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461.
1-Naphthaleneacetamide (NAAm) is a synthetic plant growth regulator in the auxin family that is widely used in agriculture to promote the growth of numerous fruits, for root cuttings and as a fruit thinning agent. The potential genotoxic effects of NAAm were investigated in vitro by the chromosome aberrations (CAs), and cytokinesis-block micronucleus assays in human peripheral blood lymphocytes (PBLs) for the first time. The human PBLs were treated with 20, 40, 80, and 160 µg/mL of NAAm for 24 and 48 h. The results of this study showed that NAAm significantly induced the formation of structural CA and MN for all concentrations (20, 40, 80 and 160 µg/mL) and treatment periods (24 and 48 h) when compared with the negative and the solvent control. In addition, the higher concentrations of NAAm (80 and 160 µg/mL) caused a statistically significant increase in nuclear bud (NBUD) formation for both 24 and 48 h treatment times. With regard to the cell cycle kinetics, at all the tested concentrations, NAAm caused a statistically significant reduction in the mitotic index (MI) only for 48 h treatment period and also in the nuclear division index (NDI) for both 24 and 48 h treatment periods as compared to the control groups. The reductions in the MI and NDI occured in a concentration-dependent manner for both treatment times. In conclusion, the present results indicate that in the tested experimental conditions, NAAm was genotoxic and cytotoxic on human PBLs in vitro.  相似文献   
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Yüksek  Veysel  Çetin  Sedat  Usta  Ayşe 《Molecular biology reports》2020,47(10):7761-7770
Molecular Biology Reports - Prolonged and excessive fluoride exposure can lead to fluorosis. The kidney is one of the organs that are injured mostly due to fluoride-induced damage. Fluoride can...  相似文献   
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Gallic acid, a polyphenyl class natural product from gallnut and green tea, is known to be antioxidant, anti‐inflammatory and radical scavenger. In this study, we aimed to investigate the possible protective effects of gallic acid on paraoxonase and arylesterase activities in liver exposed to acute alcohol intoxication. Paraoxonase and arylesterase activities in liver tissue and serum aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase levels were measured. Histological investigations were also made. In our study, we observed a significant increase of serum alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, which are indicators of liver damage after acute ethanol consumption. Gallic acid therapy has significantly reduced the increase in these biomarkers, indicating a possible hepatoprotective effect of gallic acid. Ethanol consumption caused a significant decrease in liver paraoxonase activity (P < 0.001). Gallic acid treatment partly restored this decreased paraoxonase activity, which resulted from ethanol administration. A gallic acid dose of 100 mg/kg was observed as highest restoring effect for paraoxonase activity (P < 0.05). The activity of arylesterase was decreased in the ethanol group as compared with the control group, but this was not significant. However, 50 mg/kg of gallic acid treatment restored the loss of this activity due to ethanol exposure (P < 0.001). We observed that gallic acid ameliorates the liver damage caused by excessive alcohol consumption in a dose‐dependent way. Our results in this study showed that gallic acid might have a protective effect against alcoholic liver disease. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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One way to monitor minimal residual disease (MRD) is to screen cells for multiple surface markers using flow cytometry. In order to develop an alternative microfluidic based method, isolation of B type acute lymphoblastic cells using two types of antibodies should be investigated. The immunomagnetic beads coated with various antibodies are used to capture the B type acute lymphoblastic cells. Single beads, two types of beads and surface immobilized antibody were used to measure the capture efficiency. Both micro and nanosize immunomagnetic beads can be used to capture B type acute lymphoblastic cells with a minimum efficiency of 94% and maximum efficiency of 98%. Development of a microfluidic based biochip incorporating immunomagnetic beads and surface immobilized antibodies for monitoring MRD can be an alternative to current cost and time inefficient laboratory methods. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2737, 2019  相似文献   
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Abstract

This study involves the development and implementation of a STEM activity containing 3?D printer technology, which is commonly used in STEM education. Out of school STEM courses were organized with seven middle school students studying in the 7th grade and the activities in the course were carried out with a 3D printer. One of the activities in the course is the Balance model. The study reveals the skills students used in the Balance Model activity, which is a 3D STEM activity. The students’ engineering skills were effective through the STEM activity, and they actively used skills such as planning, designing, explaining the design process, creating a realistic product, and testing and evaluating product performance. In addition, it was concluded that the students use their academic and technical skills effectively. The study presents in detail the preparation and implementation process of this activity, which we think may help educators uncover and improve students’ engineering skills.  相似文献   
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