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121.
The genotoxic and histopathological effects of water pollution were investigated on two fish species caught from the Buyuk Menderes River and from its tributary, the Cine Stream. The Buyuk Menderes basin is an important agricultural area in Turkey. The levels of copper, zinc, cadmium, cobalt, and lead were measured at the surface of the water and in gills, liver, and muscle tissue of Chondrostoma nasus and Barbus capito pectoralis. In some tissues, the concentrations of some of these metals exceeded acceptable levels for human consumption. Zinc was found to be the most abundant metal in water and tissues. Maximal metal accumulation was observed in the liver. To detect the genotoxic potential of contaminants, the formation of micronucleus in erythrocytes was used as indicator of chromosomal damage. The frequency of micronucleus formation did not show significant differences between locations and controls in B. capito pectoralis caught from three locations and C. nasus from two locations. The histological changes included significant decreases of the mean lengths of primary and secondary lamellae. In gills epithelia, we observed cellular proliferation that developed Because of secondary lamellae fusion, ballooning degenerations, or club deformation of secondary lamellae and cystic structures in secondary lamellae. In the liver, the changes included swollen and ruptured parenchymal cells, loss of cord structure, vacuoles filled with cellular debris, focal necrosis, and a significant increase in Kupffer cells.  相似文献   
122.
We hypothesized that dexanabinol can prevent neuronal death by protecting neuronal lysosomes from nitric oxide (NO)-mediated toxicity, and in turn, by suppressing the release of cathepsins during cerebral ischemia. Focal cerebral ischemia was induced in two sets of animals by permanent middle cerebral artery occlusion. The first set was used to monitor NO concentration and cathepsin activity, while the second was used for histological examination with hematoxylin and eosin, and TUNEL staining. In post-ischemic brain tissue, NO content and cathepsin B and L activity increased (p < 0.05). Dexanabinol treatment reduced NO concentration and cathepsin activity to the control level (p > 0.05). The number of eosinophilic and apoptotic neurons increased in the post-ischemic cerebral cortex (p < 0.05). However, dexanabinol treatment lowered both of these (p < 0.05). We conclude that dexanabinol might be a useful agent for the treatment of stroke patients.  相似文献   
123.
In this study, cultivation of oyster mushroom, Pleurotus ostreatus, on wheat straw substrate containing tap water and olive mill effluent (OME) mixture containing varying volume of OME was studied in order to investigate the feasibility of using OME as an alternative wetting agent and OME's impact on some fundamental food quality characteristics of mushrooms. Time period for mycelial colonization, primordium initiation and first harvest were comparatively evaluated with the control group. It was shown that the use of OME and tap water mixture consisting of OME up to 25% volumetrically was possible for the purpose of commercial mushroom production. Experimental results obtained from substrate containing 25% OME mixture showed no statistically significant difference compared to control group. The negative effects of increasing volume of OME in the mixture were also indicated by bioefficiency, which was found to be 13.8% for substrates wetted with 100% OME, whereas bioefficiency was 53.6% for control group. Increasing volume of OME in the mixture resulted in deformation of fruit body shape, whereas no significant difference in food quality was observed due to the higher amount of OME. This work suggested that the use of OME up to 25% as moisturizer could be considered, especially for the locations having significant number of olive mills and mushroom producers, both as an environmentally friendly solution for the safe and ecological disposal of OME and a practical way for recovering OME's economic value thereby.  相似文献   
124.
Particleboard panels were made from various wood particle/needle litter of Scotch pine (Pinus sylvestris L.) mixtures bonded with urea formaldehyde resin. Litter was characterized by having higher solubility's in alcohol-benzene, with diluting alkali and hot water, and resulted in lower pH values than those of wood particles. The mechanical properties (modulus of rupture, modulus of elasticity, and internal bond strength) of boards containing up to 6.25% litter were lower than those of panels made from wood particles. However, needle litter usage improved the physical property (thickness swelling) and decay resistance of the panels, significantly. Panels consist of 6.25% and 12.50% needle litter met the minimum EN standard requirements of mechanical properties for general-purposes. Particleboards contain more than 50% needle litter had the required level of thickness swelling for 24 h immersion.  相似文献   
125.
Ethanol at 50% (v/v) and sodium bicarbonate at 1% (wt/v), either alone or in combination, were applied to organically grown strawberries 1 h before harvest to control the natural incidence of postharvest diseases. Botrytis cinerea was the major cause of decay in all of the experiments. In three experiments, ethanol significantly reduced the decay incidence after storage for 3 days at 1°C followed by 2 days at 24°C, while the efficacy of sodium bicarbonate was inconsistent. The combination of ethanol and sodium bicarbonate did not increase their efficacy. Postharvest hot water dips at 55 and 60°C for 30 s significantly reduced the decay incidence to 3.4 and 2.7%, respectively, while decay incidence in the control was 28.5% (the first experiment). The efficacy of the hot water treatments at 55 and 60°C for 30 s was consistent in three experiments. In the third experiment, the efficacy of hot water treatment at 60°C was significantly higher than that of hot water treatment at 55°C. All pre‐ and postharvest treatments significantly reduced natural fungal populations on the surfaces of fruits. None of the pre‐ and postharvest treatments caused surface injuries to the fruit or adversely affected weight loss and taste parameters.  相似文献   
126.
Mammalian Genome - Maternal nutrition during pregnancy is one of the major intrauterine environmental factors that influence fetal development by significantly altering the expression of genes that...  相似文献   
127.
128.
The rapid development of genomic technology has made high throughput genotyping widely accessible but the associated high throughput phenotyping is now the major limiting factor in genetic analysis of traits. This paper evaluates the use of thermal imaging for the high throughput field phenotyping of Solanum tuberosum for differences in stomatal behaviour. A large multi-replicated trial of a potato mapping population was used to investigate the consistency in genotypic rankings across different trials and across measurements made at different times of day and on different days. The results confirmed a high degree of consistency between the genotypic rankings based on relative canopy temperature on different occasions. Genotype discrimination was enhanced both through normalising data by expressing genotype temperatures as differences from image means and through the enhanced replication obtained by using overlapping images. A Monte Carlo simulation approach was used to confirm the magnitude of genotypic differences that it is possible to discriminate. The results showed a clear negative association between canopy temperature and final tuber yield for this population, when grown under ample moisture supply. We have therefore established infrared thermography as an easy, rapid and non-destructive screening method for evaluating large population trials for genetic analysis. We also envisage this approach as having great potential for evaluating plant response to stress under field conditions.  相似文献   
129.
Prostate cancer is a common malignancy that develops by structural mutation(s) and/or other genetic alterations in specific genes.The G to T transversions in codon 12 and C to T transitions in codon 13 of KRAS proto-oncogene are predominant point mutations that occur in about 20% of different cancers in human. In the current study it was aimed to investigate the prevalence and predictive significance of KRAS mutations in patients with prostate carcinomas. In a total of 30 fresh tumoural tissue specimens were investigated in patients with prostate carcinoma. All tumoural specimens were histo-pathologically diagnosed and genotyped for codon 12, 13 KRAS point mutations by reverse hybridisation and direct sequencing methods. KRAS mutations were found in 12 (40%) samples with 29 samples deriving from adenocarcinomas and 1 sample was small cell prostate carcinoma. In 1 (3.44%) sample codon 12 was found to be mutated and in 2 (6.8%) samples codon 13 and in 9 (31%) samples combined codon 12 and 13 were found to be mutated particularly in higher grade of tumoural tissues. Our study, based on representative collection of human prostate tumours, indicates that combined mutations in codons 12 and 13 KRAS are relatively infrequent and most commonly occur in prostate carcinomas.  相似文献   
130.
Wheat is widely grown in Turkey in the winter season, generally and weeds have been problem in production. Changes in agricultural practices such as increasing mechanization, changing cropping systems and widely use of herbicides and fertilizers has been causing some changes in weed flora in wheat fields from past to present. A contemporary weed survey was done in 2014 in the wheat fields of ?anl?urfa province, which dominate the production of Southeastern region and results were compared with a former survey done in 1967 in the same region. As a result of the comparison, flora has been notably changed; the number of weed species declined from 221 to 71 which means more than threefold diversity loss. In addition, species common over 50% of fields declined dramatically and some foremost species in the past were not recorded contemporary studies whereas some are recorded later. General density of weeds slightly increased in time with a volunteer crop (lentil) in 2014, however, without volunteer crop, the density also declined by about half. Similarly, the density and frequency of dominant species decreased markedly from past to present except some exceptions. The most important reasons for this change are increased use of herbicides and the change of the regional alternation system. It should be noted that biodiversity loss is lower than comparing to the developed world and there is a chance to conserve this through employing sustainable methods. Furthermore, problems related to weed identification were discussed using data from these surveys.  相似文献   
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