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排序方式: 共有327条查询结果,搜索用时 0 毫秒
1.
Jonathan S. Jahr Fedor Lurie Bernd Driessen Jessica A. Davis Robert Gosselin Robert A. Gunther 《Journal canadien d'anesthésie》2002,49(3):243-248
PURPOSE: Accuracy of measurement of low hemoglobin concentrations using the HemoCue, a B-hemoglobin photometer (HemoCue AB, Angelholm, Sweden) may exhibit significant variability. Infusion of hemoglobin-based oxygen carriers (HBOC) results in low concentrations of plasma hemoglobin. Our study assessed B-hemoglobin photometer measurement accuracy of three HBOC: (hemoglobin glutamer-200 (bovine; Oxyglobin, Biopure Corp., Cambridge, MA, USA); hemoglobin glutamer-250 (bovine; Hemopure, Biopure Corp, Cambridge, MA, USA), and hemoglobin-raffimer, (human; Hemolink, Hemosol, Inc., Toronto, Ontario, Canada). METHODS: In the laboratory, 45 split canine plasma samples were mixed with hemoglobin glutamer-200 (8.13, 16.25, 32.5 g x L(-1) concentrations), 45 samples were mixed with hemoglobin glutamer-250 (8.13, 16.25, 32.5 g x L(-1) concentrations), 45 with hemoglobin-raffimer (12.5, 25.0, 50.0 g x L(-1) concentrations), and measured. Plasma samples without HBOC served as control. Hemoglobin concentration was determined by a laboratory analyzer (Coulter Corporation, Hiafeah, FL, USA) and B-hemoglobin photometer (HemoCue, Angelholm, Sweden). Two independent technicians performed blinded sample measurements and randomly tested each sample five times. Results were analyzed according to Bland and Altman analysis. RESULTS: B-hemoglobin photometer demonstrated high repeatability for all three HBOCs. Repeatability coefficients were 0.37 g x L(-1) and 0.48 g x L(-1) for hemoglobin glutamer-200, 0.39 g x L(-1) and 0.4 g x L(-1) for hemoglobin glutamer-250 and 1.07 g x L(-1) and 0.85 g x L(-1) for hemoglobin-raffimer. An acceptable agreement was found between the B-hemoglobin photometer and the laboratory analyzer for all three HBOCs tested. CONCLUSION: The B-hemoglobin photometer accurately determined the concentration of three HBOC solutions dissolved in canine plasma. 相似文献
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Technical considerations in the surgical approach to multiple accessory pathways in the Wolff-Parkinson-White syndrome 总被引:1,自引:0,他引:1
J G Selle W C Sealy J J Gallagher J M Fedor R H Svenson S H Zimmern 《The Annals of thoracic surgery》1987,43(6):579-584
Surgical techniques for the approach to and division of atrioventricular accessory pathways have been designed and perfected during the past 18 years. The standard method of exposure of a single left free wall accessory pathway is by a left atriotomy. All other single accessory pathways are exposed through a right atriotomy. Up to twenty percent of patients with Wolff-Parkinson-White (WPW) syndrome harbor multiple atrioventricular accessory pathways. In this subgroup, classic operative techniques, especially the methods of approach, must be combined or modified depending on the specific locations of the accessory pathways encountered. Eighteen of 90 patients operated on for WPW syndrome at Charlotte Memorial Hospital from August, 1983, through September, 1986, had multiple accessory pathways. Thirty-eight of thirty-nine pathways were successfully divided. One posterior septal accessory pathway reappeared 2 months postoperatively and was catheter ablated. The most frequent combination of atrioventricular accessory pathways included a right free wall and a posterior septal accessory pathway (10 patients). This combination is approached by a right atriotomy. The posterior septal space dissection is extended onto the right free wall area. Technically the most difficult combination includes a left free wall and a posterior septal accessory pathway (3 patients in the present series). Our preferred approach is begun with a right atriotomy for the posterior septal space dissection, followed by an atrial septotomy to expose the left free wall area. There are other methods, however, that may be advantageous depending on the exact locations of the accessory pathways encountered. 相似文献
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Werner Schultz Fedor Mirisch 《Virchows Archiv : an international journal of pathology》1927,264(3):760-773
Ohne ZusammenfassungMit 16 Textabbildungen. 相似文献
5.
Fedor Kryuchkov Alison Robertson Elizabeth M. Mudge Christopher O. Miles Soetkien Van Gothem Silvio Uhlig 《Toxins》2022,14(6)
Ciguatera poisoning is a global health concern caused by the consumption of seafood containing ciguatoxins (CTXs). Detection of CTXs poses significant analytical challenges due to their low abundance even in highly toxic fish, the diverse and in-part unclarified structures of many CTX congeners, and the lack of reference standards. Selective detection of CTXs requires methods such as liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS) or high-resolution MS (LC–HRMS). While HRMS data can provide greatly improved resolution, it is typically less sensitive than targeted LC–MS/MS and does not reliably comply with the FDA guidance level of 0.1 µg/kg CTXs in fish tissue that was established for Caribbean CTX-1 (C-CTX-1). In this study, we provide a new chemical derivatization approach employing a fast and simple one-pot derivatization with Girard’s reagent T (GRT) that tags the C-56-ketone intermediate of the two equilibrating C-56 epimers of C-CTX-1 with a quaternary ammonium moiety. This derivatization improved the LC–MS/MS and LC–HRMS responses to C-CTX-1 by approximately 40- and 17-fold on average, respectively. These improvements in sensitivity to the GRT-derivative of C-CTX-1 are attributable to: the improved ionization efficiency caused by insertion of a quaternary ammonium ion; the absence of adduct-ions and water-loss peaks for the GRT derivative in the mass spectrometer, and; the prevention of on-column epimerization (at C-56 of C-CTX-1) by GRT derivatization, leading to much better chromatographic peak shapes. This C-CTX-1–GRT derivatization strategy mitigates many of the shortcomings of current LC–MS analyses for C-CTX-1 by improving instrument sensitivity, while at the same time adding selectivity due to the reactivity of GRT with ketones and aldehydes. 相似文献
6.
This study examined a comprehensive screening model within children attending Head Start programs from urban (n =232) and rural (n = 231) communities. The Devereux Early Childhood Assessment (DECA; LeBuffe & Naglieri, 1999 ) was used to measure social‐emotional protective factors (i.e., Total Protective Factors [TPF]) and risk factors (i.e., Behavior Concerns [BC]) within children that resided in two different community settings. Children from low‐income rural programs received higher scores on a subscale measuring children's relationship to adults (i.e., Attachment subscale). Additionally, children from low‐income urban programs received higher scores on children's ability to self‐regulate (i.e., Self‐Control subscale). Significant differences between children from rural and urban settings were not found on the primary scales (BC or TPF) of the DECA. Statistically significant gender differences by community‐type were not found. Findings contribute to the literature by illustrating that community characteristics might influence the development of different social‐emotional behaviors in preschool children. © 2011 Wiley Periodicals, Inc. 相似文献
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We hypothesized that decreasing elevated night‐time heart rate (HR) in hypertension by administering a bradycardic agent (ivabradine) at bedtime could bring cardiovascular benefit. Since rats are nocturnal animals, they exhibit circadian rhythms phase‐shifted relative to humans. Sixty‐six Wistar rats were divided into non‐diseased controls and rats with l ‐NAME‐induced hypertension to compare the haemodynamic effects of daytime‐dosed and night‐time‐dosed ivabradine. l ‐NAME‐induced hypertension inverted the physiological 5.6% night‐to‐day HR dip to an undesirable HR rise by 11.1%. Ivabradine dosed at daytime (the rat's resting phase) reverted a night‐to‐day HR rise to HR dip by 14.2%. These results suggest a cardiovascular benefit of ivabradine dosed at the human's resting phase (night‐time) for hypertensive patients with nondipping HR. 相似文献
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