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101.
Nitrogen and phosphorus concentration in the effluent of a wastewater treatment plant can vary significantly, which could affect the growth kinetic and chemical composition of microalgae when cultivated in this medium. The aim of this work was to study the rate of growth, nutrient removal and carbon dioxide biofixation as well as biomass composition of Scenedesmus obliquus (S. obliquus) when it is cultivated in wastewater at different nitrogen and phosphorus ratio, from 1:1 to 35:1. A more homogeneous method for calculating productivities in batch reactors was proposed. The proper N:P ratio for achieving optimum batch biomass productivity ranged between 9 and 13 (263 and 322 mg L?1 d?1 respectively). This was also the ratio range for achieving a total N and P removal. Above and below this range (9–13) the maximum biomass concentration changed, instead of the specific growth rate.The maximum carbon dioxide biofixation rate was achieved at N:P ratio between 13 and 22 (553 and 557 mg CO2 L?1 d?1 respectively). Lipid and crude protein content, both depend on the aging culture, reaching the maximum lipid content (34%) at the lowest N:P (1:1) and the maximum crude protein content (34.2%) at the highest N:P (35:1).  相似文献   
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The use of animals as a source of organs and tissues for xenotransplantation can overcome the growing shortage of human organ donors. However, the presence of xenoreactive antibodies in humans directed against swine Gal antigen present on the surface of xenograft donor cells leads to the complement activation and immediate xenograft rejection as a consequence of hyperacute reaction. To prevent hyperacute rejection, it is possible to change the swine genome by a human gene modifying the set of donor’s cell surface proteins. The gene construct pGal-GFPBsd containing the human gene encoding α-galactosidase enzyme under the promoter of EF-1α elongation factor ensuring systemic expression was introduced by microinjection into a male pronucleus of the fertilised porcine oocyte. As a result, the founder male pig was obtained with the transgene mapping to chromosome 11p12. The polymerase chain reaction (PCR) analysis revealed and the Southern analysis confirmed transgene integration estimating the approximate number of transgene copies as 16. Flow cytometry analysis revealed a reduction in the level of epitope Gal on the cell surface of cells isolated from F0 and F1 transgenic animals. The complement-mediated cytotoxicity assay showed increased viability of the transgenic cells in comparison with the wild-type, which confirmed the protective influence of α-galactosidase expression.  相似文献   
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A new species of Euphorbia sect. Brasilienses V.W. Steinm. & Dorsey is described. Euphorbia tetrangularis Hurbath & Cordeiro is endemic to the Serra de Montevidéu, a part of the Espinhaço Range located in the state of Minas Gerais, Brazil. It differs from other species within the section based on the following characters: 4-ribbed branches, green cyathia, and green cyathial glands with erect appendages. This new species would qualify as critically endangered (CR) according to IUCN criteria. An inferred phylogeny based on a combined dataset of nuclear (ITS1) and plastid regions (psbA-trnH, trnC-ycf6, matK, atpI-atpH, psbJ-petA, trnQ-rps16?×?1) confirms the monophyly of Euphorbia sect. Brasilienses and supports the recognition of E. tetrangularis. The phylogeny also suggests that this group probably underwent a recent radiation.  相似文献   
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After a survey of the special role, which the amino acid proline plays in the chemistry of life, the cell‐penetrating properties of polycationic proline‐containing peptides are discussed, and the widely unknown discovery by the Giralt group (J. Am. Chem. Soc. 2002 , 124, 8876) is acknowledged, according to which fluorescein‐labeled tetradecaproline is slowly taken up by rat kidney cells (NRK‐49F). Here, we describe details of our previously mentioned (Chem. Biodiversity 2004 , 1, 1111) observation that a hexa‐β3‐Pro derivative penetrates fibroblast cells, and we present the results of an extensive investigation of oligo‐L ‐ and oligo‐D ‐α‐prolines, as well as of oligo‐β2h‐ and oligo‐β3h‐prolines without and with fluorescence labels ( 1 – 8 ; Fig. 1). Permeation through protein‐free phospholipid bilayers is detected with the nanoFAST biochip technology (Figs. 24). This methodology is applied for the first time for quantitative determination of translocation rates of cell‐penetrating peptides (CPPs) across lipid bilayers. Cell penetration is observed with mouse (3T3) and human foreskin fibroblasts (HFF; Figs. 5 and 68, resp.). The stabilities of oligoprolines in heparin‐stabilized human plasma increase with decreasing chain lengths (Figs. 911). Time‐ and solvent‐dependent CD spectra of most of the oligoprolines (Figs. 13 and 14) show changes that may be interpreted as arising from aggregation, and broadening of the NMR signals with time confirms this assumption.  相似文献   
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ObjectivesTo estimate the prevalence of obesity and overweight in children and adolescents in our city and to investigate the associated factors.Subjects and methodsA cross-sectional study of 1317 children and adolescents aged 2-16 years. Multistage probability sampling was used to select three groups of subjects: 411 aged 12 to 16 years, 504 aged 6 to 12 years, and 402 aged 2 to 6 years. Body mass index was calculated, and obesity and overweight were diagnosed using the threshold levels of the International Obesity Task Force for children and adolescents. Parents were asked about eating habits, health, social, and demographic aspects. Results are given as percentages (95% confidence interval). The relationship between obesity and overweight and the different variables was studied using multiple logistic regression. The adjusted odds ratio (OR) was calculated.ResultsAmong children and adolescentes aged 2-16 years, 9.5% (8.0%-11.0%) were obese and 22.4% (23.3%-24.6%) were overweight. Of subjects aged 12-16 years, 8.5% (5.9%-11.2%) were obese and 20.5% (16.7%-24.3%) were overweight. In the groups aged 6-12 years and 2-6 years, rates of obesity and overweight were 11.6% (8.9% -14.3%) and 31.0% (27.0-35.0) and 8.0% (5.4%-10.6%) and 13.6% (10.3%-16.9%) respectively. Obesity or overweight was associated to age (OR 1.21; P< 0.001), maternal obesity (OR 10.99; P= 0.008), a birthweight higher than 4 kg (OR 2.91; p 0.002), and formula feeding (OR 1.82; P= 0.005).ConclusionObesity and overweight in children and adolescents are highly prevalent problems in our city.  相似文献   
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Background and objectivesTo report the prevalence of obesity in a Spanish working population and its changes in recent years.Material and methodsData were collected from routine medical examinations performed on workers by a national mutual insurance society for occupational accidents and diseases (Ibermutuamur). A structured questionnaire was completed and physical examinations were performed. Overweight was defined as BMI ranging from 25 and 29.9, obesity as BMI of 30-39.9, and morbid obesity as BMI  40 kg/m2.ResultsData from 1,336,055 medical examinations performed from May 2004 to November 2007 were collected. Prevalence rates in the population examined in 2004 (n = 230,684; 73% males; average age, 36.4 years) were: morbid obesity, 0.5% (0.6% males, 0.5% females); obesity, 14.5% (17.0% males, 7.7% females); overweight, 38.4% (44.8% males, 21.3% females). Prevalence rates of obesity and overweight were higher in blue-collar workers (16.4% and 40.5% respectively) as compared to white-collar workers (10.9% and 34.4% respectively). There was a progressive increase in prevalence of obesity during the 4-year study (2004-2007) in both males (17.0%, 17.6%, 17.9%, 18.2%) and females (7.6%, 8.0%, 8.4%, 8.7%).ConclusionsPrevalence of obesity and overweight in the Spanish working population is high, especially in male blue-collar workers, and is increasing. There is a need to promote early prevention programs and specific treatments for obesity.  相似文献   
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