| 1. |
- Oellers, D., et al.
(författare)
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Polarizing a stored proton beam by spin flip?
- 2009
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Ingår i: Physics Letters B. - : Elsevier. - 0370-2693 .- 1873-2445. ; 674:4-5, s. 269-275
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Tidskriftsartikel (refereegranskat)abstract
- We discuss polarizing a proton beam in a storage ring, either by selective removal or by spin flip of the stored ions. Prompted by recent, conflicting calculations, we have carried out a measurement of the spin-flip cross section in low-energy electron–proton scattering. The experiment uses the cooling electron beam at COSY as an electron target. The measured cross sections are too small for making spin flip a viable tool in polarizing a stored beam. This invalidates a recent proposal to use co-moving polarized positrons to polarize a stored antiproton beam.
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| 2. |
- Tajkumar, T, et al.
(författare)
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Cervical carcinoma and sexual behavior: collaborative reanalysis of individual data on 15,461 women with cervical carcinoma and 29,164 women without cervical carcinoma from 21 epidemiological studies
- 2009
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Ingår i: Cancer Epidemiology Biomarkers & Prevention. - 1538-7755. ; 18:4, s. 1060-1069
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Tidskriftsartikel (refereegranskat)abstract
- High-risk human papillomavirus (HPV) types cause most cervical carcinomas and are sexually transmitted. Sexual behavior therefore affects HPV exposure and its cancer sequelae. The International Collaboration of Epidemiological Studies of Cervical Cancer has combined data on lifetime number of sexual partners and age at first sexual intercourse from 21 studies, or groups of studies, including 10,773 women with invasive cervical carcinoma, 4,688 women with cervical intraepithelial neoplasia grade 3 (CIN3)/carcinoma in situ, and 29,164 women without cervical carcinoma. Relative risks for invasive cancer and CIN3 were estimated by conditional logistic regression. Risk of invasive cervical carcinoma increased with lifetime number of sexual partners (P for linear trend <0.001). The relative risk for > or =6 versus 1 partner, conditioned on age, study, and age at first intercourse, was 2.27 [95% confidence interval (95% CI), 1.98-2.61] and increased to 2.78 (95% CI, 2.22-3.47) after additional conditioning on reproductive factors. The risk of invasive cervical carcinoma increased with earlier age at first intercourse (P for linear trend <0.001). The relative risk for age at first intercourse < or =14 versus > or =25 years, conditioned on age, study, and lifetime number of sexual partners was 3.52 (95% CI, 3.04-4.08), which decreased to 2.05 (95% CI, 1.54-2.73) after additional conditioning on reproductive factors. CIN3/carcinoma in situ showed a similar association with lifetime number of sexual partners; however, the association with age at first intercourse was weaker than for invasive carcinoma. Results should be interpreted with caution given the strong correlation between sexual and reproductive factors and the limited information on HPV status.
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| 3. |
- Rajkumar, T, et al.
(författare)
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Carcinoma of the cervix and tobacco smoking: Collaborative reanalysis of individual data on 13,541 women with carcinoma of the cervix and 23,017 women without carcinoma of the cervix from 23 epidemiological studies - International collaboration of epidemiological studies of cervical cancer
- 2006
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136. ; 118:6, s. 1481-1495
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Tidskriftsartikel (refereegranskat)abstract
- Tobacco smoking has been classified as a cause of cervical cancer, but the effect of different patterns of smoking on risk is unclear. The International Collaboration of Epidemiological Studies of Cervical Cancer has brought together and combined individual data on 13,541 women with and 23,017 women without cervical carcinoma, from 23 epidemiological studies. Relative risks (RRs) and 95% confidence intervals (CIs) of carcinoma of the cervix in relation to tobacco smoking were calculated with stratification by study, age, sexual partners, age at first intercourse, oral contraceptive use and parity. Current smokers had a significantly increased risk of squamous cell carcinoma of the cervix compared to never smokers (RR = 1.60 (95% CI: 1.48-1.73), p < 0.001). There was increased risk for past smokers also, though to a lesser extent (RR = 1.12 (1.01-1.25)), and there was no clear trend with time since stopping smoking (p-trend = 0.6). There was no association between smoking and adenocarcinoma of the cervix (RR = 0.89 (0.74-1.06) and 0.89 (0.72-1.10) for current and past smokers respectively), and the differences between the RRs for smoking and squamous cell and adenocarcinoma were statistically significant (current smoking p < 0.001 and past smoking p = 0.01). In current smokers, the RR of squamous cell carcinoma increased with increasing number of cigarettes smoked per day and also with younger age at starting smoking (p < 0.001 for each trend), but not with duration of smoking (p-trend = 0.3). Eight of the studies had tested women for cervical HPV-DNA, and in analyses restricted to women who tested positive, there was a significantly increased risk in current compared to never smokers for squamous cell carcinoma (RR = 1.95 (1.43-2.65)), but not for adenocarcinoma (RR = 1.06 (0.14-7.96)). In summary, smokers are at an increased risk of squamous cell but not of adenocarcinoma of the cervix. The risk of squamous cell carcinoma increases in current smokers with the number of cigarettes smoked per day and with younger age at starting smoking.
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| 4. |
- Hautmann, R, et al.
(författare)
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Urinary diversion
- 2006
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Ingår i: Bladder Tumors. ; , s. 239-239
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 5. |
- Kolm, Niclas, et al.
(författare)
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Can sexual selection drive female life histories? : A comparative study on Galliform birds
- 2007
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Ingår i: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 20:2, s. 627-638
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Tidskriftsartikel (refereegranskat)abstract
- Sexual selection has been identified as a major evolutionary force shaping male life history traits but its impact on female life history evolution is less clear. Here we examine the impact of sexual selection on three key female traits (body size, egg size and clutch size) in Galliform birds. Using comparative independent contrast analyses and directionaldiscreteanalyses, based on published data and a new genera-level supertree phylogeny of Galliform birds, we investigated how sexual selection [quantified as sexual size dimorphism (SSD) and social mating system (MS)] affects these three important female traits. We found that female body mass was strongly and positively correlated with egg size but not with clutch size, and that clutch size decreased as egg size increased. We established that SSD was related to MS, and then used SSD as a proxy of the strength of sexual selection. We found both a positive relationship between SSD and female body mass and egg size and that increases in female body mass and egg size tend to occur following increases in SSD in this bird order. This pattern of female body mass increases lagging behind changes in SSD, established using our directionaldiscreteanalysis, suggests that female body mass increases as a response to increases in the level of sexual selection and not simply through a strong genetic relationship with male body mass. This suggests that sexual selection is linked to changes in female life history traits in Galliformes and we discuss how this link may shape patterns of life history variation among species.
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| 6. |
- Johansson, Mattias, et al.
(författare)
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Circulating concentrations of folate and vitamin B12 in relation to prostate cancer risk : results from the European prospective investigation into cancer and nutrition study
- 2008
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Ingår i: Cancer Epidemiol Biomarkers Prev. - 1055-9965. ; 17:2, s. 279-285
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Tidskriftsartikel (refereegranskat)abstract
- Background: Determinants of one-carbon metabolism, such as folate and vitamin B12, have been implicated in cancer development. Previous studies have not provided conclusive evidence for the importance of circulating concentrations of folate and vitamin B12 in prostate cancer etiology. The aim of the present study was to investigate the relationship between prostate cancer risk and circulating concentrations of folate and vitamin B12 in a large prospective cohort. Methods: We analyzed circulating concentrations of folate and vitamin B12 in 869 cases and 1,174 controls, individually matched on center, age, and date of recruitment, nested within the European Prospective Investigation into Cancer and Nutrition cohort. Relative risks (RR) for prostate cancer were estimated using conditional logistic regression models. Results: Overall, no significant associations were observed for circulating concentrations of folate (Ptrend = 0.62) or vitamin B12 (Ptrend = 0.21) with prostate cancer risk. RRs for a doubling in folate and vitamin B12 concentrations were 1.03 [95% confidence interval (95% CI), 0.92-1.16] and 1.12 (95% CI, 0.94-1.35), respectively. In the subgroup of cases diagnosed with advanced stage prostate cancer, elevated concentrations of vitamin B12 were associated with increased risk (RR for a doubling in concentration, 1.69; 95% CI, 1.05-2.72, Ptrend = 0.03). No other subgroup analyses resulted in a statistically significant association. Conclusion: This study does not provide strong support for an association between prostate cancer risk and circulating concentrations of folate or vitamin B12. Elevated concentrations of vitamin B12 may be associated with an increased risk for advanced stage prostate cancer, but this association requires examination in other large prospective studies. (Cancer Epidemiol Biomarkers Prev 2007;17(2):279–85)
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| 7. |
- Gasche, C, et al.
(författare)
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Guidelines on the diagnosis and management of iron deficiency and anemia in inflammatory bowel diseases
- 2007
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Ingår i: Inflammatory Bowel Diseases. - : Oxford University Press (OUP). - 1078-0998 .- 1536-4844. ; 13:12, s. 1545-1553
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Tidskriftsartikel (refereegranskat)abstract
- Anemia is a common complication of inflammatory bowel diseases. An international working party has formed and developed guidelines for evaluation and treatment of anemia and iron deficiency that should serve practicing gastroenterologists. Within a total of 16 statements, recommendations are made regarding diagnostic measures to screen for iron- and other anemia-related deficiencies regarding the triggers for medical intervention, treatment goals, and appropriate therapies. Anemia is a common cause of hospitalization, prevents physicians from discharging hospitalized patients, and is one of me most frequent comorbid conditions in patients with inflammatory bowel disease. It therefore needs appropriate attention and specific care. Copyright © 2007 Crohn's & Colitis Foundation of America, Inc.
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| 8. |
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| 9. |
- Heiervang, Einar, et al.
(författare)
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Psychiatric disorders in Norwegian 8- to 10-year-olds: an epidemiological survey of prevalence, risk factors, and service use.
- 2007
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Ingår i: Journal of the American Academy of Child and Adolescent Psychiatry. - : Elsevier BV. - 0890-8567 .- 1527-5418. ; 46:4, s. 438-447
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: The Bergen Child Study is a longitudinal study of child mental health from the city of Bergen, Norway. We present methods and results from the first wave of the study, focusing on prevalence of disorders, associations with risk factors, and the use of services. METHOD: The target population included all 9,430 children attending grades 2 to 4 in Bergen schools during the academic year 2002/2003. The main screening instrument was the Strengths and Difficulties Questionnaire, whereas diagnoses were based on the Development and Well-Being Assessment. Information about child and family risk factors and service use was also obtained in this second stage. RESULTS: In the first phase, the teacher Strengths and Difficulties Questionnaire was obtained for 9,155 (97%) of the target children and the matching parent Strengths and Difficulties Questionnaire for 6,297 (67%); 1,011 children (11%) were assessed with the Development and Well-Being Assessment in the second phase. The weighted prevalence for any DSM-IV psychiatric disorder was 7.0% (95% confidence interval 5.6%-8.5%). Disorders were associated with age, gender, learning difficulties, family type, and poverty. Although 75% of children with attention-deficit/hyperactivity disorder had been in contact with specialist mental health services, this was true for only 13% of those with pure emotional disorders. CONCLUSIONS: The overall prevalence of psychiatric disorders in children is relatively low in this Norwegian sample, when assessed with the Development and Well-Being Assessment. Children with emotional disorders have limited access to specialist services.
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| 10. |
- Saether, Stein Are, et al.
(författare)
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Inferring local adaptation from QST-FST comparisons : neutral genetic and quantitative trait variation in European populations of great snipe
- 2007
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Ingår i: Journal of Evolutionary Biology. - : Wiley. - 1010-061X .- 1420-9101. ; 20:4, s. 1563-1576
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Tidskriftsartikel (refereegranskat)abstract
- We applied a phenotypic QST (PST) vs. FST approach to study spatial variation in selection among great snipe (Gallinago media) populations in two regions of northern Europe. Morphological divergence between regions was high despite low differentiation in selectively neutral genetic markers, whereas populations within regions showed very little neutral divergence and trait differentiation. QST > FST was robust against altering assumptions about the additive genetic proportions of variance components. The homogenizing effect of gene flow (or a short time available for neutral divergence) has apparently been effectively counterbalanced by differential natural selection, although one trait showed some evidence of being under uniform stabilizing selection. Neutral markers can hence be misleading for identifying evolutionary significant units, and adopting the PST–FST approach might therefore be valuable when common garden experiments is not an option. We discuss the statistical difficulties of documenting uniform selection as opposed to divergent selection, and the need for estimating measurement error. Instead of only comparing overall QST and FST values, we advocate the use of partial matrix permutation tests to analyse pairwise QST differences among populations, while statistically controlling for neutral differentiation.
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