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Target-controlled infusion of alfentanil for postoperative analgesia: a feasibility study and pharmacodynamic evaluation in the early postoperative period 总被引:10,自引:0,他引:10
Van Den Nieuwenhuyzen MCO.; Engbers FHM.; Burm AGL.; Vletter A. A.; Van Kleef J. W.; Bovill J. G. 《British journal of anaesthesia》1997,78(1):17-23
We have examined the feasibility of target-controlled infusion of
alfentanil (TCIA) and the pharmacodynamics of alfentanil in the early
postoperative period. Patients were allocated randomly to one of the three
groups to receive balanced anaesthesia with bolus injections of fentanyl
(group F), sufentanil (group S) or alfentanil (group A). In the recovery
room all patients received the same analgesic regimen, comprising TCIA. To
evaluate the efficacy of postoperative analgesia, pain scores were measured
on a visual analogue scale (VAS) and patients indicated a need for
additional analgesia. EC50, the concentration at which, with a 50%
probability, patients reported adequate analgesia, was estimated using
logistic regression. Six patients did not complain of pain. The time from
the last intraoperative bolus injection of opioid until patients complained
of postoperative pain was shorter (P < 0.05) in group A (mean 68 min)
than in group F (101 min) and group S (136 min). The time to onset of
satisfactory analgesia was comparable in the three groups (median 18 min in
group F, 15 min in group S and 14 min in group A). EC50 of alfentanil was
determined in 28 patients; mean values were 26 ng ml-1 (group F), 39 ng
ml-1 (group S) and 52 ng ml-1 (group A). We conclude that TCIA, under the
conditions studied, resulted in a fast onset of adequate analgesia,
irrespective of the opioid administered during operation. Also, there was
no effect of opioids administered during operation on postoperative
pharmacodynamics of alfentanil.
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Factor VIII assays. Assessment of variables 总被引:1,自引:0,他引:1
J T Brandt D A Triplett K Musgrave C Arkin E G Bovill F V Lucas W A Rock 《Archives of pathology & laboratory medicine》1988,112(1):7-12
Factor VIII assays are the most common specific coagulation factor assay performed in the United States. Interlaboratory proficiency studies have documented persistent problems with variation in results between laboratories. The Coagulation Resource Committee of the College of American Pathologists conducted a workshop to analyze variables that may affect performance of the one-stage factor assay. The results indicate that accuracy of the assay can be improved by uniform standardization of reference plasma samples and that reproducibility can be enhanced through appropriate choice of reagents and instruments. Optimizing performance of this assay should lead to more reproducible interlaboratory results. 相似文献
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Normal and diseased isolated lungs: high-resolution CT 总被引:8,自引:0,他引:8
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The adhesion of hematopoietic progenitor cells to bone marrow stromal cells is critical to hematopoiesis and involves multiple effector molecules. Stromal cell molecules that participate in this interaction were sought by analyzing the detergent-soluble membrane proteins of GBI/6 stromal cells that could be adsorbed by intact FDCP-1 progenitor cells. A single-chain protein from GBI/6 cells having an apparent molecular weight of 37 Kd was selectively adsorbed by FDCP-1 cells. This protein, designated p37, could be surface-radiolabeled and thus appeared to be exposed on the cell membrane. An apparently identical 37- Kd protein was expressed by three stromal cell lines, by Swiss 3T3 fibroblastic cells, and by FDCP-1 and FDCP-2 progenitor cells. p37 was selectively adsorbed from membrane lysates by a variety of murine hematopoietic cells, including erythrocytes, but not by human erythrocytes. Binding of p37 to cells was calcium-dependent, and was not affected by inhibitors of the hematopoietic homing receptor or the cell-binding or heparin-binding functions of fibronectin. It is proposed that p37 may be a novel adhesive molecule expressed on the surface of a variety of hematopoietic cells that could participate in both homotypic and heterotypic interactions of stromal and progenitor cells. 相似文献
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