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51.
K M Linnet K Wisborg E Agerbo N J Secher P H Thomsen T B Henriksen 《Archives of disease in childhood》2006,91(8):655-660
AIMS: To study the association between gestational age and birth weight and the risk of clinically verified hyperkinetic disorder. METHODS: Nested case-control study of 834 cases and 20 100 controls with incidence density sampling. RESULTS: Compared with children born at term, children born with gestational ages of 34-36 completed weeks had a 70% increased risk of hyperkinetic disorder (rate ratio (RR) 1.7, 95% confidence interval (CI) 1.2 to 2.5). Children with gestational ages below 34 completed weeks had an almost threefold increased risk (RR 2.7, 95% CI 1.8 to 4.1). Children born at term with birth weights of 1500-2499 g had a 90% increased risk of hyperkinetic disorder (RR 1.9, 95% CI 1.2 to 2.9), and children with birth weights of 2500-2999 g had a 50% increased risk (RR 1.5, 95% CI 1.2 to 1.8) compared with children born at term with birth weights above 2999 g. The results were adjusted for socioeconomic status of the parents, family history of psychiatric disorders, conduct disorders, comorbidity, and maternal smoking during pregnancy. Results related to birth weight were unchanged after adjusting for differences in gestational age. CONCLUSIONS: Children born preterm, also close to term, and children born at term with low birth weights (1500-2499 g) have an increased risk of clinically verified hyperkinetic disorder. These findings have important public health perspectives because the majority of preterm babies are born close to term. 相似文献
52.
Lise Borgwardt Liselotte H?jgaard Henrik Carstensen Henning Laursen Markus Nowak Carsten Thomsen Kjeld Schmiegelow 《Journal of clinical oncology》2005,23(13):3030-3037
PURPOSE Positron emission tomography (PET) has been used in grading of CNS tumors in adults, whereas studies of children have been limited. PATIENTS AND METHODS Nineteen boys and 19 girls (median age, 8 years) with primary CNS tumors were studied prospectively by fluorine-18 2-fluoro-2-deoxy-D-glucose (FDG) PET with (n = 16) or without (n = 22) H(2)(15)O-PET before therapy. Image processing included coregistration to magnetic resonance imaging (MRI) in all patients. The FDG uptake in tumors was semiquantitatively calculated by a region-of-interest-based tumor hotspot/brain index. Eight tumors without histologic confirmation were classified as WHO grade 1 based on location, MRI, and clinical course (22 to 42 months). Results Four grade 4 tumors had a mean index of 4.27 +/- 0.5, four grade 3 tumors had a mean index of 2.47 +/- 1.07, 10 grade 2 tumors had a mean index of 1.34 +/- 0.73, and eight of 12 grade 1 tumors had a mean index of -0.31 +/- 0.59. Eight patients with no histologic confirmation had a mean index of 1.04. For these 34 tumors, FDG uptake was positively correlated with malignancy grading (n = 34; r = 0.72; P < .01), as for the 26 histologically classified tumors (n = 26; r = 0.89; P < .01). The choroid plexus papilloma (n = 1) and the pilocytic astrocytomas (n = 3) had a mean index of 3.26 (n = 38; r = 0.57; P < .01). H(2)(15)O-uptake showed no correlation with malignancy. Digitally performed PET/MRI coregistration increased information on tumor characterization in 90% of cases. CONCLUSION FDG PET of the brain with MRI coregistration can be used to obtain a more specific diagnosis with respect to malignancy grading. Improved PET/MRI imaging of the benign hypermetabolic tumors is needed to optimize clinical use. 相似文献
53.
Grace Wang Charles L Vogel Susan G Hilsenbeck Walter Voigt Sharon Thomsen 《Breast cancer research and treatment》1984,4(4):283-288
Summary Using sucrose gradient centrifugation, human breast cancer estrogen receptors appear in two molecular forms sedimenting at either 8S or 4S fractions. The sum of these two fractions has been valuable clinically in helping to predict response to hormonal therapies. It has been suggested that the 4S receptor may not be of predictive value and that the practice of using only dextran-coated charcoal methodology might thus overestimate the number of patients whose tumors might be hormonally dependent. The present study correlates clinical response to hormonal manipulations with 8S and 4S receptors as determined by sucrose density gradient centrifugation. Patients with only 4S positive receptors had a 56% response rate to hormonal manipulation compared with a 52% response rate in patients with positive 8S alone or with both 8S and 4S receptors. Although patient numbers are small in this and the other three published series addressing this question, our data do not confirm two previously published studies suggesting clinical importance of 8S/4S fractionation. 相似文献
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