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The objective of this study was to assess potential toxic effects of phenanthrene (PHE) on tissues of clam Venerupis philippinarum using parameters of antioxidant defenses and oxidative stress. Antioxidant biomarkers including ethoxyresorufin-O-deethylase (EROD), glutathione S-transferase (GST), superoxide dismutase (SOD), and glutathione (GSH), as well as DNA damage and lipid peroxidation (LPO) in gills and digestive glands of V. philippinarum, were analyzed after a 1-, 3-, 6-, 10- and 15-day exposure to seawater containing PHE at concentrations of 2, 10, 50 μg/L. The results showed that the activity of most antioxidant enzymes was induced throughout the exposure period, and different trends were detected with time of exposure. The oxidative stress could be obviously caused in the gills and digestive glands under the experimental conditions. Overall, our results show that digestive glands are more sensitive to marine environmental stressors than gills, and GSH is proposed as potential useful biomarker as it showed good correlation with the target contaminant. This could provide useful information for toxic risk assessment of environmental pollutant PHE.  相似文献   
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The Ski (Sloan-Kettering Institute) is an evolutionarily conserved protein that plays a dual role as an oncoprotein and tumor suppressor gene in the development of human cancer. The Ski oncogene was first identified as a transforming protein of the avian Sloan-Kettering retrovirus in 1986. Since its discovery, Ski has been identified as a carcinogenic regulator in a variety of malignant tumors. Later, it was reported that Ski regulates the occurrence and development of some cancers by acting as an oncogene. Ski mediates the proliferation, differentiation, metastasis, and invasion of numerous cancer cells through various mechanisms. Several studies have shown that Ski expression is correlated with the clinical characteristics of cancer patients and is a promising biomarker and therapeutic target for cancer. In this review, we summarize the mechanisms and potential clinical implications of Ski in dimorphism, cancer occurrence, and progression in various types of cancer.  相似文献   
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Growth hormone (GH) is increasingly used for treatment of pediatric brain tumors. However, controversy remains over its safety. This meta-analysis assessed whether GH treatment was associated with risk of recurrence or development of secondary neoplasm for brain tumors in children. Systematic computerized searches of PubMed and Web of Knowledge were performed. Pooled relative risks (RR) with 95% confidence interval (CI) for recurrence and/or secondary neoplasm in children who were treated with GH versus those who did not receive GH were calculated. Ten studies were included. The pooled recurrence rates were 21.0% and 44.3% in the GH-treated group and non-GH-treated group, respectively. The pooled RR for recurrence was 0.470 (95% CI 0.372–0.593; z = 6.33, p = 0.000). Begg’s test (p = 0.060) and Egger’s test (p = 0.089) suggested there was no significant publication bias. The pooled RR in sensitivity analysis was 0.54 (95% CI 0.37–0.77; z = 3.32, p = 0.001), which showed the result was robust. The pooled RR for secondary neoplasm was 1.838 (95% CI 1.053–3.209; z = 2.14, p = 0.032). Begg’s test (p = 1.000) and Egger’s test (p = 0.553) suggested there was no significant publication bias. We found no evidence that GH therapy is associated with an increased risk of recurrence for pediatric brain tumors. However, because of our small sample size, the association of GH therapy with an increased risk of secondary neoplasm is uncertain. Further prospective cohorts are needed.  相似文献   
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Thirty autosomal insertion-deletion (InDel) polymorphisms were analyzed in four populations from Iraq, Lithuania, Slovenia, and Turkey using the commercial kit Investigator® DIPplex. Genotyping issues were encountered for five of the 30 InDels. They were most probably caused by polymorphisms located in the primer binding sites. Population and forensic parameters were calculated. No significant deviations from Hardy-Weinberg equilibrium or significant linkage disequilibrium were detected. The observed heterozygosities ranged from 33% to 61% depending on the marker and the population. The combined probability of exclusion for the 30 markers was 99.7% in all four populations and the matching probabilities were 1 in 3–4 × 1012 individuals. The multidimensional scaling plot drawn from FST distances showed a good concordance between the relative position of the 15 populations included in the plot and their geographic locations.  相似文献   
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数字化、网络化、智能化和多媒体化的信息技术在现代教育中的应用已成为中国教育领域的一大热点。本文论述了南通大学在信息化环境下,在医学形态学实验教学中充分应用现代信息技术,优化实验教学手段,以提高实验教学质量。  相似文献   
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