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Biomedical subjects

S De Crescenzo

Publications and source records attributed to S De Crescenzo.

6 recordsLinked to original sources
PubMed1992

[The evaluation of the performance of a new-concept screen-film system].

Aim of this work is to show the results of the evaluation of the sensitometric properties of a new Du Pont anti cross-over radiographic film system called Ultra Vision, based on a new film and different YTaO4 undoped screens whose emission is centered at about 335 nm. Fog, contrast, latitude, sensitivity, noise and resolution were tested: the MTFs were obtained by exposing a standard resolution pattern and using the "zero"-frequency step as a knife edge. The image of this knife edge was scanned with a microdensitometer with a 20 microns slit. The results (at 70 kVp with 2.5 mm Al and 2.5 mm Cu total filtration), compared with those of Du Pont conventional radiographic screen-film systems Cronex 10 S/Quanta, show that the new system significantly increases contrast, sensitivity and resolution and will consequently improve, in the clinical use, radiographic image quality.

Equipment Design↗
PubMed1987

[Risks from magnetic fields and radiowaves in equipment for magnetic resonance tomography].

The use of Nuclear Magnetic Resonance Imaging for diagnostic purposes requires a careful analysis of potential risks for workers, patients and public. Aim of this work is a review of the most important biological effects produced by static magnetic fields, radiofrequency fields and field gradients. It's common opinion in fact that the use of magnetic and radiofrequency fields instead of ionizing radiations fields is a safety warranty for patients and workers. Biological experiments in small animals and microorganisms show that also in this case some risks may be expected, due to the trend to employ as much high as possible magnetic fields (and therefore radiofrequency fields). The available data show that the normally used magnetic and radiofrequency fields are below the threshold for somatic effects but denote the necessity of a careful risks/benefit analysis for some patients groups (pacemakers and small surgical metallic implants carriers) and the need of extended and deep studies to specify a possible synergy of different physical agents and incidental oncogenic and teratogenic consequence on the patient.

Animals↗
PubMed1986

[Chernobyl accident: dosimetric evaluation and estimation of risks].

The results of dosimetric evaluations carried out after Chernobyl accident in the Health Physics Department of Niguarda Ca' Granda Hospital (Milan) on air, rain and ground contamination are presented. The results obtained show that the incidence of stochastic late effects, both somatic and genetic, will be so low that practically will not be distinguishable from "natural" incidence.

Accidents↗