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In recent years, many states and localities in the USA have enacted bicycle helmet laws. We estimate the effects of these laws on injuries requiring emergency department treatment. Using hospital‐level panel data and triple difference models, we find helmet laws are associated with reductions in bicycle‐related head injuries among children. However, laws also are associated with decreases in non‐head cycling injuries, as well as increases in head injuries from other wheeled sports. Thus, the observed reduction in bicycle‐related head injuries may be due to reductions in bicycle riding induced by the laws. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Background

Little is known about depression in older people in sub-Saharan Africa, the associated impact of HIV, and the influence on health perceptions.

Objectives

Examine the prevalence and correlates of depression; explore the relationship between depression and health perceptions in HIV-infected and -affected older people.

Methods

In 2010, 422 HIV-infected and -affected participants aged 50+ were recruited into a cross-sectional study. Nurse professionals interviewed participants and a diagnosis of depressive episode was derived from the Composite International Diagnostic Interview (Depression module) using the International Classification of Diseases diagnostic criteria and categorised as major (MDE) or brief (BDE).

Results

Overall, 42.4% (n=179) had a depressive episode (MDE: 22.7%, n=96; BDE: 19.7%, n=83). Prevalence of MDE was significantly higher in HIV-affected (30.1%, 95% CI 24.0–36.2%) than HIV-infected (14.8%, 95% CI 9.9–19.7%) participants; BDE was higher in HIV-infected (24.6%, 95% CI 18.7–30.6%) than in HIV-affected (15.1%, 95% CI 10.3–19.8%) participants. Being female (aOR 3.04, 95% CI 1.73–5.36), receiving a government grant (aOR 0.34, 95% CI 0.15–0.75), urban residency (aOR 1.86, 95% CI 1.16–2.96) and adult care-giving (aOR 2.37, 95% CI 1.37–4.12) were significantly associated with any depressive episode. Participants with a depressive episode were 2–3 times more likely to report poor health perceptions.

Limitations

Study limitations include the cross-sectional design, limited sample size and possible selection biases.

Conclusions

Prevalence of depressive episodes was high. Major depressive episodes were higher in HIV-affected than HIV-infected participants. Psycho-social support similar to that of HIV treatment programmes around HIV-affected older people may be useful in reducing their vulnerability to depression.  相似文献   
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Although the mechanisms of action (MoA) of nonstructural protein 3 inhibitors (NS3i) and NS5B inhibitors (NS5Bi) are well understood, the MoA of cyclophilin inhibitors (CypI) and NS5A inhibitors (NS5Ai) are not fully defined. In this study, we examined whether CypI and NS5Ai interfere with hepatitis C virus (HCV) RNA synthesis of replication complexes (RCs) or with an earlier step of HCV RNA replication, the creation of double-membrane vesicles (DMVs) essential for HCV RNA replication. In contrast to NS5Bi, both CypI and NS5Ai do not block HCV RNA synthesis by way of RCs, suggesting that they exert their antiviral activity prior to the establishment of enzymatically active RCs. We found that viral replication is not a precondition for DMV formation, since the NS3-NS5B polyprotein or NS5A suffices to create DMVs. Importantly, only CypI and NS5Ai, but not NS5Bi, mir-122, or phosphatidylinositol-4 kinase IIIα (PI4KIIIα) inhibitors, prevent NS3-NS5B-mediated DMV formation. NS3-NS5B was unable to create DMVs in cyclophilin A (CypA) knockdown (KD) cells. We also found that the isomerase activity of CypA is absolutely required for DMV formation. This not only suggests that NS5A and CypA act in concert to build membranous viral factories but that CypI and NS5Ai mediate their early anti-HCV effects by preventing the formation of organelles, where HCV replication is normally initiated. This is the first investigation to examine the effect of a large panel of anti-HCV agents on DMV formation, and the results reveal that CypI and NS5Ai act at the same membranous web biogenesis step of HCV RNA replication, thus indicating a new therapeutic target of chronic hepatitis C.  相似文献   
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Peripheral venous blood gas (PVBG) analysis is increasingly being used as a substitute for arterial blood sampling; however, comparability has not been clearly established. To determine if the pH, PCO2 and PO2 obtained from PVBG analysis is comparable with arterial blood gas (ABG) analysis. A search was conducted of electronic databases as well as hand‐searching of journals and reference lists through December 2012 to identify studies comparing PVBG with ABG analysis in adult subjects. A systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses statement. A meta‐analysis using a random effects model was used to calculate the average difference (bias) and the limits of agreement for the venous and arterial pH, PCO2 and PO2. A total of 18 studies comprising 1768 subjects were included in the meta‐analysis. There was considerable heterogeneity between studies with I2 approaching 100%. There was little difference between the pH obtained from the PVBG and the ABG, with the arterial pH typically 0.03 higher than the venous pH (95% confidence interval 0.029–0.038). The venous and arterial PCO2 were not comparable because the 95% prediction interval of the bias for venous PCO2 was unacceptably wide, extending from ?10.7 mm Hg to +2.4 mm Hg. The PO2 values compared poorly, the arterial PO2 typically 36.9 mm Hg greater than the venous with significant variability (95% confidence interval from 27.2 to 46.6 mm Hg). PVBG analysis compares well with ABG analysis for pH estimations in adults but not to the PCO2 or PO2. These differences are sufficiently large to be of clinical significance.  相似文献   
6.
Nuevo R, Van Os J, Arango C, Chatterji S, Ayuso‐Mateos JL. Evidence for the early clinical relevance of hallucinatory‐delusional states in the general population. Objective: To analyze, in a general population sample, clustering of delusional and hallucinatory experiences in relation to environmental exposures and clinical parameters. Method: General population‐based household surveys of randomly selected adults between 18 and 65 years of age were carried out. Setting: 52 countries participating in the World Health Organization’s World Health Survey were included. Participants: 225 842 subjects (55.6% women), from nationally representative samples, with an individual response rate of 98.5% within households participated. Results: Compared with isolated delusions and hallucinations, co‐occurrence of the two phenomena was associated with poorer outcome including worse general health and functioning status (OR = 0.93; 95% CI: 0.92–0.93), greater severity of symptoms (OR = 2.5 95% CI: 2.0–3.0), higher probability of lifetime diagnosis of psychotic disorder (OR = 12.9; 95% CI: 11.5–14.4), lifetime treatment for psychotic disorder (OR = 19.7; 95% CI: 17.3–22.5), and depression during the last 12 months (OR = 11.6; 95% CI: 10.9–12.4). Co‐occurrence was also associated with adversity and hearing problems (OR = 2.0; 95% CI: 1.8–2.3). Conclusion: The results suggest that the co‐occurrence of hallucinations and delusions in populations is not random but instead can be seen, compared with either phenomenon in isolation, as the result of more etiologic loading leading to a more severe clinical state.  相似文献   
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Social Psychiatry and Psychiatric Epidemiology - Intimate partner violence (IPV) is a pervasive public health problem. Existing research has focused on reports from victims and few studies have...  相似文献   
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