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S Orsini

Publications and source records attributed to S Orsini.

At least 37 records · Page 2Linked to original sources
PubMed1990

[NIOBI-X filter: reduction of patient exposure and effect on image quality].

Patient protection against ionizing radiation has become more and more important and the subject has been included in all the latest ICRP publications. Recently a 50 microns Niobium filter (NIOBI-X) has come out, which, installed on tungsten anode X-ray apparatuses, allows patient dose reduction by absorbing the radiation which does not contribute to the image. In order to verify the NIOBI-X actual effect on image quality and on patient dose reduction, image resolution, image contrast and patient exposure (air-Kerma) were measured using a bone-equivalent stepped wedge. The NIOBI-X, added to the total filtration of the X-ray apparatus, allows an air-Kerma reduction of about 50% from 60 to 130 kV. In the case of bone-equivalent material exposure the filter causes a slight contrast loss and does not affect, or even improves, image resolution. Before choosing the NIOBI-X filter for all the X-ray apparatuses a cost-benefit analysis should of course be made by evaluating results and cost related to other kinds of filter. With particular regard to Aluminium filters, whose prices are far lower than Niobium ones, it has to be pointed out that: 1) in order to have the same air-Kerma reduction the Aluminium filter thickness must be quite heavy (2.8 mm) which causes practical problems of use; 2) the Aluminium filter causes image quality loss especially at lower kVs.

Filtration↗
PubMed1989

In vivo effect of eflornithine (DFMO) and some related compounds on Leishmania infantum preliminary communication.

An in vivo method was used to test the effect of eflornithine (DFMO) and five related compounds on Leishmania infantum amastigotes. Treatment with 100 mg/kg sc for 5 days of Leishmania infected Balb/c mice yielded a parasite inhibition ranging from 56% (compound 2, "reverse arginine") to 85% (eflornithine), these values being lower than that obtained with the reference compound Glucantime (93%). In long-term treatment (40 days) the two selected compounds, eflornithine and 3 ("reverse homoarginine"), failed to cure the animals. However, in dose response experiments these drugs showed to be effective at very low doses when compared with Glucantime, thus suggesting that they might be of potential value in the chemotherapy of leishmaniases.

Animals↗
PubMed1983

Percutaneous blind biopsy versus laparoscopy with guided biopsy in diagnosis of cirrhosis. A prospective, randomized trial.

A prospective controlled study of the diagnostic accuracy of blind percutaneous liver biopsy in comparison to laparoscopy plus guided biopsy for the recognition or exclusion of cirrhosis has been performed. One hundred twenty-six patients with a clinical diagnosis of chronic, diffuse, well-compensated liver disease were randomized into two groups and submitted either to percutaneous blind liver biopsy (PB: 64 patients) or to laparoscopy with guided biopsy (LB: 62 patients), in order to assess the accuracy of either procedure in diagnosing cirrhosis. PB correctly recognized or ruled out cirrhosis in 52 patients (82%). Inconclusive results were mostly false negative, as demonstrated by the presence on endoscopy of esophageal varices or by subsequent LB. LB demonstrated presence or absence of cirrhosis in all patients. The difference between the rate of accurate results of the two procedures is statistically significant. It is concluded that in patients without esophageal varices, LB should be the investigation of choice for the assessment of liver structure since the presence of cirrhosis can be missed in up to 20% of cases by PB.

Adult↗
PubMed1982

[Classification and staging of soft tissue sarcomas].

The difficulties of classification and staging of the soft tissue sarcomas have always represented a tough task. The Authors present a review of the existing literature and the classification and staging which in their view are more suitable to the present therapeutic needs. They stress the importance of the histocytopathological information together with the other informations, such as the localization and the size of the tumour, the sex and age of the patient.

Adult↗
PubMedDate not supplied

[The doses absorbed by the patients and the exposure of the operators in dental radiodiagnosis].

The present paper reports an updated dosimetry of dental radiology since it presents the data relative to 7 radiological techniques. The doses to 9 organs were measured on a Randoman phantom using TLD (4 in each chosen cavity) for lenses, tongue, cervical vertebrae (C2), thyroid, ovaries, uterus and testes. The examinations were subsequently repeated after applying X-ray shields to the phantom. The main conclusions follow: a) local doses are never negligible but can be really high, especially for tongue (1.880 mGy), thyroid (1.011 mGy), and C2 (0.699 mGy); b) X-ray shields for lenses, ovaries, uterus and testes have proven to be unnecessary; in a more general context, X-ray shields should be evaluated by the Health Physics Dept., especially relative to radiation leaks from the X-ray tube. As for the thyroid, X-ray shields have proven very useful but can result in repeated acquisitions because of possible interference with the radiological image; c) technicians' risk, in the present experimental conditions, does not exceed the threshold values recommended by Italian laws. At any rate, the use of fixed or mobile shieldings should always be evaluated while keeping in mind the specific working conditions in radiology departments.

Female↗
PubMedDate not supplied

[Sources of ionizing radiation in dwellings].

According to recent surveys made by the International Commission on Radiological Protection (ICRP) and the World Health Organization (WHO), it has been estimated that in temperate regions people spend only 20% of their time outdoors and spend the remaining 80% indoors (homes, schools, other buildings). It is therefore important to establish whether radiation sources exist inside buildings in order to assess risk for the population. The 238U and 232Th radioactive chains are of particular importance because of Radon and Radon daughter production and 40K as component of building materials. It has been estimated that about 4.5% of lung cancers observed in the population are associated with exposure to Radon daughters. In order to comply with international regulations it is estimated that 1.5% of the existing dwellings in temperate regions need to be improved.

Air Pollution, Radioactive↗