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The adsorption of cationic basic blue 9 and anionic acid orange 51 from aqueous solution onto the calcified eggshell (ES) and its ground eggshell powder (ESP) was carried out by varying the process parameters such as agitation speed, initial dye concentration, adsorbent mass and temperature. The adsorption potential for basic blue 9 onto ESP is far lower than that for acid orange 51, mainly due to the ionic interaction between the acid dye with the sulfonate groups and the positively charged sites on the surface of ESP. The adsorption capacity of acid orange 51 onto ES is significantly smaller than that onto ESP, which is in line with their pore properties (i.e., 1 vs. 21 m(2)/g). The experimental results showed that the adsorption process can be well described with a simple model, the pseudo-second-order model. According to the equilibrium adsorption capacity from the fitting of pseudo-second order reaction model, it was further found that the Freundlich model yields a somewhat better fit than the Langmuir model in the adsorption of acid orange 51 onto ESP. In addition, an increase in adsorption temperature from 15 to 45 degrees C significantly enhances the adsorption capacity of acid orange 51 onto ESP, revealing that the adsorption should be an endothermic or chemisorption process. From the results, it is feasible to utilize the ground eggshell waste as an effective adsorbent for removal of anionic dye from aqueous solution.  相似文献   
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Band 3 of the human erythrocyte is involved in anion transport and binding of the cytoskeleton to the membrane bilayer. Human erythrocytes were treated to incorporate varying concentrations of DIDS (4,4′-diisothiocyanostilbene-2,2′-disulfonic acid) a non-penetrating, irreversible inhibitor of anion transport, and both functions of Band 3 were analyzed. The rate of efflux of 35SO4. was measured and the binding of cytoskeletal components to the membrane was evaluated by extracting the membranes with 0.1 n NaOH and analyzing for the peptides remaining with the membrane. It was found that 0.1 n NaOH extracts all the extrinsic proteins from membranes of untreated cells, while, in the case of the membranes from cells treated with DIDS, a portion of the cytoskeletal components, spectrin (Bands 1 and 2) and Band 2.1 (ankyrin, syndein) remain with the membrane. The amount of these cytoskeletal components remaining with the membrane depends on the concentrations of DIDS incorporated. The effect of DIDS on the extractability of the spectrin-Band 2.1 complex correlates well with DIDS inhibition of anion transport (r = 0.91). At DIDS concentrations which completely inhibit anion transport, about 10% of total spectrin-Band 2.1 complex remains unextracted. Another anion-transport inhibitor, pyridoxal phosphate, has no effect on binding of the cytoskeleton to the membrane. On the other hand, digestion of DIDS-pretreated intact erythrocytes with Pronase, chymotrypsin, or trypsin releases the tight binding of Band 3 to cytoskeleton on the inside of the membrane. Since trypsin does not hydrolyze Band 3 the data suggest that a second membrane protein which is trypsin sensitive may be involved with Band 3 in cytoskeletal binding.  相似文献   
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Ganoderma spp. are medical mushrooms with various pharmacological compounds which are regarded as a nutraceutical for improving health and treating diseases. This review summarizes current progress in the studies of Gamoderma ranging from bioactive metabolites, bioactivities, production techniques to clinical trials. Traditionally, polysaccharides and ganoderic acids have been reported as the major bioactive metabolites of Ganoderma possessing anti-tumor and immunomodulation functions. Moreover, recent studies indicate that Gandoerma also exerts other bioactivities such as skin lighting, gut microbiota regulation, and anti-virus effects. However, since these medical fungi are rare in natural environment, and that the cost of cultivation of fruiting bodies is high, industrial submerged fermentation of Ganoderma mycelia promotes the development of Ganoderma by dint of an increase of biomass and bioactive metabolites used for further application. In addition, various strategies for production of different metabolites are well developed, such as gene regulation, bi-stage pH, and oxygen control. To date, Ganoderma not only has become one of the most popular nutraceuticals worldwide but also has been applied to clinical trials for advanced diseases such as breast and non-small-cell lung cancer.

  相似文献   
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We report the characterization of the diheme cytochrome c peroxidase (CcP) from Shewanella oneidensis (So) using UV-visible absorbance, electron paramagnetic resonance spectroscopy, and Michaelis-Menten kinetics. While sequence alignment with other bacterial diheme cytochrome c peroxidases suggests that So CcP may be active in the as-isolated state, we find that So CcP requires reductive activation for full activity, similar to the case for the canonical Pseudomonas type of bacterial CcP enzyme. Peroxide turnover initiated with oxidized So CcP shows a distinct lag phase, which we interpret as reductive activation in situ. A simple kinetic model is sufficient to recapitulate the lag-phase behavior of the progress curves and separate the contributions of reductive activation and peroxide turnover. The rates of catalysis and activation differ between MBP fusion and tag-free So CcP and also depend on the identity of the electron donor. Combined with Michaelis-Menten analysis, these data suggest that So CcP can accommodate electron donor binding in several possible orientations and that the presence of the MBP tag affects the availability of certain binding sites. To further investigate the structural basis of reductive activation in So CcP, we introduced mutations into two different regions of the protein that have been suggested to be important for reductive activation in homologous bacterial CcPs. Mutations in a flexible loop region neighboring the low-potential heme significantly increased the activation rate, confirming the importance of flexible loop regions of the protein in converting the inactive, as-isolated enzyme into the activated form.  相似文献   
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Objectives

To systematically summarize the randomized trial evidence regarding the relative effectiveness of cognitive behavioural therapy (CBT) in patients with depression in receipt of disability benefits in comparison to those not receiving disability benefits.

Data Sources

All relevant RCTs from a database of randomized controlled and comparative studies examining the effects of psychotherapy for adult depression (http://www.evidencebasedpsychotherapies.org), electronic databases (MEDLINE, EMBASE, PSYCINFO, AMED, CINAHL and CENTRAL) to June 2011, and bibliographies of all relevant articles.

Study Eligibility Criteria, Participants and Intervention

Adult patients with major depression, randomly assigned to CBT versus minimal/no treatment or care-as-usual.

Study Appraisal and Synthesis Methods

Three teams of reviewers, independently and in duplicate, completed title and abstract screening, full text review and data extraction. We performed an individual patient data meta-analysis to summarize data.

Results

Of 92 eligible trials, 70 provided author contact information; of these 56 (80%) were successfully contacted to establish if they captured receipt of benefits as a baseline characteristic; 8 recorded benefit status, and 3 enrolled some patients in receipt of benefits, of which 2 provided individual patient data. Including both patients receiving and not receiving disability benefits, 2 trials (227 patients) suggested a possible reduction in depression with CBT, as measured by the Beck Depression Inventory, mean difference [MD] (95% confidence interval [CI]) = −2.61 (−5.28, 0.07), p = 0.06; minimally important difference of 5. The effect appeared larger, though not significantly, in those in receipt of benefits (34 patients) versus not receiving benefits (193 patients); MD (95% CI) = −4.46 (−12.21, 3.30), p = 0.26.

Conclusions

Our data does not support the hypothesis that CBT has smaller effects in depressed patients receiving disability benefits versus other patients. Given that the confidence interval is wide, a decreased effect is still possible, though if the difference exists, it is likely to be small.  相似文献   
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