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61.
RP Juniper 《Canadian Metallurgical Quarterly》1998,185(2):94-97
Anemia associated with ACE inhibitors is rare but it may cause problems especially in patients with renal disease. This study assessed the acute effect of trandolapril, an ACE inhibitor, on serum erythropoietin (EPO) levels in uremic and hypertensive patients. Trandolapril 2 mg/day was given orally for three days and blood samples were collected on the first and third day. Trandolapril led to a significant decrease in serum EPO in patients with chronic renal failure. Although the drug lowered serum EPO in hypertensive patients, this effect was not statistically significant. This drop in serum EPO levels may be one of the mechanisms by which ACE inhibitors cause anemia, or worsen anemia, in uremic patients and further studies are needed to clarify this point. 相似文献
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63.
KJ Barakat K Cheng WW Chan BS Butler TM Jacks KD Schleim DF Hora GJ Hickey RG Smith AA Patchett RP Nargund 《Canadian Metallurgical Quarterly》1998,8(11):1431-1436
A new class of potent, orally active phenyl piperazine-based GH secretagogues have been discovered from attempts to mimic the arrangement of the phenyl substituent in the spiroindanyl piperidine and spiroindoline sulfonamide privileged structures of 4 and 1, respectively. The best of these compounds, 18 (EC50 = 2.8 nM) is nearly as potent as MK-0677 for releasing GH from rat pituitary cells. 相似文献
64.
MJ Soltis HJ Yeh KA Cole N Whittaker RP Wersto EC Kohn 《Canadian Metallurgical Quarterly》1996,24(7):799-806
BACKGROUND: Bronchoscopic bronchoalveolar lavage in children to investigate bronchial disorders such as asthma has both ethical and procedural difficulties. OBJECTIVE: The aim of this study was to establish a standardized non-bronchoscopic method to perform bronchoalveolar lavage in children attending for elective surgery to obtain normal cellular data. METHODS: Bronchoalveolar lavage was performed on normal children (n = 55) by infusing saline (20 mL) through an 8 FG suction catheter passed after endotracheal intubation. Oxygen saturation, heart and respiratory rate were monitored during the bronchoalveolar lavage procedure. Cellular analysis and total protein estimation of the lavage fluid were performed. Epithelial lining fluid volume was calculated (n = 15) using the urea dilution method. RESULTS: The procedure was well tolerated by all children. Total cell count and differential cell count for children (macrophages 70.8 +/- 2.3%, lymphocytes 3.8 +/- 0.6%, neutrophils 5.7 +/- 1.0%, eosinophils 0.14 +/- 0.03%, epithelial cells 19.6 +/- 2.1%, mast cells 0.21 +/- 0.02%) were similar to those reported for adults. Age and sex comparisons revealed no differences between groups. The mean total protein recovered in the cell free supernatant was 49.72 +/- 4.29 mg/L and epithelial lining fluid volume was 0.82 +/- 0.11% of return lavageate. CONCLUSION: This method allows bronchoalveolar lavage to be performed safely and quickly on children attending for routine elective surgery. Using this method and taking the 'window of opportunity' of elective surgery, the presence or absence of airway inflammation could be studied in children with various patterns of asthma during relatively asymptomatic periods. 相似文献
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66.
The oxidation behavior in air at 973 K of theaustenitic stainless steels 18Cr8Ni and17Cr-2.5Ni-10.5Mn-2Cu-0.17N (low-nickel content), wasstudied in a thermobalance. The steels were heated fromroom temperature up to 973K at 10 K min-1, oxidizedfor 80 hr and then cooled to room temperature at 80 Kmin-1. The two steels had the same weightgains, 0.18 mg cm-2, which is equivalent tooxidation layers about 1.15 m theoretical thickness. In both cases, thegeneral shapes of the WS-1 (mgcm-2) curves vs. t (hours) were parabolic,but X-ray diffraction of the oxidized surfaces, surfaceand crosssection optical microscopy and SEM observations and EDSmicroanalysis show important differences betweenthem. 相似文献
67.
The solubility parameter of poly(ethylene oxide) at 25°C has been determined using the method developed by DiPaola-Baranyi and Guillet, by the extrapolation of the values of the interaction parameter χ, at high temperatures, ranging from 70°–90°, 90°–110° and 110°–130°C down to 25°C. The values of the solubility parameter obtained, depending on the temperature ranges employed, are 9.8, 9.9 and 10.1, respectively. 相似文献
68.
A. Zecchina F. Geobaldo C. Lamberti S. Bordiga G. Turnes Palomino C. Otero Areán 《Catalysis Letters》1996,42(1-2):25-33
Fourier transform IR spectroscopy of CO and N2, adsorbed at liquid nitrogen temperature, was used to characterize an MFI-type H-FeZSM-5 ferrisilicate which was synthesized with a Si/Fe ratio of 50. Thermal treatment of this material at 773 and 973 K was performed in order to follow formation of extraframework species. On samples fired at 773 K Brønsted acid sites were present which gave an O-H stretching band at 3630 cm–1. These hydroxyl groups formed adducts with both probe molecules, which were monitored by the corresponding bathochromic shift, . Corresponding values for adsorbed CO and N2 were = –270 and = – 100, respectively. Increasing the firing temperature up to 973 K led to complete removal of iron from the zeolite framework, and consequent disappearance of Brønsted acidity. In this process, extraframework iron oxide species were formed which were also characterized by IR spectroscopy of the adsorbed probe molecules. Both CO and N2 gave Lewis-type adducts with coordinatively unsaturated Fe3+ ions present in the extraframework material. A comparison is made with results of a previous study on the H-GaZSM-5 isomorph. 相似文献
69.
Factor Graph Modeling of Rigid‐body Dynamics for Localization,Mapping, and Parameter Estimation of a Spinning Object in Space
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This paper presents a new approach for solving the simultaneous localization and mapping problem for inspecting an unknown and uncooperative object that is spinning about an arbitrary axis in space. This approach probabilistically models the six degree‐of‐freedom rigid‐body dynamics in a factor graph formulation. Using the incremental smoothing and mapping system, this method estimates a feature‐based map of the target object, as well as this object's position, orientation, linear velocity, angular velocity, center of mass, principal axes, and ratios of inertia. This solves an important problem for spacecraft proximity operations. Additionally, it provides a generic framework for incorporating rigid‐body dynamics that may be applied to a number of other terrestrial‐based applications. To evaluate this approach, the Synchronized Position Hold Engage Reorient Experimental Satellites (SPHERES) were used as a testbed within the microgravity environment of the International Space Station. The SPHERES satellites, using body‐mounted stereo cameras, captured a dataset of a target object that was spinning at ten rotations per minute about its unstable, intermediate axis. This dataset was used to experimentally evaluate the approach described in this paper, and it showed that it was able to estimate a geometric map and the position, orientation, linear and angular velocities, center of mass, and ratios of inertia of the target object. 相似文献
70.
ET Crosby RM Cooper MJ Douglas DJ Doyle OR Hung P Labrecque H Muir MF Murphy RP Preston DK Rose L Roy 《Canadian Metallurgical Quarterly》1998,45(8):757-776
PURPOSE: To review the current literature and generate recommendations on the role of newer technology in the management of the unanticipated difficult airway. METHODS: A literature search using key words and filters of English language and English abstracted publications from 1990-96 contained in the Medline, Current Contents and Biological Abstracts databases was carried out. The literature was reviewed and condensed and a series of evidence-based recommendations were evolved. CONCLUSIONS: The unanticipated difficult airway occurs with a low but consistent incidence in anaesthesia practice. Difficult direct laryngoscopy occurs in 1.5-8.5% of general anaesthetics and difficult intubation occurs with a similar incidence. Failed intubation occurs in 0.13-0.3% general anaesthetics. Current techniques for predicting difficulty with laryngoscopy and intubation are sensitive, non-specific and have a low positive predictive value. Assessment techniques which utilize multiple characteristics to derive a risk factor tend to be more accurate predictors. Devices such as the laryngeal mask, lighted stylet and rigid fibreoptic laryngoscopes, in the setting of unanticipated difficult airway, are effective in establishing a patient airway, may reduce morbidity and are occasionally lifesaving. Evidence supports their use in this setting as either alternatives to facemask and bag ventilation, when it is inadequate to support oxygenation, or to the direct laryngoscope, when tracheal intubation has failed. Specifically, the laryngeal mask and Combitube have proved to be effective in establishing and maintaining a patent airway in "cannot ventilate" situations. The lighted stylet and Bullard (rigid) fibreoptic scope are effective in many instances where the direct laryngoscope has failed to facilitate tracheal intubation. The data also support integration of these devices into strategies to manage difficult airway as the new standard of care. Training programmes should ensure graduate physicians are trained in the use of these alternatives. Continuing medical education courses should allow physicians in practice the opportunity to train with these alternative devices. 相似文献