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111.
The purpose of this study was to investigate the oxidative status in experimental hypothyroidism and the antioxidant effect of taurine supplementation. Forty male Sprague Dawley rats were randomly divided into four groups (group 1, control; group 2, control + taurine; group 3, propylthiouracil (PTU); group 4, PTU + taurine). Hypothyroidism was induced by giving 0.05% PTU in drinking water for 8 weeks. Taurine was supplemented in drinking water at a concentration of 1% for 5 weeks. Plasma (p < 0.05), red blood cell (p < 0.01), liver (p < 0.001) and kidney tissue (p > 0.05) malondialdehyde levels were increased in the PTU group compared with those of the control rats and were decreased in the PTU + taurine group compared with the PTU alone group. No significant changes were observed in glutathione levels of kidney and liver in the PTU group, but taurine supplementation significantly increased the glutathione levels of these tissues. Paraoxonase and arylesterase activities were decreased in the PTU group while taurine supplementation caused no significant changes in paraoxonase and arylesterase activities. These findings suggest that taurine supplementation may play a protective role against the increased oxidative stress resulting from hypothyroidism.  相似文献   
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The mechanical, physical properties and decay resistances of particleboard made from particles impregnated with Pinus brutia bark extractives were examined. Properties included were modulus of rupture, modulus of elasticity, internal bond, thickness swelling, and weight loss according to European standards. The results showed that particleboards made from particles impregnated with bark extractives had significantly lower mechanical values than those made from unimpregnated particles. Impregnating wood particles with bark extractives improved the decay resistance and thickness swelling of particleboard. Increasing concentration of the extractives decreased the mechanical properties and improved the thickness swelling and decay resistance of the panels. Particleboards made from 1% P. brutia bark extractives met the specifications for modulus of rupture and internal bond strength for general purposes.  相似文献   
113.
Akar T  Tunali S 《Bioresource technology》2006,97(15):1780-1787
The Pb(II) and Cu(II) biosorption characteristics of Aspergillus flavus fungal biomass were examined as a function of initial pH, contact time and initial metal ion concentration. Heat inactivated (killed) biomass was used in the determination of optimum conditions before investigating the performance of pretreated biosorbent. The maximum biosorption values were found to be 13.46 +/- 0.99 mg/g for Pb(II) and 10.82 +/- 1.46 mg/g for Cu(II) at pH 5.0 +/- 0.1 with an equilibrium time of 2 h. Detergent, sodium hydroxide and dimethyl sulfoxide pretreatments enhanced the biosorption capacity of biomass in comparison with the heat inactivated biomass. The biosorption data obtained under the optimum conditions were well described by the Freundlich isotherm model. Competitive biosorption of Pb(II) and Cu(II) ions was also investigated to determine the selectivity of the biomass. The results indicated that A. flavus is a suitable biosorbent for the removal of Pb(II) and Cu(II) ions from aqueous solution.  相似文献   
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Forty-four V. dahliae isolates were collected from symptomatic vascular tissues of okra plants each from a different field in eight provinces located in the eastern Mediterranean and western Anatolia regions of Turkey during 2006- 2009. Nitrate-nonutilizing (nit) mutants of V. dahliae from okra were used to determine heterokaryosis and genetic relatedness among isolates. All isolates from okra plants were grouped into two vegetative compatibility groups (VCGs) (1 and 2) and three subgroups as 1A (13.6%, 6/44), 2A (20.5%, 9/44) and 2B (65.9%, 29/44) according to international criteria. Pathogenicity tests were performed on a susceptible local okra (A. esculentus) landrace in greenhouse conditions. All isolates from VCG1A and VCG2B induced defoliation (D) and partial defoliation (PD) symptoms, respectively. Other isolates from VCG2A gave rise to typical leaf chlorosis symptoms without defoliation. The obtained data showed that the virulence level of V. dahliae isolates from okra was related to their VCG belongings. Eighteen okra landraces from diverse geographical origins were screened for resistance to VCG2B and VCG1A of V. dahliae. The results indicated that all landraces were more susceptible to highly virulent VCG1A-D pathotype displaying D or PD symptoms depending on their susceptibility levels with a mean disease severity index of 3.52 than to less virulent VCG2B-PD pathotype of V. dahliae displaying PD and ND symptoms with a mean disease severity index of 2.52. Significant differences were observed among the landraces; however, none of them exhibited a level of resistance. Okra landraces; Çorum, Hatay Has and Şanlıurfa displayed the lowest level of susceptibility or little tolerance to both D and PD pathotypes. VCG2B of PD was prevailing in the surveyed areas and VCG1A of D was the most virulent of the VCGs identified. Introduction of resistant genotypes to Turkish okra germplasm from different sources and breeding new resistant okra cultivars are critical for the sustainability of okra production.  相似文献   
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Background

In experimentally induced puromycine aminonucleoside nephrosis (PAN) animal models, nephrotic syndrome with minimal change disease and focal and segmental sclerosis-like nephritis similar to that in human is demonstrated; however, the real mechanism of PAN is not yet elucidated. Platelet derived endothelial cell growth factor (PD-ECGF), an endothelial mitogen protein, is believed to take part in microvessel formation and in stimulation of angiogenesis and its expression has not been totally demonstrated in PAN rats yet. In this study, we aimed to examine PD-ECGF expression in acute and chronic PAN induced in rats and find out the association between its expression and the stages of angiogenesis in kidney.

Methods

For the experiment, twenty-four Male Wistar Albino rats were used and divided into four groups; control group (n = 6), pre-proteinuria group (n = 6), acute group (n = 6) and chronic group (n = 6). We compared statistically all data by One-way ANOVA Test followed by Dunn Multiple Comparison Test.

Results

Proteinurea levels in control and pre-proteinuria groups were not statistically different; however, it was remarkably higher in the acute nephrosis group and significantly greater in the chronic nephrosis group than control group (p < 0.0025). In pre-proteinuria group, the serum albumin and creatinine clearances also did not significantly differ from the control group. On the other hand, in the acute and chronic nephrosis groups, serum albumin and creatinine clearances progressively decreased (p < 0.05). In our immunohistochemical studies, we showed elevated PD-ECGF expression in glomeruli of acute and chronic PAN rats. Microscopic and ultrastructural appearances of the glomeruli of acute and chronic PAN showed various sequential steps of angiogenesis, macrophages and immature capillaries with primitive lumens and apoptotic endothelial cells in the increased mesangial matrix.

Conclusions

It is reported that acute and chronic PAN progressively increase PD-ECGF expression and following induction of angiogenesis in the affected glomeruli.  相似文献   
119.
Refined olive pomace oil (ROPO) was utilized as a source oil for production of cocoa butter-like fat. Immobilized sn-1,3 specific lipase catalyzed acidolysis of ROPO with palmitic (PA) and stearic (SA) acids was performed in a laboratory scale packed-bed reactor. Effect of reactor conditions on product formation was studied at various substrate mole ratios (ROPO:PA:SA; 1:1:1, 1:1:3, 1:3:3, 1:2:6), enzyme loads (10%, 20%, 40%), substrate flow rates (1.5, 4.5, 7.5, 15 ml/min) and solvent amounts (150, 400 ml). The highest yield (10.9% POP, 19.7% POS and 11.2% SOS) was obtained at 40% enzyme load, 1:2:6 substrate mole ratio, 45 degrees C, 7.5 ml/min substrate flow rate, 150 ml solvent and 3h reaction time. The melting profile and SFC of the product were comparable to those of CB. Polarized light microscope (PLM) images showed no drastic changes in polymorphic behavior between CB and product.  相似文献   
120.
The objective of this study is to evaluate the possible protective effects of selenium (Se) against cyclophosphamide (CP)-induced acute cardiotoxicity in rats. A total of 42 male Spraque-Dawley rats were divided into six groups (n = 7). Rats in the first group were served as control. Rats in the second group received CP (150 mg/kg) at the sixth day of experiment. Animals in the third and fourth groups were treated with only 0.5 and 1 mg/kg Se respectively for six consecutive days. Rats in the fifth and sixth groups received respective Se doses (0.5 or 1 mg/kg) for 6 days and then a single dose of CP administered on the sixth day. On day 7, the animals were sacrificed; blood samples were collected to measure malondialdehyde (MDA), glutathione (GSH), lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), and ischemia-modified albumin (IMA) levels. Heart tissues were processed routinely and tissue sections were stained with H + E for light microscopic examination. In the CP-treated rats MDA, LDH, CK-MB, and IMA serum levels increased, while GSH levels decreased. Microscopic evaluation showed that tissue damage was conspicuously lower in CP plus Se groups. Moreover, 1 mg/kg Se was more protective than 0.5 mg/kg Se as indicated by histopathological and biochemical values. In conclusion, Se is suggested to be a potential candidate to ameliorate CP-induced cardiotoxicity which may be related to its antioxidant activity.  相似文献   
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