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641.
Bioprocess and Biosystems Engineering - In the original publication, table captions were incorrectly published. The correct captions are given here.  相似文献   
642.
The performance of a biofilm of Arthrobacter viscosus supported on granular activated carbon on the retention of organic compounds was evaluated. The presence of functional groups on the cell wall surface of the biomass that may interact with the organic compounds was confirmed by Fourier transform infrared spectroscopy, to assess the applicability of this system to the removal of those compounds. The batch assays showed that the removal percentage decreases with the increasing initial concentration. The removal of phenol ranged from 99.5 to 93.4%, the chlorophenol removal ranged from 99.3 to 61.6% and the o-cresol removal ranged from 98.7 to 73.5%, for initial concentrations between 100 and 1,700 mg/L. The batch data were described by Freundlich, Langmuir, Redlich–Peterson, Dubinin-Radushkevich, Sips and Toth model isotherms and the best fit for the retention of phenol and for the retention of o-cresol was obtained with the Sips model, while for chlorophenol, the best fit was obtained with the Freundlich model. The column tests showed that the retention performance followed the order: phenol > chlorophenol > o-cresol, and increased with the increasing initial organic compound concentration. Data from column runs were described by Adams–Bohart, Wolborska and Yoon and Nelson models with good fitting for all the models.  相似文献   
643.
A comparative study of heparin fractions obtained by affinity chromatography, electrofocusing, selective barium precipitation, polyacrylamide and agarose gel electrophoresis is reported. It is concluded that commercial heparin preparations are heterogeneous, containing at least 120 components which differ in molecular weight, in degree of affinity for antithrombin, and in their distribution in monomeric and dimeric forms. High anticoagulant activity for some heparin fractions was obtained by most of the methods used.  相似文献   
644.
Primates - Humans have used non-human primates (hereafter referred to as primates) as food source, medicine, parts of rituals, pets, and models for various studies worldwide. Here we investigated...  相似文献   
645.
Abstract

Candida species are fungal opportunistic pathogens capable of colonizing and infecting various human anatomical sites, where they have to adapt to distinct niche-specific pH conditions. The aim of this study was to analyse the features of Candida albicans and Candida glabrata biofilms developed under neutral and vaginal acidic (pH 4) conditions. C. albicans produced thicker and more filamentous biofilms under neutral than under acidic conditions. On the other hand, the formation of biofilms by C. glabrata was potentiated by the acidic conditions suggesting the high adaptability of this species to the vaginal environment. In general, both species developed biofilms containing higher amounts of matrix components (protein and carbohydrate) under neutral than acidic conditions, although the opposite result was found for one C. glabrata strain. Overall, this study contributes to a better understanding of the modulation of C. albicans and C. glabrata virulence by specific pH conditions.  相似文献   
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647.
Biological Trace Element Research - Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease of multifactorial origin. Studies have shown that trace elements such as zinc and...  相似文献   
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649.
Optimal foraging theory predicts that well-defended potential foods should be exploited only when energy pay-offs are great. Although stinging hymenopteran nests are both well-defended and predated by primates, their larvae's energy yields rarely have been calculated, and predation-linked foraging behaviours by primates infrequently documented. Based on 58 opportunistic observations of primates raiding wasp nests for larvae, we calculated energetic yields of low- and high-risk wasp nest predation for Cebus albifrons, Saimiri collinsi, S. sciureus and Sapajus apella, and tested predictions derived from optimal foraging theory. We recorded how nests were processed and by which age-sex classes, eaten nest fragment sizes, number of occupied and empty cells, and nest occupancy patterns (percent larvae/pupae, eggs, empty cells). Basal metabolic rate (BMR) calculations showed energetic yields from 15 min foraging on low-risk nests (Polybia quadricincta) would meet energy needed to sustain adult female and male C. albifrons BMR for 4.9 and 4.5 h, respectively; yields from high-risk (Chartergus artifex) nests for 6.5 and 6.2 h; Mischocyttarus sp. nest yields (low risk, but mimetically resembling other wasps) would meet S. collinsi BMR for 2.9 h (female) and 2.3 h (male), and 2.6 and 2.1 h, for the slightly larger S. sciureus, respectively. The Chartergus energetic-yield value is nearly 20% of a 36 g chocolate bar (741 kJ). Our data provide quantitative support for the common assertion that wasp larvae and pupae are high-yield foods for primates. As predicted by optimal foraging, energetic yield is sufficient to offset the risk and pain of being stung.  相似文献   
650.
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