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排序方式: 共有7719条查询结果,搜索用时 31 毫秒
81.
Karen W Cullen Issa Zakeri Erin W Pryor Tom Baranowski Janice Baranowski Kathy Watson 《Health education & behavior》2004,31(2):258-269
The impact of goal attainment in a dietary change program to increase fruit, 100% juice, and vegetable consumption was assessed among fourth-grade students. At each session, the students were given goals related to increasing fruit, juice, and vegetable consumption. Baseline consumption and postconsumption were assessed with up to 4 days of computerized dietary recalls. Analyses included regression models predicting postconsumption from the numbers of fruit-juice goals, vegetable goals, or total number of general goals attained, respectively. For students with low baseline fruit-juice preferences, attaining more fruit-juice goals resulted in increased post-fruit-juice consumption. Among those with low baseline vegetable consumption, attaining one vegetable goal was related to higher post-vegetable consumption. For boys and those with high baseline fruit, juice, and vegetable consumption, attaining three general goals was related to increased fruit, juice, and vegetable intake. The results show that goal attainment was somewhat effective in promoting dietary change among children. 相似文献
82.
Rodríguez FJ Ceballos D Schüttler M Valero A Valderrama E Stieglitz T Navarro X 《Journal of neuroscience methods》2000,98(2):105-118
This paper describes a new tripolar spiral cuff electrode, composed of a thin (10 microm) and flexible polyimide insulating carrier and three circumneural platinum electrodes, suitable for stimulation of peripheral nerves. The cuffs were implanted around the sciatic nerve of two groups of ten rats each, one in which the polyimide ribbon was attached to a plastic connector to characterize the in vivo stimulating properties of the electrode, and one without a connector for testing possible mechanical nerve damage by means of functional and histological methods. The polyimide cuff electrodes induced only a very mild foreign body reaction and did not change the nerve shape over a 2-6 month implantation period. There were no changes in the motor and sensory nerve conduction tests, nociceptive responses and walking track pattern over follow-up, and no morphological evidence of axonal loss or demyelination, except in one case with partial demyelination of some large fibers after 6 months. By delivering single electrical pulses through the cuff electrodes graded recruitment curves of alpha-motor nerve fibers were obtained. Recruitment of all motor units was achieved with a mean charge density lower than 4 microC/cm(2) for a pulse width of 50 micros at the time of implantation as well as 45 days thereafter. These data indicate that the polyimide cuff electrode is a stable stimulating device, with physical properties and dimensions that avoid nerve compression or activity-induced axonal damage. 相似文献
83.
Melinda L Irwin Anne McTiernan Richard N Baumgartner Kathy B Baumgartner Leslie Bernstein Frank D Gilliland Rachel Ballard-Barbash 《Journal of clinical oncology》2005,23(4):774-782
PURPOSE: Obese women and women who gain weight after a breast cancer diagnosis are at a greater risk for breast cancer recurrence and death compared with lean women and women who do not gain weight after diagnosis. In this population-based study, we assessed weight and body fat changes from during the first year of diagnosis to during the third year after diagnosis, and whether any changes in weight and body fat varied by demographic, prognostic, and lifestyle factors in 514 women with incident Stage 0-IIIA breast cancer. METHODS: Patients were participants in the Health, Eating, Activity, and Lifestyle (HEAL) study. Weight and body fat (via dual-energy x-ray absorptiometry scans) were measured during the baseline visit and 2 years later at a follow-up visit. Analysis of covariance methods were used to obtain mean weight and body fat changes adjusted for potential cofounders. RESULTS: Women increased their weight and percent body fat by 1.7 +/- 4.7 kg and 2.1% +/- 3.9%, respectively, from during their first year of diagnosis to during their third year of diagnosis. A total of 68% and 74% of patients gained weight and body fat, respectively. Greater increases in weight were observed among women diagnosed with a higher disease stage, younger age, being postmenopausal, and women who decreased their physical activity from diagnosis to up to 3 years after diagnosis (P for trend < .05). CONCLUSION: Weight and body fat increased in the postdiagnosis period. Future research should focus on the effect of physical activity on weight and fat loss and breast cancer prognosis. 相似文献
84.
Dana E Rollison Kathy J Helzlsouer Neal A Halsey Keerti V Shah Raphael P Viscidi 《Cancer epidemiology, biomarkers & prevention》2005,14(6):1448-1452
Simian virus 40 (SV40) genome sequences have been detected in human non-Hodgkin lymphoma (NHL) tissues, and past infection with SV40 may be a risk factor for NHL. We conducted a population-based nested case-control study to investigate the association between serum antibodies to SV40 and incident NHL. Two research serum banks were established in Washington County, MD, with >45,000 volunteers contributing blood samples collected in 1974 and 1989. Incident cases of NHL diagnosed through 2002 (n = 170) were identified among participants by linkage to population-based cancer registries. Two controls were matched to each case (n = 340) on age, sex, and date of blood draw. Circulating immunoglobulin G antibodies to SV40 were measured using virus-like particle (VLP) ELISA. Positive samples were tested for cross-reactivity with JC virus (JCV) and BK virus (BKV) through competitive inhibition assays. Associations between SV40 antibody seropositivity and NHL were estimated using conditional logistic regression. Whereas SV40 antibodies were detected by VLP ELISA in 15% of cases and 10% of controls [matched odds ratio (OR), 1.97; 95% confidence interval (95% CI), 1.03-3.76], the SV40 reactivity of 85% of the SV40 antibody-positive sera was decreased by adsorption with BKV and/or JCV VLPs. Antibodies specific for SV40 (not cross-reactive) were identified in only 1.8% of cases and 1.6% of controls (OR, 1.51; 95% CI, 0.41-5.52). Our findings suggest that past infection with SV40 is not associated with an increased risk of developing NHL. 相似文献
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88.
D. Michal Freedman Kenneth P. Cantor Mary H. Ward Kathy J. Helzlsouer 《Archives of environmental & occupational health》2013,68(5):326-329
Nitrate in drinking water has been implicated as a possible risk factor for non-Hodgkin's lymphoma. The authors examined the association between non-Hodgkin's lymphoma and waterborne nitrate through a population-based case-control study of white men in Minnesota. The authors, by linking residential histories with community water records, estimated average long-term exposure to nitrate in drinking water from 1947 to 1975 for 73 cases diagnosed between 1980 and 1982 and for 147 controls who used community water supplies. No association was found between nitrate levels in community water supplies and non-Hodgkin's lymphoma within the range of study exposures (median of highest exposure category = 2.4 mg nitrate/l [range = 0.1-7.2 mg/l]). The findings provide some safety assurance for those who use water systems that have nitrate levels that are less than 2.4 mg/l. 相似文献
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