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101.
The anticonvulsant activities of Crocus sativus stigma constituents, safranal and crocin, were evaluated in mice using pentylenetetrazole (PTZ)-induced convulsions in mice. Safranal (0.15 and 0.35 ml/kg, i.p.) reduced the seizure duration, delayed the onset of tonic convulsions and protected mice from death. Crocin (200 mg/kg, i.p.) did not show anticonvulsant activity.  相似文献   
102.
103.
Background:Enhancing the therapeutic profile of hydrophobic drugs using the development of biocompatible drug delivery systems is an urgent need. Many types of research have been conducted on graphene derivatives owing to their unique characteristics. Methods:In this survey, QUER, a natural medicine, was loaded on carboxylated GO, and cytotoxicity assay and the uptake of QUER into prostate cancer cells (PC3) were evaluated.Results:The release behavior of QUER was temperature- and pH-sensitive. Although QUER was loaded with high efficiency, the released rate was low (23.25% at pH 5.5 and 42 °C). The toxicity and intensity of fluorescence in the FREE QUER were higher than the loaded form. Conclusion: High-capacity loading and controlled release of GO QUER can be recognized as a proper candidate in treating cancer.Key Words: Drug delivery systems, Graphene oxide, Nanoparticle, Quercetin  相似文献   
104.
The electrospinnability of aloe vera gel and the release mechanism as well as the kinetic of its release from poly vinyl alcohol (PVA) nanofibrous matrix is reported. Addition of PVA by an amount of only 1 % (w/w) to aloe vera solution made its electrospinning possible leading, to the fabrication of aloe vera nanofiber (99 %) with an average diameter of around 80 nm. Electrospinning of aloe vera-PVA solutions (25-75, 50-50, 75-25) led to the fabrication of nanofibers with average diameter of around 55, 105 and 110 nm, respectively. FTIR analysis showed no reaction between aloe vera and PVA. X-ray diffraction patterns showed no considerable effect from aloe vera on the amorphous structure of PVA. The release mechanism of aloe vera from PVA matrix in phosphate buffer solution was of Ficki type and the kinetic of the release followed Higuchi model. Aloe vera or aloe vera-PVA electrospun nanofibers may be used as an aloe vera release system in wound care. In a phosphate buffer solution, at least 60 percent of aloe vera is released in the first hour and about 90 % of aloe vera is released in 2-4 hours depending on the diameter of the nanofibers.  相似文献   
105.

Insulin-like growth factor-binding protein acid-labile subunit (IGFALS) encodes a protein which binds to IGF1 and IGFBP-3 to regulate the growth, differentiation, and other physiological processes. The aim of this study was the identification of allelic polymorphisms of the IGFALS gene using the PCR-RFLP technique and evaluation of their association with growth traits. For this end, 120 blood samples were randomly collected from each breed. Following amplification of an 1113-bp fragment of exon 1 and a part of intron 1 of the IGFLAS gene, genotyping was conducted by three restriction enzymes including HinfI, MscI, and PvuII. The results showed that only one allele was observed in IGFALS-PvuII site, while in IGFLAS-MscI site, three AA, AB, and BB genotypes with the frequencies of 17.5%, 32%, and 50.5% and 11%, 37.5%, and 51.5% were observed in Makouei and Ghezel sheep breeds, respectively. Additionally, in the IGFLAS-HinfI site, two AB and BB genotypes with the frequency of 34.2% and 65.8% were observed in Makouei sheep and AA, AB, and BB genotypes with the frequency of 9%, 21%, and 70% were observed in Ghezel sheep. So that, Makouei sheep with AB genotype had more chest girth (CG) compared with other genotypes. Furthermore, a significant association was observed between the genotypes of IGFLAS-HinfI with birth weight (BW) in Ghezel and BW, weaning weight (BW3), and CG in Makouei sheep. Haplotype analysis revealed an association between paternal haplotypes and BW in both Ghezel and Makouei breeds. So that, AAB and ABB haplotypes showed more BW than others in Makouei and Ghezel sheep, respectively.

  相似文献   
106.
In order to study the function of blast resistance gene and estimate resistance scale to Pyricularia grisea Sacc., the cause of Rice Blast Disease in rice, we evaluated 58 rice genotypes for phenotypic and molecular assessment. Phenotypic tests were conducted in a blast upland nursery and also in the greenhouse by using specific races of blast IA-82 and IA-90 in the greenhouse and local races for the nursery. The traits assessed consisted of infection type (IT), percent diseased leaf area (DLA) (in both nursery and greenhouse), and lesion number (LN), lesion size (LS, mm2) only in greenhouse conditions. Molecular assessment was done by using three STS, JJ80, JJ81, and JJ113, and four microsatellite markers, RM224, RM277, RM463, and RM179 which are linked to resistance genes on rice chromosomes. Genotypes had different reactions against blast races in the phenotypic part of experiment. Consequently, all genotypes were divided into three groups with high, intermediate, and susceptible resistance. Our results indicated that partial resistant genotypes are preferable for achieving durable control. Eventually, the association test between molecular data and phenotypic results showed that there is a significant level for some of the SSR markers. This means there is at least one race-specific resistance gene in the genetic sources of these genotypes that bring about resistance functions to the blast races. These results demonstrated the existence of functional resistance genes in Iranian rice genotypes. Thus, these functional genes are responsible for some parts of resistance that have been measured in phenotypic tests. Our results could be useful for breeding programs to make some modifications in the rice germplasm and would also be applicable for the marker-assisted selection process.  相似文献   
107.
ABSTRACT

Meat products, such as fish meat, are known to be susceptible to undesirable chemical and microbial reactions that characterize spoilage. In this study, the effect of a sodium alginate and chitosan coating incorporated with Mentha piperita, Artemisia dracunculus, and Zataria multiflora essential oils on chemical and microbial attributes of rainbow trout meat was evaluated during storage at 4°C. Chemical and microbial assays were performed on rainbow trout fillets with alginate and chitosan coatings and 0.2% concentration of test essential oils. The results showed that the alginate coating with essential oils significantly decreased production of thiobarbituric acid (TBA) and total volatile basic nitrogen (TVBN) and reduced the growth of foodborne spoilage bacteria during storage at 4ºC. At day 12, the best results were obtained in chitosan coating + Z. multiflora, with 5.96 ± 0.12, 4.93 ± 0.12, and 3.83 ± 0.2 for total viable counts, psychrotrophic bacterial count, and lactic acid bacteria count, respectively. Moreover, the lowest amounts of chemical analysis were observed in chitosan coating + Z. multiflora at the final day (0.54 ± 0.03 and 20.31 ± 0.1 for TBA and TVBN, respectively). Our study revealed that essential oils can be used as effective natural components against undesirable chemical and microbial reactions in fish meat.  相似文献   
108.
Abstract

In the present study, the green synthesis of Zn and Cu nanoparticles (NPs) was carried out via Zn and Cu ions reduction during their exposure to basil extract. The shape, size and chemical identity of the Zn and Cu NPs were determined using SEM and XRD analysis. To investigate the effects of the Zn and Cu NPs on the morphological and biochemical traits of basil plant, an experiment was conducted as a factorial based on completely randomized design with 4 levels of Zn NPs (0, 1000, 2000, and 4000?ppm) and 4 levels of Cu NPs (0, 1000, 2000, and 4000?ppm). Based on the results, nutrient treatments, especially 4000?ppm Zn NPs + 2000?ppm Cu NPs caused a significant increase in most morphological parameters. The application of the Zn and Cu NPs significantly affected concentrations of chlorophyll a, chlorophyll b, total chlorophyll and carotenoid in the leaves of basil plants. The highest total phenolic and flavonoid content was obtained for 4000?ppm Zn NPs + 2000?ppm Cu NPs treatment. Plants treated with 4000?ppm Zn NPs + 0?ppm Cu NPs showed the highest antioxidant activity followed by 4000?ppm Zn NPs + 2000?ppm Cu NPs and 2000?ppm Zn NPs + 0?ppm Cu NPs. It can be concluded that foliar application of the Zn and Cu NPs is necessary for obtaining better quantity and quality in basil.  相似文献   
109.

Background:

Apolipoprotein A2 (APOA2) is the second major apolipoprotein of the high-density lipoprotein cholesterol (HDL-C). The study aim was to identify APOA2 gene variation in individuals within two extreme tails of HDL-C levels and its relationship with HDL-C level.

Methods:

This cross-sectional survey was conducted on participants from Tehran Glucose and Lipid Study (TLGS) at Research Institute for Endocrine Sciences, Tehran, Iran from April 2012 to February 2013. In total, 79 individuals with extreme low HDL-C levels (≤5th percentile for age and gender) and 63 individuals with extreme high HDL-C levels (≥95th percentile for age and gender) were selected. Variants were identified using DNA amplification and direct sequencing.

Results:

Screen of all exons and the core promoter region of APOA2 gene identified nine single nucleotide substitutions and one microsatellite; five of which were known and four were new variants. Of these nine variants, two were common tag single nucleotide polymorphisms (SNPs) and seven were rare SNPs. Both exonic substitutions were missense mutations and caused an amino acid change. There was a significant association between the new missense mutation (variant Chr.1:16119226, Ala98Pro) and HDL-C level.

Conclusion:

None of two common tag SNPs of rs6413453 and rs5082 contributes to the HDL-C trait in Iranian population, but a new missense mutation in APOA2 in our population has a significant association with HDL-C.  相似文献   
110.
Set marks are fabric defects in weft direction which are caused by an interruption of the weaving process. In this study, based on one-quarter fractional factorial design, among eight parameters of weaving machine, i.e. horizontal and vertical position of back rest roller, horizontal position of warp stop motion, shed crossing degree, shed crossing point position, warp tension, stoppage position of machine, and stoppage time, four most effective parameters was determined. These parameters were stoppage position of machine, vertical position of back rest roller, shed crossing point, and horizontal position of warp stop motion. Then using full factorial design effectiveness of these parameters was evaluated statistically at 99 % confidence level and effect of them on set mark studied in detail. Statistical evaluations showed that the stoppage position of machine was the most effective parameters on intensity of set mark of multifilament polyester fabric. A specific image capturing device for using on weaving machine based on CCD camera was designed. Image processing technique was used to measure the pickspacing in stop zone objectively. Five picks before and five picks after stoppage was considered as stop zone and the standard deviation of pickspacing was used as a criterion which interpret this defect. Dynamic loading of warp yarns were execute to evaluate the relaxation behavior of polyester multifilament warp yarns.  相似文献   
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