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61.
We performed two case–control studies on brain tumours diagnosed during 1 January 1997 to 30 June 2000 and 1 July 2000 to 31 December 2003, respectively. Living cases and controls aged 20–80 years were included. An additional study was performed on deceased cases with a malignant brain tumour using deceased controls. Pooled results for glioma yielded for ipsilateral use of mobile phone odds ratio (OR) = 2.9, 95% confidence interval (CI) = 1.8–4.7 in the >10 years latency group. The corresponding result for cordless phone was OR = 3.8, 95% CI = 1.8–8.1. OR increased statistically significant for cumulative use of wireless phones per 100 h and per year of latency. For high-grade glioma ipsilateral use of mobile phone gave OR = 3.9, 95% CI = 2.3–6.6 and cordless phone OR = 5.5, 95% CI = 2.3–13 in the >10 years latency group. Heredity for brain tumour gave OR = 3.4, 95% CI = 2.1–5.5 for glioma. There was no interaction with use of wireless phones. X-ray investigation of the head gave overall OR = 1.3, 95% CI = 1.1–1.7 for glioma without interaction with use of wireless phones or heredity. In conclusion use of mobile and cordless phone increased the risk for glioma with highest OR for ipsilateral use, latency >10 years and third tertile of cumulative use in hours. In total, the risk was highest in the age group <20 years for first use of a wireless phone. 相似文献
62.
63.
Techniques for Eliciting Human Intelligence: Examining Possible Order Effects of the Scharff Tactics
The present study examines non-coercive interview techniques aimed for eliciting intelligence from human sources. Two versions of the Scharff technique were compared against the direct approach (a combination of open-ended and specific questions). The Scharff conditions were conceptualised into four tactics and differed with respect to when the confirmation tactic was implemented: before or after an initial open-ended question. Participants (n = 93) took the role of a source in a phone interview and were instructed to strike a balance between not revealing too little or too much information. In general, the Scharff technique outperformed the direct approach on all important measures. The sources in the Scharff conditions revealed more new information, and found it more difficult to understand the interviewer's information objectives. Importantly, the sources interviewed by the Scharff technique underestimated how much new information they revealed, whereas the sources interviewed by the direct approach overestimated the amount of new information revealed. Although no clear order effects of the Scharff tactics were found, we introduce an alternative method for implementing the confirmation tactic. 相似文献
64.
Suman Kundu Lennart C Karssen A Cecile JW Janssens 《European journal of human genetics : EJHG》2012,20(12):1270-1274
Various modeling methods have been proposed to estimate the potential predictive ability of polygenic risk variants that predispose to various common diseases. However, it is unknown whether differences between them affect their conclusions on predictive ability. We reviewed input parameters, assumptions and output of the five most common methods and compared their estimates of the area under the receiver operating characteristic (ROC) curve (AUC) using hypothetical data representing effect sizes and frequencies of genetic variants, population disease risk and number of variants. To assess the accuracy of the estimated AUCs, we aimed to reproduce the AUCs of published empirical studies. All methods assumed that the combined effect of genetic variants on disease risk followed a multiplicative risk model of independent genetic effects, but they either assumed per allele, per genotype or dominant/recessive effects for the genetic variants. Modeling strategy and input parameters differed. Methods used simulation analysis or analytical formulas with effect sizes quantified by odds ratios (ORs) or relative risks. Estimated AUC values were similar for lower ORs (<1.2). When AUCs were larger (>0.7) due to variants with strong effects, differences in estimated AUCs between methods increased. The simulation methods accurately reproduced the AUC values of empirical studies, but the analytical methods did not. We conclude that despite differences in input parameters, the modeling methods estimate similar AUC for realistic values of the ORs. When one or more variants have stronger effects and AUC values are higher, the simulation methods tend to be more accurate. 相似文献
65.
Anders Gülfe Tore Saxne Lennart T. H. Jacobsson Ingemar F. Petersson Pierre Geborek 《Arthritis care & research》2010,62(10):1399-1406
Objective
To introduce a novel, simple, utility‐based outcome measure, the number needed per quality‐adjusted life year (QALY) gained (NNQ), and to apply it in clinical practice in anti–tumor necrosis factor (anti‐TNF)–treated patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and spondylarthritis (SpA).Methods
The NNQ is the number of patients one has to treat in order to gain 1 QALY. It is calculated as the inverted value of the utility gain (area under the curve) over 1 year in a cohort subjected to an intervention. EuroQol Index utility data from the South Swedish Arthritis Treatment register were used.Results
Patients with RA (n = 1,001), PsA (n = 241), and SpA (n = 255) were eligible for the study. First, second, and third treatment courses were studied. For RA, NNQ was 4.5, 6.4, and 5.2 for first, second, and third courses, respectively. For PsA and SpA, NNQ was 4.2–4.5, irrespective of treatment order. Treatment groups with <50 patients were not analyzed. During the study period 2002–2007, there were no secular trends of utility gains.Conclusion
The NNQ is an easily derived and understandable utility‐based outcome measure that may be useful for stakeholders and decision makers as well as for clinicians. It was readily applied in this study of TNF blockade across 3 arthritis diagnoses. NNQ varied little over diagnoses and treatment course order, with a possible exception in second treatment course in RA. 相似文献66.
67.
68.
Surgery for fulminating colitis during pregnancy 总被引:2,自引:1,他引:2
Dr. Måns G. Bohe M.D. Göran R. Ekelund M.D. Dr. Sven N. Genell M.D. Gerhard M. Gennser M.D. Hasse A. Jiborn M.D. Lennart J. Leandoer M.D. Claes G. Lindström M.D. Lars K. Svanberg M.D. 《Diseases of the colon and rectum》1983,26(2):119-122
Two cases of fulminating colitis presenting during pregnancy are described. In both cases, resectional surgery was performed. In the first case, cesarean section was combined with subtotal colectomy and ileostomy during the 32nd week of gestation. In the second case, cesarean section was performed during the 33rd week of gestation and proctocolectomy in the puerperium. In both cases, histopathologic examination showed colitis more consistent with Crohn's disease. It is concluded that if fulminating colitis appears during pregnancy it should be treated in the same manner as in the nonpregnant state. 相似文献
69.
Trausti Valdimarsson MD Lennart Franzen MD PhD Ewa Grodzinsky PhD Thomas Skogh MD PhD Magnus Ström MD PhD 《Digestive diseases and sciences》1996,41(1):83-87
The comparative diagnostic value of IgA anti-endomysium and IgA antigliadin antibodies in adults with histologically confirmed celiac disease is reported. Sera from 144 adult patients (without concurrent dermatitis herpetiformis or IgA deficiency) who underwent small bowel biopsy were analyzed for both IgA anti-endomysium and IgA anti-gliadin antibodies. Nineteen patients (13%) had celiac disease. The presence of IgA antiendomysium antibodies had a sensitivity of 74% and a specificity of 100%. The positive and negative predictive values were 100% and 96%, respectively, and the diagnostic accuracy was 97%. In contrast, IgA anti-gliadin antibodies had positive and negative predictive values of 28% and 96%, respectively, with a diagnostic accuracy of 71%. Based on these data, we suggest that small bowel biopsy is not necessary to diagnose celiac disease in symptomatic adults with IgA antiendomysium antibodies. Due to a negative predictive value of 96%, some symptomatic adults lacking anti-endomysium antibodies will not be correctly diagnosed without small bowel biopsy. 相似文献
70.
β-Chemokines and neutralizing antibody titers correlate with sterilizing immunity generated in HIV-1 vaccinated macaques 下载免费PDF全文
Jonathan L. Heeney Vera J. P. Teeuwsen Marille van Gils Willy M. J. M. Bogers Carlo De Giuli Morghen Antonia Radaelli Susan Barnett Bror Morein Lennart kerblom Yufei Wang Thomas Lehner David Davis 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(18):10803-10808
One of the obstacles to AIDS vaccine development is the variability of HIV-1 within individuals and within infected populations, enabling viral escape from highly specific vaccine induced immune responses. An understanding of the different immune mechanisms capable of inhibiting HIV infection may be of benefit in the eventual design of vaccines effective against HIV-1 variants. To study this we first compared the immune responses induced in Rhesus monkeys by using two different immunization strategies based on the same vaccine strain of HIV-1. We then utilized a chimeric simian/HIV that expressed the envelope of a dual tropic HIV-1 escape variant isolated from a later time point from the same patient from which the vaccine strain was isolated. Upon challenge, one vaccine group was completely protected from infection, whereas all of the other vaccinees and controls became infected. Protected macaques developed highest titers of heterologous neutralizing antibodies, and consistently elevated HIV-1-specific T helper responses. Furthermore, only protected animals had markedly increased concentrations of RANTES, macrophage inflammatory proteins 1α and 1β produced by circulating CD8+ T cells. These results suggest that vaccine strategies that induce multiple effector mechanisms in concert with β-chemokines may be desired in the generation of protective immune responses by HIV-1 vaccines. 相似文献