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1.
Muenke syndrome, also known as FGFR3-associated coronal synostosis, is defined molecularly by the presence of a heterozygous nucleotide transversion, c.749C>G, encoding the amino acid substitution Pro250Arg, in the fibroblast growth factor receptor type 3 gene (FGFR3). This frequently occurs as a new mutation, manifesting one of the highest documented rates for any transversion in the human genome. To understand the biology of this mutation, we have investigated its parental origin, and the ages of the parents, in 19 families with de novo c.749C>G mutations. All ten informative cases originated from the paternal allele (95% confidence interval 74–100% paternal); the average paternal age at birth overall was 34.7 years. An exclusive paternal origin of mutations, and increased paternal age, were previously described for a different mutation (c.1138G>A) of the FGFR3 gene causing achondroplasia, as well as for mutations of the related FGFR2 gene causing Apert, Crouzon and Pfeiffer syndromes. We conclude that similar biological processes are likely to shape the occurrence of this c.749C>G mutation as for other mutations of FGFR3 as well as FGFR2.S.V. Rannan-Eliya and I.B. Taylor contributed equally to this work.  相似文献   
2.
The antimicrobial effects of sodium benzoate against Enterococcus faecalis and Enterococcus faecium were investigated. The MIC(90) of sodium benzoate were 64 mg/L for E. faecalis and 32 mg/L for E. faecium, while the MBC(90) were 128 mg/L and 64 mg/L, respectively. Although further studies are required for clinical evidence, sodium benzoate seems to be effective against Enterococcus spp.  相似文献   
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Transketolase is a proven biocatalytic tool for asymmetric carbon‐carbon bond formation, both as a purified enzyme and within bacterial whole‐cell biocatalysts. The performance of Pichia pastoris as a host for transketolase whole‐cell biocatalysis was investigated using a transketolase‐overexpressing strain to catalyze formation of l ‐erythrulose from β‐hydroxypyruvic acid and glycolaldehyde substrates. Pichia pastoris transketolase coding sequence from the locus PAS_chr1‐4_0150 was subcloned downstream of the methanol‐inducible AOX1 promoter in a plasmid for transformation of strain GS115, generating strain TK150. Whole and disrupted TK150 cells from shake flasks achieved 62% and 65% conversion, respectively, under optimal pH and methanol induction conditions. In a 300 μL reaction, TK150 samples from a 1L fed‐batch fermentation achieved a maximum l ‐erythrulose space time yield (STY) of 46.58 g L?1 h?1, specific activity of 155 U , product yield on substrate (Yp/s) of 0.52 mol mol?1 and product yield on catalyst (Yp/x) of 2.23g . We have successfully exploited the rapid growth and high biomass characteristics of Pichia pastoris in whole cell biocatalysis. At high cell density, the engineered TK150 Pichia pastoris strain tolerated high concentrations of substrate and product to achieve high STY of the chiral sugar l ‐erythrulose. © 2017 The Authors Biotechnology Progress published by Wiley Periodicals, Inc. on behalf of American Institute of Chemical Engineers Biotechnol. Prog., 34:99–106, 2018  相似文献   
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Antimicrobial properties of olive leaf extract on some yeast were examined in this study. Fresh olive leaf extracts were prepared using various solvents (water, ethanol, acetone, ethyl acetate) in Soxhlet apparatus. Antimicrobial effects of these extacts were tested againstSaccharomyces cerevisiae ATCC 9763,Schizosaccharomyces pombe, Saccharomyces uvarum, Candida oleophila, Metschnikowia fructicola andKloeckera apiculata. The antifungal activities of these extracts were tested by the disc diffusion assay, minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC). All extracts showed various degrees of antifungal effects with 10–28 μg/ml MIC, 20–48 μg/ml MFC and 1.5–9.3 mm inhibitory zone values against yeasts utilised, except water. The results indicated that the tested yeasts were sensitive to acetone and ethyl acetate extracts. It was determined thatSaccharomyces cerevisiae ATCC 9763 was the most resistant among the yeasts.  相似文献   
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In this article, the levels of 222Rn concentrations, annual effective doses, and excess lifetime cancer risk estimations were investigated for water samples in the city of Osmaniye, located in the southern part of Turkey. The measurements were conducted using a radon gas analyzer (AlphaGUARD PQ 2000 PRO). The arithmetic average of 222Rn concentrations was 0.44 Bq.L?1 with a geometric standard deviation of 0.19 and geometric average 0.41 Bq.L?1. The results obtained were compared with the findings of other studies. All measured radon concentrations were below the values recommended by the World Health Organization and the U.S. Environmental Protection Agency. The associated radiological parameters such as annual effective doses (AED) and excess lifetime cancer risk (ELCR) from consumption of these waters were calculated. The computed average annual effective doses for ingestion and inhalation as well as excess lifetime cancer risk were estimated to be 1.13 μSv.y?1, 1.10 μSv.y?1, and 3.95 × 10?6, respectively. 222Rn concentration, AED, and ELCR interpolated values of the region were determined and mapped using the Kriging method. The results of radon concentrations in this study provide a data baseline for future studies on subsequent evaluations of possible future environmental contamination of Osmaniye Province.  相似文献   
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The stiffness of the extracellular matrix (ECM) is known to influence cell behavior. The ability to manipulate the stiffness of ECM has important implications in understanding how cells interact mechanically with their microenvironment. This article describes an approach to manipulating the stiffness ECM, whereby magnetic beads are embedded in the ECM through bioconjugation between the streptavidin-coated beads and the collagen fibers and then manipulated by an external magnetic field. It also reports both analytical results (obtained by formal modeling and numerical simulation) and statistically meaningful experimental results (obtained by atomic force microscopy) that demonstrate the effectiveness of this approach. These results clearly suggest the possibility of creating desired stiffness gradients in ECM in vitro to influence cell behavior.  相似文献   
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It has been known for several years that heterozygous mutations of three members of the fibroblast growth-factor-receptor family of signal-transduction molecules-namely, FGFR1, FGFR2, and FGFR3-contribute significantly to disorders of bone patterning and growth. FGFR3 mutations, which predominantly cause short-limbed bone dysplasia, occur in all three major regions (i.e., extracellular, transmembrane, and intracellular) of the protein. By contrast, most mutations described in FGFR2 localize to just two exons (IIIa and IIIc), encoding the IgIII domain in the extracellular region, resulting in syndromic craniosynostosis including Apert, Crouzon, or Pfeiffer syndromes. Interpretation of this apparent clustering of mutations in FGFR2 has been hampered by the absence of any complete FGFR2-mutation screen. We have now undertaken such a screen in 259 patients with craniosynostosis in whom mutations in other genes (e.g., FGFR1, FGFR3, and TWIST) had been excluded; part of this screen was a cohort-based study, enabling unbiased estimates of the mutation distribution to be obtained. Although the majority (61/62 in the cohort sample) of FGFR2 mutations localized to the IIIa and IIIc exons, we identified mutations in seven additional exons-including six distinct mutations of the tyrosine kinase region and a single mutation of the IgII domain. The majority of patients with atypical mutations had diagnoses of Pfeiffer syndrome or Crouzon syndrome. Overall, FGFR2 mutations were present in 9.8% of patients with craniosynostosis who were included in a prospectively ascertained sample, but no mutations were found in association with isolated fusion of the metopic or sagittal sutures. We conclude that the spectrum of FGFR2 mutations causing craniosynostosis is wider than previously recognized but that, nevertheless, the IgIIIa/IIIc region represents a genuine mutation hotspot.  相似文献   
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A new method is proposed for estimating the parameters of ball joints, also known as spherical or revolute joints and hinge joints with a fixed axis of rotation. The method does not require manual adjustment of any optimisation parameters and produces closed form solutions. It is a least squares solution using the whole 3D motion data set. We do not assume strict rigidity but only that the markers maintain a constant distance from the centre or axis of rotation. This method is compared with other methods that use similar assumptions in the cases of random measurement errors, systematic skin movements and skin movements with random measurement noise. Simulation results indicate that the new method is superior in terms of the algorithm used, the closure of the solution, consistency and minimal manual parameter adjustment. The method can also be adapted to joints with translational movements.  相似文献   
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