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PURPOSE: To examine relationships among childhood adversity, attachment style (one's core beliefs regarding the self and others), and the following risk behaviors and contexts among young men who have sex with men (YMSM): homelessness, daily substance use, participation in sex work, involvement in the criminal justice system, and being out of school or work. METHODS: Using a targeted sampling approach, we recruited 569 YMSM aged 17-28 years from natural venues in New York City including bars, clubs, parks, and bus stations. Youth completed a structured interview assessing lifetime and current risk and protective contexts and behavior. Data were analyzed using univariate and multivariate statistical methods, including hierarchical logistic regression. RESULTS: After controlling for demographic characteristics and childhood adversity, YMSM with a fearful attachment style were more likely to have been homeless (OR 2.93, 95% CI 1.65-5.18), to have participated in sex work (OR 2.35, 95% CI 1.44-3.85), to use substances daily (OR 2.79, 95% CI 1.29-6.03), to have been involved in the criminal justice system (OR 2.04, 95% CI 1.38-3.01), and to be out of school/work (OR 2.47, 95% CI 1.47-4.15). Three subgroups were particularly vulnerable: YMSM who identified as heterosexual, or bisexual, and/or transgender. CONCLUSIONS: A fearful attachment style contributes to some YMSM remaining outside of the protective systems of family, school, and work, and is associated with risky contexts where they are less likely to encounter prosocial peers and adults. Further, it is associated with risk behavior. Although gay-identified youth are generally found to have poor outcomes when compared with the general population of adolescents, in the present report, YMSM who identified as heterosexual were at particular risk. Attachment theory can guide interventions by informing how individuals experience relationships and manage developmental transitions.  相似文献   
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Multiple hormones controlling energy homeostasis regulate the expression of neuropeptide Y (NPY) and agouti-related peptide (AgRP) in the arcuate nucleus of the hypothalamus. Nevertheless, inactivation of the genes encoding NPY and/or AgRP has no impact on food intake in mice. Here we demonstrate that induced selective ablation of AgRP-expressing neurons in adult mice results in acute reduction of feeding, demonstrating direct evidence for a critical role of these neurons in the regulation of energy homeostasis.  相似文献   
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Primary tumor growth and metastasis depend on angiogenesis, which is determined by the balance between proangiogenic and antiangiogenic molecules. Interferon (IFN)-α and -β inhibit angiogenesis through downregulation of interleukin-8, matrix metalloproteinase-9, and basic fibroblast growth factor. To provide evidence for the causal role of IFN-α/β in the induction of neoplasms, their angiogenesis, and hence, progressive growth, we carried out experiments using 129S6 IFN-α/β receptor −/− mice back-crossed to BALB/c nude mice. Subcutaneous angiogenesis was determined following implantation of gelfoam sponges containing 0.4% agarose and several proangiogenic molecules. Tumorigenicity and production of lung metastasis were determined subsequent to subcutaneous and intravenous injections, respectively, of highly metastatic A375SM human melanoma cells. Carcinogenesis was induced by chronic exposure of mice to UVB radiation (5 kJ/m2, 3 times/week). Angiogenesis, tumorigenicity, and production of metastasis, as well as development of autochthonous skin tumors, were all accelerated in IFN-α/β receptor −/− mice as compared to control mice. Collectively, the data show that inability to respond to endogenous IFN-α/β (through a mutation in the IFN-α/β receptor) leads to increased susceptibility to carcinogenesis, enhanced angiogenesis, tumorigenicity, and metastasis. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Advances in Health Sciences Education - Spaced education is a learning strategy to improve knowledge acquisition and retention. To date, no robust evidence exists to support the utility of spaced...  相似文献   
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Objective: To evaluate a Dutch online speech-in-noise screening test (in Dutch: “Kinderhoortest”) in normal-hearing school-age children. Sub-aims were to study test–retest reliability, and the effects of presentation type and age on test results. Design: An observational cross-sectional study at school. Speech reception thresholds (SRTs) were obtained through the online test in a training condition, and two test conditions: on a desktop computer and smartphone. The order of the test conditions was counterbalanced. Study sample: Ninety-four children participated (5–12 years), of which 75 children were normal-hearing (≤25?dB HL at 0.5?kHz,?≤20?dB HL at 1–4?kHz). Results: There was a significant effect for test order for the two test conditions (first or second test), but not for presentation type (desktop computer or smartphone) (repeated measures analyses, F(1,75)?=?12.48, p?F(1,75)?=?0.01, p?=?0.982). SRT significantly improved by age year (first test: 0.25?dB SNR, 95% CI: –0.43 to –0.08, p?=?0.004. Second test: 0.29?dB SNR, 95% CI: –0.46 to –0.11; p?=?0.002). Conclusions: The online test shows potential for routine-hearing screening of school-age children, and can be presented on either a desktop computer or smartphone. The test should be evaluated further in order to establish sensitivity and specificity for hearing loss in children.  相似文献   
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ABSTRACT: BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a frequent cause of complicated skin and skin structure infections (cSSSI). Patients with MRSA require different empiric treatment that those with non-MRSA infections, yet no accurate tools exist to aid in stratifying the risk for a MRSA cSSSI. Objectives. To develop a simple bedside decision rule to tailor empiric coverage more accurately. METHODS: We conducted a large multicenter (N=62 hospitals) retrospective cohort study in a US-based database between April 2005 and March 2009. All adult initial admissions with ICD-9-CM codes specific to cSSSI were included. Patients admitted with MRSA vs. non-MRSA were compared with regard to baseline demographic, clinical and hospital characteristics. We developed and validated a model to predict the risk of MRSA, and compared its performance via sensitivity, specificity and other classification statistics to the healthcare-associated (HCA) infection risk factors. RESULTS: Of the 7,183 patients with cSSSI, 2,387 (33.2%) had MRSA. Factors discriminating MRSA from non-MRSA were age, African-American race, no evidence of diabetes mellitus, cancer or renal dysfunction, and prior history of cardiac dysrhythmia. The score ranging from 0 to 8 points exhibited a consistent dose-response relationship. A MRSA score of 5 or higher was superior to the HCA classification in all characteristics, while that of 4 or higher was superior on all metrics except specificity. CONCLUSIONS: MRSA is present in 1/3 of all hospitalized cSSSI. A simple bedside risk score can help discriminate the risk for MRSA vs. other pathogens with improved accuracy compared to the HCA definition.  相似文献   
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Nondisclosure of maternal HIV status to young children can negatively impact child functioning; however, many mothers do not disclose due to lack of self-efficacy for the disclosure process. This study examines demographic variations in disclosure self-efficacy, regardless of intention to disclose, and assesses the relationship between self-efficacy and child adjustment via the parent–child relationship among a sample of HIV+ mothers and their healthy children (N = 181 pairs). Mothers completed demographic and self-efficacy measures; children completed measures assessing the parent–child relationship and child adjustment (i.e., worry, self-concept, depression). Across demographics, few mothers reported confidence in disclosure. Results from covariance structural modeling showed mothers endorsing higher self-efficacy had children who reported better relationship quality, and, in turn, reported fewer adjustment difficulties; higher levels of disclosure self-efficacy also directly predicted fewer adjustment problems. Findings offer support for interventions aimed at providing mothers with skills to enhance confidence for disclosing their HIV status.  相似文献   
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