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631.
Berrin Ziyadanoğullari Firat Aydin Işil Aydin Hasan Bingöl 《Archives of Agronomy and Soil Science》2013,59(4-5):371-376
Removal of Cd (II) from aqueous solution by a soil containing magnesite and thermal activated soil containing magnesite was investigated. Maximum activation temperature was determined at 700°C for 2?h and maximum adsorption capacities were determined as 4.20?mg/g for natural magnesite, 38.91?mg/g for thermal activated magnesite at 25°C respectively. Equilibrium contact time of cadmium was determined for 2?h. Adsorption of Cd (II) on soil containing magnesite conforms to Langmuir's isotherm. 相似文献
632.
The adsorption behavior of 4-vinyl pyridine and 2-hydroxyethylmethacrylate grafted poly(ethylene terephthalate) fiber toward the Hg(II) and Pb(II) ions in aqueous solutions was studied by a batch equilibration technique. The influence of the treatment time was considered as well as the pH of the solution, the initial metal ions concentration, the graft yield, and the temperature. Such parameters as the adsorption kinetics, the adsorption isotherm, and the desorption time were further studied. Maximum adsorption occurred at pH 3 and pH 6 for Hg(II) and Pb(II), respectively. The adsorption kinetics followed the mechanism of the pseudo-second-order equation for heavy metal ions. The adsorption data is a good fit with Freundlich isotherm. Desorption studies indicated that the maximum percent recovery of Hg(II) and Pb(II) was 93.4% and 76.3%, respectively with 1 M HNO3. 相似文献
633.
Summary In the present study, the effect of varied gossypol (GOSS) amounts was investigated on blood parameters, the digesta pH, villus height, villus width, and crypta depth, width of duodenum, jejunum and ileum. A total of one hundred eight Ross 308 male broilers were fed with four diet groups as follows: no gossypol (control), gossypol rate 62 mg/kg (GOSS 62), gossypol rate 124 mg/kg (GOSS 124) and gossypol rate 186 mg/kg (GOSS 186). The effect of used gossypol amounts on blood parameters was not found to be statistically significant. Increases in digesta pH values of jejunum and ileum with GOSS 186 diet group were found to be statistically significant. The results also indicated that, except duodenum villus height, there was no statistical difference effect of GOSS on epithelial cell thickness, villus height, villus width, crypta depth and crypta width of the duodenum, jejunum and ileum. There have been no clearly negative effects of higher gossypol amounts up to 186 mg/kg diets on these parameters. 相似文献
634.
635.
Chestnut blight caused by Cryphonectria parasitica is a serious disease of Castanea sativa in the Black Sea region of Turkey. During disease surveys, dieback and decline symptoms were observed on trees without apparent blight and ink disease symptoms. Black necroses, similar to those caused by Phytophthora infections, were noted on some of the chestnut coppices and saplings in one nursery in Ordu and led to an investigation into this disease complex. Only symptomatic plants showing dieback symptoms were investigated. Soil samples together with fine roots were collected from two directions, north and north‐east, approximately 150 cm away from the main stems. Phytophthora spp. were baited with young chestnut leaves. Three Phytophthora spp., P. cambivora, P. cinnamomi and P. plurivora, were identified from 12 soil samples collected from 73 locations, while from the nurseries, only P. cinnamomi was obtained. Phytophthora cinnamomi was the most common species, obtained from seven locations in five provinces and from four nurseries having similar symptoms mentioned above in different locations. Phytophthora cambivora and P. plurivora were less frequently obtained, from three to two stands, respectively. Phytophthora cinnamomi and P. cambivora were the most aggressive species when inoculated at the stem base on 3‐year‐old chestnut saplings, killing six saplings of eight inoculated in 2 months. The three Phytophthora species were first recorded on chestnut in Black sea region of Turkey with the limited samples investigated in a large area about 150 000 ha chestnut forest. 相似文献
636.
Evaluation of analgesic, anti-inflammatory and hepatoprotective effects of lycorine from Sternbergia fisheriana (Herbert) Rupr 总被引:1,自引:0,他引:1
The present study reports the potential antinociceptive, anti-inflammatory and hepatoprotective activities of lycorine from Sternbergia fischeriana (Herbert) Rupr. (Amaryllidaceae). Lycorine was evaluated on mice by using acetic-acid induced writhing and tail-flick tests. Lycorine exhibited stronger inhibition than aspirin in acetic-acid induced abdominal stretching at 1.0 mg/kg dose. Lycorine also showed antinociceptive activity at 1.0 mg/kg dose in tail-flick test. The anti-inflammatory activity of lycorine was not found to be significant at dose of 0.5 mg/kg. However, at doses of 1.0 mg/kg and 1.5 mg/kg, i.p. showed a significant reduction with 53.45% and 36.42%, respectively in rat paw oedema induced by carrageenan against the reference anti-inflammatory drug indomethacin (3 mg/kg, i.p.) (95.70%). The ED50 of lycorine was determined as 0.514 mg/kg. Hepatoprotective activity of lycorine on carbon tetrachloride (CCl4) induced acute liver toxicity following biochemical parameters were also evaluated. Rats were treated with lycorine at doses of 1.0 mg/kg and 2.0 mg/kg, i.p. Results of biochemical tests were confirmed by histopathological examination. Lycorine exhibited significant hepatoprotective effect at dose of 2.0 mg/kg i.p. dose. 相似文献
637.
638.
Turgut M Kaplan S Metin K Koca YB Soylu E Sahin B Ateşlier ZB Başaloğlu HK 《Anatomia, histologia, embryologia》2006,35(3):155-161
A better understanding of regenerative growth is very important for the development of new potential strategies. Recently, the pineal secretory product melatonin was shown to stimulate the regeneration process. In this study, we carried out an experimental investigation of tail regeneration in young adult lizards, Ophisops elegans macrodactylus Berthold, 1842, addressing the role of melatonin on the regeneration process. Lizards were divided into three groups: constant light-exposed control group (n = 13), constant dark-exposed group (n = 15) and parachlorophenylalanine (p-CPA) treatment group exposed to constant light (n = 15). Using a tail autotomy procedure, the effects of p-CPA treatment on connective tissue together with neural tissue and vascular tissue in regenerating tail in lizards were investigated. p-CPA (400 microg/kg body mass) was injected from day 0 to 30 days after autotomy. p-CPA treatment produced a significant increase in the length of the regenerated tail compared with light-exposed control and dark-exposed lizards. Total collagen content was found to be higher in p-CPA-treated animals in comparison with other groups. Histologically, a higher percentage of connective tissue and vascular tissue and a lower percentage of neural tissue were found in the regenerated tails of the p-CPA-treated lizards. Importantly, the percentage of neural tissue in lizards in the dark-exposed animals was higher than that in animals of both light-exposed and p-CPA treatment groups. Thus, it is clear that p-CPA has a stimulatory influence on fibroblast collagen production and vascularization of the regenerated tail in the lizards. Furthermore, it seems that the neural regeneration process was markedly enhanced in lizards exposed to continuous darkness. Based on the results of our study, it is suggested that melatonin may be an active factor that speeds up the rate of tail regeneration in lacertilians. 相似文献
639.
Kayserilioğlu BS Bakir U Yilmaz L Akkaş N 《Journal of agricultural and food chemistry》2003,51(4):964-968
The mechanical and physical properties of glycerol-plasticized wheat gluten films dried at different temperatures (20, 50, and 80 degrees C) and relative humidities (35 and 70% RH) were investigated. Dispersion of wheat gluten was prepared at pH 11 in aqueous solution. Films were obtained by casting the wheat gluten suspension, followed by solvent evaporation in a temperature and relative humidity controlled chamber. Decreasing relative humidity altered most of the mechanical properties. At 35% RH, tensile strength increased when drying temperature increased. However, at 70% RH, tensile strength decreased when temperature increased. Thickness of the films decreased by increasing temperature. Hypothetical coating strength increased with increasing drying temperature at 35% RH. However, at 70% RH, a maximum value was observed at 50 degrees C. Films produced at 80 degrees C exhibited low solubility in aqueous solution. Addition of 1.5% (w/v) sodium dodecyl sulfate increased solubility of all of the films except the film dried at 50 degrees C and 70% RH. Overall, drying temperature and relative humidity affected mechanical and physical properties of the wheat gluten films. However, the effect of drying temperature was more pronounced than the effect of relative humidity. 相似文献
640.
Uğur Topaloğlu Mehmet Erdem Akbalik Hakan Sağsöz 《Anatomia, histologia, embryologia》2021,50(4):726-735
Homeobox (HOX) proteins are known for their critical role in body shape formation and tissue differentiation of developing vertebrate embryos. Recent research has shown that HOX proteins have many physiological roles such as cell proliferation, cell cycle, apoptosis and cell differentiation in adults, as well as the development of the vertebrate nerve and reproductive system. This study was conducted to determine the possible physiological functions and expression intensities of HOXA10, HOXA11, HOXB6 and HOXC6 proteins in the male reproductive system (testes, epididymis and deferens ducts), which are important for the continuity of some specific cat breeds in different age ranges. In the study, a total of 18 testicular tissues were used, divided into two groups: less than 6 months (immature) and more than 1 year (mature). Tissue samples were then subjected to immunohistochemical staining with protein-specific antibodies examined in the study. In the findings obtained in the research; it was observed that HOXA10, HOXA11, HOXB6 and HOXC6 produced different intensities of immunolocalization in the epididymis and ductus deferens layers in the immature and mature testicular cells. In addition, it was found that HOXA10 immunoreaction was also seen in some vascular endothelial cells. As a result, it was concluded that the HOX proteins could contribute to the physiological functions of testes, epididymis and ductus deferens and affect male fertility. 相似文献