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81.
RN Younes KC Yin CJ Amino M Itinoshe M Rocha e Silva D Birolini 《Canadian Metallurgical Quarterly》1998,22(1):2-5
The weeping fig, Ficus benjamina (Fb), is a relatively common indoor allergen. Many cases of perennial allergic rhinoconjunctivitis and allergic asthma caused by Fb hypersensitivity are not detected. These patients typically have proven sensitization to housedust mites and do not improve after avoidance of exposure (encasing) and specific immunotherapy. The number of Fb sensitizations is increasing in Germany, which can partly be explained by the cross-reactivity between Hevea brasiliensis (Hb) latex and Fb and the rapidly increasing number of mostly occupational latex allergies. But Fb itself is a potential sensitizer which is widely spread as ornamental plant in homes and offices. As relevant indoor allergen Fb ranks third after housedust mites and pets but before molds among our allergy patients. For diagnosis, prick-tests with Fb-latex seem to be more sensitive than in vitro-methods (RAST, CAPRAST). Fb plants should not be kept in the homes of atopic individuals or persons with latex (Hb) allergy. 相似文献
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84.
DJ MacGowan MN Janal WC Clark RN Wharton RM Lazar RL Sacco JP Mohr 《Canadian Metallurgical Quarterly》1997,49(1):120-125
BACKGROUND: Questionnaire-based surveys from several countries have consistently detected adverse health associated with home dampness and mould growth. METHODS: To test the validity of questions commonly used to indicate the presence of indoor mould, questionnaires were administered in 403 homes where dust samples were taken for viable fungi and air samples for ergosterol. RESULTS: Geometric mean concentrations of the total viable fungi were 255 (SE 116) x 10(3) CFU/g when mouldy odours were reported and 155 (SE 55) when odours were not reported (P = 0.01). Similarly, reported water damage was associated with a 50% increase (P = 0.06). Geometric mean concentrations of the predominantly indoor-source fungi, Aspergillus plus Penicillium, were twice as high when mould or mildew was reported than when not mentioned (P = 0.01). The presence of reported mould or water damage was unrelated to the presence of detectable levels of ergosterol. There was evidence for reporting bias: in the presence of low concentrations of viable fungi in dust, respondents reporting allergies were more likely to report visible mould growth (odds ratio [OR] = 1.8, 95% confidence interval [CI]: 0.9-3.5, P = 0.10. In the presence of elevated concentrations of dust fungi, respondents who smoked were less likely to report visible mould growth, (OR = 0.4, 95% CI: 0.2-0.7, P = 0.005). CONCLUSIONS: Reported mould, water damage, and mouldy odours were associated with elevated levels of indoor fungi. However, inaccuracy was high and there was evidence of a systematic reporting bias. Future research should concentrate on developing accurate objective measures of exposure to fungi, and then use this information to develop valid questionnaires. Currently, objective measures not questionnaires, are recommended to clarify the health effects of indoor fungi. 相似文献
85.
The surfaces of air-oxidized Pd-15Rh alloys have been examined by X-ray photoelectron spectroscopy (XPS) and by Raman spectroscopy. The XPS results indicate that the near-surface region of samples oxidized in the temperature range 1075 to 1125 K contains Pd in both the +2 and +1 oxidation states and Rh in the +3 oxidation state. The ratio of Pd (I) to Rh (III) is found to be 11. Raman spectra confirm that two Pd-containing phases, PdO and PdRhO2, are present in the near-surface region and eliminate the possibility that Rh2O3 is present. Also, a resonant Raman effect is observed in anhydrous PdO for exciting wavelengths in the vicinity of 500 nm. 相似文献
86.
Bound-state beta decay of highly ionized atoms 总被引:1,自引:0,他引:1
87.
Matan O. Baird H.S. Bromley J. Burges C.J.C. Denker J.S. Jackel L.D. Le Cun Y. Pednault E.P.D. Satterfield W.D. Stenard C.E. Thompson T.J. 《Computer》1992,25(7):59-63
A neural network algorithm-based system that reads handwritten ZIP codes appearing on real US mail is described. The system uses a recognition-based segmenter, that is a hybrid of connected-components analysis (CCA), vertical cuts, and a neural network recognizer. Connected components that are single digits are handled by CCA. CCs that are combined or dissected digits are handled by the vertical-cut segmenter. The four main stages of processing are preprocessing, in which noise is removed and the digits are deslanted, CCA segmentation and recognition, vertical-cut-point estimation and segmentation, and directly lookup. The system was trained and tested on approximately 10000 images, five- and nine-digit ZIP code fields taken from real mail 相似文献
88.
SA Petrill K Saudino SS Cherny RN Emde DW Fulker JK Hewitt R Plomin 《Canadian Metallurgical Quarterly》1998,69(1):68-74
Two definitions of normality ("isolated" or "correlated") are considered. The boundaries of "isolated" normality were determined by a statistical procedure, whereas the "correlated" approach was related to a clinical or predictive definition. In the latter case, the biological variations were considered abnormal if they implied a hazard with some significant future ailment as a risk factor. In this pragmatic approach, the upper limit of normal/abnormal variations is the point beyond which medical strategy is related to the most expected benefit when applied to a definite population or to an individual patient. The capacity of a diagnostic test to discriminate between patients with a defined risk and those without risk depends strictly on the value of the parameter chosen. In medical care for the prevention of vascular complications in diabetic patients or with foetal risks in pregnant women, the limits of the so-called normal range of glycaemia and other parameters should be determined according to the objective of the preventive and/or therapeutic measures to be prescribed. 相似文献
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Axial dispersion coefficients (E) in the liquid phase have been measured by unsteady tracer response methods in a 15 cm internal diameter reciprocating plate bubble column, using air and water in countercurrent and cocurrent flow. The operating variables studied were amplitude (0.6–1.27 cm) and frequency (0–5 Hz) of reciprocation, and the superficial velocities of the liquid and gas phases and the spacing between plates. Three types of plate were studied; conventional Karr-type plates with perforation diameters 1.43 cm, plates with smaller (0.635 cm) perforations, and single-perforation (doughnut) plates with internal diameter 7 cm. Measured values of E ranged from about 1 cm2/s to a maximum of 116 cm2/s. In general, the plates with 0.635 cm perforations gave the smallest values of E while the largest values of E were obtained with the doughnut plates, due to vortex ring shedding. The single liquid phase data for the three types of plate were approximately consistent with the correlation of Stevens and Baird (1990). The gas-liquid flow results were interpreted in terms of several different hydrodynamic effects. 相似文献