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61.
There were 35 oesophageal intubations in the first 2000 incidents reported to the Australian Incident Monitoring Study (AIMS). These reports confirm existing impressions that misplacement of the endotracheal tube can occur in trained as well as untrained hands, and that auscultation is an unreliable test. On the other hand, the value of capnography is emphasised, with no false positives in the 16 cases in which the instrument was used. There was one false negative. Over the 4 years of the AIMS study, reports have declined in frequency. It is possible that the early detection of oesophageal intubation by capnography has altered its status to the extent that anaesthetists no longer regard it as a "critical" incident. It is highly recommended that the presence of the expected concentration of carbon dioxide in expired air be confirmed by capnography immediately after any endotracheal intubation. 相似文献
62.
Alex L. Riley Sarah E. Pepper Adam J. Canner Solomon F. Brown Mark D. Ogden 《分离科学与技术》2018,53(1):22-35
Work has been carried out screening hydrometallurgical resins for application in the valorization of industrially produced jarosite. Of the seven resins tested, anion exchange resins performed poorly for valuable metal recovery. Purolite S950+ and S957, along with a strong acid resin, show good extraction properties, but are selective for Fe3+ over the other (divalent) metals. Purolite S930+ (iminodiacetic acid-functionalized resin) demonstrates selectivity for Cu2+ over Fe3+, but poor selectivity for Ni2+, Zn2+, and Co2+. Dowex M4195 (bispicolylamine-functionalized resin) demonstrates promise for extracting metals of value away from a mixed metal pregnant liquor solution (PLS). A three-stage column-based recovery process is proposed for jarosite leachate treatment. 相似文献
63.
A systematic preparation of alkyl substituted phenoxyphosphazene polymers was performed and their gas transport properties determined. In this study, phosphazenes substituted with 4-methylphenol, 4-ethylphenol, and 4-isopropylphenol are reported. An additional polymer substituted with 4-tert-butylphenoxy-1-ethanol also was synthesized in this work. Data derived for these materials, including chemical, thermal and gas transport characterization, were compared to previous reports discussing poly[bis-phenoxyphosphazene] and its analog with tert-butyl substitution: poly[bis-(4-tert-butylphenoxy)phosphazene]. The tert-butyl moiety influences orderly chain packing, presumably through steric hindrance that can influence aromatic π-stacking. For the new poly[(alkylphenoxy)phosphazenes], semicrystallinity is maintained and the added steric bulk serves to decrease the polymer glass transition temperature (Tg) and increase both permeability and selectivity for the gas pairs: O2/N2 and CO2/CH4. Removal of the tert-butyl moiety from the immediate vicinity of the backbone through a flexible spacer serves to depress the Tg as compared to poly[bis-(4-tert-butylphenoxy)phosphazene], but provides no performance enhancement for gas transport. 相似文献
64.
Constraints on biological effects of weak extremely-low-frequency electromagnetic fields 总被引:3,自引:0,他引:3
RK Adair 《Canadian Metallurgical Quarterly》1991,43(2):1039-1048
65.
Williams P.J. Walker R.G. Charles P.M. Ogden R. Wood A.K. Carr N. Carter A.C. 《Electronics letters》1991,27(10):809-810
The fabrication and characterisation of monolithically integrated OEIC transceivers for use in optical subscriber access links are reported. A design incorporating DFB lasers, wavelength duplexers and a monitor photodiode, specific to the TPON/BPON passive optical network configuration is presented.<> 相似文献
66.
RK Sommers 《Canadian Metallurgical Quarterly》1998,87(1):187-198
It has long been recognized that a basic dimension to the lexical organization of the brain is semantic, and some brain mapping studies have indicated that the brain fields are distinctly different from some grammatical classes. Findings from the present investigation showed consistent relationships between 29 aphasic adults' performances on tasks involving graphic and gestural skills and those involving sequential recall of spoken words from different word categories. Each adult received the Porch Index of Communication Abilities which relies upon the physical manipulation of objects to assess verbal, gestural, and graphic abilities. Scores on a test requiring recall of word strings of nouns, verbs, adverbs, adjectives, or prepositions were used to predict the subscale scores from the Graphic and Gestural factors of the index. Recall scores for verb and preposition were predictive of the aphasic subjects' performances on the Graphic subscale, and noun and preposition scores were predictors of subjects' scores on the Gestural subscale. The results are related to other research showing that verb and preposition skills are predictive of fine motor abilities of children with communication disorders and brain-mapping studies. Some discussion centers on possible overlapping functions of brain activity involving word categories, language, and fine motor skills. 相似文献
67.
Ionizing radiation is believed to stimulate the repopulation of squamous carcinoma cells that survive the early portion of a fractionated course of radiotherapy. To characterize any intrinsic radiation-induced adaptive response and to examine whether epidermal growth factor (EGF) influences this response, A431 and 183A cells were irradiated with repeated daily exposures of 0.5-0.75 Gy and then grown in monolayer culture for 7 days with or without EGF at a 1 ng/ml concentration. Cell numbers were quantified using a microtiter dye-reduction assay. EGF alone caused approximately 70% and 30% growth inhibition of human SC A431 and 183A cells, respectively. Although radiation alone did not affect proliferative rates in these conditions, radiation eliminated the EGF-related growth inhibition in both cell lines. This effect was dose dependent in single radiation exposure experiments. Cell cycle analyses indicated that EGF initially promoted entry into S-phase 3 days after treatment but caused a G1-S block after 7 days. Treatment with radiation recruited cells into S-phase and G2-M, an effect which was sustained 7 days after treatment, overriding the influence of EGF. Radiation-induced modulation of the response of human squamous carcinoma cells to EGF in vitro after single and repeated radiation exposures suggests a proliferation response that may underlie enhanced repopulation of tumor clonogens in vivo. 相似文献
68.
69.
The combination of ifosfamide, carboplatin and etoposide (modified ICE), was evaluated for its toxicity and activity in relapsed or refractory aggressive non-Hodgkin's lymphoma. Twenty patients, 14-69 years of age, with relapsed (19 cases) or refractory (one case) aggressive non-Hodgkin's lymphoma were treated with modified ICE therapy, consisting of ifosfamide 6 g/m2 (1.2 g/m2 day 1-5), carboplatin 400 mg/m2 (day 1) and etoposide 500 mg/m2 (100 mg/m2 day 1-5). The regimen was repeated at approximately 28-day intervals. All patients had undergone a doxorubicin-containing regimen before modified ICE therapy. Median total dose of previously received doxorubicin was 406 mg/m2 (range: 200-825 mg/m2). The median interval from diagnosis to modified ICE therapy was 9.4 months (range: 3.6-121 months). Two patients achieved CR and five achieved PR out of 16 patients with measurable lesions (response rate 43.8%; 95% confidence interval 19.0-68.6%). Median overall survival was 227 days (range: 41-552 days) from the start of modified ICE therapy. Myelosuppression was the most serious toxicity, namely 16 patients (80%) and 11 patients (55%) showed grade 4 neutropenia and grade 4 thrombocytopenia after the first course, respectively. Modified ICE therapy might be an active regimen with acceptable toxicity as a salvage chemotherapy in aggressive non-Hodgkin's lymphoma. 相似文献
70.
WR Kirkpatrick RK McAtee SG Revankar AW Fothergill DI McCarthy MG Rinaldi TF Patterson 《Canadian Metallurgical Quarterly》1998,36(5):1330-1332
A simple screening method for fluconazole susceptibility of Cryptococcus neoformans using 2% dextrose Sabouraud dextrose agar (SabDex) with fluconazole was compared to the National Committee for Clinical Laboratory Standards (NCCLS) broth macrodilution method. By this method, fluconazole-susceptible C. neoformans isolates are significantly smaller on medium with fluconazole than on fluconazole-free medium. Isolates with decreased susceptibility have normal-size colonies on medium containing fluconazole. The 48-h NCCLS broth macrodilution MICs (NCCLS MICs) for isolates with normal-size colonies on 8- or 16-microg/ml fluconazole plates were predicted to be > or =8 or > or =16 microg/ml, respectively. On medium with 16 microg of fluconazole per ml, all strains (84 of 84) for which the NCCLS MICs were <16 microg/ml were correctly predicted, as were all isolates (7 of 7) for which the MICs were > or =16 microg/ml. Agar dilution appears to be an effective screening method for fluconazole resistance in C. neoformans. 相似文献