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131.
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Bronchopulmonary dysplasia: radiographic appearance in middle childhood   总被引:1,自引:0,他引:1  
Chest radiographs were compared for three groups of children 8-9 years old: 23 survivors of bronchopulmonary dysplasia (BPD), 33 survivors of hyaline membrane disease without BPD, and 35 survivors of premature birth without neonatal respiratory problems. Only four children in the second group and three in the third had abnormal lungs. Linear shadows, apparently representing strands of fibrosis or deep pleural fissuring, were seen more frequently (15 of 23) in the BPD group than in the others (P less than .0001). Seventeen children in the BPD group had definite pulmonary abnormalities, none of them severe. The anteroposterior dimension of the chest in survivors of BPD tended to be decreased (P less than .001 vs that of reported control subjects).  相似文献   
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Success of HIV prevention projects for injection drug users (IDUs) depends on the support of the communities in which they are implemented. This article presents data from cross-sectional community surveys of HIV knowledge and attitudes toward peer-based HIV prevention interventions for injection drug users in a border area of Lang Son Province, Vietnam and Ning Ming County, Guangxi Province, China. Analysis of these surveys at baseline and 18 months reveals generally high or improving levels of HIV knowledge and positive attitudes toward the interventions in both Vietnam and China. Levels of knowledge and positive attitudes tended to be higher in Vietnam than in China. Interviews with staff and peer educators suggest that the project’s community education efforts have increased support for the interventions and contributed to their smooth implementation. However, the community surveys also reveal some continuing deficits in HIV knowledge and understanding of the interventions, including perceptions that provision of new needles/syringes will result in increased drug use. Additional education, including dissemination of countervailing project data, is necessary to address these deficits and further increase community support for the interventions.  相似文献   
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Background

Return visits to the emergency department (RTED) contribute to overcrowding and may be a quality of care indicator. Previous studies focused on factors predicting returns to and from the same center. Little is known about RTEDs across a range of community and specialty hospitals within a large geographic area.

Objective

We sought to measure the frequency of pediatric RTEDs and describe their directional pattern across centers in a large catchment area.

Methods

We conducted a multicenter, retrospective cross-sectional study of pediatric emergency visits in the Vancouver lower mainland within 1 year. Visits were linked across study sites, including one pediatric quaternary care referral center and 17 sites ranging from large regional centers to smaller community emergency departments (EDs). Returns were defined as subsequent visits to any site with a compatible diagnosis within 7 days of an index visit.

Results

Among a total of 139,278 index ED visits by children, 12,133 (8.7% [95% confidence interval 8.6–8.9%]) were associated with 14,645 return visits to an ED. Three quarters of all index visits occurred at a general ED center, of which 8.9% had at least one RTED and 22% of these returns occurred at the pediatric ED (PED). Among PED index visits, 8.2% had at least one RTED and 13.6% of these returned to a general center. Overall, 38.9% of all RTEDs occurred at the PED. Multivariate regression did not identify any statistically significant association between ED crowding measures and likelihood of RTEDs.

Conclusions

Compared to single-center studies, this study linking hospitals within a large geographic area identified a higher proportion of RTEDs with a disproportionate burden on the PED.  相似文献   
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Antioxidant and UV absorption activities of three aaptamine derivatives including piperidine[3,2-b]demethyl(oxy)aaptamine (C1), 9-amino-2-ethoxy-8-methoxy-3H-benzo[de][1,6]naphthyridine-3-one (C2), and 2-(sec-butyl)-7,8-dimethoxybenzo[de]imidazo[4,5,1-ij][1,6]-naphthyridin-10(9H)-one (C3) were theoretically studied by density functional theory (DFT). Direct antioxidant activities of C1–C3 were firstly evaluated via their intrinsic thermochemical properties and the radical scavenging activity of the potential antioxidants with the HOO˙/HO˙ radicals via four mechanisms, including: hydrogen atom transfer (HAT), single electron transfer (SET), proton loss (PL) and radical adduct formation (RAF). Kinetic calculation reveals that HOO˙ scavenging in water occurs via HAT mechanism with C1 (kapp, 7.13 × 106 M−1 s−1) while RAF is more dominant with C2 (kapp, 1.40 × 105 M−1 s−1) and C3 (kapp, 2.90 × 105 M−1 s−1). Antioxidant activity of aaptamine derivatives can be classified as C1 > C3 > C2. Indirect antioxidant properties based on Cu(i) and Cu(ii) ions chelating activity were also investigated in aqueous phase. All three studied compounds show spontaneous and favorable Cu(i) ion chelating activity with ΔG0 being −15.4, −13.7, and −15.7 kcal mol−1, whereas ΔG0 for Cu(ii) chelation are −10.4, −10.8, and −2.2 kcal mol−1 for C1, C2 and C3, respectively. In addition, all compounds show UVA and UVB absorption; in which the excitations are determined mostly as π–π* transition. Overall, the results suggest the potential applications of the aaptamines in pharmaceutics and cosmetics, i.e. as a sunscreen and antioxidant ingredient.

Antioxidant and UV absorption activities of three aaptamine derivatives were theoretically studied by density functional theory (DFT) and time-dependent density functional theory (TD-DFT).  相似文献   
140.
Alpinia Roxb. is the largest genus of the Zingiberaceae family. A large number of Alpinia species has been used as food and traditional medicines. Alpinia essential oils have been studied for their chemical profiles, in which 1,8-cineole, β-pinene, α-pinene, β-myrcene, camphor, γ-terpinene, p-cymene, geraniol, α-fenchyl acetate, ocimene, methyl cinnamate, and β-caryophyllene have been found to be the major compounds. Essential oils isolated from Alpinia plants have been reported to have antimicrobial, cytotoxic, antioxidant, anti-inflammatory, anti-asthmatic, tyrosinase inhibitory, insecticidal, and larvicidal activities and slimming aromatherapy. In this review, the comprehensive information regarding the volatile components of various Alpinia plants, the bioactivities of Alpinia essential oils and their major compounds are provided.

Alpinia Roxb. is the largest genus of the Zingiberaceae family.  相似文献   
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