37 research outputs found
Contribution of three components to individual cancer risk predicting breast cancer risk in Italy
We used data from a multicentre case-control study conducted in Italy between 1991 and 1994 on over 2500 cases of breast cancer and a comparable number of controls, and estimates of breast cancer incidence in Italy to compute individual breast cancer risk for Italian women. The estimated probabilities between age 50 and 80 ranged from approximately 5% (for a woman with no family history and low modifiable risk profile) to about 30% (for a woman with young family history and high modifiable risk) on the basis of various women's baseline characteristics. Expected numbers of breast cancer cases using the present model were compared with those based on the USA Gail model, and with the observed ones in the comparison group of the Italian Tamoxifen Trial. These show a closer agreement between the observed and the expected total numbers of breast cancers than the USA Gail model. Thus, the Gail model can be improved for use in other populations by using estimates of incidence and risk which are more appropriate to the target population
Laboratory experiments for Titan's ionosphere : the chemistry of N2+, N+, and N2++ nitrogen ions
N2 is the major neutral componant of Titan's atmosphere, its ionisation by solar radiation and by magnetospheric electron impact is the most important production of ions in Titan's ionosphere. These primary processes not only lead to N+ 2 molecular monocations but also to N+ atomic ions and to N2+ 2 molecular dications, which can pertain some internal or translational excitation. This contribution will summarize our efforts to caracterize in gaz phase laboratory experiments the reactivity of the nitrogen ions with the most important neutral targets of the Titan's atmosphere [1-3]: • N+ 2 + CH4, C2H2, and C2H6 • N+(3P, 1D) + CH4, and C2H4 • N2+ 2 + N2, CH4, and C2H4 In this work, particular attention has been paid on the effect of internal and/or translational excitation of the primary nitrogen ions on the rate constant and branching ratio of these ion-molecule reactions. The results from these studies have been compared to the literature values when available and some significant differences have been found. These new values have been used as input data in 1D models of the Titan's ionosphere to show the effect on the final density profiles of the main ions [4] and to demonstrate the existence of a N2+ 2 dication layer [3]
Photoionization cross section of Xe+ ion in the pure 5p(5) P-2(3/2) ground level
International audienceCoupling an ion trap with synchrotron radiation is shown here to be a powerful approach to measure photoionization cross sections on ionic species relaxed in their ground state. The photoionization efficiency curve of Xe+ ions stored in a Fourier transform ion cyclotron resonance ion trap was recorded at ELETTRA in the 20-23 eV photon energy range. Absolute cross sections were derived by comparison of the photoionization yield of Xe+ with measurements from the ASTRID merged-beam experiment. Multiconfiguration Dirac-Fock calculations were performed for the interpretation of these new data
Expériences de laboratoire pour les ionosphères planétaires: la réactivité des ions
Laboratory experiments for Titan's ionosphere : the chemistry of N2+, N+, and N2++ nitrogen ions
N2 is the major neutral componant of Titan's atmosphere, its ionisation by solar radiation and by magnetospheric electron impact is the most important production of ions in Titan's ionosphere. These primary processes not only lead to N+ 2 molecular monocations but also to N+ atomic ions and to N2+ 2 molecular dications, which can pertain some internal or translational excitation. This contribution will summarize our efforts to caracterize in gaz phase laboratory experiments the reactivity of the nitrogen ions with the most important neutral targets of the Titan's atmosphere [1-3]: • N+ 2 + CH4, C2H2, and C2H6 • N+(3P, 1D) + CH4, and C2H4 • N2+ 2 + N2, CH4, and C2H4 In this work, particular attention has been paid on the effect of internal and/or translational excitation of the primary nitrogen ions on the rate constant and branching ratio of these ion-molecule reactions. The results from these studies have been compared to the literature values when available and some significant differences have been found. These new values have been used as input data in 1D models of the Titan's ionosphere to show the effect on the final density profiles of the main ions [4] and to demonstrate the existence of a N2+ 2 dication layer [3]
Food groups and risk of prostate cancer in Italy
Although several studies have been conducted, the relation between diet and prostate cancer remains unclear. The role of a wide range of foods on the risk of prostate cancer has thus been analyzed in a case-control study conducted in Italy between 1991 and 2002. Cases were 1,294 patients below age 75 years with incident, histologically confirmed carcinoma of the prostate; controls were 1,451 subjects below age 75 years admitted to the same hospitals as cases for a wide spectrum of acute, non-neoplastic conditions. Multivariate odds ratios (ORs) were obtained after allowance for major potential confounding factors, including calorie intake. Among the 19 food groups considered, 4 showed some significant association with prostate cancer risk. A significant trend of increasing risk with more frequent consumption was found for milk and dairy products (OR = 1.2 for highest vs. lowest quintile, p = 0.03) as well as bread (OR = 1.4, p = 0.01), whereas inverse associations were observed for soups (OR = 0.8, p = 0.02) and cooked vegetables (OR = 0.7, p = 0.01). This uniquely large study on prostate cancer and diet in a southern European population confirms that no strong association exists between any specific foods and prostate cancer, apart from an increased risk for milk and dairy products and a possible protective effect of vegetables. (C) 2004 Wiley-Liss, Inc
The management of common bile-duct stones in patients undergoing laproscopic cholecystectomy
The management of suspected and/or unsuspected common bile duct (CBD) stones in patients undergoing laparoscopic cholecystectomy (LC) is controversial. Decisions on whether to perform an open CBD exploration versus employing therapeutic options such as pre-operative/post-operative endoscopic retrograde cholangiography (ERCP) or endoscopic duct exploration are polemic. To determine indications, timing, benefits, and potential morbidity of these approaches, we gathered data on 401 patients undergoing LC within the last 18 months. Indications for preoperative ERCP included jaundice (40%), dilated ducts (28%), elevated amylase (19%) or alkaline phosphatase (21%), suspicion of CBD stones by ultrasound (17%) and ''other'' (17%). Indications for postoperative ERCP were retained stones (33%) and CBD evaluation (67%). Indications for CBD exploration included abnormal cholangiogram (64%), palpable stones (18%), and other (18%). A significant correlation was observed between suspected stones by ultrasound and stones found by ERCP (P < 0.01). For patients in the ''other'' category, preoperative ERCP was universally negative (P = 0.04). Overall ERCP morbidity was 4/59 (6.8%), and the overall failure rate for clearing CBD stones was 2/28 (7.1%). The timing of the ERCP did not affect morbidity/mortality. Multivariate analysis revealed that age (