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91.
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A deficiency of adenosine deaminase, an enzyme important in purine nucleoside catabolism, is associated with a severe combined immunodeficiency disease in children. Inhibition of this enzyme in vitro and in vivo results in an impairment in lymphoblast proliferation. We have investigated the pharmacologic inhibition of this enzyme by 2'-deoxycoformycin in 15 patients with hematologic malignancies. Biochemical consequences of the administration of this agent were closely monitored in erythrocytes, nucleated peripheral blood and bone marrow cells, serum, and urine. A marked rise in erythrocyte dATP was accompanied by a depletion of ATP in those patients exhibiting toxicity. Most patients excreted large amounts of deoxyadenosine but not adenosine in the urine. Serum deoxyadenosine rose in patients demonstrating a marked decrease in cell mass. The biochemical disturbances and clinical toxicity, including hepatic, renal, and conjunctival abnormalities, were usually reversible. Central nervous system toxicity, which potentially was the most serious consequence, was associated with high erythrocyte dATP/ATP ratios and high levels of cerebrospinal fluid deoxyadenosine. In patients with lymphoma and leukemia, objective responses were observed but were short- lived. Patients with chronic lymphocytic leukemia receiving weekly low doses of the drug demonstrated minimal toxicity and some efficacy. The chemotherapeutic potential o 2'-deoxycoformycin, as either a single agent or in combination with Ara-A, merits further exploration.  相似文献   
93.
The aim of this study was to review the life of Mary E. O'Sullivan and to summarize her important contributions to the study of migraine. Mary E. O'Sullivan underwent extensive training to become a neurologist at a time when only 5% of women in America were physicians. She published five papers on migraine. In a 1936 Journal of the American Medical Association article, she described a patient with ergotamine overuse headache and recommended that daily doses of oral ergotamine should be avoided. Three years later she described migraine as a 'complex' syndrome with multiple causes and multiple cures. Mary E. O'Sullivan, an ambitious female headache specialist of the 1930s, was an early advocate of the use of ergotamine to treat migraine, yet she was one of the first to report ergotamine overuse headache. Although her life was short, her research, knowledge and ambition at a time when women had limited opportunities in medicine have left a mark.  相似文献   
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Kristensen  JS; Ellegaard  J; Hokland  P 《Blood》1987,70(4):1063-1068
We have developed a simple two-color immunofluorescence assay equally suited for microscopy and flow cytometry detecting hairy cells (HCs) in single cell suspensions, based on the concomitant reactivities with the B cell-specific monoclonal antibody B1 (CD20) and the monocyte/HC- associated antibody SHCL-3 (CD11c). Thus, HCs can be demonstrated in peripheral blood, bone marrow, and spleen specimens from hairy cell leukemia (HCL) patients even when they constitute less than 1% of the cell suspension. Likewise, admixture experiments with normal mononuclear cells and the MOLT-4 T-acute lymphocytic leukemia (ALL) cell line demonstrated that HCs could be detected in amounts as low as 1%. The validity of this assay has been ascertained by the lack of double marker positivity in cell suspensions from B-chronic lymphocytic leukemia (CLL) and acute myelogenous leukemia (AML) patients that only expressed B1 or SHCL-3, respectively. Furthermore, other malignant blood diseases, including malignant lymphomas, acute leukemias, and chronic leukemias disclosed no double marker positive cells. In a clinical setting, this assay was used for purifying HCs (by flow cytometry) from the peripheral blood from patients with no apparent morphological evidence of circulating HC infiltration and for monitoring the effect of interferon therapy. In conclusion, this assay should be of value for both diagnosis and monitoring patients with HCL.  相似文献   
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Smythe  JS; Spring  FA; Gardner  B; Parsons  SF; Judson  PA; Anstee  DJ 《Blood》1995,85(10):2929-2936
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes.  相似文献   
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Abramson  JS; Hudnor  HR 《Blood》1994,83(7):1929-1934
Patients infected with influenza A virus (IAV) are at increased risk for bacterial superinfections, and this occurs in association with depressed polymorphonuclear leukocyte (PMNL) function. Recently, we reported that in vitro exposure of human PMNL to granulocyte-macrophage colony-stimulating factor (GM-CSF) reverses IAV-induced cell dysfunction. The present study used an established animal model of IAV infection to examine whether G-CSF and/or GM-CSF can overcome IAV- induced PMNL dysfunction and thereby prevent secondary infections. Preliminary studies determined a dosing schedule of these cytokines that caused significant priming of chinchilla PMNL. In subsequent studies, animals were inoculated intranasally with IAV (day 1) followed 3 days later by Streptococcus pneumoniae, and administered daily intraperitoneal injections with a cytokine or placebo on days 3 through 9. Animals had blood obtained on multiple occasions for PMNL studies, and were followed-up for evidence of pneumococcal disease. Both cytokines caused significant priming of the PMNL chemiluminescence response and this was associated with reversal of the IAV-induced PMNL dysfunction. However, neither cytokine decreased the incidence of pneumococcal disease.  相似文献   
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