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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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The objective of the study was to characterize the chemical constituents, antioxidant and antibacterial properties of five ecotypes of Zataria multiflora Boiss. essential oil with respect to main phytogeographic grown towns in Iran. Our investigation showed that the plants had essential oil yield ranging from 1.59 ± 0.86% to 0.99 ± 0.29% v/w. There were qualitative similarities among the oils from different origins, whereas the amounts of some components were varied. From different samples, 34, 34, 32, 29 and 53 various compounds were identified, representing 98.32%, 97.77%, 99.5%, 98.38% and 96.54% of total oils, respectively. The highest oxygenated monoterpens value in this study stood at 72.99%. Moreover, thymol, a phenolic compound of oxygenated monoterpens, was the most abundant component in GC/MS ranging from 27.05% to 64.87%. In the DPPH antioxidant assay, all samples exhibited a remarkable activity with a higher degree of IC50 = 19.7 ± 0.7 μg/ml almost similar to BHT (18.1 ± 0.4 μg/ml). Escherichia coli O157:H7 was the most resistant and Candida tropicalis was the most vulnerable organisms with MICs of 16 and 0.062 mg/ml, respectively. In conclusion, it seemed that geographical variation might have influenced the oil compounds either quantitatively or qualitatively.  相似文献   
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