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151.
Background:CTX is a rare congenital lipid-storage disorder, leading to a progressive multisystem disease. CTX with autosomal recessive inheritance is caused by a defect in the CYP27A1 gene. Chronic diarrhea, tendon xanthomas, neurologic impairment, and bilateral cataracts are common symptoms of the disease. Methods:Three affected siblings with an initial diagnosis of non-syndromic intellectual disability were recruited for further molecular investigations. To identify the possible genetic cause(s), WES was performed on the proband. Sanger sequencing was applied to confirm the final variant. The clinical and molecular genetic features of the three siblings from the new CTX family and other patients with the same mutations, as previously reported, were analyzed. The CYP27A1 gene was also studied for the number of pathogenic variants and their location. Results:We found a homozygous splicing mutation, NM_000784: exon6: c.1184+1G>A, in CYP27A1 gene, which was confirmed by Sanger sequencing. Among the detected pathogenic variants, the splice site mutation had the highest prevalence, and the mutations were mostly found in exon 4. Conclusion:This study is the first to report the c.1184+1G>A mutation in Iran. Our findings highlight the other feature of the disease, which is the lack of relationship between phenotype and genotype. Due to nonspecific symptoms and delay in diagnosis, CYP27A1 genetic analysis should be the definitive method for CTX diagnosis. Key Words: Cerebrotendinous xanthomatosis, CYP27A1, Intellectual disability, Iran, Whole exome sequencing  相似文献   
152.
Characterization and extraction of plant secondary metabolites are important in agriculture, pharmaceutical, and food industry. In this regard, the applied analytical methods are mostly costly and time-consuming; therefore, choosing a suitable approach is essential for optimum results and economic suitability. One of the recently considered methods used to characterize new types of materials is MIPs. Among the various applications of MIPs is the identification and separation of various plant-derived compounds, such as secondary metabolites, chemical residues, and pesticides. The present review describes the application of MIPs as a tool in medicinal plant material analysis, focusing on plant secondary metabolism. Key Words: Molecularly imprinted polymers, Plants medicinal, Secondary metabolism  相似文献   
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Genetic Resources and Crop Evolution - Lodging is one of the most important factors that affect wheat final yield. Emmer [Triticum turgidum subsp. dicoccum (Schrank ex Schübl.) Thell.] is a...  相似文献   
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Asparagus officinalis is the most economically important species of asparagus worldwide. Commercial cultivars of asparagus are susceptible to some biotic and abiotic stresses. Drought stress is one of the most common stresses in agricultural crops cultivation. The main purpose of the current study was to compare Iranian asparagus accessions drought tolerance rate with that of ‘Mary Washington’ commercial cultivar and introducing superior accessions in terms of dry resistance rate. A factorial experiment was laid out based on a completely randomized design with three replications. The factors were a) asparagus accession in 10 levels including nine wild accessions of Iranian asparagus and ‘Mary Washington’ commercial cultivar (as control) and b) drought stress in four levels including 0 (as control), 5, 10 and 15% (w/v polyethylene glycol). Results showed that highest values of percentage and speed of seed germination and lengths of radicle and plumule were recorded in Gazanak accession. The lowest values of radicle length were recorded in Chalaki and Shiraz accessions (6.19 and 8.01?mm, respectively). Calli of ‘Mary Washington’ cultivar under highest applied level of drought stress showed the lowest value of relative growth rate (11.53?mg/day). Cluster analysis based on assessed characteristics under different applied levels of drought stress, divided Iranian asparagus accessions into four groups at Euclidean distance of 2.0. In conclusion, obtained results showed that Iranian asparagus accessions especially Gazanak accession could be a good candidate to apply in asparagus breeding programs with aim of producing asparagus dry tolerant cultivars.

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157.
Evaluating agricultural loss due to flooding is essential for defining an appropriate risk level in flood management projects. This research introduces a method for computing annual damage risk for rice fields with respect to both spatial and temporal pattern of floods, while considering the effect of crop growth stages on the total damage. For finding the spatial pattern of floods, HEC-RAS was employed to derive selected physical parameters of floods of interest and then a physical loss function was used to calculate the unconditional loss over flood prone areas. A time-dependent loss function was introduced for rice to determine the effect of growth on damages derived through the physical loss function. Due to the seasonal nature of agricultural risk, frequency analysis was performed for seasonal discharges for each growth stage of rice. A method was introduced to use the concept of Expected Annual Damage in agricultural fields. A method called “AGEAD” was introduced for evaluating short-term risk for agricultural activities considering their inherent spatial and temporal characteristics. Results showed that damages evaluated by employing AGEAD were completely different from what was obtained by applying a flood of defined return period, i.e. from the results of long-term risk evaluation. While it is common to attribute a unique predicted loss to all flood prone areas, AGEAD application showed that different zones in flooded paddy fields were subjected to different amount of damages from 100 to 0%.  相似文献   
158.
This study was carried out to investigate the effect of water‐soluble polysaccharides extract of algae Ulva rigida (WPU) as dietary supplement on growth performance, antioxidant enzyme activity, lysozyme and phenoloxidase activity, and resistance of shrimp (Litopenaeus vannamei) subjected to bacterial infection with Photobacterium damselae. Three replicate groups of shrimp (1.0 g) were fed four diets containing four levels, 0 or control, 0.5, 1 and 1.5 g/kg of WPU for 8 weeks over the growth trial. Thereafter, 30 shrimps from each dietary treatment were infected with bacteria P. damselae to evaluate disease resistance of infected shrimp. The results of this study showed that WPU was effective as a growth promoter for L. vannamei. The best growth rate was observed in shrimp fed 1.5 g/kg of WPU diet. Regarding antioxidant defences, the diets supplemented with three levels of WPU stimulated glutathione peroxidase and catalase activates in experimental shrimps. MDA content of L. vannamei‐fed diet containing WPU 1.5 and WPU 1.0 was lower than WPU 0 and WPU 0. 5 diets. Also, lysozyme and phenoloxidase activities of shrimp receiving WPU at 1.0 and 1.5 level were significantly higher than those fed WPU 0 and WPU 0.5 diets. In addition, using WPU extract in all diets decreased mortality in L. vannamei in a dose‐dependent manner after challenge with P. damselae. These results suggest that incorporation of water‐soluble polysaccharides from green algae U. rigida at 1.5 g/kg doses improves growth and antioxidant activity and enhances the immune responses in shrimp L. vannamei.  相似文献   
159.
High-quality wood resource scarcity as well as population growth and demand of wood have encouraged the use of alternative sources of lignocellulosic materials. In this study, the possibility of producing particleboard from waste cotton stalks is evaluated. The effects of the independent variables included weight ratio of melamine-formaldehyde to urea-formaldehyde, shelling ratio and the percentage of cotton stalks to poplar in the core layer were analyzed in the form of response surface methodology based on second-order multiple linear regression model. The results showed that there was perfect agreement between the estimated values and observed data, as with an increase in the ratio of melamine-formaldehyde resin to urea-formaldehyde, shelling ration and amount of poplar in the core layer of panels, modulus of rupture, modulus of elasticity and internal bonding increase. The optimal point of use of investigated variables included 18.30% melamine-formaldehyde, 30.35% thickness of the surface layers and 10.70% of poplar in the core layer.  相似文献   
160.
Present study investigates the effect of salinity stress on physiological and biochemical characteristics of two maize genotypes cultivated under controlled growth conditions. The selected maize genotypes being salt-tolerant and salt-sensitive were respectively designated as Sahwal-2002 and Sadaf. The experiment was conducted in triplicates, two varieties, three priming treatments and two salinity levels, in the Government College University, Faisalabad. The antioxidants activity was measured by comparing the tolerance in response to acute and prolonged salinity treatment. The difference of genotype with salinity tolerance as well as seed priming with phenylalanine were not dependent on antioxidant activity when salt exposure was prolonged. The results show that an indirect relationship was present for PAL seed priming and oxidative damage due to salt. The antioxidant enzymes present in plant effectively reduced the oxidative damage of salt and thus, increased the overall crop yield.  相似文献   
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