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61.
Objective  The purpose of this study was to determine a possible relation between exposure to extremely low frequency magnetic field (ELF-MF) and the human antioxidant activity. Methods  The total serum antioxidant status (TAS), red blood cells (RBCs) glutathione peroxidase (GPX) and superoxide dismutase (SOD) were measured in 46 spot welders who were occupationally exposed to ELF-MF (magnetic field strength = 8.8–84 microTesla (μT), frequency = 50 Hertz (Hz) and electric field strength = 20–133 V/m). The results were compared with a nonexposed ELF-MF control group. The correlation between magnetic field strength and antioxidant activity in RBCs and plasma was then assessed. Results  No significant differences in TAS levels were observed (P value = 0.065). However, in RBCs of exposed group, a significant decrease in SOD and GPX activities was observed (P value = 0.001 and 0.003, respectively). This decrease was measured as 22 and 12.3%, respectively. Furthermore, a significant negative correlation between SOD/GPX activities and magnetic field intensity was observed (coefficients of SOD: −0.625, significance: 0.0001 and coefficients of GPX: −0.348, significance: 0.018). Conclusion  The results of this study indicate that ELF-MF could influence the RBC antioxidant activity and might act as an oxidative stressor. Intracellular antioxidant enzymes such as SOD and GPX were found to be the most important markers involving in this process. The influence of magnetic field on the antioxidant activity of RBCs might occur even at the recommended levels of exposure.  相似文献   
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ObjectivesNigella sativa (NS) is a known medicinal herb with numerous therapeutic effects such as antidiabetic, anti-proliferative, anti-inflammatory, and anti-cancer activities. It has been indicated that NS can regulate cellular metabolism by adjusting transduction signaling pathways. Adenosine monophosphate-activated protein kinase (AMPK) is one of the main physiological processes, such as energy hemostasis, cellular metabolism, and autophagy regulators. Herb-derived medicines have always been considered as one of the main AMPK activators, and surprisingly recent data has demonstrated that it can be a target for NS and its derivatives.Evidence acquisitionThe literature search was conducted in PubMed, SCOPUS, Embase, ProQuest, and Google Scholar electronic resources. Published articles up to September 2020 were considered, and those of which investigated Nigella sativa effects on the AMPK pathway after meeting the inclusion criteria were included.ResultsThe search was performed on several online databases such as PubMed, Scopus, Embase, ProQuest, and Google Scholar from inception until January 2020. Among the initial search, 245 studies were found. After removing duplicated data and meeting the inclusion criteria, only 14 studies were selected. They included the effects of NS and its bioactive compounds as anti-hyperglycemic (n = 5), on liver function (n = 4), cancers (n = 3), and on Neuroinflammation and Atherosclerosis (n = 2). Most of the included studies are animals or in-vitro investigations.ConclusionIn this review, we discuss the latest findings on the molecular mechanism of NS effecting the AMPK signaling pathway. We also focus on the therapeutic effects of NS, including the prevention and treatment of metabolic and pro-inflammatory disease by targeting the AMPK pathway.Graphical abstract  相似文献   
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Lead is an old environmental metal which is presented everywhere and lead poisoning is an important health issue in many countries in the world including Iran. It is known as a silent environmental disease which can have life-long adverse health effects. In children, the most vulnerable population, mental development of children health effects is of the greatest influence. Low level lead exposure can significantly induce motor dysfunctions and cognitive impairment in children. The sources of lead exposure vary among countries. Occupational lead exposure is an important health issue in Iran and mine workers, employees of paint factories, workers of copying centers, drivers, and tile making factories are in higher risk of lead toxicity. Moreover lead processing industry has always been a major of concern which affects surface water, drinking waters, and ground waters, even water of Caspian Sea, Persian Gulf and rivers due to increasing the number of industries in vicinity of rivers that release their waste discharges into river or sea. In addition, lead contamination of soil and air especially in vicinity of polluted and industrialized cities is another health problem in Iran. Even foods such as rice and fishes, raw milk, and vegetables which are the most common food of Iranian population are polluted to lead in some area of Iran. Adding lead to the opium is a recently health hazard in Iran that has been observed among opium addicts. There are few studies evaluated current status of lead exposure and toxicity in the Iranian children and pregnant women which should be taken into account of authorities. We recommend to identify sources, eliminate or control sources, and monitor environmental exposures and hazards to prevent lead poisoning.  相似文献   
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Silica nanoparticles can be potentially considered the carriers of controlled drug systems. In this research, non‐steroidal anti‐inflammatory drugs were used. Diclofenac sodium and piroxicam were loaded on the considered nanosilica using solvent evaporation method. To prove drug encapsulation on the nanosilica and its rate, infrared spectroscopy, X‐ray diffraction, and BET were used, and after proving the existence of the drug in the nanosilica matrix and determining the amount of loading, dissolution test was performed in an environment similar to that of stomach and intestine in terms of pH. Drug loading percentage showed that over 90% of drugs were loaded on nanosilica. Dissolution tests in stomach pH environment showed the control samples (drug without SBA‐15) released considerable amount of drugs (about 90%) within first 15 min, when it was about 10–20% for the matrixes. Furthermore, release rate of drugs from matrixes has shown slower rate in comparison with control samples. It was indicated nanosilica has the ability of retaining the drugs in acidic pH and prevented their release. Furthermore, the drugs were released in a controlled manner in small intestine, which is the main absorption site.  相似文献   
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Long-term effects of propolis administration on serum biochemical parameters of rainbow trout (Oncorhynchus mykiss) were investigated. To determine the possible toxicity and side effects of propolis, fish were fed on diets containing 0, 0.5, 1.5, 4.5 and 9 g propolis/kg diet for 8 weeks. At the end of the experiment, various seric biochemical parameters were determined. Our results showed that all dosages induced no significant alterations in growth parameters and the seric levels of total protein, albumin, globulin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglycerides and activities of glutamic pyruvic transaminase, glutamic oxaloacetic transaminase, alkaline phosphatase and lactate dehydrogenase, when compared to the control group. On the basis of our findings, propolis is a non-toxic substance for rainbow trout and its long-term administration might not have any side effects.  相似文献   
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Little attention has been paid to the effectiveness of hypnosis in improving the results of surgery in Iran. One hundred and twenty patients scheduled for laparoscopic cholecystectomy were randomly divided into either control (standard care) or experimental (hypnosis) groups. Prior to surgery and again after surgery, abdominal pain, nausea, and vomiting were assessed. The results suggest that hypnosis could effectively reduce pain after laparoscopic cholecystectomy and significantly reduce hospitalization time.  相似文献   
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