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31.
SUMMARY. This study compared plateletpheresis on the Haemonetics PCS Plus (PCS Plus) and the Baxter Autopheresis C (Auto C) using the same 100 selected donors. The number of packs meeting UK BTS/NIBSC specification (>2.2 times 1011 platelets per pack) was achieved by 99% of PCS Plus and 82% of Auto C procedures. The positive correlation found between donor precount and final platelet yield was better for the PCS Plus. Both machines met U.K. specification for white-cell contamination but this was significantly greater for the Auto C. Plasma yields were similar.
As a result of this study we chose to use the PCS Plus for routine plateletpheresis in our unit. This has enabled us not only to comply with UK BTS/NIBSC specifications for apheresis platelets easily and cost effectively but also to meet our own higher specification (2.75 times 1011 platelets per pack) using existing staff and without extending the working day. 相似文献
As a result of this study we chose to use the PCS Plus for routine plateletpheresis in our unit. This has enabled us not only to comply with UK BTS/NIBSC specifications for apheresis platelets easily and cost effectively but also to meet our own higher specification (2.75 times 10
32.
目的:探讨心肌缺血患者外周血白细胞计数及活性与心肌缺血发生发展的相关性。方法:对74例心肌缺血患者进行回顾性统计,以白细胞计数lO×109/L分组,大于此数患者归于异常组,小于此数则属于正常组.把心肌缺血患者分为两组.一组为心肌梗死组,另一组为心绞痛组,以健康体检者为对照组,分别就患者组与健康对照组在ld~3d/4d~6d/7d—lOd/lld—14d分四个阶段进行白细胞计数及活性测定。结果:心肌梗死组的白细胞计数明显高于冠心病组及正常对照组;随着病情的减轻白细胞计数逐渐下降,其白细胞活性与其记数呈正相关;且心肌梗死组白细胞教异常的病例数明显高于冠心病组及正常对照组。结论:白细胞数及活性的升高参与了心肌缺血的病理生理过程。 相似文献
33.
Naoyuki Hashiguchi Yu Chen Christian Rusu David B. Hoyt Wolfgang G Junger 《European Journal of Trauma》2005,31(4):379-388
AbstractBackground and Purpose: Polymorphonuclear neutrophils (PMNs) protect the host from invading microorganisms, but excessive PMN activation after trauma causes tissue injury. Rapid monitoring of PMN function is critical for the assessment of the inflammatory state of trauma patients. Here, the authors adapted two simple and rapid methods to measure oxidative burst and degranulation of human PMNs in whole blood to avoid potential interference of cell isolation procedures with the assessment of PMN function.Material and Methods: Heparinized blood was drawn from healthy volunteers or trauma patients, preincubated at 37 °C for 5 min, and stimulated with N-formyl-methionyl-leucyl-phenylalanine (fMLP). Four assays for oxidative burst were tested: (1) cytochrome C; (2) homovanillic acid (HVA); (3) Amplex® Red; and (4) flow cytometry with dihydrorhodamine 123 (DHR). PMN degranulation was assessed with flow cytometry using antibodies to: (1) CD11b/Mac-1 (CD18); (2) CD63; and (3) CD66b (CD67).Results: With the exception of the DHR method, all methods to measure oxidative burst were found to be unsuitable in whole blood due to interference of plasma proteins and hemoglobin with the fluorimetric or photometric readouts. By contrast, all degranulation methods were suitable for whole-blood studies. However, for the assessment of formyl peptide-induced degranulation, anti-antibodies to CD11b/Mac-1 and CD66b were up to five times more sensitive than antibodies to CD63. Thus, the degranulation and DHR methods were optimized for increased sensitivity, speed, and specificity and their usefulness to measure PMN function in trauma patients was tested.Conclusion: The whole-blood methods based on flow cytometry with DHR, anti-CD11b/Mac-1, and anti- CD66b are rapid, simple, and reliable techniques to assess PMN function for trauma research. 相似文献
34.
GREEN M.S.; SHAHAM J.; GREEN J.; HARARI G.; BERNHEIM J. 《European journal of public health》1993,3(1):14-17
The increased risk of coronary heart disease in cigarette smokersmay be due at least partly to an elevation of the leucocytecount Chronic passive smoking has also been found to be associatedwith an increased risk of coronary heart disease, but its effecton the leucocyte count has not been reported. In this study250 male factory employees aged 2064 years were interviewedon smoking behaviour and exposure to environmental tobacco smoke,and blood counts were determined. Urinary cotinine was measureby radio-immunoassay and corrected for urinary creatinine concentrations.Mean leucocyte count was significantly higher among smokerscompared with non-smokers (8,666 compared to 6, 900; p<0.001).On the basis of smoking history, passive smokers had leucocytecounts similar to non-smokers. These findings were confirmedwhen leucocyte counts were compared with urine cotinine to creatinineratios. The association of haematocrlt and haemoglobin withsmoking was similar to that of leucocyte count These findingssuggest that any association of passive smoking with coronaryheart disease is not through an elevation of leucocyte count. 相似文献
35.
H. Klüter I. Dörges E. Maass T. Wagner H. Bartels H. Kirchner 《Annals of hematology》1996,73(2):85-89
Random-donor platelet concentrates (PC) prepared from pooled buffy coats have recently been described as an alternative method
for platelet preparation. We evaluated such PCs in the clinical setting compared with a standard PC from platelet apheresis.
PCs were prepared either from pools of buffy coats (BC-PC) or from single donors (SD-PC) with the cell separator CS-3000 plus.
PCs were stored for up to 5 days before transfusion. We compared fresh PC (day 1) with stored (day 2–3) and long-stored PC
(day 4–5). For analysis, platelet increment in the recipient was determined immediately and 16–22 h (mean 20 h) after transfusion,
corrected for total body area and transfused platelets (CCI). A total of 316 PCs were administered to 36 thrombocytopenic
patients suffering from various hematological disorders. Patients with detectable HLA or platelet-specific antibodies or splenomegaly
were excluded from the study. Mean platelet content of the PC was 262×109 for BC-PC and 251×109 for SD-PC. The 20-h CCI after transfusion of fresh PC was slightly higher with BC-PC than with SD-PC (14.5 versus 11.9;p=0.19), but values did not differ significantly between the two types of PC on any day of storage. For BC-PC, 20-h CCI decreased
with further storage by 30% (10.2;p=0.02). For SD-PC a decrease by 9% was not significant. In conclusion, platelet concentrates prepared from pools of buffy
coats showed excellent transfusion results when administered fresh, but storage decreased the CCI by 30%. No significant difference
from PCs from plateletpheresis was observed on any day of storage. Both types of platelet concentrates were capable of sufficient
platelet increment even when stored for up to 5 days.
Received: 28 December 1995 / Accepted: 14 May 1996 相似文献
36.
37.
The performance of the CELL-DYN 1700® (Abbott Diagnostics, Abbott Park, IL, USA) was evaluated in a tertiary care hospital laboratory using the guidelines proposed by the German Society of Clinical Chemistry. Precision, accuracy, linearity, background counts, and carry-over were satisfactory for all measured standard parameters including haemoglobin concentration, haematocrit, red blood cell count, mean corpuscular volume (MCV), red cell distribution width (RDW), white blood cell count and platelet count. With 259 selected normal and abnormal blood samples the results of the CELL-DYN 1700® (CD1700) compared very well (r > 0.96 for all parameters with exception of RDW) with those obtained with the Bayer Diagnostic H-1 and the Hoffmann-La Roche Cobas Argos systems. This study considered in particular the performance of the CD1700 three-part leucocyte differential. For those samples without instrument-generated suspect flags, the neutrophil and lymphocyte percentages were highly correlated with the results of the H-1 blood cell counter (r = 0.97 and 0.98, respectively) and with manual 400-cell differentials (r = 0.91 and 0.88, respectively). In contrast, the CD1700 mid-fraction which comprised the composite total of mono cytes, eosinophils, basophils and precursor white cells (when present) could not be directly compared to the differentials from the H-1 system or from manual microscopy. For those samples with CD1700 instrument suspect flags, the neutrophil and lymphocyte differential results also compared well with both the H-1 (r = 0.93 and 0.93, respectively) and manual estimates (r = 0.89 and 0.87, respectively). In conclusion, the CD1700 is an accurate haematology analyser for cellular blood counts and three-part leucocyte differentiation. 相似文献
38.
探讨中性粒细胞与淋巴细胞比值(NLR)对≥80岁急性缺血性脑卒中患者90 d预后的价值。方法 纳入2019年1月—2021年6月发病7 d内、≥80岁的缺血性卒中患者476例的相关信息、影像结果、随访结果,按照入组患者NLR的四分位数间距分为Q1组(NLR <2.97)、Q2组( 2.97≤NLR <4.49)、Q3组( 4.49≤NLR <7.94)、Q4组 (NLR≥7.94),每组119例。根据不良结局发生率绘制K-M曲线,比较各组在不同时期的生存概率。采用Cox多因素回归分析影响患者不良预后的因素。结果log-rank检验显示,四组患者的生存率存在差异,Q4组的90 d生存率显著低于Q1组(P<0.05)。多因素Cox回归分析显示,校正危险因素后,高NLR和高NIHSS评分是90 d死亡率的独立危险因素(P<0.05)。根据ROC曲线,高NLR预测患者90 d死亡曲线下面积为0.74。结论 高NLR为影响≥80岁高龄急性缺血性卒中患者90 d预后的独立危险因素,对高龄急性缺血性脑卒中患者的90 d预后有预测价值 相似文献
39.
40.
Secretion of a chemotactic factor for neutrophils and eosinophils by alveolar macrophages from asthmatic patients 总被引:10,自引:0,他引:10
Philippe Gosset Ph.C. AndrBernard Tonnel M.D. Michel Joseph Ph.D. Lionel Prin M.D. Anne Mallart M.D. Jacques Charon D.D.S. Andr Capron M.D. 《The Journal of allergy and clinical immunology》1984,74(6):827-834
The studies presented in this article demonstrate the release of an IgE-dependent chemotactic factor for polymorphonuclear neutrophils (PMN) and eosinophils by alveolar macrophages (AMs) from normal subjects (n = 15) and allergic asthmatic patients (n = 15). A 60-minute incubation of normal AMs previously sensitized by 20% nonheated allergic sera with anti-human IgE antibody or the related allergen induced the release of a chemotactic activity (CA) for PMN and eosinophils in culture supernatants. When AMs were obtained from asthmatic patients, direct incubation with anti-IgE or the related allergen induced the same CA, whereas incubation with an unrelated allergen failed to produce CA (neutrophil CA after addition of anti-IgE, 22.5 +/- 3.5 cells per high power field; with related allergen, 15.8 +/- 3.6; with unrelated allergen, 0.7 +/- 1.8; p less than 0.0001). A partial characterization of the neutrophil chemotactic factor was carried out. Enzymatic treatment by trypsin or carboxypeptidase or by heating (56 degrees C for 3 hr) failed to abolish the neutrophil CA. After gel filtration the greater part of the neutrophil CA (80%) was recovered among low-molecular-weight components (300 to 1300 daltons). A preliminary deactivation of PMN by leukotriene B4 suppressed the CA of AM supernatants. These results indicate that IgE-dependent stimulation of AMs produces a neutrophil and eosinophil CA, present in a low-molecular-weight fraction possibly related to leukotrienes, and emphasizes the role of AMs in inflammatory lung processes during allergic asthma. 相似文献