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931.
The aim of our study was to assess the blood concentrations of some trace elements and melatonin (MLT) in patients with intervertebral disc herniation (IDH) and to investigate the interaction of histological and biochemical degeneration findings with aging. The present study was carried out on 13 subjects (8 women and 5 men) diagnosed with IDH. They were divided into three groups according to their ages. Nighttime serum MLT, zinc (Zn), and magnesium (Mg) levels were determined in all patients. In addition, computed tomography (CT) scan of the brain and magnetic resonance imaging examination of the lumbar spine were obtained in this study. The Zn level and Zn/Mg ratio showed a decline in patients with IDH with aging, whereas the serum Mg level and tissue hydroxyproline content increased. A positive correlation between serum Zn and MLT concentrations was found (r=0.104, p=0.734). In addition, there was a positive correlation between serum Zn level and Zn/Mg ratio (r=0.835 and p<0.01), and a negative correlation between serum Mg level and Zn/Mg ratio (r=−0.571, p<0.05). On CT study, both volume percentage of calcified pineal gland and density of calcification were found to increase progressively with advancing age. The results of semiquantitative evaluation of disc tissues of patients with IDH for histological degeneration findings showed that 66.7% of discs treated had slight degeneration in younger age group, but 75.0% and 100% of discs had moderate or marked degeneration in older age groups. Our data indicated that there is a close relationship between MLT and Zn or Mg levels in the serum samples of patients with IDH, and the levels of these elements might be affected by the presence of degeneration process and serum MLT level, or vice versa.  相似文献   
932.
The activity of proteolytic enzymes is commonly measured using casein as a substrate. A modified caseinolysis assay was developed with natural dyes such as juglone, lawsone, berberine, and quercetin for Subtilisin carlsberg, protease type XVI, and trypsin, respectively. The pH dependence and incubation time were determined. K(m), V(max), and k(cat)/K(m) values were also determined for these enzymes. Lawsone was found to be a better substrate than the others.  相似文献   
933.
934.
935.
Sex determination from skeletal human remains by discriminant function analysis is one of the methods utilized in the forensic and osteoarcheological sciences. The purpose of the present study is to establish metric standards for sex determination for medieval Anatolian populations using scapular measurements. The database for this research consisted of 93 adult skeletal remains (47 males and 46 females) from the Dilkaya medieval collection. Four measurements were taken: maximum scapular height, maximum scapular breadth, glenoid cavity height, glenoid cavity breadth, and subjected to discriminant function analysis. All measurements demonstrated some degree of sexual dimorphism, with the highest accuracy of sex determination (94.8%) obtained using maximum scapular breadth. Overall accuracies of the functions ranged from 82.9% to 95.0%, with a higher accuracy rate obtained for female skeletons than for males. Population specific discriminant formulas were developed using combinations of measurements, which can be used in ancient Anatolian populations.  相似文献   
936.
The aim of this study was to determine the possible genotoxic effects of boric acid (BA) (E284), which is used as an antimicrobial agent in food, by using sister chromatid exchange (SCEs) and chromosome aberration (CAs) tests in human peripheral lymphocytes. The human lymphocytes were treated with 400, 600, 800, and 1000 μg/mL concentrations of BA dissolved in dimethyl sulfoxide (DMSO), for 24 h and 48 h treatment periods. BA did not increase the SCEs for all the concentrations and treatment periods when compared to control and solvent control (DMSO). BA induced structural and total CAs at all the tested concentrations for 24 and 48 h treatment periods. The induction of the total CAs was dose dependent for the 24 h treatment period. However, BA did not cause numerical CAs. BA showed a cytotoxic effect by decreasing the replication index (RI) and mitotic index (MI). BA decreased the MI in a dose-dependent manner for the 24 h treatment period.  相似文献   
937.
Long-term use of Cyclosporin A (CsA) and Tacrolimus is known to yield serious untoward side effects including nephrotoxicity, neurotoxicity, and malignant tumor formation. Sister chromatid exchange (SCE) is used to assess the genotoxic potential of various agents. A total of 37 postrenal transplant patients receiving either CsA (n = 20) or Tacrolimus (n = 17) were included in this study. The genotoxic effects of CsA and Tacrolimus were assessed by determination of SCE frequency. In patients receiving CsA, SCE frequency was increased significantly compared to that in the control group (p = 0.001), whereas Tacrolimus did not yield such a significant change (p = 0.801). SCE frequency was not correlated with drug dosage (p > 0.05). Our results indicate that the use of CsA, but not Tacrolimus 506, is associated with an increased genotoxic effect in postrenal transplant patients.  相似文献   
938.
Chrysin (CH) or 5,7‐dihydroxyflavone is a flavonoid present in various plants, bee propolis, and honey. Cyclophosphamide (CYP) is a chemotherapeutic drug, which is extensively used in the treatment of multiple human malignancies. In our study, we aimed to investigate the effects of CYP and CH on some metabolic enzymes including carbonic anhydrase, aldose reductase, paraoxonase‐1, α‐glycosidase, acetylcholinesterase, and butyrylcholinesterase enzyme activities in the brain, heart, testis, liver, and kidney tissues of rats. Thirty‐five adult male Wistar rats were used. The animals were pretreated with CH (25 and 50 mg/kg b.w.) for seven days before administering a single dose of CYP (200 mg/kg b.w.) on the seventh day. In all the tissues, the treatment of CH significantly regulated these enzyme activities in CYP‐induced rats. These results showed that CH exhibited an ameliorative effect against CYP‐induced brain, heart, liver, testis, and kidney toxicity.  相似文献   
939.
Aquatic Ecology - Phytoplankton biomass, diversity, functional groups (FGs), and environmental parameters in three shallow lakes were evaluated to show the inter-annual fluctuations in...  相似文献   
940.

Under changing climate, trace elements like selenium (Se) have emerged as vital constituent of agro-ecosystems enabling crop plants to off-set the adverse effects of suboptimal growth conditions. The available form of selenium is important for boosting its bioavailability to crop plants having varied agro-botanical traits and root architectural systems. As compared to selenite, the selenate has a weaker soil bonding, higher absorption in the soil solution which results in a comparatively absorption by plant roots. Various factors including dry climate, high pH, optimal ambient air temperature, less accumulation of water, and low concentration of organic matter in the soil tend to boost the selenate ratio in the soil. The use of selenium pelleted seeds has emerged as an interesting and viable alternative to alleviate selenium deficiency in agricultural eco-systems. Similarly, the co-inoculation of a mixture of Selenobacteria and Arbuscular mycorrhizal fungi represents an evolving promising strategy for the bio-fortification of wheat plants to produce selenium-rich flour to supplement human dietary needs. Furthermore, in-depth research is required to assure the effectiveness of biological fertilization procedures in field conditions as well as to explore and increase our understanding pertaining to the underlying main mechanisms and channels of selenium absorption in plants. The focus of this review is to synthesize the recent developments on Se dynamics in soil-plant systems and emerging promising strategies to optimize its levels for crop plants. Recent developments regarding the use of micro-organisms as a biotechnological mean to enhance plant nutrition and crop quality have been objectively elaborated. The study becomes even more pertinent for arid and semi-arid agro-ecosystems owing to the potential role of selenium in providing stress tolerance to crop plants. Moreover, this review synthesizes and summarizes the recent developments on climate change and bioavailability, and the protective role of selenium in crop plants.

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