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Intestinal histology and stereology in rainbow trout (Oncorhynchus mykiss) administrated with nanochitosan/zeolite and chitosan/zeolite composites 
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下载免费PDF全文 Gholamreza Hamidian Khadijeh Zirak Najmeh Sheikhzadeh Ali Khani Oushani Sadigheh Shabanzadeh Baharak Divband 《Aquaculture Research》2018,49(5):1803-1815
In previous study, the effects of synthesized chitosan/zeolite and nanochitosan/zeolite composites on rainbow trout growth, digestive enzyme activities and some biochemical parameters were shown. In this study, the effects of experimental diets based on the previous study on the rainbow trout intestinal histology and stereology were assessed: control diet (no zeolite and composite), T1 diet (14.28 g/kg zeolite), T2 diet (0.05 g/kg chitosan included in zeolite), T3 diet (0.5 g/kg chitosan included in zeolite), T4 diet (5 g/kg chitosan included in zeolite), T5 diet (0.05 g/kg nanochitosan included in zeolite), T6 diet (0.5 g/kg nanochitosan included in zeolite), T7 diet (5 g/kg nanochitosan included in zeolite). The experiment was conducted for 60 days. Results showed that supplemental diets did not have side effect on the normal structure of intestinal segments but administration of T1 and T4 diets had slight negative effects on structural maintenance in the middle part of intestine. Acidic mucin producing goblet cell percentage was also higher in nanocomposites‐administrated groups in comparison with the control group. Enhanced villus height, density and finally absorption surface area in different parts of rainbow trout intestine were mainly shown in T7 group. Meanwhile, higher thickness of tunica mascularis in different regions were noted in treatment groups especially in T7 group. The number of intraepithelial mononuclear leukocytes in fish intestine received treatment diets was also higher than control group. In conclusion, nanochitosan/zeolite composites in comparison with zeolite and chitosan/zeolite composites were more effective to improve histological structure of rainbow trout intestine. 相似文献
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Variability of Available Cadmium in Relation to Soil Properties and Landuse in an Arid Region in Central Iran 总被引：1，自引：0，他引：1
Due to potential problems associated with their toxicities, concentration of heavy metals in soils is of great environmental concern. To evaluate Cd content, its spatial pattern, and availability in the surface soils of agricultural, industrial and urban regions of Isfahan, central Iran, we collected 255 topsoil samples (0–20 cm) from the nodes of an irregular grid in a study area of 6800 km2. In the soil samples we measured total and DTPA-extractable Cd concentrations, soil pH, organic mater (OM), clay content, soil salinity, and chloride concentration. The total Cd concentration in 90% of the samples exceeded the suggested Swiss thresholds of 0.8 mg kg?1. Landuse had a significant effect on total concentration of Cd in the soil but had no effect on DTPA-extractable Cd. High values of total Cd were found in industrial and urban areas whereas low values occurred in uncultivated lands. The correlation analysis revealed that soil salinity alone explained 36% of the Cd variation in the entire study area. The correlation was particularly strong in uncultivated areas (R 2 = 0.70). Spatial analysis of available Cd using indicator kriging and soil salinity showed a spatial co-occurrence of these two variables. 相似文献
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Khadijeh Alijani Mohammad Jafar Bahrani 《Archives of Agronomy and Soil Science》2013,59(14):1984-1997
ABSTRACTConservation tillage practices have gained interests. A 2-year field study (2014–2015) was conducted to evaluate four N rates (0, 69, 138, and 207 kg N ha?1) effects on irrigated sweet corn (Zea mays L.) grown with or without wheat (Triticum aestivum L.) residue removal and conventional (CT), reduced (RT), or no-tillage (NT) practices near Shiraz, Iran. After 2 years, maximum marketable yield occurred at 156 and 159 kg N ha?1 under CT and NT, respectively, while yield was tended to be increased with increasing N rates under RT. Increasing N rate increased total plant N uptake, shoot, and grain N accumulation. The lowest nitrogen use efficiency (NUE) was obtained under NT, while RT and CT either showed similar effects or RT was superior over CT. Soil total N was greater under CT and residue retention showed 18% and 14% higher N concentration than residue removal in 2014 and 2015, respectively. Soil organic matter was the highest (2.59%) under RT with residue retention and 138 kg N ha?1. Conservation tillage needs more N rather than CT during transition from conventional to conservation agriculture practices, but it is based on the short-term results and evaluation of long-term experiment is highly recommended. 相似文献
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Samaneh Rahamooz-Haghighi Khadijeh Bagheri Hossein Danafar Ali Sharafi 《Iranian Biomedical Journal》2021,25(2):106
Background:To study the anticancer activity of Plantago major, we assessed the effect of ethanolic, methanolic and acetonic extracts of this plant on HCT-116, SW-480, and HEK-293 cell lines as control. Methods:The cytotoxic activity, biocompatibility, and toxicity were evaluated by MTT assay, hemolysis, and Artemia salina-LD50 (on mice) tests, respectively. The analysis of the extracts was performed by GC-MS analysis. Results:The results showed that all the extracts had the most antiproliferative properties on the HCT-116 cell line. The P. major root extract was more effective than the aerial parts, and IC50 values for ethanolic, methanolic and acetonic root extracts were 405.59, 470.16, and 82.26 µg/mL, respectively on HCT-116 cell line at 72 h. Hemolysis degree of the ethanolic extract of aerial and root parts were approximately 1% at 400 μg/mL.. Using the ethanolic extracts, the Artemia survived every concentration, and no toxicity was observed. One week after the oral administration of different parts of P. major extracts, none of the mice died, even those were administered 2000 mg/kg. The results of GC/MS analysis showed that P. major extracts contain potential anticancer compounds, such as stearic acid (8.61%) in aerial parts of methanolic extract and 1,2- Benzenedicarboxylic acid, mono(2-ethylhexyl)ester (88.07% and 40.63%) in aerial and root parts of acetonic extract of P. major. Conclusions:Our findings suggest that the P. major is a source of potential compounds with antiproliferative properties. Key Words: Gas chromatography-mass spectrometry, HCT-116 cells, Hemolysis, Lethal dose 50 相似文献
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Hamid Abbasdokht Mohammad Reza Chaichi Sadegh Asadi Mehran Manafi Noran Hamid Reza Khademi 《Archives of Agronomy and Soil Science》2016,62(12):1741-1752
In order to investigate the effects of nitrogenous fertilizers (biological, chemical, integrative) on quantity and quality of forage-medicine in the additive intercropping of sorghum with fenugreek, an experiment was performed in two agronomic years 2010–2011 and 2011–2012 in the Research Farm of Agricultural Faculty of Tehran University located in Dolatabad, Karaj, as split-plot in the form of randomized complete block design (RCBD) with three replications. The main treatments consisted of the control or without fertilizer (N0), biofertilizer (Nbi) (Azotobacter, Rhizobium, Azospirillum, mycorrhiza), chemical nitrogen fertilizer (Nch 100) and integrative fertilizer including biofertilizer plus 50% chemical nitrogen fertilizer (Nbi + Nch50). The subtreatments included sole cultivation of fenugreek without weeds (T0), sole cultivation of fenugreek with weeds (Tw), sole cultivation of sorghum without weeds (S0), sole cultivation of sorghum with weeds (Sw), cultivation of sorghum + 50% fenugreek (ST50) and cultivation of sorghum + 100% fenugreek (ST100). Based on the results, the highest effective extract of fenugreek (trigonelline) and fenugreek dry matter was gained through the application of biological fertilizer + the sole fenugreek treatment (no weeds). Moreover, the highest sorghum dry mater was yielded by the use of the integrative fertilizer + the sole sorghum (no weeds) treatment; however, the highest total dry matter was observed to be more in the mixed treatment of integrative fertilizer and sorghum + 50% fenugreek. The lowest weed biomass was also linked to the integrative treatment biological fertilizer and sorghum + 100% fenugreek. 相似文献
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A. Jafari P. A. Finke J. Vande Wauw S. Ayoubi H. Khademi 《European Journal of Soil Science》2012,63(2):284-298
The main objectives of this study were to compare binary logistic regression as an indirect approach and multinomial logistic regression as a direct approach to produce soil class maps in the Zarand region of southeast Iran. With indirect prediction, the occurrence of relevant diagnostic horizons was first mapped, and subsequently, various maps were combined for a pixel‐wise classification by combining the presence or absence of diagnostic horizons. In direct prediction, the dependent variable was the great group itself, so the probability distribution of the great soil groups was directly predicted. Among the predictors, the geomorphology map was identified as an important tool for digital soil mapping approaches as it helped to increase the accuracy. The results of prediction showed larger mean probability values for each great soil group in the areas actually covered by the great soil groups compared with other areas, indicating the reliability of the prediction. In most predictions, the global purity was slightly better than the actual purity for the models; however, both models provided poor predictions for Haplocambids and Calcigypsids. The results showed that soils with better prediction were those much influenced by topographical and geomorphological characteristics and soils with very poor accuracy of prediction were only slightly influenced by topographical and geomorphological characteristics. An advantage of the indirect method is that it gives insight into the causes of errors in prediction at the scale of diagnostic horizons, which helps in the selection of better covariates. 相似文献
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Khadijeh Alijani Seyed Abdolreza Kazemeini Mohammad Jafar Bahrani Hossein Ghadiri 《Weed Biology and Management》2023,23(1):3-13
Soil weed seed bank is an important factor determining above-ground floristic composition and weed density in agricultural systems. The quantitative and qualitative measures of weed seed bank can help growers to predict the extent to which they are facing weed problems. Along with tillage, crop residues can affect the fate of weeds in the upcoming crops. To investigate such effects, we compared the effects of tillage systems [conventional tillage (CT), reduced tillage (RT), and no tillage (NT)], wheat residue retention, and nitrogen (N) rates (0, 69, 138, and 207 kg N ha−1) on depth-related characteristics of the weed seed bank under a sweet corn-wheat sequence during 2014–2015 growing seasons in Shiraz, Iran. Soil bank was not affected by tillage systems but tended to be slightly higher under RT. The highest (898 seeds m−2) and lowest (322 seeds m−2) weed population at 0–10 cm depth were found when 138 kg N ha−1 in 2015 and 207 kg N ha−1 in 2014 were applied. Species richness and diversity were higher under NT and RT practices at the top layer, but CT system was more diversified at deeper depths. They were higher when crop residues were retained as well. Barnyard grass (Echinochloa crus-galli [L.] Beauv), common lambsquarter (Chenopodium album L.), common purslane (Portulaca oleracea L.), field bindweed (Convolvulus arvensis L.), flixweed (Descoreinia sofia [L.] Webb. & Berth.), henbit (Lamium amplexicaule L.), pigweeds (Amaranthus spp.), and stinking goosefoot (Chenopodium vulvaria L.) were the most common weeds found in all tillage systems and soil depths. Grasses were relatively lower than broadleaves regardless of treatments. Weed seed bank was mostly affected by weather conditions than treatments in this short-term experiment. 相似文献
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Atmospheric nitrogen fixation as a result of the symbiosis between bacteria and legume species, can result in major advantages in providing host plants with organic nitrogen. The objective of the present study was to evaluate the physiological potential during early seedling development for initiation of nodulation and nitrogen fixation activity of four grain legumes species: soybean [Glycine max (L.)], cowpea [Vigna unguiculate (L.) Walp], common bean [Phaseolus vulgaris (L.)], and peanut [Arachis hypogaea (L.)]. Seedlings were grown on a hydroponic solution so that nodule development could be readily observed until about 3 weeks after germination. Nodules developed in all cases. Acetylene reduction activity (ARA) by soybean and cowpea was also found early in seedling development. In contrast, peanut and common bean showed little or no development of ARA during seedling development. The results provided insight into differences in physiological potential among grain legumes in establishing symbiotic nitrogen fixation during crop establishment. These results indicate those species/cultivars that are candidates for readily establishing nitrogen fixation activity during the seedling stage of plant development. 相似文献