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排序方式: 共有269条查询结果,搜索用时 62 毫秒
171.
172.
Yurekli AI Ozkan M Kalkan T Saybasili H Tuncel H Atukeren P Gumustas K Seker S 《Electromagnetic biology and medicine》2006,25(3):177-188
The ever increasing use of cellular phones and the increasing number of associated base stations are becoming a widespread source of nonionizing electromagnetic radiation. Some biological effects are likely to occur even at low-level EM fields. In this study, a gigahertz transverse electromagnetic (GTEM) cell was used as an exposure environment for plane wave conditions of far-field free space EM field propagation at the GSM base transceiver station (BTS) frequency of 945 MHz, and effects on oxidative stress in rats were investigated. When EM fields at a power density of 3.67 W/m2 (specific absorption rate = 11.3 mW/kg), which is well below current exposure limits, were applied, MDA (malondialdehyde) level was found to increase and GSH (reduced glutathione) concentration was found to decrease significantly (p < 0.0001). Additionally, there was a less significant (p = 0.0190) increase in SOD (superoxide dismutase) activity under EM exposure. 相似文献
173.
Short term effects of a low-carbohydrate diet in overweight and obese subjects with low HDL-C levels
Background
The aim of this study was to evaluate short-term effects of a low-carbohydrate diet in overweight and obese subjects with low HDL-C levels.Methods
Overweight (BMI between 25-30 kg/m2) or obese (BMI over 30 kg/m2) subjects with low HDL-C levels (men with HDL-C <1.03, women <1.29 mmol/l) were invited to the study. A 1400 kcal 75-gram carbohydrate (CHO) diet was given to women and an 1800 kcal 100-gram CHO diet was given to men for four weeks. The distribution of daily energy of the prescribed diet was 21-22% from CHO, 26-29% from protein and 49-53% from fat. Subjects completed a three-day dietary intake record before each visit. Anthropometric indices, body fat ratio, blood lipids, glucose and insulin were measured. Baseline and week-four results were compared with a Wilcoxon signed ranks test.Results
Twenty-five women and 18 men participated. Basal median LDL-C level of men was 3.11 and basal median LDL-C level of women was 3.00 mmol/l. After four weeks of a low-carbohydrate diet, the median energy intake decreased from 1901 to 1307 kcal/day, daily energy from carbohydrate from 55% to 33%, body weight from 87.7 to 83.0 kg and HDL-C increased from 0.83 to 0.96 mmol/l in men (p < 0.002, for all). After four weeks of a low-carbohydrate diet, the median energy intake tended to decrease (from 1463 to 1243 kcal, p = 0.052), daily energy from carbohydrate decreased from 53% to 30% (p < 0.001) and body weight decreased from 73.2 to 70.8 kg (p < 0.001) in women, but HDL-C did not significantly change (from 1.03 to 1.01 mmol/l, p = 0.165). There were significant decreases in body mass index, waist circumference, body fat ratio, systolic blood pressure, total cholesterol, triglyceride and insulin levels in all subjects.Conclusions
HDL-C levels increased significantly with energy restriction, carbohydrate restriction and weight loss in men. HDL-C levels didn't change in women in whom there was no significant energy restriction but a significant carbohydrate restriction and a relatively small but significant weight loss. Our results suggest that both energy and carbohydrate restriction should be considered in overweight and obese subjects with low HDL-C levels, especially when LDL-C levels are not elevated. 相似文献174.
Tüysüz B Demirel A Uysal S Beyer V Bartsch O 《Genetic counseling (Geneva, Switzerland)》2008,19(1):29-35
We report a 15 month old boy with prominent metopic suture, epicanthal folds, strabismus, low-set ears, microretrognathia, large anterior fontanel, bilateral simian creases, muscular hypotonia, and severe psychomotor retardation. He also had West syndrome. An electroencephalogram showed hypsarrythmia, and cranial MR indicated a myelinisation delay. Standard karyotyping showed additional material on one chromosome 9p. Using FISH, a terminal 7q duplication spanning 26 Mb in size and a terminal 9p deletion sized (at least) 9.1 Mb were identified. The father had a karyotype of t(7;9)(q33;p23) and the mother's karyotype was normal. The boy presented typical facial features of the distal 7q duplication syndrome but no genital anomalies attributable to his distal 9p deletion. We assume that the severe epilepsy is likely due to the trisomy 7q. 相似文献
175.
Marcello Locatelli Gokhan Zengin Ahmet Uysal Simone Carradori Elisa De Luca Giuseppe Bellagamba 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):60-67
The current study was carried out to evaluate multicomponent pattern, biological and enzymatic activities of seven Asphodeline taxa root extracts as useful ingredients, due to the fact that these plants are commonly used as traditional food supplements in Turkish regions. The extracts were characterized for free anthraquinones and phenolics to obtain a specific chemical fingerprint useful for quality control. These analyzes were coupled to biological and enzymatic activities in order to obtain comprehensive information of the natural product. Free anthraquinones and phenolics were determined using validated HPLC-PDA methods. Antioxidant properties were determined by different procedures including free radical scavenging, reducing power, phosphomolybdenum and metal chelating assays. Ames assay was performed to evaluate mutagenic/antimutagenic properties. Enzyme inhibitory activities were tested against cholinesterase, tyrosinase, α-amylase and α-glucosidase. From the herein reported results, Asphodeline could be valuable for the production of bioactive products or food supplements for cosmetic and pharmaceutical industries. 相似文献
176.
The effect of selenium and/or vitamin E treatments on radiation-induced intestinal injury in rats 总被引:8,自引:0,他引:8
Cytotoxic effects of ionizing radiation on gastrointestinal epithelium may be related to oxidative stress. In this study, we wanted to investigate the effects of selenium, vitamin E and selenium plus vitamin E pretreatments prior to whole abdominal irradiation on intestinal injury. Irradiation caused increased lipid peroxide and decreased GSH levels in the intestine. Intestinal superoxide dismutase and glutathione peroxidase activities were increased, but glutathione transferase activity decreased following irradiation. Selenium and/or vitamin E pretreatments ameliorated these disturbances in prooxidant-antioxidant balance. This amelioriation has been verified with histopathological findings. These results indicate that antioxidant pretreatments prior to irradiation may have some beneficial effects against irradiation-induced intestinal injury. 相似文献
177.
Biochemical and morphological characteristics of selenite-induced apoptosis in human hepatoma hep G2 cells 总被引:2,自引:0,他引:2
Celik HA Aydin HH Deveci R Terzioglu E Karacali S Saydam G Akarca U Batur Y 《Biological trace element research》2004,99(1-3):27-39
Selenium is a cellular growth inhibitor in many mammary tumor cells. To comprehend the mechanism for the selenium-induced
cell death, we examined the effects of sodium selenite, which has been one of the most extensively investigated selenium compounds,
in human hepatoma Hep G2 cells.
Cell viability gradually decreased after treatment with sodium selenite within the concentration range of 10–50 μM. Low (10 μM) selenite has shown a high-percentage laddering pattern compared to the high (25 μM) cytotoxic selenium concentration in agarose gel electrophoresis. G2M-phase enrichment was also concentration dependent. The most consistent transmission electron microscopic finding was the
existence of large lysosomes.
Based on these data, we hypothesize that sodium selenite predominantly shows its apoptotic effect over hydrogen selenite accumulation. 相似文献
178.
179.
Hatipoğlu A Kanbağli O Balkan J Küçük M Cevikbaş U Aykaç-Toker G Berkkan H Uysal M 《Bioscience, biotechnology, and biochemistry》2004,68(10):2050-2057
Hazelnut oil (HO) is rich in monounsaturated fatty acids and antioxidants. We wanted to investigate the effect of HO on lipid levels and prooxidant-antioxidant status in rabbits fed a high-cholesterol (HC) diet. An HC diet caused significant increases in lipids and lipid peroxide levels in the plasma, liver, and aorta together with histopathological atherosclerotic changes in the aorta. Glutathione levels, glutathione peroxidase, and glutathione transferase activities decreased significantly, but superoxide dismutase activity and vitamin E and C levels remained unchanged in the livers of rabbits following HC diet. HO supplementation reduced plasma, liver, and aorta lipid peroxide levels and aorta cholesterol levels together with amelioration in atherosclerotic lesions in the aortas of rabbits fed an HC diet, without any decreasing effect on cholesterol levels in the plasma or liver. HO did not alter the antioxidant system in the liver in the HC group. Our findings indicate that HO reduced oxidative stress and cholesterol accumulation in the aortas of rabbits fed an HC diet. 相似文献
180.
Deda G Caksen H Kansu A Girgin N Suskan E Uysal S Tükün A 《Genetic counseling (Geneva, Switzerland)》2004,15(3):357-361
We report a 26-month-old boy with Angelman syndrome associated with Lennox-Gastaut syndrome, who developed a rash and a persistent toxic hepatitis after lamotrigine was added to valproate therapy. The patient had typical findings of both Angelman and Lennox-Gastaut syndromes. Chromosome analysis performing by FISH analysis showed a deletion in chromosome 15 (q11.2 q11.2). Although some cases of Angelman syndrome associated with Lennox-Gastaut syndrome were reported in the literature, valproate and/or lamotrigine induced toxic hepatitis in Angelman syndrome has hitherto never been described. We conclude that VPA and LTG combination should be given with great caution or avoided in patients with Angelman syndrome. 相似文献