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Background: RNA isolation from ossified bone is a difficult and time-consuming process which often results in poor recovery of RNA. The yield is limited and might not be suitable for gene quantification studies by real time PCR. Methodology: The present study demonstrates RNA extraction from rat femur utilizing the silica column along with the trizol reagent. Quality of RNA was assessed by agarose gel analysis and its suitability for real-time PCR analysis was determined by β-actin Ct values. Results: The RNA isolated using silica columns in conjugation with trizol reagent resulted in higher yield of RNA and purity (A260/280=2.04; yield =1545.73 µg/ml) compared to the trizol method alone (A260/280=1.85; yield =571.2 µg/ml). Ct value of β actin obtained from RNA isolated by trizol method was higher than the Ct value obtained by trizol in conjugation with the column method (31.41 and 15.41 respectively). Conclusion: Combination of trizol along with silica column resulted in better quality and improved yield of RNA suitable for gene quantification by Real time PCR.  相似文献   
183.
Highlights? A concept to explain the production of AD-associated Aβ42(43) is proposed ? Aβ42(43) is not only a product of, but also a substrate for, γ-secretase in cells ? The mechanism underlying the action of γ-secretase modulators is proposed ? Enhancing γ-secretase function to cleave Aβ42(43) is a strategy for anti-AD drugs  相似文献   
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Russian Journal of Bioorganic Chemistry - Cyanamides, tetrazole and their derivatives have pharmaceutically attracted much attention because of their wide range of biological activities such as...  相似文献   
185.
Botryococcus braunii is a green colonial fresh water microalga and it is recognized as one of the renewable resources for production of liquid hydrocarbons. CFTRI-Bb-1 and CFTRI-Bb-2 have been reported for the first time and their performance with regard to growth and biochemical profile is presented here. The present study focused on effect of carbon dioxide (CO2) on biomass, hydrocarbon, carbohydrate production, fatty acid profile, and carotenoid content in various species of B. braunii (LB-572, SAG 30.81, MCRC-Bb, N-836, CFTRI-Bb-1, and CFTRI-Bb-2) at 0.5, 1.0, and 2.0% (v/v) levels using a two-tier flask. CO2 at 2.0% (v/v) level enhanced growth of the organism, and a two-fold increase in biomass and carotenoid contents was observed in all the B. braunii strains studied compared with control culture (without CO2 supplementation). At 1% and 2% (v/v) CO2 concentrations, palmitic acid and oleic acid levels increased by 2.5 to 3 folds in one of the strains of B. braunii (LB-572). Hydrocarbon content was found to be above 20% at 2% CO2 level in the B. braunii LB-572, CFTRI-Bb-2, CFTRI-Bb-1, and N-836 strains, whereas it was less than 20% in the SAG 30.81 and MCRC-Bb strains compared with control culture. This culture methodology will provide information on CO2 requirement for growth of algae and metabolite production. B. braunii spp. can be grown at the tested levels of CO2 concentration without much influence on culture pH.  相似文献   
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Jain K  Seetharaman S 《Genetics》2011,189(3):1029-1043
We consider an asexual population under strong selection-weak mutation conditions evolving on rugged fitness landscapes with many local fitness peaks. Unlike the previous studies in which the initial fitness of the population is assumed to be high, here we start the adaptation process with a low fitness corresponding to a population in a stressful novel environment. For generic fitness distributions, using an analytic argument we find that the average number of steps to a local optimum varies logarithmically with the genotype sequence length and increases as the correlations among genotypic fitnesses increase. When the fitnesses are exponentially or uniformly distributed, using an evolution equation for the distribution of population fitness, we analytically calculate the fitness distribution of fixed beneficial mutations and the walk length distribution.  相似文献   
188.

Chlorella vulgaris is known for its protein, growth factor, and nutritional constituents. Chlorella vulgaris was cultivated in a 1000-L outdoor open raceway pond with a maximum volumetric productivity of 130 mg L-1 day-1. The harvested biomass was dried through different methods, viz., sun drying (30 °C), oven drying (60 °C), lyophilization (?110 °C), drum drying (120 °C), and spray drying (100–150 °C). The effect of the drying method on proximate composition, pigments (chlorophyll, carotenoids), bioactive compounds (total phenolic content, flavonoid content), vitamin B12, antioxidant properties (ferric reducing antioxidant power, DPPH, and total antioxidant activity), and the color quality of C. vulgaris biomass was evaluated. Surface characterization by scanning electron microscopy (SEM) and functional group characterization through Fourier transform infrared spectroscopy were also performed. The biomass dried through lyophilization and sun drying retained maximum bioactive compounds and antioxidant activities. In contrast, drum drying resulted in a loss of nutrients, viz., protein (up to 44%), lipid (up to 41%), vitamin B12 (up to 40%), total phenolic content (> 50%), total flavonoid content (> 50%), and antioxidant activity (> 50%). Oven drying led to a loss of 30% in total flavonoid content and 17% in ferric reducing antioxidant power. SEM showed the destruction of cell wall integrity in the drum-dried sample and porous structure in the spray-dried sample. This study suggests that drying methods affect the nutrients and bioactive compounds of C. vulgaris biomass, and therefore a drying method should be selected carefully depending on the end use of the biomass.

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Bioprocess and Biosystems Engineering - The freshwater green algae, Scenedesmus obtusus, was cultivated in a 3.4 L airlift photobioreactor. The hydrodynamic parameters were estimated at...  相似文献   
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