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141.
Mohammad Javad Nazarideljou Masoud Haghshenas Hamideh Jaberian Hamedan Antonio Ferrante 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(2):105-113
Optimisation of the mineral composition of the nutrient solution is one of the most important factors affecting crop productivity and quality under hydroponic cultivation. Considering the role of minerals in nutrition and the lack of studies on the K+:Ca++ ratio of nutrient solution on fruit quality, a study was carried out to evaluate the effects of K+:Ca++ ratios on growth, yield, vitamin C content of the fruit and total carbohydrate and phenolic compounds of the ‘Paros’ strawberry under hydroponic conditions. The highest total phenolic compounds, photosynthetic capacity, including leaf area, photosynthetic pigments, stomatal conductance and yield were observed at the 1.4 ratio (K > Ca). Enzymatic (peroxidase, superoxide dismutase and catalase) and non-enzymatic (total phenol, phenolic compounds and anthocyanin) antioxidant capacities were affected significantly by the K+:Ca++ ratio. The highest antioxidant capacity was observed in ratios with K > Ca in the solution. We recommend growers to maintain an appropriate K+:Ca++ ratio in the nutrient solution, as this affects growth parameters, productivity and strawberry quality. 相似文献
142.
Evaluation of common bean lines for their reaction to tomato yellow leaf curl virus-Ir2 总被引：1，自引：0，他引：1
Tomato yellow leaf curl virus (TYLCV) can cause an economically relevant disease in the major tomato growing regions, and no resistance has been identified in commercial and wild tomato cultivars in Iran. In the present study, 34 common bean lines were screened for their reaction to TYLCV-Ir2 under greenhouse conditions. The experiment was conducted in a randomized complete block design with three replications. Bean plants were inoculated at the first trifoliate stage with viruliferous whiteflies (Bemisia tabaci biotype B) and were then sprayed with an insecticide and maintained in whitefly-proof greenhouse. The inoculated plants were monitored for the development of symptoms and the presence of viral DNA by polymerase chain reaction (PCR) four weeks after inoculation. Results revealed that out of the 34 lines, five were resistant. These lines exhibited either no symptoms or very mild symptoms and no viral DNA was detected in them by PCR. Two lines, which showed no typical disease symptoms but contained viral DNA, were identified as tolerant to TYLCV-Ir2. The vector feeding preference for common bean lines was assessed. Results indicated a significant difference in adult whitefly numbers among bean lines but there was no relationship between the number of whiteflies and disease symptom severity. The resistance to TYLCY-Ir2 expressed in common bean lines may be useful as source of resistance for the development of resistant commercial common bean cultivars. 相似文献
143.
Two experiments were conducted to evaluate the efficacy of clove solution on anesthesia and hematological parameters in Beluga,
Huso huso (L.). In the experiment 1, fish were exposed to concentrations of 300, 500, 700, 1,800 and 3,000 ppm clove solution and induction
(stage 3 and 4) as well as recovery period lengths were recorded. These concentrations were led to induction and recovery
time between 42–365 and 125–235 s, respectively, in dose-dependent manner. There was negative correlation between induction
and recovery time (R
2 = 0.92). In the experiment 2, fish were exposed to each aforementioned concentrations and let to reach stage 4 anesthesia
and then blood-sampled. Control group was sampled without anesthesia. Hematological studies between groups showed no significant
changes in white blood cell (WBC) and differential leukocyte count (P > 0.05). Hematocrit (Hct), hemoglobin (Hb), red blood cell (RBC) and mean corpuscular hemoglobin concentration levels were
significantly high in concentrations of 300–700 ppm compared to control, 1,800 and 3,000 ppm. Control and 500–3,000 ppm groups
have similar mean corpuscular volume values and significantly higher than 300 ppm. Lower values of mean corpuscular hemoglobin
were related to control, 3,000 and 1,800 ppm and higher values were observed in the others. Strong positive correlation were
observed between induction periods and Hct, Hb and RBC levels (R
2 = 0.095, 0.99 and 0.92, respectively). Results suggested that anesthesia with low concentrations of clove solution over a
long period is stressful compared to high concentrations over short period. 相似文献
144.
145.
Seyyed Mehdi Hosseinifard Asieh Ahmadpour Bagher Mojazi Amiri Majid Razeghi Mansour Arezo Ebrahimpour 《Fish physiology and biochemistry》2013,39(6):1505-1511
The main indication of cimetidine is being H2-receptor antagonist, but studies suggest that cimetidine may also act as a non-specific stimulant of cell-mediated immunity and immunomodulator. In order to determine the immunomodulatory effect of dietary intake of cimetidine in the common carp (100 ± 10 g), subjects were fed diets containing 0 (control), 50, 100 and 200 mg cimetidine kg?1 of dry diet for a period of 6 weeks. TLC and NBT assays were significantly (P < 0.05) stimulated in cimetidine-supplemented groups displaying the highest value in 200 mg kg?1 group. A decrease (P < 0.05) in cortisol and ACH50 value was recorded in fish treated with cimetidine. Serum protein, albumin and serum globulin levels were not significantly changed. The findings of the present investigation suggest that the incorporation of cimetidine in the diet of common carp enhances the non-specific immunity. 相似文献
146.
Aryamanesh S Ebrahimi SM Abotaleb N Nobakht M Rahimi-Moghaddam P 《Iranian Biomedical Journal》2012,16(1):44-51
Background: Antioxidants such as α-tocopherol (vitamin E) and β-carotene (vitamin A) play an important role in protective effect of repeated brief periods of ischemia, namely ischemic preconditioning (IPC). Values of these antioxidants were investigated and compared after induction of ischemia reperfusion (IR) and kidney IPC in both male and female rats. Methods: Forty eight Wistar rats were divided randomly into six groups of 8: groups A and B (male and female controls, respectively), group C (male IR or IR cases), group D (female IR cases) and groups E and F (male and female IPC cases, respectively). In groups C and D, ischemia was induced by clamping of left renal arteries for 45 min. In groups E and F, rats underwent four cycles of 4 min of arterial clamping and 11 min of de-clamping before final 45 min ischemia induction. Afterward, serum was collected to assess the blood urea nitrogen, creatinine and vitamins E and A values. Renal tissues were obtained for histological assessments. Results: α-tocopherol levels in male and female rats showed a significant increase in IPC compared with IR group (P<0.01) and also in female IPC compared with male IPC group. β-carotene levels had no significant variations. Histological evaluation showed that IR-induced renal injuries were less in female rats. Also, protective effects of IPC were more in female rats (P<0.01). Conclusions: Renal IPC reduced damages in both male and female rats, but tissue injuries in females were decreased much more along with the increase of endogenous vitamin E. Key Words: α-tocopherol, β-carotene, Antioxidant, Reperfusion, Ischemic preconditioning (IPC) 相似文献
147.
Mohammad Javad Mehdipour Moghaddam Adeleh Alsadat Mirbagheri Zivar Salehi Seyyed Mahmood Habibzade 《Iranian Biomedical Journal》2015,19(4):233-239
Background:
Extended spectrum beta lactamases (ESBLs) are an important cause of transferable multidrug resistance (MDR) in gram-negative bacteria. The most described ESBL genes are generally found within integron-like structures as mobile genetic elements. The aim of this study was to identify the accompanying of class 1 integrons and ESBLs in the MDR E. coli isolates.Methods:
Susceptibility to antimicrobial agents was determined for 33 E. coli strains by the disk diffusion method. Double-disk synergy test was applied for screening ESBL. To identify the strains carrying integrons, the conserved regions of integron-encoded integrase gene intI1 were amplified. For detection of gene cassettes, 5′CS and 3′CS primers were used.Results:
All E. coli isolates were identified as multi-drug resistant. More than 50% of the isolates were resistant to tetracycline, cephalothin, cefuroxime, amoxicillin-clavulanic acid, and third generation cephalosporines. Nearly all of the isolates displayed sensitivity to piperacillin. There was a significant correlation between production of ESBL and resistance to all antibiotics except for ciprofloxacin and piperacillin (P < 0.01). Thirty two MDR strains (97%) included class 1 integron, and some isolates that included integrons were similar in the size of gene cassettes. The isolates were different in the resistance profiles; however, some others had similar resistance profiles. Of eight ESBL positive isolates, seven (87.5%) carried class 1 integrons.Conclusion:
Class 1 integrons were frequent in MDR and also ESBL-producing E. coli isolates. High prevalence of class 1 integrons confirms that integron-mediated antimicrobial gene cassettes are important in E. coli resistance profile. Key Words: Antibiotic, Integrons, Escherichia coli 相似文献148.
Morteza Yousefi Mehdi Paktinat Nemat Mahmoudi Amalia Pérez-Jiménez Seyyed Morteza Hoseini 《Fish physiology and biochemistry》2016,42(5):1417-1425
The aim of the present study was to investigate whether supplementary nucleotide “Optimun” mitigates the adverse effects of chronic overcrowding in Oncorhynchus mykiss. Two experimental diets [control and nucleotide-supplemented (0.2 %)] and two rearing densities (10 and 30 kg m?3) were combined to have four experimental treatments. The fish were reared for 45 days under different densities using different diets. At the end of the trial, FCR of the fish in higher density was significantly higher than those of the lower density. Nucleotide had no significant effects on growth performance and survival rate. Supplemented nucleotide significantly increased blood hematocrit, whereas it decreased serum total protein, total immunoglobulin (Ig) and creatinine. Overcrowding significantly increased serum glucose and total protein level and decreased serum lysozyme activity, but supplemented nucleotide produced no improvement in these items. No significant effect of overcrowding and dietary nucleotide was observed on serum cortisol. Supplemented nucleotide significantly increased serum urea under low stocking density. Overall, the results showed that 0.2 % “Optimun” had no positive effects on rainbow trout and also caused some immunological and metabolic problems. These findings are not in accordance with those obtained in the same species, with same nucleotide source and level, but acute stress; thus, further studies are encouraged on this topic. 相似文献
149.
Taghi T. Bazargani DVM MSc Saman Rafia DVM Javad Ashrafi Helan DVM PhD Seyyed H. Moaddab DVM 《Journal of Equine Veterinary Science》2010,30(12):711-714
An 8-year-old Thoroughbred Turkoman crossbred mare was examined for right pelvic limb paresis and ataxia. The signs had been progressing through time. Neurological examinations revealed a gait deficit, right pelvic limb gluteal muscles atrophy, skin hypalgesia around the tail, perineum, and right pelvis. Hyperesthesia was found in the margins of anesthetic areas. Hypotonic anal sphincter and flaccid tail were also evident. Fecal and urinary retention were revealed by rectal palpation. At necropsy, the affected nerve roots in right lumbar, sacral vertebrae, as well as cauda equina were found to be significantly thickened and fibrotic with adhesions to the related vertebral bodies. Histopathological examinations confirmed the diagnosis of polyneuritis in this mare. 相似文献
150.
Seyyed Hamid Reza Ramazani 《Journal of Crop Science and Biotechnology》2016,19(4):303-309
To determine the most important traits influencing seed yield of sesame, 18 lines were evaluated in a randomized block design with three replicates in two years during the 2013 and 2014 growing seasons. Following a combined analysis of variance, multivariate statistical analyses such as simple correlation coefficients, factor analysis, stepwise analysis, path analysis, and cluster analysis were administered on combined means. The correlation coefficient analysis showed a significant negative correlation between seed yield and number of capsules per plant and number of seeds per capsule. Correlation between germination period and seed yield was positive and significant at 5% probability level. Factor analysis divided the 14 measured variables into five factors. In the stepwise regression analysis for seed yield as the independent variable, four traits including number of capsules per plant, first capsule height, number of seeds per capsule, and stem length to first capsule were entered into the regression model in four steps with r2 =0.72. The regression coefficient of number of capsules per plant, number of seeds per capsule, and stem length to first capsule were negative and the regression coefficient of the first capsule height was positive and significant at the 5% probability level. The path coefficient analysis based on seed yield as a dependent variable implicated that the number of seeds per capsule had the highest negative direct effect on seed yield. The highest negative indirect effect on seed yield was related to the number of capsules per plant through the number of seeds per capsule. Cluster analysis using Ward’s method divided 18 investigated lines into five clusters. 相似文献