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Kristjánsson AL Sigfúsdóttir ID Allegrante JP Helgason AR 《American journal of health behavior》2009,33(1):69-79
OBJECTIVES: To examine the association between health behavior indicators, school contentment, and academic achievement. METHODS: Structural equation modeling with 5810 adolescents. RESULTS: Our model explained 36% of the variance in academic achievement and 24% in school contentment. BMI and sedentary lifestyle were negatively related to school contentment and academic achievement, but physical activity was positively related to school contentment and academic achievement (P < .01). School contentment was strongly related to academic achievement but only a weak mediator of the health behavior indicators. CONCLUSION: Findings may inform the efforts to improve academic achievement and the general health status of youth. 相似文献
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White Crested Polish (WCP) chickens are an interesting breed because of skull anatomy (crest), brain size and composition. This makes them attractive to investigate processes of selection that could parallel a step towards speciation in terms of ethological isolation. Lohmann Brown Classic (BL) and Red Leghorn (RL) were selected as comparative breeds to detect whether WCPs flock together as shown by shorter inter-individual distances within WCP than across breeds. WCP and BL were observed in the first year whereas RL served as comparative breed to WCP in the second year. Eggs of both breeds of each year were incubated at the same time, and chicks hatched and were raised together. Three young hens of each breed were randomly chosen and observed weekly in an open field situation for 20 min between the first and 31st week of life. Intra-breed distances differed significantly from those distances measured across breeds. Results demonstrate breed-specific flocking within observed breeds. This flocking behaviour may reflect breed-specific social and sexual preferences. Our observations indicate that domestic breeds may represent an ethological entity. Selective processes controlled by human intervention as given in domestication may therefore to be set in parallel to evolutionary processes. 相似文献
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Vicini FA Chen P Wallace M Mitchell C Hasan Y Grills I Kestin L Schell S Goldstein NS Kunzman J Gilbert S Martinez A 《International journal of radiation oncology, biology, physics》2007,69(4):1124-1130
PURPOSE: We present our ongoing clinical experience utilizing three-dimensional (3D)-conformal radiation therapy (3D-CRT) to deliver accelerated partial breast irradiation (APBI) in patients with early-stage breast cancer treated with breast-conserving therapy. METHODS AND MATERIALS: Ninety-one consecutive patients were treated with APBI using our previously reported 3D-CRT technique. The clinical target volume consisted of the lumpectomy cavity plus a 10- to 15 -mm margin. The prescribed dose was 34 or 38.5 Gy in 10 fractions given over 5 consecutive days. The median follow-up was 24 months. Twelve patients have been followed for > or =4 years, 20 for > or =3.5 years, 29 for >3.0 years, 33 for > or =2.5 years, and 46 for > or =2.0 years. RESULTS: No local recurrences developed. Cosmetic results were rated as good/excellent in 100% of evaluable patients at > or = 6 months (n = 47), 93% at 1 year (n = 43), 91% at 2 years (n = 21), and in 90% at > or =3 years (n = 10). Erythema, hyperpigmentation, breast edema, breast pain, telangiectasias, fibrosis, and fat necrosis were evaluated at 6, 24, and 36 months after treatment. All factors stabilized by 3 years posttreatment with grade I or II rates of 0%, 0%, 0%, 0%, 9%, 18%, and 9%, respectively. Only 2 patients (3%) developed grade III toxicity (breast pain), which resolved with time. CONCLUSIONS: Delivery of APBI with 3D-CRT resulted in minimal chronic (> or =6 months) toxicity to date with good/excellent cosmetic results. Additional follow-up is needed to assess the long-term efficacy of this form of APBI. 相似文献
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Buchmann I Riedmüller K Hoffner S Mack U Aulmann S Haberkorn U 《Cancer biotherapy & radiopharmaceuticals》2007,22(6):779-789
PURPOSE: Breast carcinomas express the Na(+)/I() symporter and may-albeit not a routine procedure-be imaged with (123)iodide ((123)I) and (99m)technetium-pertechnetate ((99m)TcO(4)(-)) scintigraphy. The aim of our prospective study was the comparison of (99m)TcO(4)(-)--and (123)I-single-photon emission computed tomography (SPECT) with (18)F-2-fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) in patients suspicious for breast cancer. METHODS: Twenty-nine (29) untreated patients suspected of having breast carcinoma were prospectively examined with thorax SPECT with (99m)TcO(4)(-) (n=19) or (123)I (n=10), respectively, and FDG-PET (n=29) prior to biopsy. Tumor-to-background ratios (TBRs) were calculated for SPECT findings. Mean and maximum standardized uptake values (SUVs) were calculated for PET findings. Findings were compared in an intra-individual lesion-to-lesion analysis. RESULTS: In 28 of 29 patients, malignancy was verified with histopathology. In imaging the primary tumor, sensitivities of (99m)TcO(4)(-)-SPECT, (123)I-SPECT, and FDG-PET were 63%, 67%, and 89%, respectively. TBR maximum was 2.6+/-1.1 in (99m)TcO(4)()-SPECT and 2.3+/-0.6 in (123)I-SPECT. In FDG-PET, mean tumor SUV was 4.1+/-4 and maximum tumor SUV was 5.4+/-5.1. In contrast to FDG-PET, (99m)TcO(4)()-SPECT was ineffective in imaging nodal and distant metastases in the thorax, and (123)I-SPECT failed in imaging lymph node infiltrations. Distant metastases were not present in patients of the (123)I group, and the value of (123)I-SPECT was not evaluated. CONCLUSIONS: In contrast to FDG-PET, (99m)TcO(4)(-) and (123)I-SPECT are ineffective in imaging breast carcinoma in clinical practice. 相似文献
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Maetzler W Reimold M Liepelt I Solbach C Leyhe T Schweitzer K Eschweiler GW Mittelbronn M Gaenslen A Uebele M Reischl G Gasser T Machulla HJ Bares R Berg D 《NeuroImage》2008,39(3):1027-1033
[(11)C]PIB ((11)C-6-OH benzothiazole) reflects the regional distribution of amyloid (beta-sheeted proteins) in patients with Alzheimer's disease (AD). Proteinaceous inclusions in Parkinson's disease with dementia (PDD), so-called Lewy bodies, also consist of fibrillar, misfolded proteins, chiefly alpha-synuclein. To test whether PDD subjects show specific amyloid binding in vivo and whether this could reflect fibrillar alpha-synuclein accumulation, we investigated 10 PDD subjects with [(11)C]PIB-PET. Radioligand binding was compared to that in 11 control and 6 AD subjects. Furthermore, postmortem sections of 4 patients with Parkinson's disease (PD), therefrom 2 with dementia (PDD), and of 6 controls were stained with PIB to evaluate the histological distribution of the fluorescent ligand in the brainstem. In PET, only 2 PDD patients displayed increased PIB binding to cortical amyloid comparable to AD patients. The other 8 patients showed control-like cortical findings but elevated PIB binding in the pons and mesencephalon. Fluorescence microscopy showed PIB binding to Lewy bodies and neuromelanin in the substantia nigra of PD and PDD brainstem sections, but not in controls. These data suggest that PIB-PET can be used to further differentiate PDD with respect to cortical amyloid. Furthermore, we provide evidence that--in addition to nonspecific binding--PIB uptake in the brainstem may also reflect PDD related amyloid. 相似文献