible blood, that carried the alloantigens Jka, c, and S. The liver donor's red cells also carried the Jka, c, and S antigens. The recipient's pretransplantation red cell phenotyping was Jk(a-), c-, S-. The recipient had received only one transfusion 10 years prior to this operation, after which time he was noted to have anti-K. Immunosuppression initially consisted of cyclosporine, azathioprine, and prednisolone. This is believed to be the first report of delayed immune hemolysis due to non-ABO antibodies in a liver transplant patient treated with cyclosporine. 相似文献
992.
Mood states in the volunteer blood donor 总被引:2,自引:0,他引:2
Mood changes across time were evaluated as they applied to the process of volunteer blood donation. Measures of mood (from the Mood Adjective Check List) were taken before and at three different intervals after blood donations by 245 college students. Anxiety scores were significantly higher before blood donation, and elation scores showed a significant increase following donation. Veteran donors experienced significantly less discomfort before donation. These findings imply that blood donations can be viewed as an "opponent-affective process," in which initial, mildly aversive feelings lead to positive aftereffects. Current findings suggest that blood donation can be explained, in part, by a self-serving, addictive process. 相似文献
993.
994.
ML-236B is a competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase, the key regulatory enzyme in the sequence that catalyzes the conversion of acetate to mevalonic acid in cholesterol biosynthesis. This compound caused marked inhibition of human bone marrow granulocyte progenitor cell (CFU-C) proliferation, the 50% inhibitory concentration (IHD50) being 2.0 X 10(6)M. Inhibition of colony formation was reversed by mevalonic acid but not by cholesterol. ML-236B also inhibited DNA synthesis and acetate incorporation into cholesterol in marrow mononuclear cells (IHD50 = 5.6 x 10(6)M and 3.2 x 10(7)M, respectively). No inhibition of mevalonate incorporation into cholesterol was observed. These results differ from those observed with 25-hydroxycholesterol, another inhibitor of HMG CoA reductase. The latter compound also inhibited CFU-C proliferation and cholesterol biosynthesis from acetate; inhibition of colony formation was reversed by cholesterol but not by mevalonic acid. In addition, 25- hydroxycholesterol inhibited cholesterol synthesis from mevalonic acid precursor. We conclude that: (1) ML-236B is a potent inhibitor of CFU-C proliferation, DNA synthesis, and cholesterol biosynthesis from acetate precursor in marrow mononuclear cells; (2) the effects of ML-236B are completely reversed by mevalonic acid but not by cholesterol, suggesting that mevalonic acid per se or one or more of its nonsterol products are critical for cell growth; (3) the inhibitory effects of 25- hydroxycholesterol on CFU-C proliferation and cholesterol biosynthesis are not solely a result of its inhibition of HMG CoA reductase, but are due in part to inhibition of enzymatic steps distal to mevalonic acid in the sterol synthetic pathway; and (4) mevalonic acid and cholesterol are independent requirements for CFU-C proliferation and differentiation in vitro. 相似文献
995.
The plasma cell labeling index (PCLI) and serum beta 2-microglobulin (beta 2M) are independent prognostic factors in multiple myeloma (MM). Recently, levels of thymidine kinase (TK) and C-reactive protein (CRP) have been shown to have prognostic value. We studied 107 patients with newly diagnosed myeloma to determine whether TK and CRP values added prognostic information not already available using the PCLI and beta 2M. Univariate survival analysis showed prognostic significance for the PCLI, TK, beta 2M, age, serum albumin, and CRP. Multivariate analysis showed that only PCLI and beta 2M have independent prognostic significance. The survival curves were better separated using the PCLI and beta 2M than with other combinations of variables. Among nine patients under age 65 with low PCLI and low beta 2M, eight were alive almost 6 years after starting chemotherapy. These good-risk patients could not be identified by standard clinical features. Although creatinine and calcium were normal, other features such as bone lesions, osteoporosis, fracture, and anemia were present and stage distribution was similar to other patients in the study. In conclusion, PCLI and beta 2M measured at diagnosis are independent prognostic factors. They must be considered when interpreting the results of clinical trials and should be helpful in counseling patients and in designing new trials. When the PCLI and beta 2M values are known, the TK and CRP values do not add useful additional prognostic information. 相似文献
996.
997.
Restorative materials containing antimicrobial agents: is there evidence for their antimicrobial and anticaries effects? A systematic review 下载免费PDF全文
The aim of this systematic literature review was to investigate whether the incorporation of antimicrobial agents into dental restorative materials truly exerts an antimicrobial effect against common cariogenic bacteria (primary outcome), and whether the inclusion of antimicrobial agents is able to prevent caries around restorations (secondary outcome). MEDLINE, via PubMed, was searched for papers published between 1980 and 30 November 2014. A total of 1126 articles were retrieved. After inclusion/exclusion assessment, 147 full text articles were read and included in the review, comprising 130 in vitro, 1 in situ, and 4 in vivo studies, as well as 12 literature reviews. In about 78% of in vitro studies, and in all identified in situ and in vivo studies, a positive antimicrobial effect had been found. However, the anticaries effect had not been tested in any of the selected studies. It was concluded that there is indeed evidence that restorative dental materials containing antimicrobial agents exert an antimicrobial effect, both in laboratory and in clinical studies. However, no evidence has been found regarding the role of these agents in preventing or controlling dental caries, or in preventing caries around restorations. 相似文献
998.
Application of molecular genetics to prenatal diagnosis and carrier detection in the hemophilias: some limitations 总被引:2,自引:0,他引:2
Prenatal diagnosis and carrier detection in the hemophilias have received much attention in recent years. The error rate in prenatal diagnosis by fetoscopy is less than 1%; fetoscopy is not possible, however, until the second trimester of pregnancy. Carrier detection based on bioassays of plasma has an irreducible error rate (approximately 5%?), because of the "lyonization" phenomenon in heterozygous women, and the final results are always probabilistic. New DNA methods promise to alleviate these difficulties. Prenatal diagnosis can be accomplished in the first trimester. "Lyonization" is bypassed in carrier detection, and the results may sometimes be essentially nonprobabilistic. But the DNA methods have certain limitations of their own which are not widely appreciated. Aside from cost and the necessity to adopt a new technology, there are inherent genetic problems: mothers must be heterozygous for both a disease gene and a marker gene, final results are probabilistic if the marker gene lies outside the disease gene, and multiple marker genes are often in linkage disequilibrium. We have concluded that a clinical unit planning to use the DNA methods must also maintain the conventional methods at a high level of performance. 相似文献
999.
Selective expression of the common acute lymphoblastic leukemia (gp 100) antigen on immature lymphoid cells and their malignant counterparts 总被引:16,自引:2,他引:16
The selectivity of monoclonal antibody J-5 (anti-gp 100, common ALL antigen) for normal and leukemic hemopoietic cells has been investigated. J-5 gave concordant reactions with rabbit anti-cALL, coredistributed on the cell surface, and precipitated a similar if not identical glycoprotein from leukemic and normal tissue. Normal, immature lymphoid cells reactive with J-5 were detected in bone marrow and in fetal thymus. In marrow they were largely coincident with the TdT+ population. J-5 defines a major subgroup of ALL (common ALL) with a favorable prognosis. Of 853 non-ALL acute leukemias investigated, 80 were J-5 positive. These included 14 cases diagnosed as AML, 51 TdT+ blast crises of CGL, and 15 cases diagnosed as "AUL." Of the 14 J-5+ AML, 13 were subsequently rediagnosed either as cALL (10 cases) or mixed lymphoid-myeloid leukemias (3 cases). One-hundred forty-three cases of mature lymphoid cell leukemia (91 B, 52 T) were investigated with J-5; 3 cases only, of disseminated B lymphoma, were positive, albeit weakly. A higher proportion of follicular lymphomas are, however, J-5 positive when studied in sections of biopsy material. A similar pattern of selective reactivity was observed in a series of leukemia/lymphoma cell lines. These studies emphasize the diagnostic value of monoclonal anti-cALL reagents. 相似文献
1000.
t(3;21)(q26;q22): a recurring chromosomal abnormality in therapy- related myelodysplastic syndrome and acute myeloid leukemia 总被引:6,自引:3,他引:6
Rubin CM; Larson RA; Anastasi J; Winter JN; Thangavelu M; Vardiman JW; Rowley JD; Le Beau MM 《Blood》1990,76(12):2594-2598
We have identified an identical reciprocal translocation between the long arms of chromosomes 3 and 21 with breakpoints at bands 3q26 and 21q22, [t(3;21)(q26;q22)], in the malignant cells from five adult patients with therapy-related myelodysplastic syndrome (t-MDS) or acute myeloid leukemia (t-AML). Primary diagnoses were Hodgkin's disease in two patients and ovarian carcinoma, breast cancer, and polycythemia vera in one patient each. Patients had been treated with chemotherapy including an alkylating agent for their primary disease 1 to 18 years before the development of t-MDS or t-AML. We have not observed the t(3;21) in over 1,500 patients with a myelodysplastic syndrome or acute myeloid leukemia arising de novo or in over 1,000 patients with lymphoid malignancies. We have previously reported that the t(3;21) occurs in Philadelphia chromosome-positive chronic myelogenous leukemia (CML). Thus, the t(3;21) appears to be limited to t-MDS/t-AML and CML, both of which represent malignant disorders of an early hematopoietic precursor cell. These results provide a new focus for the study of therapy-related leukemia at the molecular level. 相似文献