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561.
Objectives:  We explored the association between socioeconomic position and four different aspects of adolescent health behavior in a wide range of European countries, the US, Canada and Israel. Methods:  Data were collected from the Health Behaviour in School-aged Children (HBSC) study in 2002. Representative samples of 13 and 15 year olds completed a standardised questionnaire during school hours in each country. Logistic regression analyses were used to investigate the independent effect of parental occupation and family affluence on tobacco and alcohol use, vegetable consumption and TV viewing. Results:  Family affluence showed no significant association with regular smoking in most countries, whereas an increase in smoking with decreasing occupational status was found in half of the countries. For alcohol consumption a positive association was found with family affluence in half of the countries, while no relationship with parental occupation was observed. Both measures of socioeconomic position were strong independent predictors for vegetable consumption and television viewing in almost all countries. Conclusions:  The findings suggest that health behaviours that begin to develop in adolescence are less strongly influenced by parental socioeconomic position. Preventive intervention strategies should take the different socioeconomic patterns of health behaviour into account. Submitted: 20 February 2008; revised: 11 October 2008; accepted: 20 October 2008  相似文献   
562.

Objective:  

To examine trends in the prevalence of monthly alcohol use and lifetime drunkenness among 15 year olds in 20 European countries, the Russian Federation, Israel, the United States of America, and Canada.  相似文献   
563.
564.
The adult central nervous system (CNS) contains adult neural stem/progenitor cells (NSPCs) that possess the ability to differentiate into the primary cell types found in the CNS and to regenerate lost or damaged tissue. The ability to specifically and spatially control differentiation is vital to enable cell-based CNS regenerative strategies. Here we describe the development of a protein-biomaterial system that allows rapid, stable and homogenous linking of a growth factor to a photocrosslinkable material. A bioactive recombinant fusion protein incorporating pro-neural rat interferon-γ (rIFN-γ) and the AviTag for biotinylation was successfully expressed in Escherichia coli and purified. The photocrosslinkable biopolymer, methacrylamide chitosan (MAC), was thiolated, allowing conjugation of maleimide-strepatavidin via Michael-type addition. We demonstrated that biotin-rIFN-γ binds specifically to MAC-streptavidin in stoichiometric yields at 100 and 200 ng/mL in photocrosslinked hydrogels. For cell studies, NSPCs were photo-encapsulated in 100 ng/mL biotin-rIFN-γ immobilized MAC based scaffolds and compared to similar NSPC-seeded scaffolds combining 100 ng/mL soluble biotin-rIFN-γ vs. no growth factor. Cells were cultured for 8 days after which differentiation was assayed using immunohistochemistry for lineage specific markers. Quantification showed that immobilized biotin-rIFN-γ promoted neuronal differentiation (72.8 ± 16.0%) similar to soluble biotin-rIFN-γ (71.8 ± 13.2%). The percentage of nestin-positive (stem/progenitor) cells as well as RIP-positive (oligodendrocyte) cells were significantly higher in scaffolds with soluble vs. immobilized biotin-rIFN-γ suggesting that 3-D immobilization results in a more committed lineage specification.  相似文献   
565.
566.

Background

Low-molecular-weight heparins (LMWH) are the most commonly used anticoagulant during pregnancy for prevention or treatment of VTE. However, the size of the associated risk of postpartum haemorrhage (PPH) is unknown.

Objective

To assess the bleeding risk of high dose LMWH, also in relation to time between last dose LMWH and delivery.

Material and methods

From 1999 to 2009, we followed 88 pregnant women who were started on therapeutic anticoagulation. Controls were pregnant women without LMWH, matched 1:4 for parity, mode of delivery, age, gestational age and delivery date. PPH was defined as > 500 ml blood loss for vaginal delivery (severe PPH in vaginal delivery as > 1000 ml) and > 1000 ml for cesarean section (CS). Women were divided into subgroups by the interval between last dose of anticoagulation and delivery (< 12, 12-24 hrs, > 24 hrs).

Results

Risk of PPH after vaginal delivery was 30% and 18% for LMWH-users and non-users, respectively (OR 1.9, 95%CI 1.1-3.5). Risk of severe PPH after vaginal delivery was not different (5.6 vs 5.0%; OR 1.1; 0.4-3.6). Risk of PPH after CS was 12% in LMWH-users and 4% in non-users (OR 2.9; 0.5-19.4). Both events of LMWH-users occurred after emergency CS. The risk of PPH associated with delivery within 24 hours after last dose of LMWH was 1.2 fold higher (95%CI 0.4-3.6) compared to a larger interval.

Conclusion

High dose LMWH carries an increased risk of more than 500 mL blood loss after vaginal delivery. However, this results not in more clinical relevant severe PPHs. The interval between last dose of LMWH and delivery does not influence the risk of PPH.  相似文献   
567.
In animal models, the secretion of the cardiac hormone, brain natriuretic peptide (BNP), and its closely related peptide, atrial natriuretic peptide (ANP), are stimulated by acute hypoxia. There is extensive human evidence for a rise in ANP under acute hypoxic conditions but very little evidence regarding the BNP response to acute hypoxia in humans. We therefore subjected seven healthy subjects to an acute hypobaric hypoxic stimulus to examine if BNP secretion increases rapidly. Significant hypoxaemia (mean nadir oxygen saturation 62.3%) was induced but no significant rise in BNP occurred. This suggests that either such acute hypoxaemia is well tolerated by the healthy human heart or it is not a stimulus for BNP secretion.  相似文献   
568.
This study examined relationships between music preferences and substance use (tobacco, alcohol, cannabis) among 18,103 fifteen-year-olds from 10 European countries. In 2005-2006, across Europe, preferences for mainstream Pop (pop chart music) and Highbrow (classical music and jazz) were negatively associated with substance use, while preferences for Dance (house/trance and techno/hardhouse) were associated positively with substance use. In three countries, links were identified between liking Rock (rock, heavy metal punk/hardcore, and gothic) and substance use; associations between Urban (hip-hop and R&B) and substance use were mixed. No substantial gender differences emerged in these patterns, and controlling for relevant covariates did not attenuate the predictive value of substance use. The findings are consistent with the conclusion that music is a robust marker of adolescent substance use.  相似文献   
569.
BACKGROUND: Exposure to violence predisposes youths to future violent behavior. Breaking the cycle of violence in inner cities is the primary objective of hospital-based violence intervention and prevention programs. An evaluation was undertaken to determine if a hospital-based, peer intervention program, "Caught in the Crossfire," reduces the risk of criminal justice involvement, decreases hospitalizations from traumatic reinjury, diminishes death from intentional violent trauma, and is cost effective. STUDY DESIGN: We designed a retrospective cohort study conducted between January 1998 and June 2003 at a university-based urban trauma center. The duration of followup was 18 months. Patients were 12 to 20 years of age and were hospitalized for intentional violent trauma. The "enrolled" group had a minimum of five interactions with an intervention specialist. The control group was selected from the hospital database by matching age, gender, race or ethnicity, type of injury, and year of admission. All patients came from socioeconomically disadvantaged areas. RESULTS: The total sample size was 154 patients. Participation in the hospital-based peer intervention program lowered the risk of criminal justice involvement (relative risk=0.67; 95% CI, 0.45, 0.99; p=0.04). There was no effect on risks of reinjury and death. Subsequent violent criminal behavior was reduced by 7% (p=0.15). Logistic regression analysis showed age had a confounding effect on the association between program participation and criminal justice involvement (relative risk=0.71; p=0.043). When compared with juvenile detention center costs, the total cost reduction derived from the intervention program annually was $750,000 to $1.5 million. CONCLUSIONS: This hospital-based peer intervention program reduces the risk of criminal justice system involvement, is more effective with younger patients, and is cost effective. Any effect on reinjury and death will require a larger sample size and longer followup.  相似文献   
570.
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