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51.
52.
Here we report a facile and novel bio-synthesis technique, using algal extract to reduce silver metal ions into Ag/AgCl nanoparticles. Different concentrations of metallic precursors of silver nitrate (0.1 mM, 0.2 mM, 0.5 mM and 1 mM) were tested with alcoholic extract prepared from biomass of Chlorella sp. for nanoparticle biosynthesis which was screened out of four species namely Chlorella sp., Lyngbya putealis, Oocystis sp. and Scenedesmus vacuolatus. The biomolecules present in the alcoholic extract assisted in the synthesis of nanoparticles by reducing the metallic salt to metal ions and acting as capping agents in order to stabilize the particles. The synthesized particles were characterized for physico-chemical properties. DLS analysis of particles prepared from Chlorella sp. shows the particles with size of 90.6 nm. These biosynthesized nanoparticles show great potential applications in antibacterial activity.

Here we report a facile and novel bio-synthesis technique, using algal extract to reduce silver metal ions into Ag/AgCl nanoparticles.  相似文献   
53.
Most fragility fractures arise among the many women with osteopenia, not the smaller number with osteoporosis at high risk for fracture. Thus, most women at risk for fracture assessed only by measuring areal bone mineral density (aBMD) will remain untreated. We measured cortical porosity and trabecular bone volume/total volume (BV/TV) of the ultradistal radius (UDR) using high‐resolution peripheral quantitative computed tomography, aBMD using densitometry, and 10‐year fracture probability using the country‐specific fracture risk assessment tool (FRAX) in 68 postmenopausal women with forearm fractures and 70 age‐matched community controls in Olmsted County, MN, USA. Women with forearm fractures had 0.4 standard deviations (SD) higher cortical porosity and 0.6 SD lower trabecular BV/TV. Compact‐appearing cortical porosity predicted fracture independent of aBMD; odds ratio (OR) = 1.92 (95% confidence interval [CI] 1.10–3.33). In women with osteoporosis at the UDR, cortical porosity did not distinguish those with fractures from those without because high porosity was present in 92% and 86% of each group, respectively. By contrast, in women with osteopenia at the UDR, high porosity of the compact‐appearing cortex conferred an OR for fracture of 4.00 (95% CI 1.15–13.90). In women with osteoporosis, porosity is captured by aBMD, so measuring UDR cortical porosity does not improve diagnostic sensitivity. However, in women with osteopenia, cortical porosity was associated with forearm fractures. © 2014 American Society for Bone and Mineral Research.  相似文献   
54.

Aim

To establish the allele distribution and statistical parameters of forensic interest for the D10S1248, D22S1045, D2S441, D1S1656, D12S391, and SE33 loci in Slovenian population and to compare allele frequencies with those from other populations.

Methods

We analyzed blood and buccal swab samples from 333 unrelated, healthy Slovenian individuals. All samples were genotyped using the AmpFlSTR NGM Kit to obtain the allele frequency data for the loci D10S1248, D22S1045, D2S441, D1S1656, and D12S391. Samples from 113 individuals were also analyzed using the PowerPlex ESX 17 system to obtain the allele frequency data for the SE33 locus. Allele frequencies and statistical parameters of forensic interest were determined and frequency profiles compared between Slovenian and other European Caucasian populations using the Arlequin software, version 3.5.1.3.

Results

The investigated short tandem repeat (STR) loci in Slovenian population had a great discriminating potential with a combined discrimination power of 0.99999998. The highest discrimination power and polymorphism information content were observed for the SE33 locus, followed by loci D1S1656, D12S391, D10S1248, D2S441, and D22S1045. When Slovenian allele frequency distribution was compared with other European populations, deviations were found only for Spanish and Italian population for D2S441 and D12S391.

Conclusion

Slovenian population does not differ significantly from other European populations in terms of allele frequency distributions for the six analyzed STR loci. Based on forensic efficiency values, SE33 may be considered the most informative locus, which makes it especially useful in forensic investigations.In their recommendations for autosomal short tandem repeat (STR) DNA typing in forensic casework, the European Network of Forensic Institutes (ENFSI) and the European DNA Profiling (EDNAP) Group proposed the use of additional five STRs, three mini-STRs (D2S441, D10S1248, D22S1045), and two highly polymorphic STRs (D1S1656 and D12S391). The increased number of the European Standard Set (ESS) loci resulted in improved discrimination power, sensitivity, and reproducibility for the analysis of minute amounts of DNA (1,2). In the last few years, several commercial STR typing kits have been released, with five new ESS loci. The new kits have been shown to be robust enough to successfully genotype even degraded DNA from old bone material (3-5). These kits also include the AmpFlSTR NGMTM PCR Amplification Kit (Applied Biosystems, Foster City, CA, USA) and the PowerPlex ESX 17 System (Promega, Madison, WI, USA), which we used for our population study. Allele frequencies for autosomal STRs (6,7), Y-chromosomal STRs (8), and mitochondrial DNA (9) were already determined for Slovenian population and the aim of this study was to apply new genetic markers in routine forensic casework to achieve higher evidential value of STR typing and to increase the number of short STR loci, which are better preserved in degraded samples. Some European population studies have already investigated the new ESS loci (D10S1248, D22S1045, D2S441, D1S1656, D12S391) and we compared Slovenian allele frequencies with them (10-17). Beside the analysis of 5 new ESS loci we also analyzed SE33 locus and compared allele frequencies with Austrian (15), Italian (16), German (18), and Spanish population (19).  相似文献   
55.
56.
Although there are recommendations, there is little evidence about the rationale for the frequency and duration of review appointments for patients with cancer of the head and neck. We have recorded the pattern of follow-up in a tertiary cancer centre and its association with survival and recurrent disease. We used clinical letters and a prospectively maintained database to obtain details on 297 patients who were treated curatively for squamous cell carcinoma (SCC) of the oral cavity between 2005 and 2008. Mean (SD) age was 63 (12) years and 58% (n = 171) were male. Most patients were seen about 6 times in year one, 3 times in year 2, twice in year 3, twice in year 4, once or twice in year 5, and once yearly beyond year 5. Fewer clinics were scheduled for and attended by patients over 75 years of age, those with overall clinical grades 0-1, and those treated by operation alone in contrast to those who also had adjuvant radiotherapy. Patients were usually seen about 15 times over the 5 years. Taking into account the stage of the tumour and overall mortality, the number and timing of follow-up visits is adequate for the needs of patients with stage II-IV disease. Those with stage I disease may be considered for discharge after the third year if they are told about the risk factors, and signs and symptoms of recurrent disease, and surveillance in primary care.  相似文献   
57.
58.
PSAPP mice expressing the ‘Swedish’ amyloid precursor protein and the M146L presenilin 1 mutations are a well‐characterized model for spontaneous amyloid β plaque formation. Centella asiatica has a long history of use in India as a memory enhancing drug in Ayurvedic literature. The study investigated whether Centella asiatica extract (CaE) can alter the amyloid pathology in PSAPP mice by administering CaE (2.5 or 5.0 g/kg/day) starting at 2 months of age prior to the onset of detectable amyloid deposition and continued for either 2 months or 8 months. A significant decrease in amyloid β 1–40 and 1–42 was detectable by ELISA following an 8 month treatment with 2.5 mg/kg of CaE. A reduction in Congo Red stained fibrillar amyloid plaques was detected with the 5.0 mg/kg CaE dose and long‐term treatment regimen. It was also confirmed that CaE functions as an antioxidant in vitro, scavenging free radicals, reducing lipid peroxidation and protecting against DNA damage. The data indicate that CaE can impact the amyloid cascade altering amyloid β pathology in the brains of PSAPP mice and modulating components of the oxidative stress response that has been implicated in the neurodegenerative changes that occur with Alzheimer's disease. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
59.
60.
Azulene-containing chalcones have been synthesized via Claisen–Schmidt condensation reaction. Their chemical structure has been established by spectroscopic methods where the 1H-NMR spectra suggested that the title chalcones were geometrically pure and configured trans (J = 15 Hz). The influence of functional groups from azulene-containing chalcones on the biological activity of the 2-propen-1-one unit was investigated for the first time. This study presents optical and fluorescent investigations, QSAR studies, and biological activity of 10 novel compounds. These chalcones were evaluated for their antimicrobial activity against Gram-positive and Gram-negative bacteria. The results revealed that most of the synthesized compounds showed inhibition against Gram-negative microorganisms, independent of the substitution of azulene scaffold. Instead, all azulene-containing chalcones exhibited good antifungal activity against Candida parapsilosis, with MIC values ranging between 0.156 and 0.312 mg/mL. The most active compound was chalcone containing azulene moieties on both sides of the 2-propene-1-one bond, exhibiting good activity against both bacteria-type strains and good antifungal activity. This antifungal activity combined with low toxicity makes azulene-containing chalcones a new class of bioorganic compounds.  相似文献   
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