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61.
A meta‐analytic review of 33 studies and 41 independent samples was conducted of the effectiveness of community‐based mental health and behavioral programs for low‐income urban youth. Findings indicated positive effects, with an overall mean effect of 0.25 at post‐test. While this is comparable to previous meta‐analytic intervention research with more diverse samples, it stands in contrast to findings of the school‐based review (0.08 at post‐test) focused on this population. The current review found type of intervention to significantly moderate effects, with effects highest for programs that were environmentally based. In fact, effect sizes for programs that did not target the environment were not significant. Findings are discussed with an emphasis on environmental influences, including the differing contexts affecting school‐ versus community‐based interventions conducted with low‐income, urban youth.  相似文献   
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The World Health Organization acknowledges tuberculosis as a global threat. Tuberculosis infection is one of the top 10 causes of death worldwide. Nanotechnology and microbiology researchers are looking for new and safe nano drugs for eliminating Mycobacterium tuberculosis, the causative agent of tuberculosis. In this study, AgZnO nano‐crystals (AgZnONCs) is synthesized via the decomposition of the precursor of oxalate method. Characterization of AgZnONCs were evaluated. Next, various concentrations of AgZnONCs, as well AgZnONCs+Rifampicin, were prepared. The MTT assay was employed to study the viability of human macrophage cell lines (THP‐1) exposed to AgZnONCs. The bactericidal effects of AgZnONCs and AgZnONCs+Rifampicin were studied by Minimum Bactericidal Concentration (MBC) test. Subsequently, THP‐1 were infected by H37Rv strain of M. tuberculosis (H37RvMtb). Also, bactericidal effects of AgZnONCs and AgZnONCs+Rifampicin were compared with ex‐vivo conditions. The MBC of AgZnONCs and AgZnONCs+Rifampicin were ratios of 1:4 and 1:32 respectively (p‐value <0.05). Also, more than 50% and 80% of THP‐1 were alive in ratios of 1:4 and 1:32 in the presence of AgZnONCs, respectively. All phagocytic H37RvMtb were killed in the presence of AgZnONCs+Rifampicin (p‐value <0.05), while AgZnONCs were not able to kill all the H37RvMtb (p‐value >0.05). This study showed that, AgZnONCs+Rifampicin has the most anti‐tubercular behavior with respect to the macrophages.  相似文献   
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AIM: To determine serum γ-glutamyltransferase (GGT), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) activity, and to assess their correlation with demographic and clinical findings in healthy blood donors.METHODS: This cross-sectional study was performed in 934 male blood donors, aged 18 to 68 years, who consecutively attended Tehran blood transfusion service in 2006. All participants were seronegative for HBV or HCV infections, non alcohol users, and all underwent a standard interview and anthropometric tests. Clinical and biochemical parameters including AST, ALT, and GGT activities were determined. Patients taking drugs known to cause hepatic fat deposition were excluded. For AST, ALT, and GGT variables, we used 33.33 and 66.66 percentiles, so that each of them was divided into three tertiles.RESULTS: Mean AST, ALT, and GGT activities were 25.26 ± 12.58 U/L (normal range 5-35 U/L), 33.13 ± 22.98 (normal range 5-35 U/L), and 25.11 ± 18.32 (normal range 6-37 U/L), respectively. By univariate analyses, there were significant associations between increasing AST, ALT, or GGT tertiles and age, body weight, body mass index, and waist and hip circumferences (P < 0.05). By multiple linear regression analyses, ALT was found to be positively correlated with dyslipidemia (B = 6.988, P = 0.038), whereas ALT and AST were negatively correlated with age. AST, ALT, and GGT levels had positive correlation with family history of liver disease (B = 15.763, P < 0.001), (B = 32.345, P < 0.001), (B =24.415, P < 0.001), respectively.CONCLUSION: Although we did not determine the cutoffs of the upper normal limits for AST, ALT, and GGT levels, we would suggest screening asymptomatic patients with dyslipidemia and also subjects with a family history of liver disease.  相似文献   
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Almost all tumors harbor a defective negative feedback loop of signaling by transforming growth factor-β (TGF-β). Epigenetic mechanisms of gene regulation, including DNA methylation, are fundamental to normal cellular function and also play a major role in carcinogenesis. Recent evidence demonstrated that TGF-β signaling mediates cancer development and progression. Many key events in TGF-β signaling in cancer included auto-induction of TGF-β1 and increased expression of DNA methyltransferases (DNMTs), suggesting that DNA methylation plays a significant role in cancer development and progression. In this review, we performed an extensive survey of the literature linking TGF-β signaling to DNA methylation in prostate cancer. It appeared that almost all DNA methylated genes detected in prostate cancer are directly or indirectly related to TGF-β signaling. This knowledge has provided a basis for our future directions of prostate cancer research and strategies for prevention and therapy for prostate cancer.  相似文献   
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Reduced heart rate variability (HRV) is a hallmark of systemic inflammation which carries negative prognostic information in sepsis. Decreased HRV is associated with partial uncoupling of cardiac pacemaker from cholinergic neural control during systemic inflammation. Sepsis is a common complication in liver cirrhosis with high mortality. The present study was aimed to explore the hypothesis that endotoxin uncouples cardiac pacemaker from autonomic neural control and reduces HRV in an experimental model of cirrhosis. Cirrhosis was induced by surgical ligation of the bile duct in rats. Cirrhotic rats were given intraperitoneal injection of either saline or lipopolysaccharide (endotoxin, 1 mg/kg). Changes in HRV indices were studied in conscious rats using implanted telemetric probes. The atria were isolated and chronotropic responsiveness to cholinergic stimulation was assessed in vitro. Endotoxin injection induced a significant tachycardia and decreased short-term and long-term HRV indices in control rats. However, endotoxin was unable to increase heart rate in cirrhotic animals. In contrast with control rats, endotoxin induced biphasic changes in short-term HRV in cirrhotic rats. Acute endotoxin challenge reduced long-term HRV with 60-min delay in comparison with control animals. Endotoxin injection was associated with a significant hypo-responsiveness to cholinergic stimulation in control rats in vitro. Endotoxin did not change atrial chronotropic responsiveness to cholinergic stimulation in cirrhotic rats. Our data shows that cirrhosis is associated with development of tolerance to cardiac chronotropic effect of endotoxin in rats.  相似文献   
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This study assessed the effects of mumie (shilajit) pre-treatment, a traditional drug which is well known in the ancient medicine of both east and west, on cardiac performance of rats subjected to myocardial injury. Animals were divided into control, M250, and M500 (received mumie at dosages of 250 and 500 mg/kg/day, orally for 7 days, respectively) main groups each consisting of two subgroups—with and without heart injury. On the 6th and 7th days, isoproterenol (ISO) (85 mg/kg i.p.) was injected (s.c.) to half of the animal subgroups to induce myocardial damage. On the 8th day, after hemodynamic parameter recordings, hearts were removed for further evaluation. Mumie pre-treatment had no significant effects on hemodynamic and cardiac indices of normal animals. When the cardiac injury was induced, mumie maintained the ±dp/dt maximum, attenuated the serum cardiac troponin I, and reduced the severity of cardiac lesions. Despite the mild positive effects of mumie on total antioxidant capacity and lipid proxidation index, no significant difference was observed among animal groups. The findings suggest the prominent cardioprotective effect of mumie against destructive effects of ISO. It seems that other mechanisms than reinforcements of antioxidant system are involved in this beneficial effect.  相似文献   
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The present study aimed to assess the effect of supplementation of omega-3 and/or vitamin C on serum interleukin-6 and high sensitivity C-reactive protein concentration and depression scores among shift workers in Shahid Tondgoyan oil refinery. The study design was randomized, double-blind, placebo-controlled, parallel trial. Totally 136 shift workers with a depression score ≥10 in 21-item Beck Depression Rating Scale were randomly assigned to receive omega-3 (180 mg eicosapentaenoate acid and 120 mg docosahexaenoic acid) or/and vitamin C 250 mg or placebo twice daily (with the same taste and shape as omega-3 and vitamin C) for 60 days in four groups. Depression score, interleukin-6 and high sensitivity C-reactive protein were measured at baseline and after 60 days. This study showed that supplementation of omega-3 plus vitamin C is associated with a decrease in depression score (p<0.05). Supplementation of omega-3 without vitamin C, is associated with a reduction in depression score (p<0.0001) and high sensitivity C-reactive protein concentration (p<0.01). Therefore omega-3 supplementation showed a better effect on reducing depression score and high sensitivity C-reactive protein, but supplementation of vitamin C along with omega-3 did not have significant effect on change in C-reactive protein level compared to omega-3 alone. (Registration number: IRCT201202189056N1)  相似文献   
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