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OBJECTIVE: To examine whether neighborhood-level socioeconomic status is an independent risk factor for health risk behaviors. METHODS: Data from the Third National Health and Nutrition Examination Survey were linked with census tracts from the 1990 US Census. Outcome variables included biomarkers for smoking and high dietary fat intake, and self-reported excessive alcohol consumption and physical inactivity. RESULTS: Multivariate logistic regression showed an association between high levels of neighborhood deprivation and increased odds of health risk behaviors independent of sociodemographic factors, BMI, and comorbidities. CONCLUSION: Living in highly deprived neighborhoods is associated with risky health behaviors.  相似文献   
74.
Aim: We have designed a study with the objective of describing the clinical impact of other viruses different from the respiratory syncytial virus (RSV) in hospitalized infants with bronchiolitis. Methods: A 3 year prospective study was conducted on infants admitted to the Paediatrics Department of the Severo Ochoa Hospital (Spain). We studied the frequency of 16 respiratory viruses. Clinical characteristics of RSV‐only infections were compared with other single agent viral infections. Results: Positive results were confirmed in 275 (86.5%) of the 318 children studied. A single virus was detected in 196 patients and 79 were dual or multiple viral infections. RSV was detected in 61.3% of total bronchiolitis. Rhinovirus (RV) was 17.4% of the identified virus, followed by human bocavirus (HBoV), adenovirus and metapneumovirus (hMPV). Only RV, HBoV and hMPV were significant as single infections. RSV patients were younger than HBoV (p > 0.0001) and hMPV (p = 0.025). Seasonality was clearly different between them. Children with RSV infection needed treatment in the intensive care unit more frequently than others. Conclusions: In hospitalized infants, RSV was the most frequent agent in bronchiolitis in winter, but other viruses were present in 47% of the patients. RV, HBoV and hMPV had a significant proportion of single infections. Clinical characteristics were similar amongst them, but seasonality was clearly different.  相似文献   
75.
Isthmic spondylolysis of the lumbar spine: MR imaging at 1.5 T   总被引:4,自引:0,他引:4  
The appearance on magnetic resonance (MR) images of the normal pars interarticularis in 13 patients was reviewed and contrasted with that of the pars in eight patients with spondylolysis. The pars defect usually had an intermediate signal intensity with all pulse sequences; however, this intensity was somewhat variable depending on the exact ratio of cartilage, fat, and fluid within each bone defect. The pars defect was best seen with spin-echo 600/20 (repetition time msec/echo time msec) images. In three cases, out-of-phase images showed the spondylolysis best, because of extension of fat to the borders of the defect. The sagittal view allowed one to separate spondylolysis from the joint space of posterior facets since the orientation of the defects is perpendicular to the facets; thus, a common pitfall encountered with cross-sectional axial imaging techniques is avoided. MR imaging poorly delineated bone fragments around the defect, which may produce nerve root impingement, but revealed other numerous complications that occur with spondylolysis, including spondylolisthesis and herniation of the disk above.  相似文献   
76.
We infused 11 mmol/kg of intravenous ethanol into dogs with either intact renal function (n = 5) or ureteral ligation (n = 7), and studied by frequent blood sampling and by urine collection the time and mode of ethanol equilibration, the elimination parameters, and the comparison of observed equilibrated plasma ethanol levels to levels predicted either by linear or by nonlinear kinetics. Equilibration time was 25 min or less, renal fraction of elimination was less than 5% of total elimination, and both linear (elimination rate) and nonlinear (Vmax and Km) elimination parameters were not different between dogs with intact renal function and dogs with anuria. Serum sodium concentration did not change throughout the experiments, eliminating the hypothesis that acute ethanol load creates clinically significant temporary osmotic water transfer from the intracellular into the extracellular compartment. Distribution volumes of ethanol from linear kinetics were slightly, but not statistically, greater than volumes from nonlinear kinetics. Equilibrated plasma ethanol levels predicted by linear kinetics agreed closely with observed levels greater than 4 mmol/liter, but underestimated observed levels less than 4 mmol/liter. Equilibrated plasma ethanol levels predicted by nonlinear kinetics agreed with observed levels throughout the range of observed concentrations. The use of linear kinetics to predict blood ethanol levels should be limited to the pseudolinear portion of the blood alcohol curve.  相似文献   
77.
Transabdominal versus endovaginal pelvic sonography: prospective study   总被引:1,自引:0,他引:1  
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography.  相似文献   
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79.
从平贝母茎叶中分离的平贝啶甙的结构   总被引:2,自引:0,他引:2  
本文报道自平贝母(Fritillaria ussuriensis Maxim)的地上茎叶中分得一种新的甾体生物碱甙,定名为平贝啶甙(pingbeidinoside),mp 242~243.2℃[a]D25+6.9°(c 0.145,MeOH)。经IR,MS,1HNMR和13CNMR谱解析,推定其结构为3β,16α,20-三羟基-Δ5-22,26-缩亚胺胆甾烷-25-O-α-D-葡萄糖甙。  相似文献   
80.
Cyano and amidino flavans, isoflavans and 3(2H)-isoflavenes were synthesized in order to study their in vitro antirhino-virus activity, by comparison with the known corresponding chloro derivatives. The activity of the new compounds was evaluated on rhinovirus 1 B infected HeLa cell cultures by examining their ability to interfere with viral cytopathic effect and with plaque formation. It was found that generally the cyano derivatives behave like the chloro compounds, whereas the amidino derivatives show a lower activity, although always dependent on the position of substituent.  相似文献   
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