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61.
The International Journal of Life Cycle Assessment - Agro-food systems are involved with considerable environmental impacts. Tomato as an important vegetable crop is processed into some products...  相似文献   
62.
Applied Microbiology and Biotechnology - Concrete is arguably one of the most important and widely used materials in the world, responsible for the majority of the industrial revolution due to its...  相似文献   
63.
Bacterial cell immobilization is a novel technique used in many areas of biosciences and biotechnology. Iron oxide nanoparticles have attracted much attention in bacterial cell immobilization due to their unique properties such as superparamagnetism, large surface area to volume ratio, biocompatibility and easy separation methodology. Adhesion is the basis behind many immobilization techniques and various types of interactions determine bacterial adhesion. Efficiency of bacterial cell immobilization using iron oxide nanoparticles (IONs) generally depends on the physicochemical properties of the IONs and surface properties of bacterial cells as well as environmental/culture conditions. Bacteria exhibit various metabolic responses upon interaction with IONs, and the potential applications of iron oxide nanoparticles in bacterial cell immobilization will be discussed in this work.  相似文献   
64.
Surface plasmon polariton (SPP) excitation of the coupled light at small contact area of chromium pillars as the interface of metastructured gold funnel layer and silica medium can be enhanced locally in the gold meta-funnel-structured filter. In the present investigation, the filter is comprised of three layers, namely gold meta-funnels, nano-sized chromium pillars, and silica as the substrate. The incoming infrared (IR) waves, coupled with the excited plasmons at the first and second layers, form an excitation, known as deformed plasmon polariton. Asymmetric distribution of localized SPPs takes place owing to the inherent converging plasmonic feature of the gold funnel structure. The formation of reflection peaks with different magnitudes at different incidence angles of the polarized wave in the spectral characteristics makes the structure prominent for filtering the IR waves. Moreover, the gold meta-funnel-structured filter possesses the additional feature of distinguishing the type of polarized incidence wave. It was found that the transmission remains maximum corresponding to the normal incidence of the TE-polarized waves, whereas the TM-polarized waves over the same wavelength range are almost blocked for any value of incidence angle. The existence of transmission peaks corresponding to the TE waves demonstrates another application of this device as metastructured polarizer filter.  相似文献   
65.
Biotransformation of hydrocortisone by a natural isolate of Nostoc muscorum   总被引:1,自引:0,他引:1  
Hydrocortisone was converted in the culture of an isolated strain of the cyanobacterium Nostoc muscorum PTCC 1636 into some androstane and pregnane derivatives. The microorganism was, isolated during a screening program from soil samples collected from paddy fields of north of Iran. The bioproducts obtained were purified using chromatographic methods and identified as 11beta-hydroxytestosterone, 11beta-hydroxyandrost-4-en-3,17-dione and 11beta,17alpha,20beta,21-tetrahydroxypregn-4-en-3-one on the basis of their spectroscopic features.  相似文献   
66.

Background:

Half of the cases of vision loss in people under 60 years of age have been attributed to age-related macular degeneration (AMD). This is a multifactorial disease with late onset. It has been demonstrated that many different genetic loci are implicated in the risk of developing AMD in different populations. In the current study, we investigated the association of high-temperature ‎requirement A-1 (HTRA1) gene polymorphisms with the risk of developing AMD in the Iranian population.

Methods:

Genomic DNA samples were extracted from 120 patients with AMD and 120 healthy age- and sex-matched controls. A 385 base-pair fragment of the HTRA1 gene promoter region was amplified using the polymerase chain reaction (PCR) technique and sequenced. The frequencies of the alleles were calculated and statistical analysis was performed using SPSS software.

Results:

Our study demonstrated that the rate of polymorphisms rs11200638 -625 G>A and rs2672598 -487T>C were significantly greater in AMD patients than in healthy controls from the Iranian population.

Conclusions:

The results of our study indicate that HTRA1 gene promoter region polymorphisms are associated with the risk of developing AMD in the Iranian population.Key Words: HTRA1, Single Nucleotide Polymorphisms, Macular Degeneration, Iran  相似文献   
67.
Reduced nitric oxide availability and a heterogeneous pattern of nitric oxide synthase activity in some tissues have been reported in hypothyroidism. This study aimed at determining the effects of oral nitrate and l-arginine administration on serum, heart, and aorta nitric oxide metabolite concentrations in fetal hypothyroid rats. In an experimental study, pregnant Wistar rats were administrated tap water or 0.02 % of 6-propyl-2-thiouracil in drinking water during pregnancy and their male pups were followed (n?=?8/group). In adult progeny, serum, heart, and aorta nitric oxide metabolite concentrations were measured by the Griess method after 1-week administration of sodium nitrate (500 mg/L) or l-arginine (2 %) in drinking water. Serum thyroid hormone and thyroid-stimulating hormone levels were also measured. Compared to controls, fetal hypothyroid progeny had significantly lower nitric oxide metabolite concentrations in heart (0.32?±?0.07 vs. 0.90?±?0.14 nmol/mg protein, p?=?0.004) and aorta (2.98±0.56 vs. 6.15±0.74 nmol/mg protein, p?=?0.011) tissues. Nitrate therapy restored heart nitric oxide metabolite levels decreased by fetal hypothyroidism, while l-arginine administration further decreased aorta nitric oxide metabolite levels. Sodium nitrate increased and l-arginine decreased serum nitric oxide metabolite levels in both control and fetal hypothyroid animals. In conclusion, nitrate therapy restores decreased heart nitric oxide metabolite levels, whereas l-arginine decreases aorta nitric oxide metabolite levels even further in fetal hypothyroid rats, findings relevant to the cardiovascular consequences of congenital hypothyroidism in adulthood.  相似文献   
68.
Molecular Biology Reports - Cells translate the mechanosensing of extracellular matrix component dysregulation and stiffness into the signal transduction including Osteopontin (OPN) through the...  相似文献   
69.

Electrospray technique was applied to produce nanoparticles (NPs) from walnut protein isolate (WPI) in order to encapsulate curcumin. The optimized condition for the production of the WPI NPs was WPI concentration of 3.5%, a solvent mixture of deionized water: 2-propanol (2:1, v/v), electrospraying at a fixed distance, voltage and flow rate including 17.5 cm, 20 kV and 0.09 mL/h, respectively. The ratio of curcumin to WPI was 1:100 (w/w), and the encapsulation efficiency was around 61.5%. The addition of curcumin to WPI solution affected the size, form and surface properties of the electrosprayed NPs. FESEM, HRTEM, AFM, XRD, FT-IR and fluorescence spectroscopy, were applied for the characterization of the produced NPs via electrospraying. The in vitro study revealed that release of curcumin was limited in the stomach due to the protective effect of WPI NPs. In the small intestine, WPI particles were hydrolyzed and curcumin was released. Furthermore, the antioxidant activity of curcumin-WPI NPs after in vitro digestion was significantly higher than WPI NPs due to the bioactive peptides released from WPI NPs. It can be concluded that WPI NPs could act as a unique food-grade carrier to boost the solubility of curcumin.

  相似文献   
70.
International Journal of Peptide Research and Therapeutics - Recombinant reteplase is the truncated form of tissue plasminogen activator. Signal peptides play a pivotal role in the secretion of...  相似文献   
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