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991.
992.
An optimized additive solution was developed for the postthaw preservation of red cells that contained adenine, glucose, disodium phosphate, and citrate buffer. This solution, called AS-17, was compared to AS-3 solution in a clinical trial using 40 subjects (20 in each arm). Fresh-frozen red cells were thawed and deglycerolized after 1 to 18 months and subjected to a second period of storage in either solution for up to 3 weeks at refrigerator temperatures. Both solutions yielded red cells with 24-hour survivals in excess of 75 percent. Cells stored in AS-3 for 21 days had a mean survival of 77 +/− 8 percent and cells stored in AS-17 a mean survival of 79 +/− 11 percent. The AS-17 solution resulted in improved maintenance of pH, p50, and 2,3 DPG compared to that with AS-3, but both solutions appear adequate for 3 weeks of postthaw storage.  相似文献   
993.
The results of this study provide compelling evidence for the existence of the gene or genes controlling optimal T-B-cell cooperative interactions in the designated I region of the H-2 gene complex. Previously, we have speculated that the relevant gene(s) involved may well be located in this region based on several observations from our earlier work in this area (3, 5, 6). Thus, in the preceding paper, we showed that T and B cells from B10.BR and A strain mice developed effective cooperative interactions in vitro to DNP-KLH in a system identical to the one reported herein. Since these mice differ for genes in the S and D regions of H-2 but are identical for K and I region genes, we were able to localize the critical genes to the K-end of H-2.  相似文献   
994.
Paroxysmal nocturnal hemoglobinuria (PNH) is an uncommon, acquired clonal stem cell disorder primarily affecting red cells that have an abnormal sensitivity to complement lysis. Since 1948, the use of saline-washed red cells (WRBCs) has been advocated to minimize hemolysis after transfusion to patients with PNH. Thirty-eight years of experience (1950 through 1987) with patients who had PNH were reviewed. Twenty-three patients with a positive Ham's test had been transfused with 556 blood components, including 431 RBC products: 94 units of whole blood, 208 units of packed RBCs, 80 units of white cell-poor RBCs, 38 units of WRBCs, 5 units of frozen RBCs, and 6 units of intraoperatively salvaged RBCs. Only one documented episode of posttransfusion hemolysis related to the underlying diagnosis of PNH was found, and it was associated with the transfusion of a unit of type O whole blood to an AB-positive individual. This unit contained ABO-incompatible plasma; this case was similar to one in an earlier report from which originated the recommendation for using WRBCs. The posttransfusion increment in hemoglobin concentration in patients receiving ABO-identical packed RBCs was comparable to that in patients receiving frozen or washed RBCs. These findings indicate that the use of WRBCs is unnecessary and that patients with PNH should be transfused with group-specific blood and blood products.  相似文献   
995.
Posttransfusion purpura: the therapeutic value of PlA1-negative platelets   总被引:1,自引:0,他引:1  
A case of PlA1-associated posttransfusion purpura (PTP) is reported, in which a previously sensitized patient developed life-threatening thrombocytopenia, purpura, hematuria, and bronchial bleeding. The patient was transfused with PlA1-negative single-donor apheresis platelets (from four different donors) on four occasions. The first transfusion resulted in a 1-hour posttransfusion increment of 57 x 10(9) per L. The use of two additional PlA1-negative apheresis platelets provided support for a tracheostomy. Bronchial bleeding leading to respiratory arrest was controlled with a fourth transfusion. All PlA1-negative platelet transfusions resulted in transient increases in the patient's platelet count. This is the first reported case of repeated, transiently effective transfusion of PlA1-negative platelets demonstrated during the acute phase of thrombocytopenia.  相似文献   
996.
Background: A relation between febrile reactions to platelet transfusion and high cytokine levels in platelet concentrates (PCs) was found previously. The levels of cytokines such as interleukin (IL)-6 are related to the while cell content of the PC during storage. Therefore, early removal of white cells should prevent reactions. Study Design and Methods: This prospective study was set up to compare methods for the preparation of random PCs, the platelet-rich plasma method (PRP-PCs), which results in a high white cell content, and the buffy coat method (BC-PCs), which results in a low white cell content, with regard to the frequency and severity of reactions to platelet transfusion and the IL-6 level of the PC. IL-6 was chosen because it is the major mediator of the acute-phase response. White cells were reduced in all PCs before transfusion. Results: Platelet transfusions (n = 584) in 64 patients were studied. An overall reaction frequency of 7.2 percent was observed. Transfusion reactions were seen predominantly in patients who received PRP-PCs (PRP-PCs: 9.3% vs. BC-PCs: 2.7%, p = 0.007). Allergic reactions were limited to transfusions of PRP-PCs. The following PRP-PC characteristics were significantly correlated with febrile transfusion reactions: IL-6 level (p < 0.0001), initial white cell count (p = 0.001), and storage time (p = 0.02). In this group, reactions were less frequent in patients receiving pretransfusion medication (p < 0.001). In the PRP-PC group, IL-6 content (p = 0.01) and initial white cell count (p = 0.04) were also significantly correlated with allergic reactions, which indicated that these or associated factors might have an effect on the outcome of this type of reaction. Conclusion: Febrile reactions are highly correlated with IL-6 levels in PCs. The low white cell content of BC-PCs is associated with undetectable IL-6 levels and a reduced frequency of febrile as well as allergic reactions in recipients. The BC method is the preferable one for the production of random-donor PCs.  相似文献   
997.
BACKGROUND: Peripheral blood progenitor cell (PBPC) components are being collected from healthy donors for allogeneic transplantation, but the quantity, quality, composition, and variability of PBPCs collected from healthy people given granulocyte-colony-stimulating factor (G-CSF) have not been evaluated. STUDY DESIGN AND METHODS: PBPC components were collected from 150 healthy people who were given G-CSF (5, 7.5, or 10 microg/kg/day) for 5 days. The components were evaluated for white cell (WBC), mononuclear cell, CD34+ cell, neutrophil, platelet, and red cell (RBC) composition. RESULTS: The quantities collected were: WBCs, 35.0 +/? 16.4 × 10(9) (range, 11.9–163.3 × 10(9)); mononuclear cells, 33.3 +/? 14.4 × 10(9) (range, 11.9–139.6 × 10(9)); CD34+ cells, 412 +/? 287 × 10(6) (range, 70–1658 × 10(6)); neutrophils, 1.71 +/? 3.59 × 10(9) (range, 0–27.6 × 10(9)); RBCs, 7.2 +/? 4.0 mL (range, 0–22.1 mL); and platelets, 480 +/? 110 × 10(9) (range, 250–920 × 10(9)). PBPC components collected from people given G-CSF at 7.5 or 10 microg per kg per day contained significantly more CD34+ cells (respectively, 428 +/? 300 × 10(6); range, 70–1658 × 10(6) and 452 +/? 294 × 10(6); range, 78- 1380 × 10(6)) than those from people given G-CSF at 5 microg per kg per day (276 +/? 186 × 10(6); range, 91–767 × 10(6)) (p = 0.007 and p = 0.002). When 10 microg per kg per day of G-CSF was given, 50 percent of the components contained enough CD34+ cells for transplantation to a 75- kg recipient (375 × 10(6) CD34+ cells), but 10.6 percent of the components contained less than 150 × 10(6) CD34+ cells and thus would provide a transplantable dose only for a 30-kg patient. CONCLUSION: One PBPC component collected from a healthy donor given 7.5 or 10 microg per kg per day of G-CSF should contain 70 to 1660 × 10(6) CD34+ cells, with 0 to 22 mL of RBCs. Because of the great variability in the number of CD34+ cells collected, the quantity of CD34+ cells in each component should be measured after each procedure to ensure that sufficient quantities of cells are present for a successful transplant.  相似文献   
998.
Miller  ME; Boxer  LA; Kawaoka  EJ; Border  WA 《Blood》1981,57(1):22-24
Cell elastimetry has been applied to the measurement of antineutrophil antibodies. This technique measures, under direct visualization, the negative pressure required of aspirate PMNs into small-pored pipettes. Two groups of studies were carried out: (A) In the first group of studies, normal PMNs were incubated with 1 of 8 known antineutrophil serums. Each serum significantly decreased membrane deformability-- i.e., cells became more rigid. The study was conducted in an entirely blind fashion. Randomly coded serums from patients and controls were studied for deformability by observers unaware of the code. (B) In the second group of studies, sera containing immune complexes were incubated with normal PMNs. No significant effects were noted upon deformability. As a single cell assay that partially reflects membrane rigidity, elastimetry may, therefore, have potential in the further characterization of mechanisms by which such antineutrophil antibodies compromise neutrophil functions.  相似文献   
999.
Abstract This study was conducted to describe level of conflict, conflict management styles, level of job satisfaction, and intent to stay, and to ascertain relationships among conflict, conflict management styles, level of job satisfaction, intent to stay, and turnover of professional nurses in Thailand. The sample was 354 professional nurses employed in four regional hospitals in Thailand. The findings showed that the overall level of conflict was at a moderate level. The majority of subjects used accommodation most frequently to manage conflict. Subjects were dissatisfied with pay but were neither satisfied nor dissatisfied with work, supervision, opportunities for promotion, co-workers and the job in general facets of job satisfaction. Most subjects had a high intent to stay in their present jobs for 1 year (97.1%) but intent to stay for the next 5 years decreased (78.5%). The result showed some relationships among these variables, but no relationship between intent to stay and turnover of professional nurses.  相似文献   
1000.
The predictors of red cell transfusions in total hip arthroplasties   总被引:8,自引:0,他引:8  
BACKGROUND: Most blood crossmatched in a hospital blood bank is for surgical patients, and the majority is never transfused. The maximal standard blood order schedule is used to promote efficient ordering practices for surgical patients. STUDY DESIGN and METHODS: To ascertain the predictors of red cell transfusions for patients undergoing total hip arthroplasty, the charts of 299 adult patients undergoing primary and revision total hip arthroplasty were reviewed. A surgical blood order equation was developed for calculating the number of units of red cells that should be ordered. Stepwise regression analysis was used to determine which patient-and-case-related variables should be considered in the surgical blood order equation. RESULTS: The significant indicators for allogeneic red cell transfusion to patients on the day of total hip arthroplasty were preoperative hemoglobin concentration, weight, age, estimated blood loss, and aspirin use. The surgical blood order equation would result in a lower crossmatch-to-transfusion ratio than would the maximal standard blood order schedule (1.23 vs. 3.14). Costs were also lower with the surgical blood order equation. CONCLUSION: Incorporation of patient factors resulted in increased efficiency of blood-ordering practices in total hip arthroplasty.  相似文献   
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