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41.
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   
42.
Maternally administered recombinant human granulocyte colony- stimulating factor (rhG-CSF) has been shown to cross the placenta and induce a peripheral neutrophilia and increases in the marrow and spleen neutrophil storage pools in fetal and newborn rats. In the present study, we have used this model system to investigate the efficacy of prenatally administered rhG-CSF on neonatal defense to a lethal challenge with Group B-beta hemolytic Streptococcus (GBS). Pregnant rats were injected with rhG-CSF twice daily beginning 6 days before parturition. At birth, all pups were infected with a dose of GBS that is lethal for 90% of infected pups (LD90). Survival was monitored daily for 5 days. Survival of infected pups from saline-treated mothers beyond 60 hours after infection was 10%. No difference in survival was observed among pups from mothers treated 2 and 4 days before parturition. In contrast, we determined that survival was 82.5% among infected pups from mothers treated for 6 days before parturition with rhG-CSF. Our results demonstrate that maternal administration of rhG- CSF augments neonatal defenses against a lethal bacterial challenge.  相似文献   
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The effects of granulocyte-macrophage colony-stimulating factor (GM- CSF) are not confined to cells of the myeloid lineage. GM-CSF has been shown to have effects on mature T cells and both mature and immature T- cell lines. We therefore examined the GM-CSF responsiveness of murine thymocytes to investigate whether GM-CSF also affected normal immature T lymphocytes. The studies presented here indicate that GM-CSF augments accessory cell (AC)-dependent T-cell receptor (TCR)-mediated proliferation of unseparated thymocyte populations. To identify the GM- CSF responsive cell type, thymic AC and T cells were examined for GM- CSF responsiveness. We found that GM-CSF augmentation of TCR-induced thymocyte proliferation appears to be mediated via augmentation of AC function, and not via direct effects on mature single-positive (SP) thymocytes. Enriched double-negative (DN) thymocytes were also tested for GM-CSF responsiveness. GM-CSF induced the proliferation of adult and fetal DN thymocytes in an AC-independent and TCR-independent single- cell assay. Thus, in contrast to the SP thymocytes, a DN thymocyte population was directly responsive to GM-CSF. GM-CSF therefore may play a direct role in the expansion of DN thymocytes and an indirect role in the expansion of SP thymocytes.  相似文献   
44.
Delay in hematologic recovery after bone marrow transplantation (BMT) can extend and amplify the risks of infection and hemorrhage, compromise patients' survival, and increase the duration and cost of hospitalization. Because current studies suggest that granulocyte- macrophage (GM) colony-stimulating factor (CSF) may potentiate the sensitivity of hematopoietic progenitor cells to G-CSF, we performed a prospective, randomized trial comparing GM-CSF (250 micrograms/m2/d x 14 days) versus sequential GM-CSF x 7 days followed by G-CSF (5 micrograms/kg/d x 7 days) as treatment for primary or secondary graft failure after BMT. Eligibility criteria included failure to achieve a white blood cell (WBC) count > or = 100/microL by day +21 or > or = 300/microL by day +28, no absolute neutrophil count (ANC) > or = 200/microL by day +28, or secondary sustained neutropenia after initial engraftment. Forty-seven patients were enrolled: 23 received GM-CSF (10 unrelated, 8 related allogeneic, and 5 autologous), and 24 received GM- CSF followed by G-CSF (12 unrelated, 7 related allogeneic, and 5 autologous). For patients receiving GM-CSF alone, neutrophil recovery (ANC > or = 500/microL) occurred between 2 and 61 days (median, 8 days) after therapy, while those receiving GM-CSF+G-CSF recovered at a similar rate of 1 to 36 days (median, 6 days; P = .39). Recovery to red blood cell (RBC) transfusion independence was slow, occurring 6 to 250 days (median, 35 days) after enrollment with no significant difference between the two treatment groups (GM-CSF: median, 30 days; GM-CSF+G- CSF; median, 42 days; P = .24). Similarly, platelet transfusion independence was delayed until 4 to 249 days (median, 32 days) after enrollment, with no difference between the two treatment groups (GM- CSF: median, 28 days; GM-CSF+G-CSF: median, 42 days; P = .38). Recovery times were not different between patients with unrelated donors and those with related donors or autologous transplant recipients. Survival at 100 days after enrollment was superior after treatment with GM-CSF alone. Only 1 of 23 patients treated with GM-CSF died versus 7 of 24 treated with GM-CSF+G-CSF who died 16 to 84 days (median, 38 days) after enrollment, yielding Kaplan-Meier 100-day survival estimates of 96% +/- 8% for GM-CSF versus 71% +/- 18% for GM-CSF+G-CSF (P = .026). These data suggest that sequential growth factor therapy with GM-CSF followed by G-CSF offers no advantage over GM-CSF alone in accelerating trilineage hematopoiesis or preventing lethal complications in patients with poor graft function after BMT.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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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   
49.
王继琛  王乐  李海  柯茂林 《医学争鸣》2005,26(14):1278-1278
1临床资料2003-06/2004—12收治髋部骨质疏松性骨折患20(男14,女6)例,年龄58—80(平均68.5)岁,股骨颈骨折13例,粗隆间骨折7例.对照组为老年性骨关节病或颈腰椎病患20例.均抽空腹静脉血4mL,3000r/min离心5min分离血清,4h内测定血清钙、磷,留血清-20℃保存备用,测定TGF-β1.用Au-2700全自动生化分析仪测定血清钙、磷,试剂由日本欧林巴斯公司提供.血清TGF-β1检测采用ELISA法,  相似文献   
50.
To estimate the incidence and causes of secondary thrombocytosis in children, a 12 month study of all patients attending a children's hospital and discovered to have a platelet count over two times the upper normal limit (> 800 x 10(9)/l) was undertaken. Data so obtained were analysed both separately and together with those from two previous studies to gain as broad a perspective as possible. Of 7916 children who had platelet counts during the study period, 36 (0.5%) produced a value > 800 x 10(9)/l; there were 19 boys and 17 girls. There was a preponderance of young infants (median age 13 months). Twenty seven of the 36 had some sort of associated infection, bacterial in 18 and viral in nine. The other nine were either recovering from anti-neoplastic chemotherapy (n = 6), were post-operative (n = 2), or simply iron deficient (n = 1). Combining these patients with those described in previous studies allowed a review of 139 unselected children with very high platelet counts. Fifty three (38%) had infections, 29 (20%) had traumatic or surgical tissue damage, 16 (11%) had malignant disease undergoing chemotherapy or surgery, and 13 (9%) had connective tissue or autoimmune disorders. Secondary thrombocytosis is not rare and is most frequently seen in very young infants after infection. It can arise in a wide variety of other circumstances including rebound from myelosuppression, iron lack, or as part of an acute phase response. It is clinically unimportant in terms of morbidity and requires no treatment other than that for the primary condition.  相似文献   
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