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61.
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Since its recalibration in 1987, the Reflotron "dry-chemistry" cholesterol method can produce accurate results. Here we report how cholesterol concentrations in venous blood, plasma, and serum determined with Reflotron compare with values determined for fingerstick samples. When no EDTA is used in the latter, accurate results may meet the WHO/CDC criterion of a maximum bias less than or equal to 5%. Reflotron users should avoid use of EDTA. Lot-to-lot variation among the solid-phase reagent carriers was evaluated in four lots of these strips. The largest difference, 0.4 mmol/L, was seen in a commercial quality-control serum with a cholesterol concentration of approximately 7 mmol/L. The maximum differences in results for several serum pools were not always found between the same reagent lots, although the highest results in five of six materials occurred with a single lot of strips. As in all clinical chemical testing, regular quality control is necessary.  相似文献   
63.
Between June 1989 and June 1992, 144 patients participated in sequential clinical trials using peripheral blood progenitor cells (PBC) as their sole source of hematopoietic rescue following high-dose chemotherapy. All patients had received prior extensive combination chemotherapy and had marrow defects that precluded autologous bone marrow transplantation (ABMT). PBC were collected according to a single apheresis protocol. The initial 86 patients (group 1) had PBC collected without mobilization. Beginning in April 1991, PBC were mobilized solely with recombinant human granulocyte-macrophage colony-stimulating factor (rHuGM-CSF). Thirty-four patients (group 2) received rHuGM-CSF at a dose of 125 micrograms/m2/d by continuous intravenous infusion, and 24 patients (group 3) received rHuGM-CSF at a dose of 250 micrograms/m2/d by continuous intravenous infusion. Patients underwent at least six aphereses and had a minimum of 6.5 x 10(8) mononuclear cells (MNC)/kg collected. Cytokines were not routinely administered immediately after transplantation. A median of nine aphereses were required to collect PBC in group 1 and seven aphereses for groups 2 and 3 (P = .03). The time required to recover 0.5 x 10(9)/L granulocytes after transplant was significantly shorter (P = .0004) for the mobilized groups; the median time to recovery was 26 days for group 1, 23 days for group 2, and 18 days for group 3. Transplantation of PBC mobilized with rHuGM-CSF resulted in a shorter time to platelet (P = .04) and red blood cell (P = .01) transfusion independence. Mobilization with rHuGM-CSF alone resulted in efficient collection of PBC, that provided rapid and sustained restoration of hematopoietic function following high-dose chemotherapy. Mobilization of PBC with rHuGM-CSF alone is an effective method for patients who have received prior chemotherapy and have bone marrow abnormalities.  相似文献   
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Cytogenetic studies of 68 patients who developed secondary leukemia (SL)/dysmyelopoietic syndrome (DMS) after extensive chemotherapy and/or radiation therapy as well as patients who developed SL/DMS without such treatment showed that those patients who received radiation alone or with chemotherapy had more extensive numerical and structural abnormalities than those who received only chemotherapy. In terms of the specific chromosomal abnormalities, there are no differences between the various treatment groups. Hypodiploidy is the most common form of aneuploidy in these patients, with the most common numerical abnormality being the loss of chromosome 7. The most common structural abnormalities involved chromosomes 3 and 5. When compared with patients with de novo leukemia and DMS, the chromosomal abnormalities in these patients are more complex and extensive. Serial studies revealed that cytogenetic abnormalities do not precede the development of hematologic changes by significant time periods.  相似文献   
68.
Jaffe  HS; Cadman  EC; Farber  LR; Bertino  JR 《Blood》1986,68(2):562-564
Pretreatment hematocrit in 117 advanced-stage Hodgkin's disease patients treated with a combined modality therapy program was evaluated as an independent prognostic variable with regard to survival and relapse-free survival. Age greater than 40 years, and multiple extranodal sites of involvement were found to be statistically significant independent negative prognostic factors with regard to survival. Pretreatment hematocrit, however, was not an independent negative prognostic variable.  相似文献   
69.
Burgess  AW; Nicola  NA; Johnson  GR; Nice  EC 《Blood》1982,60(5):1219-1223
A microculture assay for murine granulocyte-macrophage colony- stimulating factor (GM-CSF) has been developed using fetal liver GM colony-forming cells (CFC) isolated by fluorescence-activated cell sorting. These GM-CFC are free of mature hemopoietic cells, such as granulocytes and macrophages, which may interfere with direct assays for GM-CSF. The assay procedure allows the quantitation of GM-CSF within 48 hr by measuring the number of cells produced from 50 GM-CFC in microcultures (15 microliter). The assay is particularly simple to set up and score and yet, because of the reduced volumes, this assay is still capable of detecting 0.2 pg (i.e., 0.2 U) of GM-CSF within 48 hr, i.e., 100 times less GM-CSF than the conventional soft agar assay. By allowing the microcultures to develop for 7 days, the extra proliferation allows a further tenfold increase in the sensitivity of CSF detection. The time and cost of setting up hundreds of GM-CSF assays for fractions from chromatographic columns, e.g., reverse phase high performance liquid chromatography, is reduced by at least five- fold. Enough GM-CFC can be isolated and stored frozen in one afternoon to provide sufficient cells for the daily assay of 200 samples of GM- CSF for several months. Microassay results for several sources of GM- CSF at different stages of purification are compared to the results obtained from the soft agar assay.  相似文献   
70.
We assessed the prevalence and predictors of latent Toxoplasma infection in a large group of human immunodeficiency virus (HIV)-infected and HIV-uninfected at-risk US women. The prevalence of latent Toxoplasma infection was 15% (380 of 2525 persons) and did not differ by HIV infection status. HIV-infected women aged > or =50 years and those born outside of the United States were more likely to have latent Toxoplasma infection, with prevalences of 32% and 41%, respectively.  相似文献   
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