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R Herruzo-Cabrera L Malo-González ME Calle Purón MJ Vizcaíno-Alcaide J Del Rey-Calero 《Canadian Metallurgical Quarterly》1993,9(4):442-446
A cross-sectional study was performed to obtain risk factors for hepatitis B disease, HBsAg carriers and immunised personnel, among 2470 workers in a general hospital in Madrid, Spain. The data obtained were analyzed with multiple logistic regression to obtain beta coefficients for variables. The results of the analysis show that being a nurse or being regularly exposed to blood are the most important risk factors for hepatitis B acquisition. The length of time working at the same job activity was also a risk factor. The resulting beta coefficients allow the construction for a hepatitis non-immunised, HBsAg carrier and immunised HBV status, which can select subjects for a hepatitis B vaccination program. 相似文献
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Juey H. Lai Curtis Knudson Leander Hallgren Richard B. Douglas Patrick Griffin 《Polymer Engineering and Science》1985,25(12):778-781
This paper reports the effect of humidity and temperature on the adhesive strength of a pressure sensitive adhesive (Flexbond 150) used to bond Mylar films. It has been found that, ill general, the adhesive strength decreases significantly with an increase in temperature. The effect of humidity on the bonding strength, however, was found to be process dependent. The sample preparation conditions, e.g., press weight for the bonding and the press time, are important in determining the humidity effect. The water sorption isotherm A 24°C for the adhesive was also determined. The amount of water sorbed by the adhesive at 95 percent relative pressure was found to be less than one weight percent. 相似文献
16.
Tipton C.W. Bayne S.B. Griffin T.E. Scozzie C.J. Geil B. Agarwal A.K. Richmond J. 《Electron Device Letters, IEEE》2002,23(4):194-196
This paper reports on the first demonstration of a half-bridge power inverter constructed from silicon carbide gate turn-off thyristors (GTOs) operated in the conventional GTO mode. This circuit was characterized with input bus voltages of up to 600 VDC and 2 A (peak current density of 540 A/cm2) with resistive loads using a pulse-width modulated switching frequency of 2 kHz. We discuss the implications of the thyristor's electrical characteristics and the circuit topology on the overall operation of the half-bridge circuit. This work has determined the conservative critical rate of rise value of the off-state voltage to be 200 V/μs in these devices 相似文献
17.
Tuan Vo-Dinh Guy Griffin David L. Stokes Alan Wintenberg 《Sensors and actuators. B, Chemical》2003,90(1-3):104-111
We describe a multi-functional biochip (MFB), which uses two different types of bioreceptors, including nucleic acid and antibody probes, on a single platform. The multi-functional capability of the MFB device for biomedical diagnostics is illustrated by measurements of DNA probes specific to gene fragments of Bacillus anthracis and antibody probes targeted to Escherichia coli. Calibration curves for monitoring pathogenic species using antibody probes against E. coli and DNA probes for B. anthracis illustrate the capability of the device for medical diagnostics and for quantitative detection of pathogenic agents. 相似文献
18.
Presents a strategy for analyzing social interactive behaviors occurring simultaneously in parallel streams. The standard strategy for representing such data has been interval coding. Interval coding converts the behavioral stream into a sequence of codes representing the behaviors observed in equal length intervals. This strategy is problematic because statistics calculated from interval coded data depend on the arbitrary choice of interval length. An alternative strategy is to represent the behavioral stream in a continuous-time format, using both the sequence of behaviors and their durations. A continuous-time model for social interactive data was applied to observations of mutual gaze between a husband and wife. The analysis uncovered different distributions of event durations in the two partners: The wife looked primarily at the husband and responded sensitively to his gaze behavior, whereas the husband looked primarily away, unresponsive to the wife. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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C Pérault C Schvartz H Wampach JC Liehn MJ Delisle 《Canadian Metallurgical Quarterly》1997,38(8):1234-1242
Superimposition of SPECT and computed tomography (CT) slices from the thoracoabdominal region was achieved without the use of external markers for 14 studies in 13 patients with endocrine carcinoma. Technical feasibility and clinical validation of this retrospective fusion method were assessed. METHODS: Patients had a history of thyroid cancer or of carcinoid tumor. To detect tumor sites, CT scan and dual-isotope tomoscintigraphy were performed, with 99mTc-hydroxymethylene diphosphonate for bone scintigraphy and with 111In-pentetreotide, 131I or 131I-metaiodobenzylguanidine for tumor scintigraphy (TS). A superimposition method previously developed for the pelvic region was adapted to the nonrigid thoraco-abdominal region. CT-bone scintigraphy and CT-TS superimposed images were obtained. Clinical validation of the information obtained from the superimposed images was obtained from surgery or follow-up imaging studies performed after clinical evolution of the disease process. RESULTS: Reliable and reproducible registration was achieved in all patients. CT-TS superimposed images produced accurate localization of abnormal TS foci. Accuracy was limited primarily by variable relative displacements of the thoracoabdominal organs. For 10 sites in 8 patients, localization and/or characterization obtained from CT-TS images was confirmed by a reference technique. Superimposition enabled the localization of tumor sites that otherwise could not have been suspected from CT alone and allowed the characterization of CT suspicious masses and the confirmation of CT positive sites. Nonspecific tumor TS uptake sites were also localized. CONCLUSION: With standard CT and dual-isotope SPECT acquisitions, SPECT-CT fusion is feasible in the thoracoabdominal region without the use of external markers. Fused images were validated in 8 patients for 10 sites. The use of this technique could probably improve the management and care of patients with endocrine carcinoma. 相似文献
20.
Methods to directly and indirectly identify the central sulcus are presented. In the axial plan, direct method is remarkable but obviously requires good visualization of the sulci in the central region. Sulci are readily visible in 90% of the cases on CT scans and in 50% of the cases on MRI. The method can also be applied when tumoral development erases the cerebral sulci by direct lecture of the controlateral rolandic region and right-left transfer. Within the precision limits of the method, it can be considered that the central sulci are symmetrical. The main signs are: the relative morphologies of the superior frontal sulcus and the precentral sulcus, the hook-shaped aspect of the middle part of the central sulcus, the internal end of the central sulcus projection anteriorly to the pars marginalis, the bifid nature of the internal end of the posterior central sulcus contouring the pars marginalis, and the lesser thickness of the posterior central gyrus compared with the precentral gyrus. The indirect method is less precise and is used when the direct method is unsuccessful. The central sulcus is identified on the sagittal images and, using the lateral view of the skull as a reference image, the topographic information is transferred to the axial images. 相似文献