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101.
L Ohno-Machado JH Gennari SN Murphy NL Jain SW Tu DE Oliver E Pattison-Gordon RA Greenes EH Shortliffe GO Barnett 《Canadian Metallurgical Quarterly》1998,5(4):357-372
Carboxylate and sulfate groups were introduced at the surface of poly(ethylene) (PE) samples. This was accomplished by coating and immobilizing sodium 10-undecenoate (C11(:)) and 10-undecene sulfate (S11(:)) on the polymer by means of an argon plasma treatment. The composition of the coated surfactant layer was proportional to the composition of the coating solution. The thickness of the surfactant layer on the surface of PE samples, which were precoated from an aqueous solution with a total surfactant concentration of 0.30 M, was about 55 A. The presence of carboxylate and sulfate groups after plasma treatment of the precoated surfaces was confirmed by X-ray photoelectron spectroscopy (XPS). About 20% of the initial amount of functional groups of the coated surfactants was retained at the PE surface. The ratio of carboxylate/sulfate groups at the plasma treated surfaces was dependent on the composition of the precoated surfaces. The minimum surface density of these groups on the resulting samples was about one group per 40 A2. 相似文献
102.
FI Meredith RT Riley CW Bacon DE Williams DB Carlson 《Canadian Metallurgical Quarterly》1998,61(8):1034-1038
The purpose of this study was (i) to determine whether pure fumonisin B1 could be incorporated into, recovered, and detected by high-pressure liquid chromatographic analysis from the semipurified Oregon test diet (OTD) used in rainbow trout feeding studies, and (ii) to determine if the incorporated fumonisin B1 was biologically available using the change in free sphingoid bases in liver, kidney, and serum as a mechanism-based biomarker. The results indicate that fumonisin is not easily quantified in the OTD. Recoveries ranged from 12 to 81% of the calculated concentrations based on the fumonisin B1 added to the OTD. However, the fumonisin B1 in the OTD was readily absorbed and biologically active as evidenced by marked increases in free sphinganine in liver, kidney, and serum. The magnitude of the increase in free sphinganine at 100 ppm in the OTD was comparable to that known to be associated with liver toxicity in rats, pigs, and ponies. 相似文献
103.
DE Epner AW Partin JA Schalken JT Isaacs DS Coffey 《Canadian Metallurgical Quarterly》1993,53(9):1995-1997
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression is increased in Dunning R-3327 rat prostatic adenocarcinoma cell lines relative to normal rat ventral prostate tissue. GAPDH expression closely correlates with cell motility of Dunning prostate cancer cell lines and accurately distinguishes cell lines with high metastatic potential from those with low metastatic potential. Increased GAPDH expression in the cancer cell lines is not simply related to increased growth rate, since rapidly proliferating normal prostate tissue did not exhibit elevated GAPDH expression. 相似文献
104.
PH Allaire JM Messick JE Oesterling DE Byer RP Myers MM Lieber RC Chantigian JO Welna DE Patterson ML Blute 《Canadian Metallurgical Quarterly》1992,67(11):1031-1041
In a prospective, randomized study, continuous infusion of epidural fentanyl citrate (group E) was compared with patient-controlled intravenously administered morphine sulfate (group P) for analgesia in 66 men after radical retropubic prostatectomy. Although both methods provided satisfactory analgesia, the mean comfort level scores were lower (that is, greater comfort) in group E than in group P at all observation times. The difference in mean resting comfort level scores between groups E and P was statistically significant (P < or = 0.05) at 9 of the 11 observation times. In addition, significant differences in comfort level scores were noted at 8 of the 11 observation times during deep breathing, 5 of 11 during coughing, and 3 of 9 during ambulation. Maximal and minimal comfort level scores recorded by each patient during the course of the study were significantly lower (that is, less pain) in group E than in group P for all four categories of activity. The percentage of patients who reported no pain was significantly higher in group E than in group P at 9 of 11 observation times during resting and 5 of 11 observation times during deep breathing. No significant differences were noted in side effect profiles or duration of hospital stay. In summary, when two effective methods of analgesia used after radical retropubic prostatectomy were compared prospectively, patients who received epidural infusion of fentanyl were more comfortable than those with patient-controlled intravenous administration of morphine, as evidenced by lower mean, maximal, and minimal comfort level scores and a greater proportion of patients with complete relief of pain. 相似文献
105.
106.
Acute care facilities are no longer viewed as the center of the health care network. Efforts to reduce hospital length of stay will continue to spur the growth of care delivered in homes. With the downsizing of many hospitals, the need for nurses in acute care settings will decline. Many acute care nurses are finding themselves seeking employment opportunities in home health care settings. The purpose of this study was to examine nurses' experiences when they change from hospital-based practice to home health care nursing. The qualitative mode of inquiry was used to conduct taped-recorded interviews of 25 baccalaureate-prepared nurses in a large metropolitan area. Stressors experienced by the nurses were identified as well as adaptations required to minimize role stress. Continuing education programs can provide information and skills needed to improve nurses' competencies to function in a health care system projected to be more community-based, which includes home health care. 相似文献
107.
RM Goncalves JA Harris DE Rivera 《Canadian Metallurgical Quarterly》1998,64(6):493-7; discussion 497-8
Patients with biliary dyskinesia have symptoms consistent with biliary colic and an abnormal gallbladder ejection fraction (GEF) in the absence of cholelithiasis. Cholecystokinin hepatobiliary scan quantifies gallbladder function and may assist in selecting patients with acalculous biliary pain who would benefit from cholecystectomy. Seventy-eight patients with an abnormal GEF (< 35%) on cholecystokinin hepatobiliary scan without cholelithiasis were studied retrospectively. Patients were divided into groups based on diagnosis and treatment. In Group I, the patients who underwent cholecystectomy, 80 per cent (35 of 44) had complete symptomatic resolution whereas the remaining 20 per cent (9 of 44) had symptomatic improvement. Pathology reports demonstrated chronic cholecystitis in 95 per cent of specimens. Group II were patients with symptoms attributable to biliary dyskinesia, but did not undergo cholecystectomy. Persistence of symptoms was noted in 75 per cent (18 of 24) of patients whereas 25 per cent (6 of 24) had symptomatic resolution without any treatment. Group III consisted of patients with an abnormal ejection fraction who had improvement of symptoms after treatment for an alternative diagnosis (n = 10). These findings suggest that an abnormal ejection fraction does not always indicate gallbladder disease. Alternative diagnoses must be investigated and treated. Patients with persistent biliary type symptoms in combination with an abnormal GEF in the absence of other attributable causes can expect a favorable response to cholecystectomy. 相似文献
108.
DE Low 《Canadian Metallurgical Quarterly》1998,12(3):613-30, viii
During the last decade there has been an unexpectedly rapid evolution of antimicrobial resistance in the respiratory pathogens for community- and hospital-acquired pneumonia. In order to choose the most optimal therapy for their patients, it is essential that physicians be aware of the prevalence and mechanisms of resistance and their implications on the effectiveness of the various antimicrobials. 相似文献
109.
110.
J Heller AC Kolbert R Larsen M Ernst T Bekker M Baldwin SB Prusiner A Pines DE Wemmer 《Canadian Metallurgical Quarterly》1996,5(8):1655-1661
Conformational changes in the prion protein (PrP) seem to be responsible for prion diseases. We have used conformation-dependent chemical-shift measurements and rotational-resonance distance measurements to analyze the conformation of solid-state peptides lacking long-range order, corresponding to a region of PrP designated H1. This region is predicted to undergo a transformation of secondary structure in generating the infectious form of the protein. Solid-state NMR spectra of specifically 13C-enriched samples of H1, residues 109-122 (MKHMAGAAAAGAVV) of Syrian hamster PrP, have been acquired under cross-polarization and magic-angle spinning conditions. Samples lyophilized from 50% acetonitrile/50% water show chemical shifts characteristic of a beta-sheet conformation in the region corresponding to residues 112-121, whereas samples lyophilized from hexafluoroisopropanol display shifts indicative of alpha-helical secondary structure in the region corresponding to residues 113-117. Complete conversion to the helical conformation was not observed and conversion from alpha-helix back to beta-sheet, as inferred from the solid-state NMR spectra, occurred when samples were exposed to water. Rotational-resonance experiments were performed on seven doubly 13C-labeled H1 samples dried from water. Measured distances suggest that the peptide is in an extended, possibly beta-strand, conformation. These results are consistent with the experimental observation that PrP can exist in different conformational states and with structural predictions based on biological data and theoretical modeling that suggest that H1 may play a key role in the conformational transition involved in the development of prion diseases. 相似文献