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131.
Biosorption of Acid Blue 40 (AB40) onto cone biomass of Thuja orientalis was studied with variation in the parameters of pH, contact time, biosorbent and dye concentration and temperature to estimate the equilibrium, thermodynamic and kinetic parameters. The AB40 biosorption was fast and the equilibrium was attained within 50 min. Equilibrium data fitted well to the Langmuir isotherm model in the studied concentration range of AB40 and at various temperatures. Maximum biosorption capacity (q(max)) for AB40 was 2.05 x 10(-4)mol g(-1) or 97.06 mg g(-1) at 20 degrees C. The changes of Gibbs free energy, enthalpy and entropy of biosorption were also evaluated for the biosorption of AB40 onto T. orientalis. The results indicate that the biosorption was spontaneous and exothermic. Kinetics of biosorption of AB40 was analyzed and rate constants were also derived and the results show that the pseudo-second-order kinetic model agrees very well with the experimental data.  相似文献   
132.
Nanoemulsions have some important potential advantages over conventional emulsions for certain commercial applications due to their optical clarity, high physical stability, and ability to increase the bioavailability of lipophilic bioactives. In this study, the factors influencing droplet size and stability in nanoemulsions fabricated from a hydrocarbon oil and an anionic surfactant were examined. Octadecane oil-in-water nanoemulsions were produced by a high pressure homogenizer (microfluidizer) using sodium dodecyl sulfate (SDS) as a model anionic surfactant. The influence of homogenization pressure, number of passes, and surfactant concentration was examined. The droplet size decreased with increasing homogenization pressure, number of passes, and surfactant concentration. Nanoemulsions with low turbidity and small droplet diameters (≈62 nm) could be produced under optimized conditions. Interestingly, nanoemulsions containing relatively high surfactant levels were highly susceptible to creaming when they were only passed through the homogenizer a few times, which was attributed to depletion flocculation. These results show the importance of optimizing surfactant levels to produce small droplets that are also stable to creaming.  相似文献   
133.
OBJECTIVE: To evaluate structural alterations in rat endometrium at preimplantation following treatment with aspirin beginning from proestrus by light microscopy, electron microscopy and immunohistochemical techniques. STUDY DESIGN: Twenty rats were divided into control (n = 10) and experimental (n = 10) groups. Experimental rats were treated with low-dose aspirin daily (2 mg/kg/day) during estrus, beginning from the proestrus phase, mated at end of cycle and treated with aspirin. Untreated pregnant rats were the control group. Rats in both groups were sacrificed at the 84th pregnancy hour; the uterus was rapidly removed and dissected free of surrounding adipose tissue. Uteri specimens from nonpregnant rats were transferred into fixative solution and processed for light, electron microscopic and immunohistochemical study. RESULTS: Light and electron microscopy of endometrium from control rats conformed to mid-diestrus phase; endometrial histology of the aspirin-treated group conformed to late diestrus phase. The endometrial layer was significantly thicker in the aspirin-treated group compared to the untreated control group (p <0.001). No significant difference was found in vessel number between groups. Staining with alphaV integrin was more dense in the aspirin-treated group. CONCLUSION: Based on histologic findings, we suggest low-dose aspirin has positive effects on preparing endometrium before implantation.  相似文献   
134.
Forty‐nine Phytophthora isolates were obtained from roots and crown of apricot trees with symptoms of decline grown in commercial orchards in Malatya, Elaz?? and Diyarbak?r provinces, Turkey, in 2011 and 2013. All of the recovered isolates were identified as Phytophthora palmivora on the basis of morphological characteristics. Blast analysis of ITS region sequences of rDNA of 5 isolates revealed 100% identity with a reference isolates of P. palmivora from GenBank. Isolates of P. palmivora were pathogenic on 12‐month‐old wild apricot rootstock ‘Zerdali’ plants that were wound inoculated on the roots and on the crown. This study demonstrated that P. palmivora is the cause of the crown and root rot found on apricot in Turkey. To our knowledge, this is the first report of P. palmivora on this host plant.  相似文献   
135.
Sarcosine was recently identified as a differential metabolite that is present in urine in elevated concentration as prostate cancer develops metastases. The aim of this study is to prepare reflectometric interference spectroscopy (RIfS) nanosensors for the detection of sarcosine. Sarcosine imprinted nanoparticles were prepared by two phase miniemulsion polymerization and characterized with transmission electron microscopy, dynamic light scattering, and atomic force microscopy measurements. The glass substrates (10 × 10 mm2) were treated with Piranha solution and incubated in polyethyleneimine solution. The sarcosine imprinted nanoparticles were attached to glass substrates by spin coating of nanoparticle solution. The recognition properties of the nanosensors were evaluated by reflectometric interferometric spectroscopy. To show selectivity of sarcosine imprinted RIfS nanosensor, real‐time l ‐alanine detection was also performed. Sarcosine detection studies were performed from aqueous solution and urine sample. A good linearity was revealed with a correlation coefficient of 0.9622 and a detection limit of 45 nM. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 31:55–61, 2015  相似文献   
136.
We aimed to determine the oxidative stress and antioxidant status in preeclamptic placenta. Also, we investigated the apoptotic index of villous trophoblast and proliferation index of cytotrophoblasts. The study included 32 pregnant with preeclampsia and 31 normotensive healthy pregnant women. Malondialdehyde (MDA) and total antioxidant status (TAS) levels were measured in the placenta. For detection of apoptosis and proliferation in trophoblast, apoptosis protease activating factor 1 (APAF-1) and Ki-67 were used. Placental MDA levels in preeclamptic women were significantly higher than normal pregnancies (p = 0.002). There was no significant difference between the groups in the TAS levels of placenta (p = 0.773). Also, the apoptotic index in villous trophoblasts increased (p < 0.001), but proliferation index did not change in preeclampsia (p = 0.850). Increased oxidative stress and apoptosis in pathological placenta are not balanced by antioxidant systems and proliferation mechanisms.  相似文献   
137.
The present study deals with the possible effects of selected environmental agents upon the uptake and metabolism of d ‐glucose in isolated acinar and ductal cells from the rat submandibular salivary gland. In acinar cells, the uptake of d ‐[U‐14C]glucose and its non‐metabolised analogue 3‐O‐[14C‐methyl]‐d ‐glucose was not affected significantly by phloridzin (0.1 mM) or substitution of extracellular NaCl (115 mM) by an equimolar amount of CsCl, whilst cytochalasin B (20 μM) decreased significantly such an uptake. In ductal cells, both phloridzin and cytochalasin B decreased the uptake of d ‐glucose and 3‐O‐methyl‐d ‐glucose. Although the intracellular space was comparable in acinar and ductal cells, the catabolism of d ‐glucose (2.8 or 8.3 mM) was two to four times higher in ductal cells than in acinar cells. Phloridzin (0.1 mM), ouabain (1.0 mM) and cytochalasin B (20 μM) all impaired d ‐glucose catabolism in ductal cells. Such was also the case in ductal cells incubated in the absence of extracellular Ca2+ or in media in which NaCl was substituted by CsCl. It is proposed that the ductal cells in the rat submandibular gland are equipped with several systems mediating the insulin‐sensitive, cytochalasin B‐sensitive and phloridzin‐sensitive transport of d ‐glucose across the plasma membrane. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
138.
Corticosteroids are used to reduce the oedema and prevent scar tissue formation of the upper airways by their ability to inhibit influx of inflammatory cells, limit capillary permeability and block collagen synthesis in the early stages of wound healing. Triazolopyrimidine (Trapidil) is an antiplatelet agent that acts in part as a phosphodiesterase inhibitor and as a competitive inhibitor of the platelet-derived growth factor (PDGF) receptor. Trapidil, with its vasodilator and NO releasing effect may have some potential to diminish the tissue injury. This study was carried out to evaluate the effects of trapidil (triazolopyrimidine) on lipid peroxidation and nitric oxide in the corticosteroid-impaired healing of tracheal anastomoses. Thirty-four adult Wistar rats were divided into five groups. The animals underwent tracheal transection and primary anastomoses. The groups were assigned as follows: group I, control, (GI, n = 6); group II, sham, (GII, n = 6); group III, dexamethasone, 0.1 mg kg(-1) twice daily intramuscularly, (GIII, n = 8); group IV, trapidil, 6 mg kg(-1) twice daily intraperitoneally (GIV, n = 7); group V, dexamethasone, 0.1 mg kg(-1) plus trapidil, 6 mg kg(-1) twice daily (GV, n = 7), for 1 week. After 1 week, anastomotic healing was assessed by measurement of bursting pressure, evaluation of histopathology, measurement of MDA and nitrite/nitrate levels. In GIII, GIV and GV bursting pressures resulted in significantly reduced anastomotic strength compared to the controls (p < 0.001 for all groups). The difference between bursting pressures of GIII and GIV was not found to be statistically significant (p = 0.966). In regard to fibroblast proliferation and collagen content, a significant difference was found between GIII and GI (p < 0.01), A significant difference was also found when GIV and GV were compared to GIII (p < 0.01). MDA and nitrite/nitrate levels were found to be higher in GIII when compared to all other groups. MDA levels of GIV and GV rats were found to be lower than GIII (p < 0.001, for both groups). The nitrite/nitrate levels of GIV and GV rats were found to be lower than GIII (p < 0.05), and higher than GI (p < 0.001). Trapidil may be useful for its preventive effects on lipid peroxidation and possible increases in NO in cases with corticosteroid-impaired healing of trachea anastomoses.  相似文献   
139.
The aim of this study was to investigate the effects of propolis on oxytetracycline (OTC)-induced oxidative stress and immunosuppression in fish. OTC (100 mg per kg?1 body weight) was orally administered to fish for 14 days. A significant elevation in the level of malondialdehyde, as an index of lipid peroxidation, and reductions in antioxidant enzyme activities (superoxide dismutase, catalase, and glutathione peroxidase) and low molecular weight antioxidant (reduced glutathione) levels were observed in the blood, liver, kidney, spleen, and heart tissues of OTC-treated fish. OTC also had a suppressive effect on specific and non-specific immune system parameters, such as leucocyte counts, oxidative radical production (nitrobluetetrazolium activity), total plasma protein and immunoglobulin levels, and phagocytic activity. Pre-treatment, post-treatment, and simultaneous treatment with propolis (50 mg per kg?1 body weight, orally) attenuated the OTC-induced oxidative stress by significantly decreasing the levels of malondialdehyde in tissues. In addition, propolis significantly increased the level of reduced glutathione and the catalase, glutathione peroxidase, and superoxide dismutase activities. Upon the administration of propolis, the suppressed immune system parameters were significantly increased in fish treated with OTC. The present results suggest that pre-treatment, post-treatment, and simultaneous administration of propolis might alleviate OTC-induced oxidative stress and immunosuppression.  相似文献   
140.
Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) is one of the most important and effective predators of Tetranychus spp. (Acari: Tetranychidae). This study analyzed the effects of hexythiazox and spiromesifen resistance on biological characteristics of N. californicus. Pre-oviposition, oviposition, post-oviposition times, adult lifespan, total number of eggs laid per female, net reproductive rate (R0), intrinsic rate of increase (rm), doubling time (DT), mean generation time (T) and finite rate of increase (λ) were compared among three populations: 63.9-fold hexythiazox resistant (HEX14), 53.6-fold spiromesifen resistant (SPR13) and a susceptible base population. Pre-oviposition and oviposition times, mean number of eggs/female, adult lifespan, R0 and rm values were all significantly higher for the two resistant populations than for the susceptible population. Life tables of HEX14, SPR13 and the susceptible population showed that R0 was 35.0, 26.5 and 19.4 (females/female generation), rm was 0.35, 0.32 and 0.30 (females/female/day), DT was 1.92, 2.07 and 2.27 days, T was 9.8, 9.8 and 9.7 days, and λ was 1.43, 1.39 and 1.35 (individuals/female/day), respectively.  相似文献   
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